Importance of hoof health in dairy production

Bad hoof health is an increasing and expensive problem in intensive dairy productions all over the world. Preventive interventions are important in order to obtain a sustainable production, both from an economical and animal welfare aspect. Hoof disorders are possible to prevent by a correct management and early detection of affected animals, regular claw trimming and a clean and dry environment is essential. Investment in prevention of hoof disorders is therefore profitable for the farmer, and this report could provide a basis for the farmer for prevention of hoof problems. The aim of the report is to define the importance of good hoof health among dairy cattle, in order to have a well-functioning and economically robust milk production.

ABSTRACT

The reported prevalence of different hoof disorders in dairy herds has fluctuated during the past years, which most likely is a result of different management systems as well as differences in study design. The prevalence of digital dermatitis has increased in both free- and tie stalls during the past 20 years with extensive variation between herds. However, the increase has been more distinct in free stalls. Statistics from Kungsängens research center show that heel-horn erosion and haemorrhage are the most common types of disorders in the investigated herd. The statistical analysis showed that incidence of haemorrhages decreased milk yield by on average 1.7 kg/day, despite of parity and lactation period. The results indicate that haemorrhages might be a more severe hoof disorder in dairy production than anticipated and that the condition negatively affects both animal welfare and economy of the production. Thus, preventive interventions and special attention to haemorrhage is of great importance. Generally, hoof disorders are prevented by regular hoof trimming, good environmental hygiene, and special attention to cows in sensitive periods. It is also of great importance to find affected cows at an early stage especially for cows with contagious diseases (e.g. digital dermatitis and heel-horn erosion). The total cost of a lame cow is approximately 245 Euro. However, the total cost of one case of sole ulcer is 160 € while the total cost of one case of digital dermatitis is 99 €. This means that one case of sole ulcer has greater economic impact than one case of digital dermatitis. The prevalence for digital dermatitis ranges from 20 % to 35 % while the prevalence for sole ulcers ranges from 4 % to 10 %. Since the prevalence of digital dermatitis is higher in many herds, the herd specific costs for digital dermatitis, in a 100-cow herd, is 1973 € (20 % prevalence) or 3453 € (35 % prevalence) while the herd specific costs, in a 100-cow herd, for sole ulcer is 641 € (4 % prevalence) or 1282 € (10 % prevalence). This means the total economic impact of digital dermatitis could be higher than for sole ulcer in a specific herd.

INTRODUCTION

Hoof and leg problems in dairy herds have increased over the past decades (Clarkson et al., 1996; Somers et al., 2003) and are now the third most important and costly disease complex facing today’s dairy farms (Watson, 2007). Culling due to bad hoof health in Sweden has increased from 3 % to 6 % during the last 20 years (Manske et al., 2002). According to a study by Manske et al. (2002), over 72 % of the cows in Swedish dairy farms have some kind of hoof lesion. The increase in hoof and leg disorders might be due to a more intensive production with an increased milk yield (MY) combined with increased use of loose housing systems and less attention given to each cow (Swedish Dairy Association, 2011).

Not only is the pain caused by bad hoof health a major welfare problem, but several studies have also pointed out the economic impact of hoof problems in dairy farms, where the direct costs of treatment represent only a small proportion of the total costs (Rushen et al., 2004). Lameness has a negative impact on feed intake due to reduced ability to walk and to stand at the feeding station (Bach et al., 2007). Also, lameness has been shown to negatively affect MY and quality (Green et al., 2002; Borderas et al., 2007), probably as a consequence of reduced feed intake and less frequent visits to the milking unit if an Automatic Milking System (AMS) is used (Bach et al., 2007). A study performed by Green et al. (2002) indicated that the total loss in MY during 305 days lactation was approximately 360 kg. Lameness is also associated with reduced fertility and according to Sprecher et al. (1997) and The Alberta Dairy Hoof Health Project (2011), some cows that are culled because of obvious reproductive problems may in fact be suffering from undetected lameness.

The use of AMS is becoming more common in dairy farms, especially in Europe (Borderas et al., 2007), and is proposed to reduce manual labour and at the same time increase MY by increasing milking frequency (Borderas et al., 2007). However, successful milk production with AMS depends on cows voluntarily visiting the milking unit (Rushen et al., 2004; Bach et al., 2007; Borderas et al., 2007) which makes the consequences of hoof and leg disorders even more severe. Studies have shown that lame cows are less willing to visit the milking units (Rushen et al., 2004; Bach et al., 2007), this results in fewer milkings per day, which not only leads to a decreased MY (Borderas et al., 2007) but may also increase the risk for mastitis (Agenäs, 2011). Also, when cows do not go to the milking unit voluntarily, the labor is increased since cows have to be fetched and brought to the unit manually (Borderas et al., 2007).

Milk yield is generally lower in organic dairy production in contrast to conventional dairy production. This seems to be due to the fact that high milk yield needs to be supported by an energy rich feeding plan, often accomplished by feeding high amounts of concentrates (Bergsten, 2003). One of the important differences between KRAV-certified organic dairy herds and conventional dairy herds is the feeding plan, where the feeding of concentrates is restricted in KRAV-certified organic dairy cows (KRAV, 2011: 5.7.12). Also, for the KRAV-certified organic dairy cows the roughages fed ad libitum (KRAV, 2011: § 5.7.11). A high milk yield can influence the incidence of hoof diseases (Hultgren et al., 2004), which indicate that the prevalence of hoof diseases in organic dairy cows is lower than in conventional dairy cows.

Hoof diseases can be divided into two different categories, infectious inflammatory diseases and non-infections problems caused by environmental factors. The first category includes diseases such as heel horn erosion (HHE) and digital dermatitis (DD) while the second includes laminitis and sole ulcer (SU) (Manske et al., 2002).

Sole ulcer is the most common cause of lameness (Watson, 2007) and is formed when the corium of the hoof is exposed or “pinched” (Watson, 2007; Jordbruksinformation, 2002). The condition is an animal welfare issue and is also very costly and recovery of the horn is slow. Sole ulcers are mainly treated with claw trimming but it is also important to allow re-growth of the horn by unburdening the damaged hoof.

Digital dermatitis, also known as papillomatous digital dermatitis (PDD) (Read & Walker, 1998), was first described in Italy 1974 (Cheli & Mortellaro, 1974) and is now recognized throughout Europe, USA, Australia and Japan (Watson, 2007). The disease is caused by the bacteria Spirochaete, which has a predilection for keratin hence causing damage to skin surfaces and the horn of the hoof. Spirochaete moves rapidly in wet environments and is quickly killed by drought: it is therefore associated with water and moist areas of the body and environment. The disease can be divided into different stages due to the severity of the lesions and the lesions can in severe cases cause lameness. Cows suffering from DD often lift and shake the infected leg, as if trying to remove something. Further on, some people can detect DD by its smell. Treatment of DD involves specific antibiotics or disinfection with copper sulphate, formalin, zinc sulphate, peracetic acid or other disinfectant compounds.

Heel horn erosion is a common hoof lesion mainly associated with a wet and slurry environment. The keratin in the corneous cells in the hooves is dissolved by urine and the connection between the cells is broken down by manure, which in turn leads to degradation of the heel horn (Andersson, 1982). The heel horn can be further broken down by the bacteria Bacteroides nodosus, which generally occurs in the gastrointestinal canal of the cow (Johannesson, 2003). Heel horn erosion can develop secondarily into DD and is then called “contagious HHE” (Johannesson, 2003). Affected cows usually get febrile and depressed which leads to reduced feed intake and hence lower MY (Manske, 2002). Minor lesions of HHE can heal spontaneously, but generally, claw trimming is the main treatment for this disease. Also, foot baths containing formalin can be an effective treatment (Somers et al., 2005c).

The aim of the literature review in this project is to investigate how the prevalence of lameness, SU, DD and HHE has developed during the past decades in intensive dairy production systems in Europe and North America. The risk- and preventive factors for the diseases will be investigated and the cost of the specific diseases as well as the economic benefits of prevention will be discussed. Based on the results of our investigation, future prospects of hoof problems will be estimated. An statistical analyze of data from Kungsängen will also be done. In this statistical analysis, the correlation between MY, type of hoof disorder and number of daily visits in the AMS will be investigated. The aim of the total report is to define the importance of good hoof health among dairy cattle, in order to have a well-functioning and economically robust milk production. The report could provide a basis for the farmer for prevention of hoof problems.

LITERATURE REVIEW

HOOF PROBLEMS, PREVALENCE/INCIDENCE

During the 1990’s and 2000’s there have been several reports of hoof health problems in Europe and North America of dairy cattle. The results of the different studies are presented in the text and organized under the different rubrics/years depending on when the data were collected. For further information about the studies see table 6 and 7 in the Appendix.

Prevalence between 1990 and 1999

Lameness/Severe Lameness

In a report from United Kingdom (Clarkson et al., 1996) the mean prevalence of lameness for winter and summer on the 37 farms was 25 % and 18.6 % respectively, with 20.6 % as the total mean prevalence at cow-level. The mean incidence rate for winter and summer (pasture) were 31.7 and 22.7 %. The total incidence rate for the same farms was 54.6 new incidences/100 cows and year. Data regarding lesions collected in this work were further analyzed by Murray et al. (1996). Of all the lesions that were associated with lameness, 92 % occurred in the hind limb and 8 % in the front limb. In the hind limb the outer claws were more affected than the inner claws or the skin. The pattern was different in the front limbs with more frequently affected inner than outer claws or the skin. Severe lameness was often associated with penetration of the sole by foreign bodies, interdigital necrobacillosis and/or sandcrack (Murray et al., 1996). Hedges et al. (2001) shows that the incidence rate in a study in United Kingdom for lame cows were around 70 % per year. In another study in United Kingdom involving 45 220 cows and heifers the mean annual lameness rate was 23.7 %. There were less lameness among the cows housed in straw yards (70 herds), with an average rate of 17.7 %, than in the cows housed in cubicles (213 herds) 25.5 %. The rate of lameness tended to be higher in bigger herds than in the smaller and there were also more lameness in winter (Oct-Mars) than in summer (Whitaker et al., 2000).

A Danish study found that the incidence of lameness during a lactation was 6.92/100 cows and that cows calving in the summer period (pasture) had a lower frequency of lameness than cows calving in the winter period. The study suggested that lameness increased with herd size (Alban, 1995). From a Swedish study Manske et al. (2002a) reported that the overall prevalence of lameness was 5.1 % at cow-level with a huge variation between herds 0-33 %.

In another study the prevalence of lameness in US dairy herds determined to 13.7 % in summer and 16.7 % in spring. There were significantly differences between tie and free stalls. During the summer the tie stalls had 14.1 % lameness and the free stalls had 12.2 % lameness. The prevalence during spring was 15.3 % in tie stalls and 21.9 % in the free stalls. The prevalence of lameness was in average estimated to be 2.5 times higher than what was estimated by the farmer (Wells et al., 1993).

