Prevalence of Giardia and Cryptosporidium in beef cows in southern Ontario and in beef calves in southern British Columbia

Abstract

In 1998 and 1999, fecal samples were collected from 669 beef cows on 39 farms located within 10 counties of Ontario. Overall prevalences of Giardia, Cryptosporidium muris, and Cryptosporidium parvum in cows were 8.7%, 10.6%, and 18.4%, respectively. Of the 39 farms sampled, Giardia was detected on 64%, Cr. muris on 72%, and Cr. parvum on 90%. Cryptosporidium parvum was detected in 28% of the cows in 1998 and in 5.2% in 1999. Differences between the 2 y were attributed to sampling during calving in 1998 and during gestation in 1999. In 1998, Giardia, Cr. muris, and Cr. parvum were detected in herds provided with municipal water. In 1998, 193 calves were sampled from 10 farms, representing 4 watersheds, in British Columbia. Thirty-six percent of the calves exhibited signs of diarrhea. Overall prevalences of Giardia and Cryptosporidium spp. in calves were 36% and 13%, respectively. There was evidence that calves with Giardia were more likely to develop scours. Restricting cattle from surface water during periods of high shedding may reduce watershed contamination.

Figure 1

Prevalence of Giardia spp. and Cryptosporidium spp. infections among beef cattle in southern Ontario sampled in 1998 and 1999. Prevalences were computed as the number of samples that were positive for Giardia spp. or Cryptosporidium spp. divided by the number of samples collected within each region, multiplied by 100. Within each agricultural region, the unenclosed percentage is the prevalence of Giardia infection, the value in parentheses ( ) is the prevalence of Cr. parvum, and that in square brackets [ ] is the prevalence of Cr. muris. (n) = total number of samples collected in the region over the 2 y. Bar = 100 km.

Figure 2

Prevalence of Giardia spp., Cryptosporidium spp., and Campylobacter jejuni infections among beef calves in southeastern British Columbia. Prevalences were computed as the number of calves infected with Giardia spp., Cryptosporidium spp. or Ca. jejuni divided by the number of calves sampled within each region, multiplied by 100. For each region, the unenclosed percentage is the prevalence of Giardia infection, the value in parentheses ( ) is the prevalence of Cryptosporidium infection, and that in square brackets [ ] is the prevalence of Campylobacter infection. (n) = total number of calves sampled in each region. Bar = 100 km.