Abstract

Background and Aim: This study was conducted to determine the effect of seasonal variations on testosterone serum concentration, body weight, scrotal circumference, and some sperm parameters in rams living in a semi-arid region of eastern part of Algeria.

Materials and Methods: Blood samples were taken monthly from eight Ouled Djellal rams, aged between 3 and 4 years, in the Technical Institute of Breeding "ITELV" located at Ain M'lila City. Sperm were collected by an electro-ejaculator once a month for 1 year (spring, summer, autumn, and winter: 3 times/season).

Results: Mean values of volume, mass motility, live sperm, and scrotal circumference were higher during spring (p<0.05) with 1.23±0.26 mL, 3.39±1.07, 79.16±15.82%, and 36.29±1.91 cm, respectively; whereas, the sperm concentration was higher during autumn with 1.19±0.56x109 spz/ml compared to 0.46±0.13x109 spz/mL to spring. The season influenced significantly the percentage of abnormal sperm (p<0.05), especially during winter (6.47±2.12%), but had no influence on the weight of rams. Seasonal hormonal activity was high with 4.89±2.06 ng/mL and 3.09±1.35 ng/mL of testosterone in mating seasons (spring and autumn, respectively), knowing that the sexual season is not marked too much in these latitude.

Conclusion: We can conclude that testosterone concentration is strongly correlated with the scrotal circumference and that the season has a significant influence on spermatic parameters, and that despite the large variations in sperm production, the rams can be used throughout the year. Keywords: scrotal circumference, season, semi-arid area, spermatozoon, testosterone, weight.

Keywords: scrotal circumference, season, semi-arid area, spermatozoon, testosterone, weight.