The relationship between some blood elements and metabolites with repeat breeding in dairy cows at Azarnegin dairy farm

This study was carried out to evaluate effect of some blood elements and metabolites on repeated breeding in dairy cows. Blood samples (n=62) were taken from both healthy and repeated breeding cows. Then، the concentrations of glucose، urea، total protein، calcium، phosphorus، cholesterol and triglyceride were measured with spectrophotometer and of insulin and progesterone hormones with ELISA. Two statistical models were used in this study: in the first model، using GLM procedure، the effects of status، parity، breeding season and milk records in sampling month (as covariate) on measured blood metabolites and hormones. The results indicated that breeding status of animal had significant effect (P<0. 01) on blood phosphorus and insulin and breeding season had highly significant effect (P<0. 01) on blood''s phosphorus، total protein and insulin while had significant effect (P<0. 05) on calcium and progesterone. Parity had significant effect (P<0. 05) on blood''s urea only. Milk records in sampling month had no any significant effects on any of the metabolites and hormones. In the second model، the logistic regression was used to find any relationship between animal''s status with measured variables. The results showed that blood insulin concentration had significant effect (P<0. 01) only. It can be conclude that with one unit increase in insulin concentration، probability ratio of healthy to diseased animals increased by 4. 1021 units.