Original Contribution BREED, GENDER AND SEASONAL VARIATIONS OF BLOOD PHAGOCYTIC ACTIVITY IN LOCAL SHEEP BREEDS REARED IN BULGARIA

The studies were performed in 2008 on 168 sheep and 114 rams. Investigations were carried out on 6 sheep and 6 rams from the following breeds: Karakachan, Tsigay, Replyan, Panagyurishte, Copperred Shoumen, Karnobat, Pleven Blackhead, White Maritsa and Patch-faced Maritsa, Stara Zagora and Romanov. The phagocytic activity was determined via two parameters − phagocytosis index (PI) and phagocytic number (PN). PI was determined as a ratio of phagocytized leukocytes and the total leukocyte counts, multiplied by 100. PN was calculated as the number of bacteria, phagocytized by one leukocyte. During the spring, the highest PI was found out in Replyan, Copper-red Shoumen and Stara Zagora sheep (79.33%). The lowest PI values were those of Karnobat (76.0%) and Karakachan (76.67%) sheep. Among studied rams, the highest PI was established in Tsigay and Romanov breeds – 79.33%, whereas the lowest – in Copper-red Shoumen rams – 72.67. During the summer, the highest PI was obtained in Karakachan sheep – 79.33 and Romanov sheep – 79.20, and on the contrary, Karnobat sheep had the lowest PI (р<0.05). During the autumn, Karakachan sheep had the highest PI again – 80.67, and the lowest phagocytic index (75.33) was determined for Copper-red Shoumen sheep (p<0.01). During the spring, Replyan sheep had the highest PN – 1.607, and those from the Panagyurishte breed – the lowest – 1.500 (р<0.05). The highest PN was obtained in Romanov and Stara Zagora rams' the lowest PN – in Pleven Blackhead rams (р<0.01). There was a tendency for highest PI values in sheep during the spring, a certain reduction in the summer and elevation during the autumn. For rams, PI exhibited a general increase during the summer and autumn with variable changes for the different breeds. For both sheep and rams, PN was the highest during the spring, lower in summer and thereafter elevated during the autumn.