Porcine neonatal coccidiosis in quebec.

Intestinal coccidiosis was diagnosed in 110 diarrheic piglets originating from 66 farrowing operations. These piglets had been submitted alive for necropsy early after the beginning of diarrhea, and the diagnosis of coccidiosis was based on the demonstration of coccidial forms in their jejunum by histopathological examination. Enteropathogenic strains of Escherichia coli were demonstrated in only nine of the 110 piglets while the transmissible gastroenteritis virus and rotavirus were each present in three pigs. The most common lesion was a multifocal villous atrophy in the middle and lower jejunum, and ileum of the affected pigs. Coccidial forms were present in variable numbers of the cells lining the affected villi and they were mainly asexual stages (meronts and merozoites).In the affected farrowing houses diarrhea began between five and 15 days of age with the highest frequency around seven to ten days of age. Morbidity rates were very variable and mortality was less than 20%. The disease was a persistent problem in large farrowing operations on continuous farrowing programs, and losses were due mainly to retarded growth and treatment costs which were usually inefficient. The disease occurred year round with the highest prevalence in summer and fall months, and in January.Search for oocysts in fecal samples or colonic contents from 28 of the 110 pigs revealed that 13 of them were shedding oocysts identified as Isospora suis.