Assessment of sperm quality of communal goats in the hard-veld region of Botswana

Abstract

The objective of this study was to assess semen characteristics of bucks kept under communal management systems in the hard-veld, southern part of Botswana. In early autumn, semen was collected from 22 bucks ranging from ≤ 2 to ≥5 years old across 20 randomly-selected communal farms using an electro-ejaculator. The buck type, age, live weight, and scrotal circumference were recorded prior to semen collection. Semen characteristics assessed were semen colour, ejaculated volume, sperm cell concentration, sperm motility, as well as morphology. The data were examined using analysis of variance with a general linear model in SAS. The common buck breed kept by communal farmers was a non-descript (mixed) breed (86%) and the Boer goat (14%) was in minority. The most predominant semen colour was creamy. The breed did not influence live weight, scrotal circumference, and semen characteristics. The younger bucks (≤2 years) had substantially lower live weight, scrotal circumference, and ejaculated semen volume than the older bucks. Semen characteristics did not differ substantially across the ages except for the sperm concentration, which was lower in bucks ≤2 years compared to ≥5 years. Live weight was strongly correlated (r = 0.81) to scrotal circumference and moderately correlated (r = 0.60) to the ejaculated semen volume. The study provides an insight into semen quality and prediction of fertility for bucks kept under a communal management system.