Effect of copper and zinc supplementation on growth, blood serum copper and zinc levels, scrotal circumference and semen quality in growing male boer x nubian bucks

Abstract

The aim of the present study was to evaluate the effect of Cu and Zn supplementation on growth, blood serum Cu and Zn levels, scrotal circumference and semen quality in growing male Boer x Nubian bucks. Twenty eight male goats were fed twice daily at 07:00 and 19:00 h with a total mixed ration (TMR) containing 10.3 and 22.5 mg/kg DM of Cu and Zn, respectively. TMR was supplemented with four treatments being: control, Cu (21.7), Zn (5.6), and Cu-Zn (21.7 and 5.6, respectively) which was provided as a mineral premix. Live weight and Cu and Zn levels were analyzed under a completely randomized design with repeated measures. Scrotal circumference and semen quality were analyzed by analysis of variance using the general linear model. The comparison of differences between treatments was done using Tukey test. There were no differences in live weight, scrotal circumference, ejaculate volume and sperm concentration. Blood serum concentration of Cu increased (p < 0.0001) with Cu treatment. Blood serum concentration of Zn increased (p < 0.05) with Zn supplementation. The motility and viability of sperm in the ejaculate were affected by Cu and Zn supplementation treatments. Based on the above, in bucks fed with a TMR supplemented with Cu and Zn increase blood serum Cu and Zn levels and improved the percentage of sperm motility and viability from the ejaculate.