Volume 99, Issue 8, August 2016, Pages 6494–6506
C.G.R. Nash*,
- * Department of Population Medicine, University of Guelph, Guelph, ON, N1G 2W1 Canada
- † Campbell Centre for the Study of Animal Welfare, University of Guelph, Guelph, ON, N1G 2W1 Canada
- ‡ Department of Animal Biosciences, University of Guelph, Guelph, ON, N1G 2W1 Canada
- § Département des Sciences Animales, Université Laval, Québec, QC, G1V 0A6 Canada
- # Animal Welfare Program, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, V6T 1Z4 Canada
- Received 23 November 2015, Accepted 23 April 2016, Available online 16 June 2016
Abstract
Leg
injuries on dairy cows are a common and highly visible welfare concern
on commercial dairy farms. With greater attention being placed on food
animal welfare and limited research being conducted on tiestall farms,
this study aimed to identify prevalence and risk factors for hock and
knee injuries on dairy cows housed in tiestall barns in Ontario (n = 40)
and Quebec (n = 60). A sample of 40 cows was purposively selected per
farm and several animal- and farm-based measures were taken. Both hocks
and both knees on each cow were scored as injured (presence of lesions
or swelling) or not injured (no alterations or hair loss), and the
highest score of each of the 2 knees and the 2 hocks was considered the
cow’s hock or knee score. Possible animal- and farm-based risk factors
were incorporated into 2 separate multivariable logistic models for hock
injuries and knee injuries respectively at the cow level. Mean (±SD)
percentage of cow with hock injuries per farm was found to be 56 ± 18%
and mean percentage of knee injuries per farm was found to be 43 ± 23%.
Animal-based factors found to be associated with a greater odds of hock
injuries at the cow level were increased days in milk (DIM), lower body
condition score (BCS), lameness, higher parity, higher cow width, median
lying bout duration, and median number of lying bouts. Environmental
factors found to be associated with hock injuries at the cow level were
province, stall width, tie rail position, stall base, chain length, and
age of stall base. Animal-based factors found to be associated with knee
injuries at the cow level were DIM, BCS, and median lying time.
Environmental factors found to be associated with knee injuries at the
cow level were stall width, chain length, province, stall base, and bed
length. Quadratic and interaction terms were also identified between
these variables in both the hock and knee models. This study
demonstrates that hock and knee injuries are still a common problem on
tiestall dairy farms in Canada. Several animal- and housing-based
factors contribute to their presence. Further research to confirm causal
relationships between these factors would help identify the cause of
knee and hock injuries and determine how to best reduce the incidence of
injuries in cows on commercial tiestall dairy farms in Canada.
Key words
- dairy cow;
- Canada;
- hock injury;
- knee injury;
- tiestall
© 2016 American Dairy Science Association®.