Sole Ulcers

In the Netherlands Frankena et al. (1991) found that the prevalence of SU during the pasture period was 4.4 % and during the housing period it was 5.5 %. In a United Kingdom study Murray et al. (1996) identified that SU was attributed to 28 % of the lameness causes and was more common during winter than summer (pasture) (Murray et al., 1996). According to the study from Sweden among the cows SU occurred with 8.6 %, ranged from 0 to 33 %, and affected the hindclaws (8.3 %) more than the frontclaws (0.5 %) (Manske et al., 2002a).

Digital Dermatitis

In a study performed at 59 dairy farms in the Netherlands the prevalence of DD was analyzed both during pasture and housing period. During the pasture period the prevalence was 8.1 % and during housing period the prevalence was 13.8 %. During the housing period the cases of DD were also more severe (Frankena et al., 1991). Among calves in the Netherlands hind claws of 1141 calves were examined and the prevalence of dermatitis digitalis was very low (0.16 %) (Frankena et al., 1992). A report received from United Kingdom shows that of all the lesions associated with lameness 8 % was due to DD. The lesion was more common during winter than summer (pasture) (Murray et al., 1996).

A study based on a questionnaire answered by the farmers indicated that the herd prevalence of PDD in California to be different in different parts of the state, south (73.5 %) and central regions (68.8 %) had significantly more affected herds than did the north region (23.1 %) and the northern coast (33.3 %). The mean cow prevalence for the affected herds was 11.6 % (Rodriguez-Lainz et al., 1996). According to another study in USA, 43.5 % of all the herds and 11.9 % of all the cows in the study had PDD. The prevalence for heifers was 4.2 %. When the herd size increased so did the portion of herds that were affected. Among herds with less than 100 cows 36.4 % of these herds had infected cows, while among herds with 200 or more cows the ratio of infected herds increased to 80.3 %. All the infected cows were not lame, 81.9 % of the cows with PDD were also lame, and 85.9 % of the heifers with DD were also lame. At this time 78 % of the herds with infected cows stated that the problem fist occurred during 1993 (Wells et al., 1999). Among culled adult cattle in USA the prevalence of PDD was 29 % in a study (Brown et al., 2000).

Heel-horn erosion

According to the study from United Kingdom lesions that were associated with lameness 4 % consisted of HHE and the portion of the affected cows whit HHE were more common during winter (80 %) than summer (20 %) when the cows were on pasture (Murray et al., 1996). In Sweden Manske et al. (2002a) found that heel horn erosion affected the hind claws (38 %) more than the front claws (13 %). Of all the cows 41 % had HHE and the minimum and maximum levels ranged between 0.0 and 91 %. HHE was one of the most common lesions in this study.

Prevalence between 2000 and 2011

Lameness/Severe lameness

A study in Wisconsin could find the prevalence of lameness during the summer to 21.1 % ± 10.5 % and winter it was 23.9 % ± 10.7 %. Severe lameness had a prevalence of 3.0 %, ranging from 0.0 % to 16.7 %, during summer and 3.2 %, ranging from 0.0 % up to 12.3 %, during winter. In the article it is not clear whether the cows were on pasture or not during the study (Cook, 2003). In another study in Minnesota the average prevalence of lameness for all groups were 24.6 %, with a range from 3.3 % to 57.3 %. The prevalence of severe lameness was 6 % (Espejo et al., 2006). Higher than for Cook (2003), in spite of different scoring systems they stated that the results can be compared and that score 4-5 in this study is similar to score 4 in the 1-4 scoring system. The prevalence estimated from the herd manager was 3.1 times lower than that from the investigators (Espejo et al., 2006).

A study in United Kingdom reported that of all the cows in the study the prevalence of lameness for at least one lesion was 34.9 % (Amory et al., 2008). Barker et al. (2010) reports from United Kingdom that the prevalence of lameness of cows that had score 2 were 31.5 % and for score 3 were 5.3 %.

In a Danish study, lameness occurred in 5 % of the cows and out of that, 2.3 % were severe lame (Capion et al., 2008). A study from Norway reports that hind claws were more affected by lameness than front claws. The prevalence of lameness for hind claws in tie-stalls was 0.7 % among all cows examined and in free-stalls the number was slightly higher, 1.6 % (Sogstad et al., 2005a). In a free stall study in Norway, lameness among all cows examined and scored 3-5 were 7.7 % and only 0.2 % were scored as the most severe cases of lameness (5) while the rest of the cows were scored 1 (76.7 %) to 2 (15.7 %). Most lameness cases were found when alley floorings were of slatted compared with solid (Fjeeldas et al., 2011).

Sole ulcers

In a study in the Netherlands the cow-prevalence for SU was 4.8 % when the hind limbs were examined (Somers et al., 2003). According to another study in Netherlands the prevalence for SU was 5.4 % at cow-level (Van der Waaij et al., 2005). In another study in Netherland the number of cows affected of SU varied between 0-26 %, and the average value were 5.6 %. Of all the herds examined 85 % had the lesion (Holzhauer et al., 2008). Sogstad et al. (2005a) reported that in a study in Norway were the hind claws were examined the prevalence for SU in free stall to be 3.0 % and in tie stall 2.6 % at cow-level. The prevalence of SU in heifers in a study in Norway reported to be low, front claws were affected with 0.3 % and hind claws with 0.5 % (Sogstad et al., 2005b). According to another study in Norway the prevalence for SU was 2.9 % in hind claws in free stalls among all cows examined (Fjeeldas et al., 2011). In a study from Finland Kujala et al. (2009) found that 442 out of 11 302 cows (3.9 %) had SU in tie stalls. In free stall 226 cows out of 5490 had SU (4.1 %). Capion et al. (2008) found that the prevalence for SU were 6 % in a study in Denmark. Amory et al. (2008) reported in United Kingdom that 230 cows out of 1824 had SU (12.6 %) and the incidence was at cow level 6.8 %. Cramer et al. (2008) found that the prevalence of SU in Canada was 4.7 % at cow level and it occurred in 70.4 % of the herds. In free stalls the number was higher, 9.3 % of the cows were affected and the problem occurred in 89.5 % of the herds (Cramer et al., 2008). Among lame cows in the US 16 % were determined having SU, and the annual incidence risk was found to be 7.8 % (Sanders et al., 2009).

Digital Dermatitis

According to a study from Netherlands, were the hind limbs were examined, the cow prevalence was 37.4 % and varied between herds during housing period from 1 to 63 % and during pasture from 2 to 73 %. Cows on concrete floor had an average prevalence of 30 %, and all of the herds on concrete floor were affected. Cows on straw yards were less affected than cows on concrete (Somers et al., 2003). In another study from the Netherlands the cow prevalence of DD was 21.2 % (Holzhauer et al., 2006). Van der Waaij et al. (2005) found that the prevalence at cow-level for DD in a study in Netherlands were 21.7 %.

In a study in United Kingdom among 1824 cows 137 (7.5 %) were diagnosed to have DD and the incidence were at cow-level 6.3 % (Amory et al., 2008). Capion et al. (2008) found that 85 % of the herds in a study conducted in Denmark had DD, and in the herds an average of 19 % of the cows had DD. In another Danish study DD was observed at least once in 62 % of all the cows, in a study conducted during 12 weeks and with 6.9 days as mean interval for the observations (Nielsen et al., in press).

Digital Dermatitis was one of the most common claw lesions in Canada in a study of Cramer et al. (2008). According to this the cow-prevalence of DD in tie stalls was 9.3 % and the number of herds affected was 69.7 %. The prevalence was higher for free stalls with 22.9 % of the cows’ affected and 92.1 % of the herds.

Heel-horn erosion

In a study in Norway the hind claws were examined and the prevalence for HHE in free stalls was 39.6 % and 8.1 % among all animals in tie stalls. Heel horn erosion prevalence was reported to be lower in larger herds (Sogstad et al., 2005a). Another study performed in Norway by Sogstad et al. (2005b) reported the prevalence of HHE in heifers to be lower in front claws 8.9 % than in hind claws 11.4 %. Fjeeldas et al. (2011) reported from a study in Norway that the prevalence for HHE in hind claws to be 18.1 % in free stalls. In a study from Finland 306 cows had HHE out of 11 302 in tie stalls (2.7 %). In free stalls 1313 cows out of 5490 cows had the problem (23.9 %) (Kujala et al., 2009). Cramer et al. (2008) found that HHE in a study in Canada occurred in 8.3/8.4 % in tie and free stalls respectively and herds affected were 67.6/68.4 % respectively.

RISK FACTORS AND PREVENTION

In this section factors that have an impact on the development and prevention of lameness, SU, DD and HHE are reviewed. For further information about the studies referred to in the text, see table 8 in the Appendix.

Risk factors for lameness

Lameness is a multifactorial condition and can be caused by infectious agents (e.g. foot rot), laminitis and conformational or other lesions. It is also commonly caused by hoof lesions such as white line disease, sole-induced toe ulcers, sole-, toe- and heel ulcers, sole punctures and thin soles (Sanders et al., 2009). According to Barker et al. (2008), the three most frequently reported lesions related to lameness are SU, white line disease and DD, which is confirmed by an earlier study by Hedges et al. (2001). Further, in a study by Sanders et al. (2009), the most common causes of lameness were thin sole-induced toe ulcers, SU and thin soles. Also, a study by Alban et al. (1996) showed that the risk of lameness increases if the cow has suffered from lameness before. According to the authors, this might be a result of increased susceptibility, the recurrence of an old incident or a persistent case.

Environmental and management factors

The risk of lameness due to hoof lesions and infectious agents is highest after calving. This increase is an effect of many factors. Rumen acidosis, which is the main risk factor for lameness (pers. com. Strudsholm, 2011) is greatest post-calving when the cow has a high demand for energy and therefore often is fed a high concentrate ratio. Hence, feeding a high starch/low fiber diet, which is predisposing for rumen acidosis, increases the risk of lameness (Blowey, 2005; pers. com. Strudsholm, 2011). Two weeks before and after parturition, elevated levels of an enzyme referred to as “hoofase” causes increased flexibility of the suspensory system within the hoof. This leads to increased movement of the pedal bone and a greater risk of bruising of the corium. Also, increased time standing up results in increased hoof wear. Combined with a decreased growth, which commonly occurs at postpartum, the extra wearing of the hooves leads to thinning of the sole (Blowey, 2005). The standing time is naturally prolonged after calving but management factors can enhance this even more. For freshly calved heifers, which often enter the milking parlour last, waiting in the holding area (HA) contributes to longer standing times. Further, increased feed consumption at the on-set of lactation results in increased time standing up. The effect of this is even worse if the cow stands inactive since the vascular pumping mechanism of the heel and digital cushion becomes impaired. These factors are important to bear in mind when building new barns as insufficient feeding spaces, overcrowding or blind-ending narrow passageways might contribute to prolonged standing times (Blowey, 2005). After calving, the immune system is suppressed and the risk of periparturient diseases is increased. This also increases the fragility of the corium, resulting in increased susceptibility of the hooves and total cessation of the horn production might occur in extreme cases. This is predominantly the case in heifers which have been reared separated from the main herd.

