DOI: 10.36347/sjavs.2018.v05i06.008

Pages: 332-336

Abstract: The possibility of diurnal variation in semen characteristics of Red Sokoto bucks was investigated in a 60 day study. Semen was collected weekly by electroejaculation and was evaluated for colour, volume, sperm progressive motility, semen pH, viability, and morphology and spermatozoa concentration. Mean environmental temperature was found to be significantly higher in the evenings (35.52°C) than 30.07°C observed in the mornings. Best semen quality was observed in collections done in the morning than in the evening, where sperm viability was significantly higher (P<0.05) in the mornings with a difference of 4.08% from that obtained in the evening. The highest and the lowest values of, progressive motility and morphologically normal spermatozoa were observed in the mornings and evenings respectively. The percentage gross sperm motility and percentage morphologically normal spermatozoa for samples collected in the mornings were 59.88±5.84% and 97.01±1.63% respectively, which was significantly higher (P<0.05) than that obtained in the evening with 53.75±5.60% and 93.58±3.31 for percentage gross sperm motility and percentage morphologically normal spermatozoa respectively. In conclusion, diurnal variations in seminal characteristics do exist in Red Sokoto bucks raised in the sahel savannah. Highest values of percentage progressive sperm motility, viability and percentage morphologically normal spermatozoa which are indices of sperm fertilizing ability were recorded in the morning. The findings in this study therefore, necessitate the recommendation that semen intended for artificial insemination in Red Sokoto bucks are best collected in the morning.