Vol. 11, Special Issue 10 (2022)

Author(s):
Altaf Ahmad Reshi, Hidayatullah Tak, KH Bulbul and ZA Wani

Abstract:
The study was carried in two cattle calves of age around one year with the aim to study the changes in the morphology of Eimeria oocysts with time and under different pooling conditions. One calf was highly infected with Eimeria alabamensis and Eimeria bovis with an oocyst per gram (opg) count of about 30000 and other was highly infected with Eimeria zuernii with an opg count of about 24000. However a very lesser percentage (5-10 percent) of other Eimeria species (E. auburnensis, E. ellipsoidalis, E. cylindrica, E. subspherica) was also present in both the cases. Different pooling procedures were applied for DNA extraction. Some portion of pooled and intact faecal samples from both the calves were kept preserved in a refrigerator for about two months. On examination after pooling under different protocols, a decrease in the oocyst count of E. alabamensis and E. bovis in sample first and also some unique changes in the morphology of some oocysts along with a small black rounded and vibrating cylindrical mass was observed. However, no decrease in opg count or any distinct changes were noticed in the oocysts of E. zuernii in sample second under same conditions. A change was also observed in some oocysts in preserved samples. The identity of E. alabamensis, E. bovis and E. zuernii was ascertained at morphological level and confirmed by molecular sequencing while the rest of species were identified only on morphological basis.