VARIABILITY OF THE NUMBER OF ERYTHROCYTES IN SHEEP BLOOD. II. GENERAL EVALUATION OF THE INTERACTION OF BREED AND SEASONAL DIFFERENTIATION

Krasimir Boychev, Katya Tsenova, Zapryanka Schindarska

Abstract: The effect of breed and seasonal differentiation of the number of erythrocytes in sheep blood within the range of the alternative source of variation was analyzed. The role of the interaction of both factors in the structure of total variability of the hematological parameter discussed was evaluated. Three hundred and ninety four animals of four breeds (Avassi, East Friesian, Pleven black-headed, Romanov) and Synthetic Population Bulgarian Dairy sheep were included in the experiment. The blood samples were taken in April, July, November and February. The number of erythrocytes was determined by optical camera method. A very important effect of the breed appurtenance (50.10%) was registered in autumn. Greatest seasonal variability of the number of erythrocytes was found for East Friesian breed. The basic part of the total factor's effect for the two evaluated sources of variation of the hematological parameter discussed was associated with seasonal changeability, while the effect of interaction of both factors was significant, but considerably less important.

Keywords: breeds; erythrocytes; interaction of both factors; seasons; sheep; sources of variation

Date published: 2023-03-01