A study by Alban (1995) showed that cows that calved during the housing period (October-April) had a higher risk of developing lameness compared to cows that calved during the pasture period (May-September). This could, according to the author, be related to differences in climate, feeding and environment. Overall, longer grazing time, i.e. more outdoor exercise, reduces lameness (Bielfeldt et al., 2005) and farms using a half grazing – half housing system have lower incidence of lameness (Faye & Lescourret, 1989). Since exercise probably reduces the risk of lameness (Gustafson, 1993; Alban, 1995), loose housing systems and tie-stall barns with exercise are suggested to reduce the frequency of lameness compared to tie-stall barns without exercise (Bielfeldt et al., 2005). Though, it is of great importance that the exercise area is in proper condition (Alban, 1995, Cramer et al., 2009). However, other studies show that the frequency of lameness is somewhat higher in loose housing systems (Faye & Lescourret, 1989; Sogstad et al., 2005b). This might be due to a higher degree of manure and moisture in these systems and therefore a proper removal of manure and effluents is of great importance (Blowey, 2005). Wet flooring not only reduces the hardness of the hooves and makes them more susceptible to wear and damage but may also increase the risk of transmission of bacteria causing infectious hoof diseases (Rushen et al., 2004). The foundations of the floors in the loose housing system is an important factor influencing the frequency of lameness and hard concrete foundations have a negative effect on lameness (Faye & Lescourret, 1989). Rubber matted floors, especially in the holding and feeding area (FA) (pers. com. Strudsholm, 2011), can reduce the incidence of lameness although overgrowing of the hooves might be a problem (Blowey, 2005; Kremer et al., 2006). However, this can be compensated for by the fact that rubber floors reduce the trauma and thereby the horn growth is reduced (Blowey, 2005). Another possible reason for higher frequency of lameness in loose housing systems is that the lying-, standing-, milking- and feeding areas are distributed between different stations compared to tie-stalls, which means that the hooves are exposed to a much more complex environment (Sogstad et al., 2005b).

The usage of sand as bedding material has increased in Denmark, with good results. The sand has a good effect on cow comfort and hoof health since it, if managed properly, leads to prolonged lying times and dryer hooves (pers. com. Strudsholm, 2011).

Herd size might have an effect on the risk of lameness; however the studies show inconsistent results. According to Alban (1995), the risk increases with increasing herd size. Groehn et al., (1992) on the other hand, found that a herd size of 50-99 cows was associated with the highest frequency of lameness and that larger herds meant a lower risk. On the contrary Sogstad et al. (2005b) found no association between herd size and lameness.

Cow factors

Age and parity have effect on the risk of developing lameness. Alban (1995) found that the incidence was higher for cows in their first and fourth lactation than for cows in parity two and three. According to the author, the high frequency in the fourth lactation might be due to wearing of the hooves while in the first lactation the abrupt environmental and metabolic changes associated with first calving might explain the increased incidence. Further, culling of lame cows, i.e. selection for strong extremities, results in lower frequency of lameness in the second lactation. However, other studies indicate an obvious tendency against a higher probability of lameness in older cows (Groehn et al., 1992; Bielfeldt et al., 2005; Sogstad et al., 2005b).

Specific breeds have a higher tendency to develop lameness. For example, the breeds Danish black and white, Red Danish or Danish red and white have higher risks of developing lameness than Danish Jersey (Alban, 1995). This might suggest that lameness is associated with body weight since Jersey is a considerably lighter breed compared to the others which all are heavy breeds. Moreover, larger breeds have higher MY which also could explain the differences, since high MY is associated with an increased risk of developing lameness (Alban, 1995; Green et al., 2002). Also, the intense feeding of high yielding cows might increase this risk (Alban, 1995). A study by Tranter et al. (1993) showed that white hooves are more susceptible to lameness than black hooves and since black hooves are more common for Jersey cows, this might also have an impact on the result. The study also indicated that the concavity and hardness of the sole as well as the sole and heel moisture are essential factors for the risk of lameness. The conformation of the hoof is heritable, hence bulls with a good depth of heel and upright angle of the front hoof wall should be chosen for breeding (Blowey, 2005).

Prevention of lameness

An important tool for preventing hoof damage is claw trimming, which corrects the angles of the hoof and ensures that the cow can load the hoof in a correct way (Blowey, 2005). Animals kept in different housing systems need different trimming depending on the environment. The frequency of trimming is individual but the main recommendation is at least twice a year. However, additional trimming and attention should be given to cows with already existing hoof problems. Footbaths are important for preventing infectious causes of lameness and should be practiced regularly for preventive purposes (Blowey, 2005). However, according to Strudsholm (pers. com., 2011) this is not necessary if right management is applied. Another factor with presumable effect on lameness is the supplemention of high yielding cows with biotin. This B-vitamin is essential for keratinization which in turn is of major importance for the structural composition of the hoof horn (Hedges et al., 2001).

Risk factors for sole ulcers

Environmental and management factors

Sole ulcers are mainly caused by mechanical stress, hence any object that can cause physical damage is considered as a risk factor (pers. com. Strudsholm, 2011). The use of hard and abrasive cow tracks and alleys, such as concrete and roadways, increases the risk of SU since it increases the wear of the claw horn which leads to reduced concavity of the sole. However, in a study by Kremer et al. 2006, rubber-matted slatted flooring in loose housing system increased the incidence of SU compared to concrete-slatted flooring. According to the authors, this might be a result of an increased horn growth and thus a greater (i.e steeper) toe- and heel angle. However, cows on rubber flooring showed increased activity, suggesting rubber to be a more comfortable walking surface compared to concrete flooring. When lying surface is uncomfortable, the cows tend to stand for longer periods which also increase the risk of SU. Thus, management to avoid continued exposure of cows to hard lying and walking surfaces should contribute to a reduced incidence of SU (Barker et al., 2008). Too frequent scraping of the allies could increase the prevalence of SU. One suggested reason to this might be decreased lying times and increased aggressive social interactions which in turn can increase the strain placed on the suspensory apparatus of the third phalanx (Cramer et al., 2008). Also, frequent scraping might increase the risk of mechanical damage (pers. com. Strudsholm, 2011). The type of bedding also affects the development of SU. Sparse bedding compared to deep bedding or pasture on the lying surfaces was found to increase the risk of developing SU (Barker et al., 2008). A study by Holzhauer et al. (2008) indicated that the risk of SU was lower in stalls with mattress bedding. However, no effects of concrete stall base compared to rubber mats were found by Sogstad et al. (2005b) but this might be due to the fact that the majority of the mats in the study were of the hard type or not provided with sufficient bedding material. In addition, if the rubber mats are not well fitted or properly cleaned, they might act as a reservoir for microorganisms (Sogstad et al., 2005b). Mattresses on the other hand, are softer and easier to keep clean and are therefore a better alternative in free stalls. A comfortable lying-space is even more important during the first weeks postpartum since the incidence of SU can be reduced by encouraging maximized lying time after calving (Blowey, 2005).

Cow factors

High body weight and high MY might increase the risk of SU (Envoldsen et al., 1991). Also, parity might have an impact on the development of SU. According to a study by Sogstad et al. (2005b) on cows in short free stalls, the frequency of SU was higher for cows in their first lactation. On the contrary, other studies show that the risk increases with increasing parity (Holzhauer et al., 2008; Barker et al., 2008; Sanders et al., 2009). The study by Sogstad et al. (2005b) also revealed that the frequency of SU was highest 5 to 7 months after calving which is confirmed by a study by Sanders et al. (2009) that revealed that the risk of SU was greatest in mid lactation. Further, Holzhauer et al. (2008) found that the risk for cows to develop SU was highest at or after peak lactation. The presence of other hoof diseases, such as HHE (Alban et al., 1996), laminitis (Alban et al., 1996; Holzhauer et al., 2008), sole haemorrhages (H), white line disease and interdigital hyperplasia, increases the risk of developing SU. Hence, prevention of these diseases reduces the frequency of SU (Holzhauer et al., 2008).

Prevention of sole ulcer

Trimming of the hooves might act as a preventive tool for SU but it has to be performed at the right time. Envoldsen et al. (1991) found that trimming in the summer was strongly associated with the risk of developing SU. Instead, preventive trimming at the end of the housing period reduces the risk of developing SU (Holzhauer et al., 2008).

Risk factors for digital dermatitis

Environmental and management factors

A poor environmental hygiene with insufficient removal of moist and manure, can erode the skin and cause DD (Vink, 2004). Somers et al. (2005a) found that slatted floor in a cubical system with manure scrapers lowered the odds for DD due to a more efficient removal of the manure. Another study by Somers et al. (2003) evaluated the effect of slatted floor compared to slatted floor with manure scrapers, solid concrete floor, straw yard and zero-grazing feeding systems in Dutch dairy farms. The results showed that the cows in the straw yard had the lowest incidence of hoof disorders (55 % – 60 %). In contrast over 80 % of the cows exposed to concrete floor had a hoof disorder. Further, cows exposed to the slatted floors with manure scraper had less frequent markings of DD compared to the slatted reference floor without manure scrapers. For the zero-grazing feeding system the risk of developing hoof disorders depends on whether it is during a pasture or housed period. The risk of developing hoof disorders was higher during the pasture period compared to the housed period. In general 30 % of the total number of cows was infected with DD. On the other hand studies from different parts of the world has shown a decreased prevalence of DD when the cows are on pasture (Frankena et al., 1991; Murray et al., 1996). Further, solid grooved concrete floor in the housing system provides a higher risk for DD compared to solid non-grooved concrete floors (Barker et al., 2008). This seems to be because of an increased wear of the hooves on a rough surface compared to a softer surface. Similar results were observed by Somers et al. (2005a) when the effect of slatted floors, solid concrete floors, grooved floors and straw yard was evaluated. In this experiment the straw yard resulted in the lowest incidence of DD and cows on slatted floor had fewer registrations of DD than cows on solid concrete floor and grooved floor. Singh et al. (1993) found that cows in a straw yard lay down more often in contrast to cows in cubicle systems. This indicates a higher cow comfort in straw yard systems and might contribute to a lower frequency of DD.

A recent Norwegian study by Sogstad et al. (2005a) showed that free stalls have higher prevalence of DD than tie stalls. According to the authors, the reason for this is that DD is spread more easily in moist and unhygienic environments and that exposure of the cows to moist are more continuous in free stalls than in tie stalls. One easy solution could be to increase the frequency of the scrapers; however this might instead increase the prevalence of DD (Cramer et al., 2009). This is due to more effective spread of the infective bacteria. Different lengths of cubicles do not affect the risk of DD (Somers et al., 2005a). However, it is important to provide a good lying comfort and reduce the time standing up in order to minimize the risk of DD (Vink, 2004).

Access to pasture is associated with DD (Cramer et al., 2009) and it has been indicated that cows with more than eight hours access to pasture have higher risk of developing the disease than cows with no access to pasture (Holzhauer et al., 2006). However, these results differs from a couple of other studies that indicate that restricted access to pasture increases the risk of developing DD (Somers et al., 2005a; Onyiro et al., 2008).

