Comparative Characteristics of the Protein Status of Romanov Breed Ewes by Season in the Kuzbass Region

Abstract

The study is devoted to the study of seasonal changes in protein metabolism in Romanov sheep in the sharply continental climate of Kuzbass. In the blood serum of healthy non-pregnant ewes aged 18.5–19 months, the total protein content was assessed by biuretic method, albumins by bromocresol, urea by urease-salicylate, creatinine by the Jaffe method without deproteination photometrically (Photometr5010v5+). The amount of globulins and the albumin/globulin ratio were calculated.  The established average values of all indicators in both seasons corresponded to generally accepted physiological standards, with the exception of globulins. The concentration of globulins was 49.12±1.71g/l in winter, exceeding the standard ranges, in summer it was within the normal range - 38.52±2.39 g/l. The levels of total protein and creatinine had no seasonal differences. The upper and lower limits with 90% confidence intervals of reference intervals for total protein were 54.00 (90% CI 49.79–58.21) – 94.00 (90% CI 89.79–98.21) g/l; for creatinine 102.00 (90% CI 94.11–109.89) – 175.00 (90% CI 167.11–182.89) mmol/ L. The values of all indicators except globulins were higher in summer (p<0.05): albumin – by 11.6%; albumin/globulin ratio – by 1.72 times; urea – by 2.42 times and amounted to 34.74±1.38 g/l, respectively; 0.96±0.067; 4.77±0.07 mmol/L. The median values of albumin in winter were 28 g/l; albumin/globulin ratio was 0.54; urea was 2.02 mmol/L.The observed seasonal differences affecting the indicators of all stages of protein metabolism suggest that they are part of a metabolic seasonal adaptation to environmental changes.