[The most important parasitic intestinal infections in calves and their role in diarrheal diseases].

Various stock breeding herds in the USSR were examined for the presence of endoparasites. Coccidia of Cryptosporidium genus occurred in calves at the age of 3 to 4 days to one month, individually in older calves, too. Coccidia C. parvum infected the animals aged 14-15 days most frequently. Coccidia of Eimeria genus and intestinal round worm Strongyloides papilosus were registered sporadically in calves aged 13-15 days; most frequently they occurred in calves aged 1-2 months and older. Of the total number of the examined calves (aged 20 days), which were infected by Cryptosporidium, 77.7 resp. 89.8% were diarrhoeic. In cases of polyinfections with various species of coccidia of the Eimeria genus and S. papillosus, diarrhoea was recorded in 31.2% of one- to two-month-old calves. In cases of monoinfection with coccidia of the Eimeria genus diarrhoea was recorded in 15.8% of the calves, and in cases of infection with the intestinal worm S. Papillosus in 9.1% of the calves.