Tail docking is a management tool that has been adopted and used mainly because of anecdotal evidence and perceived benefits in mastitis control. There is very little research available that supports claims of either advantages or disadvantages of tail docking. Two research studies were published recently in the Journal of Dairy Science, looking at different aspects of tail docking. While these articles do not resolve the question on whether tail docking should be adopted or not, they provide producers with more information to make an informed decision, based on the specific conditions on their own farms.
The first article is entitled 'Effects of Tail Docking Using a Rubber Ring With or Without Anesthetic on Behavior and Production of Lactating Cows" (E.M. Tom et al., J. Dairy Sci. 85:2257-2265). This article studied whether the use of anesthesia during the tail docking process is beneficial, in terms of milk production and animal behavior. Sixty-four lactating cows were split into groups of four treatments. They were: 1. rubber ring docking with epidural anesthetic, 2. rubber ring docking without epidural anesthetic, 3. control with epidural anesthetic and 4. control without epidural anesthetic. Cows in each treatment group were observed for behavioral changes 0, 1, 2 and 6 days after docking, as well as milk production and feed intake.
This study found no significant differences between the groups on either milk production or feed intake. Of the various behaviors that were observed in the cows, only a few showed any treatment differences. Cows that had their tails docked, regardless of whether they received anesthetic or not, shook their tails less, raised their tails less, and pressed their tails against their bodies more after the stump was amputated. The authors suggest that, based on these results, cows do not seem to benefit from anesthetic during tail docking and that cows seem to experience only mild discomfort at the procedure.
The second article is entitled 'Effects of Tail Docking on Milk Quality and Cow Cleanliness' (D.A. Schreiner & P.L. Ruegg J. Dairy Sci. 85:2503-2511). This study followed 1250 lactating dairy cows on eight farms, where cows were randomly assigned to tail docked or control groups. SCC, prevalence of intramammary infections (IMI, mastitis) and udder and leg cleanliness scores were monitored.
While significant differences in hygiene or milk quality were detected among farms, no significant differences could be found between tail docking treatments across all farms. However, three of the eight farms studied did experience significantly improved leg and/or udder hygiene scores with tail docking. On six of the eight farms, no effect of tail docking was noted on either leg and/or udder hygiene scores, while there were two instances where either leg and/or udder scores were poorer with tail docking. Across all eight farms studied, the authors could not detect any improvement in somatic cell count, udder or leg hygiene, prevalence of mastitis organisms, or milk quality that could be attributed to tail docking.
The November and December, 2002 issues of Journal of Dairy Science also carried articles the physiological and behavioral effects of the tail docking procedure, in this case with young animals.
The November issue carried the article entitled, 'Indicators of Acute Pain and Fly Avoidance Behaviors in Holstein Calves Following Tail-Docking' (S.D. Eicher & J.W. Dailey. J. Dairy Sci. 85:2850-2858). Twenty calves (3-5 weeks old) in two locations (ten per treatment) were assigned to either a docked or nondocked treatment group. Calves with docked tails were observed to have more activity directly following the banding procedure, more flies per leg and more fly avoidance behaviors than control calves. It was also found that the docked tail remained sensitive for up to 2 hours post banding. No differences between treatments were found in the two proteins these researchers chose as indicators of tissue trauma and stress. The bottom line was that while young calves seem to avoid the tissue trauma experienced by mature cows, they are more affected by the process of tail docking. The issue of increased flies is especially important in hutch environments, where calves of this age are often housed.
The second article, 'Responses to Tail Docking in Calves and Heifers' (D.A. Schreiner & P.L. Ruegg. J. Dairy Sci. 85:3287-3296), also supported the idea that calves aged 3-6 weeks tend to be more affected in their behavior responses than cattle of other ages, both younger and older. This body of evidence suggests that it may be beneficial to delay tail docking in calves, at least until they are no longer in the hutch environment.
The second article also examined the effects of tail docking on behavior and blood cortisol in pre-partum heifers. Heifers were assigned to four treatments: 1) cleaned tail, 2) cleaned and banded tail, 3) cleaned tail with epidural, 4) cleaned and banded tail with epidural. No significant differences were detected in any behaviors or in any stress indicators (cortisol levels, heart rate or body temperature).
This interaction of age and behavioral response to tail docking (and, perhaps, other management practices) deserves further attention.
Related Links:
A research paper from the University of California-Davis
A news bulletin from the Animal Welfare Department at the University of British Columbia
A veterinary science bulletin from Pennsylvania State University
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