A fast rise of concentrate in the ration after calving (less than two weeks to maximum amount) increases the risk of developing metabolic stress and thus the risk of DD is elevated. Instead, a medium step-up (2-3 weeks) ration is recommended (Somers et al., 2005a). The herd size also has an impact on the prevalence of DD. A medium- or large herd (60 to 85 cows) has a higher risk than a small herd (less than 45 cows) (Holzhauer et al., 2006) and a high stocking density can cause stress and increase the risk of DD (Vink, 2004). Further, stressful situations such as poor introduction to new systems and lack of training of heifers to cubicle systems results in longer time standing and thus higher risk of DD. When buying livestock, the risk of introducing DD is very high because of the high risk of spreading the disease.

Cow factors

Cows up to six months postpartum have an increased risk of developing DD (Barker et al., 2008; Somers et al, 2005a). Also, the risk decreases with increasing parity (Holzhauer et al., 2006; Somers et al., 2005a) and first-parity cows have a higher risk of developing DD compared to cows in later lactations (Rodriguez-Lainz et al., 1999). This may be due to an increased immunity with age as well as a higher culling probability. Moreover, first parity cows are exposed to many changes such as changes in nutrition, metabolism and environment (Somers et al., 2005a) thus increasing the risk of DD in first parity cows. Lactating cows have a higher risk of developing DD than dry cows and the risk is highest during peak lactation (30 to 60 days) (Holzhauer et al., 2006). One reason for the lower risk of DD in dry cows might be that dry cows are often fed more roughage than lactating cows, thus producing more solid manure. This leads to less wet and unhygienic floor condition which decreases the risk of DD (Vink, 2004). Dry cows do however have a higher risk of developing DD if they are introduced to a lactating herd before calving (Somers et al., 2005a). Calving season also affects the risk of DD and Rodriguez-Lainz (1999) demonstrated an increased risk of developing PDD during the winter compared to other seasons.

The anatomic structure and conformation of the hooves is associated with the risk of DD (Vink, 2004). Hooves with low heel height are more exposed to manure and slurry and can therefore be a contributing factor to the development the disease. Cows that have suffered from other hoof disorders, such as interdigital dermatitis, interdigital phlegmon and HHE, have an increased risk of developing DD (Holzhauer et al., 2006). Hence, it is important to minimize and attend other hoof disorders to prevent development of DD.

The type of breed also has an impact on the risk of developing DD. A study by Holzhauer et al. (2006) showed that Holstein-Friesan breeds have a higher risk of developing the disease than the Meuse Rhine Ijssel breed (MRIJ). Similar Rodriguez-Lainz (1999) found that Holstein crossbreeds were more susceptible to the disease than German Red-Pied (dual-purpose). Onyiro et al. (2008) found a negative genetic correlation between DD and longevity, MY and milk fat. This suggests that breeding for resistance against DD will have a positive effect on the production. In the same study cows with low locomotion scores and bad leg and feet composite had a reduced risk of DD.

Prevention of digital dermatitis

Trimming can decrease the risk for DD (Holzhauer et al., 2006; Somers et al., 2005a). However, the trimming must be performed regularly and with a maximum twelve months interval (Holzhauer et al., 2006). Somers et al. (2005a) found that intervals longer than seven months increased the risk of DD. Also, Wells et al. (1999) found that hiring a commercial claw trimmer with poorly washed equipment can help spreading the disease. Further, a bad trimming technique can increase the risk of developing the disease (Vink, 2004).

Rodriguez-Lainz (1999) investigated the frequency of PDD on cows that had access to foot-baths compared to cows that did not. Results showed that cows with access to foot baths had fewer registrations of the disease than cows without this access. This result differs from a study performed by Holzhauer et al. (2006) were the presence of foot baths did not affect the prevalence of DD. In a study by Cramer et al. (2009) spraying the hoofs with foot disinfection on cows in tie-stalls did not prevent DD to develop but instead rather increased the risk. This might however, be a result of inappropriate duration, frequency, type of disinfectant or concentration of the spraying (Cramer et al., 2009).

Risk factors for heel horn erosion

Heel horn erosion develops if the corneous tissue is broken down or if the synthesis of new tissue is interrupted. The origin of HHE is not fully investigated but the hygiene of the stable is of great importance. The bacteria causing outbreaks of HHE is primarily Bacteroides nodosus but Fusobacterium necrophorum is also contributive (Johannesson, 2003). Most cases of HHE are rather mild and thus not explicitly relate to lameness. However, it can develop into a more severe condition resulting in lameness. Also, HHE can make the hooves more susceptible to other hoof lesions such as SU, interdigital phlegmon and DD (Somers et al., 2005c).

Environmental and management factors

A wet and slurry environment is predisposing for HHE since it causes breakdown of the corneous tissue. If the animals are kept in a tie stall, the back hooves are mainly afflicted since the manure easily lands on the back of the cubicle. The area where the front hooves are placed is generally dryer and therefore the front hooves are not affected to the same extent. The bacterium Bacteroides nodosus normally occurs in the cow’s gastrointestinal canal and consequently in the feces. When the hooves come in contact with manure, the proteolytic enzymes of the bacteria break down the corneous tissue. This could be avoided by limiting the cow’s ability to move, but that will affect its ability to eat, drink and get up which is prohibited by the Swedish law of prevention of cruelty to animals (Johannesson, 2003). Further, HHE primarily arises when the animals are in close contact with each other like in loose housing systems (Manske, 2002).

Slatted floors with alley scrapers lower the risk of HHE compared to slatted floors without alley scrapers or solid floors with alley scrapers (Cramer et al., 2009). Further, slatted floors are preferred compared to solid concrete floors (Somers et al., 2005c). Relative to cubicle houses, there is a lower prevalence of HHE in straw-yard systems (Somers et al., 2005c).

Due to the exposure to feces, the prevalence of HHE is much higher in the housing season compared to the pasture season. Also the type of soil can be of importance and cows grazing on grassland with a mixed soil, e.g. sand and clay have a lower risk of developing HHE relative to cows grazing on grassland with sandy soil (Somers et al., 2005c).

Heel horn erosion can develop secondarily into DD. This is normally called “contagious HHE” since it is caused by contagious bacteria such as Fusobacterium necrophorum. Because of this, some herds have problems with the disease even though the stable is rather clean. Therefore it is of great importance to avoid introduction of infected animals to the herd (Somers et al., 2005c).

Cow factors

The risk of developing HHE is increased after calving due to the stress caused by the abrupt environmental changes. The risk for HHE increases with increasing parity and, as the cow gets older, the prevalence of more severe cases increases (Somers et al., 2005c).

Prevention of heel horn erosion

Sufficient cleaning and a dry environment are essential to control HHE and one solution could be to increase the frequency of the automatic alley scrapers (Cramer et al., 2009). Also, a higher intake of roughage can prevent the development of HHE since it makes the feces more consistent thus reducing the slurry on the floors (Somers et al., 2005c). HHE can be prevented by regularly claw trimming (Andersson, 1982) and foot baths containing formalin (Somers et al., 2005c).

THE ECONOMIC EFFECT OF DIFFERENT HOOF PROBLEMS

MATERIAL AND METHODS

The economic part of this project started with a literature review in different databases such as Web of knowledge. Different studies on economic aspects showed different costs of different hoof diseases depending on the study. The analyzed diseases were only SU and DD due to that no studies of economic effects on HHE have been found. Standardized tables were made and the data was put together in four different tables. A problem with our review is that all studies not have analyzed for the same parameters. The effect of this is that some parameters have been “missing” in the calculations. This results in differences in total costs for the chosen diseases depending on the structure of the study.

To facilitate the comparison of the costs from different countries and years we converted all costs to euro. We did also consider the different values of the sums. One SEK was equal to 0.11 Euro on 14 of November (Valuta, 2011). Calculations in table 1 were based on 1998 prices and on the inflation growth between year 1998 to 2010 and calculations in table 2 were based on inflation between years 2002 to 2010. These inflation calculations were made from Bank of England (14 November 2011).

LITERATURE REVIEW

According to Watson (2007) a division of the economic consequences due to hoof diseases can be made into indirect and direct costs. The direct costs have a direct effect on the production whereas the indirect costs are related to indirect effect like impaired fertility and less weight gain. Important to understand is that the cost for hoof diseases depends on the severity and type of lesion. It also depends on the cow’s MY and in which stages of lactation the cow is in when she gets affected. In the following text the direct costs from the tables are briefly explained. Veterinary treatment - labor, blocks and drugs depends on the severity and type of hoof disease, due to that some hoof diseases needs more treatments then others. Herdsperson’s labor also depends on severity and type of hoof diseases due to the time cost for ongoing treatments and daily care for the affected cow. Milk withdrawal time can be different from farm to farm depending on if the production is organic or not. The withdrawal time is also different for different kind of drugs and also for differ hoof diseases. Reduced yield are often due to the pain that the disease causes. The pain can lower the amount of milking times in the AMS per day and also the milk letdown reflex which affects the yield. Reduced feeding costs are the costs for the feed that the cow doesn’t eat due to hoof diseases.

The indirect costs in the tables are increased culling, extended calving interval and extra services (Watson, 2007). The last two can be merged into increased fertility costs. These costs are due to that hoof diseases aggravates the ability for the cow to carry out her reproductive functions and it also makes it harder for the herdsman to serve the cow at the right time. The expense for culling of cows is very high and since hoof diseases is one of the biggest causes for culling this makes good hoof health economically very important. The risk of increased culling is very dependent on the type of hoof disease, for example a SU will increase the chance of culling by 18 per cent while on the other hand a skin disease won’t affect the risk that much.

Sadly a hoof disease often relapse which also have to be taken into account when estimating the cost of hoof diseases (Watson, 2007). In table 1 the recurrence is sat to 0.5 which in other words means that each case of hoof disease will have a repeat cost of a half case. In table 2 the recurrence is sat to 0.4. When calculating on the recurrence only direct costs of veterinary treatment, herdsperson’s labor and drug withdrawals is taken into account.

Instead of only looking at certain hoof diseases, the diseases in tables 1 and 2 have been merged into different groups (Watson, 2007). In both tables the cost for SU is separate even though it is a horn disease. This has been made due to the high cost of this disease. In table 1 the hoof diseases except for SU is divided into horn diseases and skin diseases. In the group of horn diseases there are, SU, HHE, white line diseases, heel ulcers, foreign body penetrations, fissures, sole hemorrhages, and hematomas of the bulb and heel. Diseases that falls in to the category of skin diseases are DD, interdigital necrobacillosis (“foul”), per-acute interdigital necrobacillosis (“super foul”) and interdigital hyperplasias. In table 2 the diseases except SU are divided into either digital or inter-digital diseases depending on localization of the disease.

