Canadian colleagues at three veterinary schools in Canada teamed up to do the first all-Canada survey to estimate the prevalence of MAP infected dairy herds. The study collected samples from 362 dairy herds in 10 Canadian provinces using environmental fecal cultures as the diagnostic test.
True prevalence estimates were 66% for farms in Western Canada, 54% in Ontario, 24% in Québec, and 47% in Atlantic Canada. Herds housed in tie-stalls had a lower prevalence than freestall-housed herds, and herds with 101–150 and >151 cows had higher prevalence than herds with ≤100 cows. This was the first time MAP prevalence was determined using 1 detection method, performed in 1 laboratory, and within a single year across Canada, enabling direct comparisons of prevalence among regions, housing types, and herd sizes.
This was the first time MAP prevalence was determined using 1 detection method, performed in 1 laboratory, and within a single year across Canada, enabling direct comparisons of prevalence among regions, housing types, and herd sizes. The authors did an elegant job of judging the sensitivity and specificity of their sampling method. Their survey findings are similar those done in Europe and a bit lower than estimates for U.S. dairy herds.