Seasonal content and variability of erythrocyte parameters of Romanov sheep in the conditions of Kuzbass

The content of erythrocyte parameters in the peripheral blood of Romanov sheep sheep was studied according to the seasons of the year. The experiment included purebred non-pregnant sheep aged 18 months with a live weight from 46 to 56 kg, zoned in Kuzbass. The studies were conducted before the start of the sexual season in July and after its end in February. Blood was taken from the jugular vein by vacuum method into tubes with K2EDTA. Blood parameters were measured using a PCE90 Vet hematology analyzer. For comparative statistical analysis, taking into account the nature of the data distribution, the Student's criteria for independent samples and Mann-Whitney were applied. The content of the total number of red blood cells in the summer season, hemoglobin, hematocrit, average erythrocyte volume, average hemoglobin content in erythrocytes, average hemoglobin concentration in erythrocytes (MCNS), and the width of red blood cell distribution (RDW) in both seasons varied within generally accepted normal values. The number of red blood cells in winter was below normal. Erythrocyte counts were characterized by a wide range of phenotypic variability. Seasonal differences have been established for all indicators except the average hemoglobin concentration in red blood cells. The number of red blood cells in the summer season was 1.8 times higher than in winter (p<0,05). and were 3.99±0.05 ×1012/l and 7.4×1012/l. The levels of hemoglobin, hematocrit, average volume of red blood cells, MSNS, RDW were higher in winter by 13.5%, 13.3%, 51.2%, 48.1% and 12.9%, respectively (p<0,05). The variation of erythrocyte parameters between seasons can serve as indicators of the environmental impact on animal health.