Table 1: The Costs of hoof diseases in Dairy Herds

Type of hoof disease

SU

Horn Disease

Skin disease

Average case of a hoof disease

Proportion of lesions %

21

41

38

 

Direct costs (€)

 

 

 

 

Veterinary treatment - labor, blocks and drugs

53.46

39.70

34.91

40.75

Herdsperson´s labor

16.02

8.06

8.06

9.81

Milk Withdrawal

3.15

2.57

2.57

2.69

Reduced yield

43.32

28.84

14.48

26.39

Reduced feeding cost

missing

missing

missing

missing

 Total

115.95

79.17

60.02

79.64

Indirect costs (€)

 

 

 

 

Increased culling

168.15

102.76

0

77.42

Extended calving interval (fertility)

88.11

48.06

28.03

48.85

Extra service (fertility)  

22.42

12.81

6.40

12.49

Total

278.68

163.63

34.43

138.76

 Total cost of a single limb case (direct and indirect costs)

394.63

242.80

94.45

218.40

Cost of repeat cases per affected cow and year (0.5)

36.36

25.14

22.74

26.59

Direct cost for a lame cow per year single limb case plus recurrence (0.5)

152.31

104.31

82.76

106.23

Total cost for a lame cow per year single limb case plus recurrence (0.5)

430.99

267.94

117.19

244.99

Source: (Kossaibati et al. 1999) Calculations are bases on 1998 prices and on the inflation growth between years 1998 and 2010. The exchange rate from (£) to (€) were made 11/14/2011.

Table 2: The costs of poor fertility and disease in United Kingdom dairy herds

Type of hoof disease

SU

Horn Disease

Skin disease

Average case of a hoof disease

Proportion of lesions %

21

41

38

 

Direct costs (€)

 

 

 

 

Veterinary treatment - labor, blocks and drugs

21.69

13.31

11.38

14.36

Herdsperson´s labor

14.08

7.03

7.03

8.52

Milk Withdrawal

1.56

1.26

2.51

1.80

Reduced yield

110.91

110.91

33.27

81.41

Reduced feeding cost

missing

missing

missing

missing

 Total

148.24

132.51

54.19

106.09

Indirect costs (€)

 

 

 

 

Increased culling

172.49

 105.41

 0.00

79.44 

Extended calving interval (fertility)

122.45

27.54

52.03

56.78

Extra service (fertility)  

21.28

11.53

5.91

11.45

Total

316.22

144.21

57.94

147.67

Total cost of a single limb case (direct and indirect costs)

464.46

276.72 

112.13

253.76

Cost of repeat cases per affected cow and year (0.4)

14.92

8.61

8.37

9.84

Direct cost for a lame cow per year single limb case plus recurrence (0.4)

163.16

141.12

62.56

115.93

Total cost for a lame cow per year single limb case plus recurrence (0.4)

479.38

285.33

120.50

263.60

Source: (Esslemont and Kossaibati 2002) Calculations on inflation is made between year 2002 to 2010 and with the exchange rate on 11/14/2011 from (£) to (€).

The cost calculated in table 3 shows a modulation made of Cha et al. (2010). A model to calculate economic losses occurring during hoof problems was used. The different parameters contributing to economic losses in this study are veterinary treatment cost, milk loss and decreased fertility. In the model the milk price was set to 0.23 € per kg. Feed cost was set to 0.15 € per kg dry matter. The parameter fertility was programmed with following settings, Pregnancy rate was 0.21 per month with a 60 days of voluntary waiting period. Maximum of calving interval was 20 months and least the involuntary risk for culling at calving was set to 2 %. The result indicated that an average SU cost 160.33 € and that an average case of DD cost 98.67 € (Cha et al, 2010). In SU the biggest economic part was from milk loss. In DD the economically most important part was the veterinary treatment cost.

Table 3: The cost of different types of hoof diseases in dairy cows calculated by dynamic programming

Type of hoof disease 

SU

DD

Proportion of lesions %

missing

missing

Direct costs (€):

 

 

Veterinary treatment - labor, blocks and drugs

45.45

41.69

Herdsperson´s labor

missing

missing

Milk Withdrawal

missing

missing

Reduced yield 

61.57

26.28

Reduced feeding cost

missing

missing

Total 

107.02

67.97

Indirect costs (€)

 

 

Increased culling

missing

missing

Extended calving interval (fertility)

53.31

30.70

Extra services (fertility)

missing

missing

Total

53.31

30.70

Total cost of a single limb case (direct and indirect costs) 

160.33

98.67

Cost of repeat cases per affected cow and year (0.4)

missing

missing

Direct cost for a lame cow per year single limb case plus recurrence (0.4)

missing

missing

Total cost for a lame cow per year single limb case plus recurrence (0.4)

missing

missing

Source: (Cha et al. 2010) Calculations with the exchange rate from 11/17/2011 from (US$) to (€).

In the analysis made by Oskarsson (2010) the economic factors has been described with a value and a price per unit, see Table 4. Two different cases of SU has been calculated, a severe and a veterinary treated case. In the severe case Oskarsson. (2010) has calculated that the MY is reduced with 500 kg with a value of 0.33 € per kg. Reduced feed intake is also a parameter included and calculated with 0.4 kg less feed intake for every kg MY reduction. These two factors are the same for both severe and the veterinary treatment case. Factors that differ are the veterinary cost, discarded milk, and extra labor.

In the veterinary treated case the costs are divided into fixed and variable veterinary costs, medicine and the cost for acute claw trimming. The price for claw trimming is the same in both cases of SU, but they have not the same valued. The value for the veterinary treatment case is 0.5 while the value in the severe case is 1. This leads to a lower price in the veterinary treated case than in the severe case. Herdsperson´s labor is calculated with a factor 4 hours and 5 minutes in the severe case. In the other case the time is calculated to 5 hours and 33 minutes. An hour is worth 22 € in both cases. The factor consists of several parts in the veterinary treated case which has been put together, different subfactors are for example the extra own work at the farm, extra time for disrupted routines, time with veterinarian and also with the claw trimmers.

Oskarsson (2010) did also calculate factors and costs for DD. The different factors were veterinary treatment cost, herdsperson´s labor and reduced MY. Veterinary treatment cost consists of a treatment with Cyklospray at a cost of 5.50 €. The calculation shows the reduced MY to be 200 kg and the value per kg was sat to 0.33 €. In association to the reduced MY the feed intake is also decreased. For every kg less MY the animals were assumed to consume 0.4 kg less. The treatment in DD has a factor 0.5 and a value on 11 €. The herdspersons labor has a factor 0.5 hours and a value on 22 €.

Table 4: Cost of health disturbances in dairy cows

Type of hoof disease

SU with Veterinairy treatment

SU (severe)

DD

Proportion of lesions %

Missing

Missing

Missing

Direct costs (€):

 

 

 

Veterinary treatment - labor, blocks and drugs

117.59

82.5

5.5

Herdsperson´s labor

122.1

99

11

Milk Withdrawal

79.2

Missing

Missing

Reduced yield

125.4

165

66

Reduced feeding cost

-22

-22

-8.8

Total

422.29

324.5

73.7

Indirect costs (€):

 

 

 

Increased culling

Missing

Missing

Missing

Extended calving interval (fertility)

Missing

Missing

Missing

Extra services (fertility)

Missing

Missing

Missing

Total

Missing

Missing

Missing

Total cost of a single limb case (direct and indirect costs)

422.29 

324.5

73.7

Cost of repeat cases per affected cow and year

Missing

Missing

Missing

 Direct cost for a lame cow per year single limb case plus recurrence

Missing

Missing

Missing

Total cost for a lame cow per year single limb case plus recurrence

Missing

Missing

Missing

Source: (Oskarsson, 2010) Calculations with the exchange rate from 11/17/2011 from (SKR) to (€).

Interview

In order to get a grasp of the economic impact that hoof diseases may have for the farmers today, but also in the future, two interviews with two Danish hoof experts were made. An E-mail contact was established with Jehan Ettema, Consultant at SimHerd A/S. And a telephone interview was also made with Finn Strudsholm, senior consultant at AgroTech.

Ettema (2011) thinks a case of horn diseases (SU for example) is more expensive than a single case of DD at present. Due to DD's high prevalence he believes that this disease is affecting the farmer’s economy most. Strudsholm (pers. com. 2011) believes that DD together with lameness is going to be the most economic important hoof disease for the Danish farmers in the future. To prevent hoof diseases Ettema (2011) explains that some interesting results have been found with hoof washing machines. For the horn diseases he thinks that it is extremely difficult to prevent. Good trimming always pays off, he think that it is hard to conclude what is the cause and what the effect is going to be. Strudsholm (pers. com. 2011) emphasize the importance of having dry and clean hooves and therefore it is important with good mechanical solutions like scrapers and good hoof trimming. For the future Ettema (2011) discuss the best economic prevention method of foot diseases would be improved treatment and prevention like better nutrition, floors and hoof washing. Strudsholm (pers. com. 2011) also stresses that breeding and genetic selection also is going to be a tool in the future. When questioning Ettema (2011) about if he thought that new methods have to be developed, he replied that new methods for the future always will be required.

HOOF HEALTH, EFFECT ON MILK YIELD AND VISITS TO AMS AT KUNGSÄNGEN RESEARCH CENTER

Our hypothesis is that cows with hoof problems are less willing to visit the FA and milking unit and therefore have longer MI and fewer visits to the FA which will result in lower MY. Cows with hoof problems are also likely to be lower ranked and are hypothesized to spend longer time waiting in the HA.

MATERIAL AND METHODS

Study population

Data was collected from 206 Swedish Red and White cattle (SRB) at Kungsängens research farm (Swedish University of agricultural science) in Uppsala, Sweden. All the cows in the study had calved between the years 2003-2009. Table 5 shows the average herd values for the analyzed parameters in the study.

Table 5. Average herd values for cows in parity 1 and 2 in period 1 (lactation weeks 2-10), 2 (lactation weeks 11-20) and 3 (lactation weeks 21-30).

Recording of data

Data regarding daily milk yield (kg), milking interval (MI) (h), number of visits to the FA, and the time spent in the HA and FA (min) was obtained from Kungsängens research farm. The analysis includes data from the housing period (15th of September to 15th of May) during the years of 2006-2011. Data regarding the incidence of HHE, H and Any Lesions (AL) (interdigital hyperplasia, H, HHE, eczema, foot rot and ulcers) was obtained from claw health status protocols received from routine claw trimming. The prevalence reflects how many cows on average that ha a remark at the trimming occasions. The disorders were chosen since they were considered to be the most common disorders, causing most problems, in dairy production. The trimming was performed three times a year; one month before grazing period i.e. in April, at intake in October and around New Year. Trimming was performed by a professional claw trimmer and the same claw trimmer was recruited at every trimming. On average 36.2 cows were trimmed at every trimming occasion, ranging from 24 to 49. The cows were housed in a loose housing system with a voluntary milking system (VMS) from DeLaval with capacity for maximum 54 cows. The HA connected to the milking unit, was closed, i.e. the cows who had entered the HA had to be milked in order to enter the stall again.

