THE PHYSICAL CHARACTERISTICS OF OVINE-CAPRINE EJACULATE MIXTURES AND THE SURVIVAL OF THEIR SPERMATOZOA IN COW'S MILK EXTENDER IN THE HUMID TROPICS.

Abstract

Semen samples were obtained twice weekly by electrical stimulation from four bucks and two rams for three months, mixed in equal volumes and evaluated for physical characteristics. Proportions of semen from each species and the ejaculate mixtures were diluted in known, volumes of skim milk and the survival of spermatozoa evaluated at 0,1,2 and 4 hours at room temperature. While the seminal characteristics of the ejaculate mixtures were good and highly comparable to those of the species, there was a progressive decline in semen motility in buck semen (59.5f2.95 to 31.89 2.37%), ram semen (57.00t3.75 to 26.25 +3.5OCl/oa)n d the mixtures (67.00f1.09 to 34.00*2.19%) from Oh to 4 h in cow's milk extender. Sperm motility in cow's milk extender was similar between the species as well as between the species and mixtures at all times of sampling except at Oh when there was a significant difference (p<0.05) between the ejaculate mixtures and ram semen, but not buck semen. These results may be indicative of the possibility of using the same media for sheep and goat semen in the tropics. The results also show that cow's milk may be a good extender for sheep and goat semen in our environment especially when fortified with energy and antibiotics.