The prevalence and intensity of infection with Eimeria species in sheep in Nyandarua district of Kenya.

The prevalence and numbers of coccidian oocysts in faecal samples from young (less than 6 months old), immature (6-12 months old) and adult (over 12 months old) sheep on 15 farms in Nyandarua district were studied during the dry and wet seasons. The species of Eimeria occurring in these sheep were also identified. The proportion of animals shedding coccidian oocysts did not vary significantly with season. The prevalence of the oocysts was significantly higher (p < 0.05) in young sheep (mean 85.3%) compared to immature (mean 40.2%) and adult sheep (mean 32.15%). OPG counts (oocysts per gram of faeces) were significantly higher (p < 0.01) in the young sheep compared to immature and adult sheep during both seasons. Prevalence and OPG did not differ between immature and adult sheep. There was no significant difference in OPG during the wet season (mean 328 +/- 997) compared to the dry season (mean 219 +/- 773). The sex of the sheep had no significant effect on prevalence or OPG. Eight species of Eimeria were recognized. They (and their prevalence) were E. bakuensis (ovina) (43.6%), E. ovinoidalis (23.6%), E. ahsata (15.2%), E. intricata (8.27%), E. granulosa (4.8%), E. faurei (2.8%), E. parva (1.06%) and E. pallida (0.67%).