Data handling and statistical analysis

The analysis includes information on cows in lactation number one and two and was restricted to information about lactation weeks 2 to 30. Lactation weeks were for the analyses grouped into three periods. Period 1 included lactation weeks 2-10, period 2 lactation weeks 11-20 and period 3 lactation weeks 21-30. When these limitations had been considered, information about 206 cows with information about lactation weeks 1-58 remained. Information on 4494 lactation weeks was included in the analysis. Three 0/1-codes based on information from claw trimming protocols were considered in the statistical analyses for HHE, H and AL. The cows were affixed to number 0 or 1 according to the status of the hoof health from the claw trimming. Cows affixed to number 0 had no remarks for HHE, H or AL while cows affixed to number 1 had one or several remarks. This coding was valid three weeks before, two weeks after and during the week that the trimming was performed. The remaining weeks, the cows were affixed to code 99. The statistical analysis included a variance analysis (PROC MIXED) and was performed by using the statistic program SAS (SAS Inst. Inc., Cary, NC). The statistic model included the fixed effects of lactation number, lactation period, lactation week nested within lactation period and the code for hoof health from claw trimming. The interaction between lactation number and hoof health code and the interaction between lactation period and hoof health code were also included. The random effect of the cow was included in the model and least-squares-means were calculated for the fixed effects.

RESULTS

Heel horn erosion

The average prevalence of HHE during the total period of measurements was 39.9 % (Table. 9, Appendix). In average, 39 % of the first parity cows, 36 % of the second parity cows and 43 % of the cows in third parity or later had HHE (Table. 10, Appendix). Of the cows that had been trimmed 3-6 times during the analyzed period, 10 (15 %) cows had a remark on hoof health at every trimming occasion and 95 % of these remarks were HHE. Of the 56 % of the remarks on the 22 cows that had remarks on hoof health at 45-99 % were HHE and 25 % of the remarks on cows the 24 cows that had remarks on hoof health at 1-44 % were HHE (Table 11).

Effect of HHE and effect of interaction between parity or lactation period and HHE on MY, number of visits to the FA per day, and time in HA as well as S2 for MI and number of visits to FA is presented in Table 12, Appendix. The diagnosis of HHE and the interaction between lactation period and HHE had no significant effect on daily MY.

MI was not significantly affected by the incidence of HHE. Cows with HHE visited the FA significantly more often than cows without HHE.

Haemorrhages

The average prevalence of H during the total period of measurements was 13.2 % (Table. 9 Appendix). On average 20 % of first parity cows, 7 % of second parity cows and 11 % of the cows in third parity or later had H (Table. 10 Appendix). Of the cows that had been trimmed 3-6 times during the analyzed period and had any remark on every occasion 24 % of the remarks were for H. Of the cows that had any remark on hoof health at 45-99 % of the trimming occasions, 15 % of the remarks were H and 4 % of the remarks on cows that had any remark on hoof health at 1-44 % of the trimmings were H (Table 11).

Effect of H and the effect of interaction between parity or lactation period and H on MY, MI, number of visits to the FA per day, time in FA and time in HA as well as S2 for milking intervals and number of visits to FA is presented in Table 13, Appendix. Daily MY was significantly affected by the incidence of H as well as by the interaction between stage of lactation and H. Cows without H had on average 1.7 kg higher daily MY compared to cows with H and the effect was consistent throughout the entire lactation. The occurrence of H had no significant effect on MI.

Cows with H visited less frequently and spent lesser time per day in the FA than cows without H. Moreover, the results indicate that cows with H spent somewhat more time per day waiting in the HA before milking compared to cows without H.

Any lesions

The average prevalence of AL during the total period of measurements was 52.2 % (Table. 9 Appendix). On average 49 % of the first parity cows, 42 % of the second parity cows and 49 % of the cows in third parity or later had AL (Table. 10 Appendix). The average incidence of eczema, IH and ulcers in the herd was 5.5 %, 1.1 % and 1.8 % respectively. No cases of DD or foot rot were observed. Twelve of the cows that were trimmed 3-6 times during the analyzed period did not have any remarks at all.

Effect of AL and effect of interaction between parity or lactation period and AL on MY, MI, number of visits to the FA per day, time in FA and time in HA as well as S2 for milking intervals and number of visits to FA are presented in Table 14, Appendix.

Daily MY or MI were not significantly affected by the occurrence of AL. However, cows with AL visited the FA significantly higher amount of times per day compared to cows without AL.

DISCUSSION

Generally hoof disorders in intensive dairy productions are a relevant and increasing problem all over the world. This might be due to increased use of loose housing system which facilitates increased spread of contagious diseases as well as increased hoof wear and exposure to manure. Also, the development towards larger and higher yielding cows might contribute to elevated hoof problems. Digital dermatitis has increased most markedly, perhaps due to its contagious nature. Further, the trend towards lager herds might also contribute to increased hoof problems (Cramer et al., 2008; Wells et al., 1999; Whitaker et al., 2000). However, one can speculate that the effect of herd size per se, probably do not have an impact on the occurrence of hoof disorders. Rather, factors affected by herd size are the actual causes. A larger herd might be associated with higher stocking density, lesser time spent per cow and purchasing of animals, which in turn can result in poorer hoof health; hence a herd size suitable for the housing and management conditions of the farm is essential.

Many risk factors have been suggested to have an impact on the development of hoof disorders. However, the complexity of casual mechanisms behind the conditions discussed in this review makes it hard to define specific risk factors but according to Strudsholm (pers. com., 2011) bad hoof health can be prevented by correct management, which also is indicated by the huge variation in claw health between herds in the same systems. Strudsholm states that there is enough knowledge on how to prevent bad hoof health and that those farmers who apply this knowledge generally do not have any problems. Good management includes proper environmental conditions in terms of comfortable lying areas, stocking density, removal of manure and effluents, exercise and regular claw trimming. A clean and dry environment is one of the most important preventive factors (pers. com. Strudsholm, 2011) and a sufficient removal of manure is of great importance, especially in loose housing systems. However, as mentioned above, too frequent scraping with existing solutions for manure cleaning can be detrimental to the hooves. Hence, development of even more effective and non-damaging manure systems would be of interest to the farmer. One solution could be to use slatted instead of solid floors and studies have shown that slatted floors decrease the risk of DD (Somers et al., 2003; Somers et al., 2005a) and HHE (Somers et al., 2005c) compared to solid concrete floors. The positive effects of slatted floors are confirmed by Strudsholm (pers. com., 2011).

A good program for hoof trimming is also of major importance in order to prevent development of hoof disorders (Holzhauer et al., 2005; Somers et al., 2005a). Therefore it is of great interest for the farmer to find an optimal economic solution for this. In Denmark and Sweden, it is becoming common for large scale dairy farmers to have their own trimming facilities and to have educated hoof trimmers among the staff (pers. com. Strudsholm, 2011; pers. com., Hallén Sandgren, 2011). This could in the near future also be adopted by a large proportion of dairy producers all over the world and therefore an increased demand for education and tools for hoof trimming could be expected.

Soft mattresses are favorable in order to provide a comfortable lying area and decrease the risk of hoof disorders (pers. com Hallén Sandgren, 2011) Also, the use of sand as bedding material as well as deep straw beddings are becoming more common all over the world (pers. com., Hallén Sandgren, 2011) and has shown to have positive effects on the reduction of hoof problems (pers. com., Strudsholm, 2011) due to increased lying times (pers. com., Hallén Sansgren, 2011). Hence, investing in development of products to facilitate the handling of sand or deep litter systems might be profitable for the companies producing dairy equipment.

Since the occurrence of one hoof disorder can make cows more susceptible to other hoof disorders (Holzhauer et al., 2005), it is of major importance to prevent development of diseases at an early stage. Hence it is important to build the stalls correctly and with good solutions right from the start. This is also of economic interest since it is very expensive to rebuild the stables. Also extra attention should be paid to freshly calved cows, since these are more susceptible to hoof disorders.

The effect of foot-baths on the development of DD differs in different reports (Holzhauer et al., 2006; Rodriguez-Launz, 1999). According to Strudsholm (pers. com., 2011) foot-baths can even make more damage than good since it makes the hooves wet. Also the chemicals used are a threat to the environment. Thus, it would be of great interest to find a product that cleans the hooves without making them wet or a product that dries the hooves after cleaning them.

Breeding for animals with good hoof and leg health is important in order to prevent hoof diseases. By increasing the importance of hoof health in breeding programs it is possible to increase resistance against specific hoof disorders. Further, genomic selection might facilitate this possibility even more in the future (pers. com., Strudsholm, 2011). The heritability of resistance against hoof disorders is suggested to be important also in our own study were the ten cows that had one or several remarks at every claw trimming also stood for the highest prevalence for all investigated diseases, except foot rot which was not present at all. Further, some cows trimmed 3-6 times, did not have any remarks at any of these trimming occasions which further states the suggestion that good hoof health could be selected for.

Another possible way to reduce the development of most hoof disorders is to prolong the grazing period. Given the right conditions, the environment at pasture is less slurry and mild stages of HHE can heal spontaneously. Thus, a prolonged grazing period is good for both prevention and curing of the disease. However, one can speculate that during rainy seasons, the wet condition could be detrimental to the hoof health. Also, in Nordic countries, the grazing season are somewhat limited which makes this suggestion hard to apply.

Since higher intake of roughage makes the manure more compact, it is important to have a balanced concentrate and roughage ratio. This also decreases the risk of development of rumen acidosis, resulting in reduced risk of lameness. However, this might be a problem in high producing cows since this might lead to an insufficient energy intake, resulting in increased risk of negative energy balance and reduced milk yield. Further, negative energy balance might increase the risk of developing other diseases which in turn increases the risk of developing lameness.

With increasing herd size, cows with hoof problems are harder to detect and hence a tool for detection of affected cows would be of interest. These cows could maybe be detected by deviations in MI which could be alarmed by the VMS. Another way to detect cows with claw problems could be to use some kind of activity registration in order to detect cows with reduced activity which might be caused by hoof problems. Also a weighing floor in the VMS could be used to detect continuous unloading of one or several hooves. Since there seems to be enough knowledge about how to prevent hoof disorders and the problems differ between herds, specific consultant programs might be a way to incorporate the knowledge to the herds and to design specific intervention programs.

According to the economic calculations in this project, the most expensive hoof disease is SU. Hence, since SU is mainly caused by mechanical stress, investments in reducing these risk factors are of great importance. According to Cha et al. (2010) the expensive outcome of SU can be explained by reduced milk yield. The calculations made by Kossaibati et al. (1999) and Esslemont & Kossaibati (2002) show that treatment costs (veterinary treatment and extra labour) as well as the indirect costs are higher for SU than for any other disease. Oskarsson (2010) indicated that reduced milk yield and treatment costs are the most economic important factors for SU. According to Kossaibati et al. (1999) and Cha et al. (2010) treatment are the most costly factor for DD. On the contrary Esslemont & Kossaibati (2002) and Oskarsson (2010) showed that reduced MY is the most costly factor for DD. In most cases, the indirect costs for hoof diseases were higher than the direct costs (Kossaibati et al., 1999 and Esslemont & Kossaibati, 2002).

