Reproductive and body size measurements in a cohort of Roan- and Sable antelope (Hippotragus equinus- and niger) in South Africa

Abstract

The objectives of this study were to provide veterinarians and game breeders with objective body measurements and measurements of the male reproductive system that can act as a guideline for the preforming breeding soundness evaluation’s (BSE’s) in Roan- (Hippotragus equinus) and Sable antelope (Hippotragus niger) that are kept in captivity in South Africa. The later objective was to establish if there are any significant correlations existing between body measurements known to have economic value to the farmer, and measurements that may potentially influence the breeding ability of male Roan- (Hippotragus equinus) and Sable antelope (Hippotragus niger). Captive bred antelope, in Kimberley, Northern Cape area of South Africa were used to collect data from Roan and Sable bulls were darted during the summer (January) and winter (June) periods of 2018, during which each bull’s body measurements (weight, age, body length, length of front leg, horn length, horn rings, horn length tip-tip, horn base circumference) were taken, standard measurements for breeding soundness (scrotal circumference, prostate length and width, testis size, - shape and elasticity) were measured and semen samples were collected for macroscopic (colour, volume, pH, marbling) and microscopic (mass motility, concentration and sperm morphology) evaluation. Body measurements that are potentially associated with economic value such as horn length were, in this study, not correlated with any male reproductive measurements that are potentially associated with the breeding ability of Roan- and Sable antelope kept in captivity. The study also indicated, no strong correlations between physical and reproductive traits that could be confirmed. A weak positive correlation was found between body weight and SC, length of the front leg and SC, mean horn length and length of the front leg and semen concentration and the scrotal circumference. There was no correlation between semen volume and SC in Roan bulls. The Sable bulls showed a correlation between semen volume and SC but it was not significant. However there were increases in SC, semen volume and concentration noted in one bull that was moved to a breeding camp with females after his initial semen collection.