The prevalences of Eimeria and Cryptosporidium in large Latvian cattle herds.

Eimeria and Cryptosporidium are common intestinal pathogens known to potentially cause long term effects to cattle health and production. This study aimed to document these parasites in Latvian cattle herds. From 16 dairy farms, 125 faecal samples were collected from animals aged 8–20 weeks. In addition, seven farmers completed a questionnaire aimed to assess their general knowledge on parasites, including questions regarding parasites and usage of anthelmintics, as well as grazing and housing practices, and occurrence of diarrhoea in calves. The faecal samples were examined for the presence of Eimeria oocysts using a McMaster technique and for the presence of Cryptosporidium oocysts with contrast staining of faecal smears. Eimeria species were differentiated morphologically. All herds were positive for Eimeria spp. and Cryptosporidium spp. was detected in 69% (95% CI 58-80) of them. Eimeria was found in 46% (95% CI 30-62) of individual samples with mean oocyst count of 7935 (SD 18022) per gram of faeces. Eight species were identified; E. zuernii and E. bovis were the predominant ones. Cryptosporidium was detected in 41% (95% CI 34-48) of examined animals but predominantly at low infection levels. Farmers, however, did not consider parasites as a problem. Combined low awareness among farmers, high infection pressure with Eimeria indicated by high oocyst counts of pathogenic species in most cases, and high herd-level prevalence of Cryptosporidium suggests that these parasites may be overlooked.