The prevalence of SU is rather low and decreasing while the prevalence of DD is rather high and increasing which could make DD cause more economic damage than SU in a herd with high prevalence of DD, even though SU cost more per case than DD. To get a grasp of the cost related to the prevalence of different hoof diseases within herd level some examples have been calculated. The prevalence of DD on cow level has in North America, Denmark and Netherlands in recent years been 20 – 35 % (Somers et al., 2003; Holzhauer et al., 2006; Capion et al., 2008; Cramer et al., 2008; Nielsen et al., in press). According to American calculations the cost of one case of DD in one single limb, including indirect costs, is 98.67 € (Cha et al., 2010). In a 100-cow herd this means a total cost of 1973 € (20 %) or 3453 € (35 %). In recent years the prevalence of SU has varied between 4 and 10 % in most of the investigated countries (Somers et al., 2003; Van der Waai, 2005; Capion et al., 2008; Cramer et al., 2008; Kujala et al., 2009). The cost of one case of SU in one single limb, including indirect costs is 160.33 € (Cha et al., 2010). In a 100-cow herd this means a total cost of 641.32 € (4 %) or 1282.64 € (10 %). This means that since the prevalence of DD is higher in many herds, the herd specific costs for claw disorders could be higher for DD than for SU. This also proves Ettemas (2011) thesis that DD has the biggest economic impact of the different hoof diseases.

It is hard to compare different calculations for hoof health since the factors included in the studies are not the same. The fact that the calculations are made during different years and with different inflation calculations in different countries also contributes to different costs for factors and thereby different results.

The results from the analyzed claw lesion data from Kungsängen is somewhat inconsistent and do not show the significant effects that we expected. This might be because the hoof health protocols used in the study also includes the disorders that are not severe enough to cause pain and behavioral changes to the cow. For more significant results, protocols from cows with veterinary treated cases of hoof disorders could be used. In general, the herd at Kungsängen had a fairly good hoof health situation, with no cases of DD or foot rot. The fact that the prevalence of AL seemed to be rather high but that the numbers of cows that were actually affected by their lesions were rather low can indicate that the farm has a good identification level of lame cows.

The prevalence of HHE in the study is however consistent with the results from the Swedish study by Manske (2002), where the prevalence of HHE was 41 %. These prevalence values are on the contrary much higher than the values obtained in the other reviewed studies (e.g. Cramer et al., 2008; Fjeeldas et al., 2011). However, these results depends a lot on claw trimmers perception of the disease, hence comparison of studies might not be relevant.

In our study, cows with HHE or AL visited the FA more times per day compared to unaffected cows. Also, cows with HHE visited the FA for a shorter period compared to cows without HHE. This might be due to the fact that cows with hoof problems might be lower ranked compared to unaffected cows (pers. com. Pettersson, 2011) and the lower ranked cows might have been pushed away from the feeding troughs by higher ranked cows. It could also be explained by the fact that active cows, which tend to walk around more than other cows might get more HHE and AL of hygienic background but of minor importance. Another reason could be that the pain caused by HHE or AL was not strong enough to prevent the cows from going to the FA. However, the pain might have grown stronger while the cow was standing, forcing the cow to leave the FA to be able to lie down. Since there are different levels of HHE, the pain level might differ between different cases which could be a reason for larger S2 for the time in FA for cows with HHE compared to without HHE.

The failure of finding significantly negative results for HHE and AL might be due to the fact that these lesions might occur in different levels that not all cause pain enough to cause behavioral changes. However, H might cause pain at an earlier stage than HHE and AL which could explain the more significant and expected results for the effect of H on MY. This might also explain the more logical result on number of visits to and the time spent in the FA. Cows with H, visited the FA fewer times per day and for a shorter period. This might suggest that these cows had a lower feed intake, which could explain the reduction in MY. These results indicate that H might be the most severe hoof disorder in dairy production and that the condition negatively affects both animal welfare as well as the economy of the production. Thus preventive interventions and special attention of H is of great importance. The results indicate that cows with H spend more time in the HA than cows without H. This confirms our hypothesis that cows with hoof problems spends more time waiting in the HA because of a lower rank in the herd and that this might be a predisposing factor for the disease.

CONCLUSIONS

Bad hoof health is an increasing and expensive problem in intensive dairy productions all over the world. Preventive interventions are important in order to obtain a sustainable production, both from an economical and animal welfare aspect. Hoof disorders are possible to prevent by a correct management and early detection of affected animals, regular claw trimming and a clean and dry environment is essential. Investment in prevention of hoof disorders is therefore profitable for the farmer.

AUTHORS

Emelie Carlsson

Alexander Falk

Elisabet Germundson

Niina Kangas

Carolina Markey

Helena Oscarsson

Caroline Robertsson

from Swedish Univeristy of Agricultural Sciences, SLU, as an Agrosystem project

REFERENCES

Agenäs, S. Assistant professor, Swedish university of agricultural science. Sweden. Personal message, 2011-10-03.

Alban, L. (1995). Lameness in Danish dairy cows: frequency and possible risk factors. Preventive Veterinary Medicine, vol. 22, pp. 213-225.

Alban, L., Agger, J. F. & Lawson, L. G. (1996). Lameness in tied Danish dairy cattle: the possible influence of housing systems, management, milk yield and prior incidence of lameness. Preventive Veterinary Medicine, vol. 29, pp. 135-149.

Amory, J.R., Barker, Z.E., Wright, J.L., Mason, S.A., Blowey, R.W. & Green, L.E. (2008). Associations between sole ulcer, white line disease and digital dermatitis and the milk yield of 1824 dairy cows on 30 dairy cow farms in England and Wales from February 2003–November 2004. Preventive Veterinary Medicine, vol. 83, pp. 381–391.

Andersson, L. (1982). Klövar Om klövvård och klövsjukdomar. 3. Ed. Hållsta. SHS Text och tryck service.

Bergsten, C. (1993) Causes, Risk Factors, and Prevention of Laminitis and Related Claw Lesions. Acta veterinary Scandinavia, vol 98, pp.157.156.

Bach, A., Dinarés, M., Devant, M. & Carré, X. (2007). Associations between lameness and production, feeding and milking attendance of Holstein cows milked with an automatic milking system. Journal of Dairy Research, vol. 74, pp.40-46.

Barker, Z. E., Amory, J. R., Wright, J. L., Mason, S. A., Blowey, R. W. & Green, L. E. (2008). Risk factors for increased rates of sole ulcers, white line disease, and digital dermatitis in dairy cattle from twenty-seven farms in England and Wales. Journal of Dairy Science, vol. 92, pp. 1971-1978.

Bank of England. Inflation Calculator. (14 November 2011) [online]. Available from: http://www.bankofengland.co.uk/education/inflation/calculator/index1.htm [14 November 2011].

Barker, Z.E., Leach, K.A., Whay, H.R., Bell, N.J. & Main, D.C.J. (2010). Assessment of lameness prevalence and associated risk factors in dairy herds in England and Wales. Journal of Dairy Science, vol. 93, pp. 932-941.

Biefeldt, J. J., Badertscher, R., Tölle, K. H. & Krieter, J. (2005). Risk Factors influencing lameness and claw disorders in dairy cows. Livestock Production Science, vol. 95, pp. 265-271. Borderas, T. F., Fournier, A., Rushen, A & de Passillé, A. M. (2007). Effect of lameness on dairy cows’ visits to automatic milking systems. Canadian Journal of Animal Science, vol. 88, pp. 1-8.

Blowey, R. (2005). Factors associated with lameness in dairy cattle. Farm Animal Practice, vol. 27, pp. 154-162.

Brown, C. C., Kilgo, P. D. & Jacobsen, K. L. (2000). Prevalence of Papillomatous Digital Demratitis among culled adult cattle in the southeastern United States. American Journal of Veterinary Research, vol. 8, pp. 928-930.

Capion, N., Thamsborg, S.M. & Enevoldsen, C. (2008). Prevalence of foot lesions in Danish Holstein cows. Veterinary Record, vol. 163, pp. 80-86.

Cha, E., Hertl, J.A., Bar, D & Gröhn, Y.T. (2010). The cost of different types of lameness in dairy cows calculated by dynamic programming. Preventive Veterinary Medicine, vol. 97, pp. 1-8.

Cheli, R. & Mortellaro, C. (1974). La dermatite digitale del bovino. Proc. Of the 18th Int. Meeting on diseases of cattle, Milan, pp 208-213.

Clarkson, M.J., Downham, D.Y., Faull, W.B., Hughes, J.W., Manson, F.J., Merritt, J.B., Murray, R.D., Russel, W.B., Sutherst, J.E. & Ward, W.R. (1996). Incidence and prevalence of lameness in dairy cattle. The Veterinary Record, vol. 138, pp. 563-567.

Cook, N.B. (2003). Prevalence of lameness among dairy cattle in Wisconsin as a function of housing type and stall surface. Journal of American Veterinary Medical Association, vol. 9, pp. 1324-1328.

Cramer, G., Lissemore, K.D., Guard, C.L., Leslie, K.E. & Kelton, D.F. (2008). Herd and Cow level Prevalence of Foot Lesions in Ontario Dairy Cattle. Journal of Dairy Sciences, vol. 91, pp. 3888-3895.

Cramer, G., Lissemore, K. D., Guard, C. L., Leslie, K. E. & Kelton, D. F. (2009). Herd-level risk factors for seven different foot lesions in Ontario Holstein cattle housed in tie stalls or free stalls. American Dairy Science Association, vol. 92, pp. 1404-1411.

Envoldsen, C., Gröhn, Y. T. & Thysen, I. (1991). Sole ulcer in dairy cattle: associations with season, cow characteristics, disease and production. Journal of Dairy Science, vol. 74, pp. 1284-1298.

Espejo, L.A., Endres, M.I. & Salfer, J.A. (2006). Prevalence of Lameness in High-Producing Holstein Cows Housed in Frestall Barns in Minnesota. Journal of Dairy Sciences, vol. 89, pp. 3052-3058.

Esslemont, D. & Kossaibati, M. (2002). The costs of poor fertility and disease in UK dairy herds. Trends in DAISY herds over 10 seasons: DAISY research report no. 5. Published by Intervet UK Limited, Milton Keynes, UK. ISBN 0-9540013-1-1.

Ettema, J. Consultant, SimHerd, Denmark. Personal message, 2011-11-28.

Faye, B. & Lescourret, F. (1989). Environmental factors associated with lameness in Dairy cattle. Preventive Veterinary Medicine, vol. 7, pp. 267-287.

Fjeldaas, T., Sogstad, Å.M. & Østerås, O. (2011). Locomotion and claw disorders in Norwegian dairy cows housed in freestalls with slatted concrete, solid concrete or solid rubber flooring in the alleys. Journal of Dairy Science, vol. 94, pp. 1243-1255.

Frankena, K., Stassen, E.N., Noordhizen, J.P., Goelema, J.O., Schipper, J., Smelt, H & Romkema, H. (1991). Prevalence of lameness and risk indicators for dermatitis digitalis (mortellaro disease) during pasturing and housing of dairy cattle. In: Thrusfield, M.V. (Ed.) Society for veterinary epidemiology and preventive medicine. Proceedings of a meeting held at the University of London the 17th, 18th and 19th of April 1991.

