Effect of udder health management practices on herd somatic cell count
The farm management practices that most consistently have demonstrated to improve udder health and lower the somatic cell count are: wearing gloves during milking, using automatic take-offs, using post milking teat dipping, milking problem cows last, yearly inspection of the milking system, and use of a technique to keep cows standing following milking.
Other practices associated with lower SCC were the use of a free stall system, sand bedding, cleaning the calving pen after each calving, surveillance of dry-cow udders for mastitis, use of blanket dry-cow therapy, parenteral selenium supplementation, udder hair management, and frequent use of the California Mastitis Test. Regarding SCC of heifers, most of the consistent associations reported were related to interventions made during the peripartum period. Studies on automatic milking systems have frequently reported elevation of the herd SCC following transition to the new system. These elevations seemed to be mediated both by the lack of monitoring of chronically infected cows and by an elevated incidence of intramammary infections.
A group of Canadian mastitis experts has made a systematic review of the scientific literature on relationships between dairy farm management practices and herd somatic cell count (SCC). The aim was to distinguish those management practices that have been consistently shown to be associated with herd SCC from those lacking evidence of association. By assembling the results reported in many different studies, this review generates a more comprehensive understanding of the management practices influencing SCC and highlights areas of SCC control knowledge that lack evidence of effectiveness.
To be included in the review, a manuscript had to be published after 1979 in French, English, or Dutch; study design had to be other than case report or case series; herds studied had to be composed of ≥40 milking cows producing on average ≥7,000 kg of milk in 305 d; interventions studied had to be management practices applied at the herd level and used as udder health control strategies; and SCC had to be measured using electronic cell counting methods.
Practices demonstrating a consistent association with lower SCC:
• Wear gloves
• Postmilking teat disinfection
• Automatic take-off
• High SCC and/or clinical mastitis cows milked last
• Milking system inspected ≥ once/year
• Milking parlor cleaned regularly
• Cows locked after milking
• Housed in freestall
• Sand bedding
• Calving pen cleaned after each calving
• Udder checked for mastitis daily
• Blanket dry-cow treatment (vs. selective or none)
• Parenteral selenium supplementation
• Remove udder hair
• Use California Mastitis Test
Authors of review:
S. Dufour ,*†1 A. Fréchette ,* H. W. Barkema ,†‡ A. Mussell ,§ and D. T. Scholl *†
* Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, C.P. 5000, St-Hyacinthe, Quebec, J2S 7C6, Canada
† Canadian Bovine Mastitis Research Network, C.P. 5000, St-Hyacinthe, Quebec, J2S 7C6, Canada
‡ Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, 3300 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada
§ George Morris Centre, 225-150 Research Lane, Guelph, Ontario, N1G 4T2, Canada
J. Dairy Sci. 94 :563–579 doi: 10.3168/jds.2010-3715 © American Dairy Science Association®, 2011 .