Abstract

Repeat breeder (RB) is a cow that fails to conceive from three or more successive insemination, but with normal estrus and absence of detectable clinical abnormalities. It is one of the major problems in dairy production. In the present study, the plasma biochemistry of Sudanese crossbred RB cows was examined. Plasma glucose, total cholesterol (TC), triacylglycerol (TG), total protein (TP) and urea nitrogen were estimated with the spectrophotometer while the plasma levels of Cu, Zn, Fe, and Mn were estimated using the atomic absorption spectroscopy. The results indicate the plasma levels of glucose, Zn, Mn and Fe of RB were significantly lower (P < 0.05) than that of the normal cyclic (NC) cows. Moreover, the plasma level of urea nitrogen of RB was significantly higher (P < 0.05) than that of the NC cows. According to the obtained results, it can be concluded that correcting the plasma glucose, Zn, Mn and Fe as well as lowering the urea nitrogen may be a part of an effective strategy for treatment of repeat breeding syndrome in Sudanese crossbred cows.

Key words: Repeat breeder cows, plasma biochemistry, Sudanese crossbred cows, fertility of cows.