Frankena, K., van Keulen, K.A.S., Noordhuizen, J.P., Noordhuizen-Stassen, E.N., Gundelach, J., de Jong, D.J. & Saedt, I. (1992). A cross-sectional study into prevalence and risk indicators of digital haemorrhages in female dairy calves. Preventive Veterinary Medicine, vol. 14, pp. 1-12.

Groehn, J. A., Kaneene, J. B. & Foster, D. (1992). Risk factors associated with lameness in lactating dairy cattle in Michigan. Preventive Veterinary Medicine, vol. 14, pp. 77-85.

Green, L. E., Hedges, V. J. & Schukken, Y. H. (2002). The impact of clinical lameness on the milk yield of dairy cows. Journal of Dairy Science, vol. 85, pp. 2250-2256.

Gustafson, G. M. (1993). Effects of daily exercise on the health of tied dairy cows. Preventive Veterinary Medicine, vol. 17, pp. 209-223.

Hallén Sandgren, C. DeLaval. Personal message, 2011-12-20.

Hedges, J., Blowey, R.W., Packington, A.J., O’Callaghan, C.J. & Green, L.E. (2001). A Longitudinal Field Trial of the Effect of Biotin on Lameness in Dairy Cows. Journal of Dairy Science, vol. 84, pp. 1969-1975.

Holzhauer, M., Hardenberg, C., Bartels, C.J.M. & Frankena. K. (2006). Herd- and Cow-Level Prevalence of Digital Dermatitis in The Netherlands and Associated Risk Factors. Journal of Dairy Science, vol. 89, pp. 580-588.

Holzhauer, M., Hardenberg, C. & Bartels, C. J. M. (2008). Herd and cow-level prevalence of sole ulcers in the Netherlands and associated-risk factors. Preventive Veterinary Medicine, vol. 85, pp. 125-135.

Hultgren, J., Manske, J.& Bergsten, C. (2004) Associations of sole ulcer at claw trimming with reproductive performance, udder health, milk yield, and culling in Swedish dairy cattle. Preventive Veterinary Medicine 62, 233-251.

Johannesson P. (2003) Miljö- och skötselfaktorer som påverkar förekomsten av klövröta hos svenska mjölkkor. Examensarbete. Skara, Sveriges Lantbruksuniversitet. ISSN 1650-7045.

Kossaibati, M.A., Esslemont, R.J. & Watson,C. (1999). The Costs of hoof diseases in Dairy Herds. In: The National Cattle Hoof diseases Conference, Stoneleigh, Warwickshire.

KRAV (2011). Regler for KRAV-certifierad produktion januari 2011[online]. Available from http://www.krav.se/Documents/Regler/utgavor/KRAVsreglerUgavaJanuari2011.pdf. [2012-01-02].

Kremer, P. V., Nueske, A. M. & Foerster, M. (2006). Comparison of claw health and milk yield in dairy cows on elastic or concrete flooring. American Dairy Science Association, vol. 90, pp. 4603-4611.

Kujala, M., Dohoo, I.R., Laakso, M., Schnier, C. & Soveri, T. (2009). Sole ulcers in Finnish dairy cattle. Preventive Veterinary Medicine, vol. 89, pp. 227-236.

Manske T. (2002). Hooflesions and lameness in Swedish Dairy Cattle. Doctoral thesis. Skara: Swedish University of Agricultural Sciences.

Manske, T., Hultgren, J. & Bergsten, C. (2002a). Prevalence and interrelationships of hoof lesions and lameness in Swedish dairy cows. Preventive Veterinary Medicine, vol. 54, pp. 247-263.

Manske, T., Hultgren, J. & Bergsten, C. (2002b). Klövvård och klövhälsa hos mjölkkor. Jordbruksinformation 4-2002. Jordbruksverket. ISSN: 1102-8025.

Murray, R.D., Downham, D.Y., Clarkson, M.J., Faull, W.B., Hughes, J.W., Manson, F.J., Merritt, J.B., Russell, W.B., Sutherst, J.E. & Ward, W.R. (1996). Epidemiology of lameness in dairy cattle: description and analysis of foot lesions. The Veterinary record, vol. 138, pp. 586-591.

Nielsen, B.H., Thomsen, P.T., Green, L.E. & Kaler, J. (In press.). A study of the dynamics of digital dermatitis in 742 lactating dairy cows. Preventive Veterinary Medicine vol. xxx, pp. xxx– xxx.

Onyiro, O. M., Andrewsm, L. J. & Brotherstone, S. (2008). Genetic parameters for digital dermatitis and correlations with locomotion, production, fertility traits, and longevity in Holstein-friesian dairy cows. Journal of Dairy Science, vol. 91, pp. 4037-4046.

Oskarsson, M. 2010. Kostnader för hälsostörningar hos mjölkkor. Beräkningsunderlag till hälsopaket mjölk djurhälsokostnader. Stockholm, 2010.

Petterson, G. Swedish University of agricultural science. Personal message 2011-11-01.

Read, D. H. & Walker, R.L. (1998). Papillomatous digital dermatitis (footwarts) in California dairy cattle: clinical and gross pathologic findings. Journal of Veterinary Diagnostic Investigation, vol. 10, pp. 67-76.

Rodriguez-Lainz, A., Hird, D. W., Walker, R. L. & Read, D. H. (1996). Papillomatous digital dermatitis in 458 dairies. Journal of American Veterinary Medical Association, vol. 8, pp. 1464-1467.

Rodriguez-Lainz, A., Melendez-Retamal, P., Hird, D., W. Read, D. H., & Walker, R. L. (1999). Farm- and host level risk factor for papillomatous digital dermatitis in Chilean dairy cattle. Preventive Veterinary Medicine, vol. 42, pp. 87-97.

Rushen, J., de Passillé, A. M., Borderas, F., Tucker, C. & Weary, D. (2004). Designing better environments for cows to walk and stand. Advances in Dairy Technology, vol. 16, pp. 55.

Sanders, A. H., Shearer, J. K. & De Vries, A. (2009). Seasonal incidence of lameness and risk factors associated with thin soles, white line disease, ulcers, and sole punctures in dairy cattle. Journal of Dairy Science, vol. 92, pp. 3165-3174.

Singh, S. S., Ward, W. R., Lautenbach, K. & Murray, R.D. (1993). Behavior of lame and normal dairy cows in cubicle and in a straw yard. Veterinary record, vol. 133, pp. 204-208.

Sogstad, M., Fjeldaas, T., Østerås, O., & Plym Forshell, K. (2005a). Prevalence of claw lesions in Norwegian dairy cattle housed in tie stalls and free stalls. Preventive Veterinary Medicine, vol. 70, pp. 191-209.

Sogstad, M., Fjeldaas, T. & Østerås, O. (2005b). Lameness and Claw Lesions of the Norwegian Red Dairy Cattle Housed in Free Stalls in Relation to Environment, Parity and Stage of Lactation. Acta Veterinaria Scandinavica , vol. 46, pp. 203-217.

Somers, J. G. C. J., Frankena, K., Noordhuizen-Stassen, E. N. & Metz, J. H. M. (2003). Prevalence of claw disorders in Dutch dairy cows exposed to several floor system. Journal of Dairy Science, vol. 86, pp. 2082-2093.

Somers, J. G. C. J., Frankena, K., Noordhuizen-Stassen, E. N., Metz, J. H. M. (2005a) Risk factors for digital dermatitis in dairy cows kept in cubicle houses in the Netherlands. Preventive Veterinary Medicine 71, 11-21.

Somers, J. G. C. J., Frankena, K., Noordhuizen-Stassen, E. N. & Metz, J. H. M. (2005b). Development of claw traits and claw lesions in dairy cows kept on different floor systems. Journal of Dairy Science, vol. 88, pp. 110-120.

Somers, J.G.C.J., Frankena, K., Noordhuizen-Stassen, E.N. & Metz, J.H.M. (2005c). Risk factors for interdigital dermatitis and heel horn erosion in dairy cows kept in cubicle houses in the Netherlands. Preventive Veterinary Medicine, vol. 71, pp. 23-34.

Sprecher, D. J., Hostetler, D. E. & Kaneene, J. B. (1997). A lameness scoring system that uses posture and gait to predict dairy cattle reproductive performance. Theriogenology, vol. 47, pp. 1179-1187.

Strudsholm, F. Senior consultant, AgroTech, Denmark. Personal message, 2011-11-23.

Svensk Mjölk. Homepage. . [online] (8 December 2011) Available from http://www.svenskmjolk.se/Mjolkgarden/Djurhalsa/Klovhalsa/ [8 December 2011].

The Alberta Dairy Hoof Health Project. Hoof health overview. (20 December 2011) [online]. Available from: http://www.hoofhealth.ca/Section2/Index2.html [20 December 2011].

Tranter, W. P., Morris, R. S., Dohoo, I. R. & Williamsson, N. B. (1993). A case-control study of lameness in dairy cows. Preventive Veterinary Medicine, vol. 15, pp. 191-203.

Valuta.se. Homepage. [online] (28 November 2011) Available from http://www.valuta.se [28 November 2011].

Van der Waaij, E.H., Holzhauer, M., Ellen. E., Kamphuis, C. & de Jong, G. (2005). Genetic parameters for claw disorders in Dutch dairy cattle and correlations with conformation traits. Journal of Dairy Science, vol. 88, pp. 3672-3678.

Vink, D. (2004) Bovine digital dermatitis. In: Veterinary trust for continuing professional development conference, Stirling, 2004, 47-61.

Watson, C. (2007). Lameness in cattle. Wiltshire, UK: The Crowood Press ISBN: 978 1 86126 905 8.

Wells, S.J., Trent, A.M., Marsh, W.E. & Robinson, R.A. (1993). Prevalence and severity of lameness in lactating dairy cows in a sample of Minnesota and Wisconsin herds. Journal of American Veterinary Medical Association, vol. 1, pp. 78-82.

Wells, S.J. Garber, L.P. & Wagner, B.A. (1999). Papillomatous digital dermatitis and associated risk factors in US dairy herds. Preventive Veterinary Medicine, vol. 38, pp. 11-24.

Whitaker, D. A., Kelly, J. M. & Smith, S. (2000). Disposal and disease rates in 340 British dairy herds. Veterinary Record, vol. 146, pp. 363-367.

To see Appendix click here

Authors

Emelie Carlsson

Alexander Falk

Elisabet Germundson

Niina Kangas

Carolina Markey

Helena Oscarsson

Caroline Robertsson

from Swedish Univeristy of Agricultural Sciences, SLU, as an Agrosystem project

Abbreviations

AMS = Automatic Milking System, AL = Any Lesions, DD = Digital Dermatitis, FA = Feeding area, H = Haemorrhage, HA = Holding area, HHE = Heel horn erosion, IH = Interdigital Hyperplasia, MI = Milking interval, MY = Milk yield, NS = No significance, S2 = Standard deviation, SU = Sole ulcers, VMS = Voluntary Milking System.