Reproduction characteristics of ouled djellal rams in a semi-arid area in algeria

Abstract

The assessment of reproduction characteristics of an Algerian local sheep in a semi-arid zone was the objective of this study. Twenty rams of Ouled Djellal breed were used. The parameters analyzed were testosterone rate, testicular diameter, ejaculate volume, sperm concentration, mass motility, and percentage of live and dead spermatozoids (SPZ). The results obtained showed that the mean monthly testosterone rate was high throughout the year (4 ng/mL), increased in spring, peaked in summer (July) (4.9 ng/mL), and decreased in autumn and winter to reach a minimum value (January) of 1.9 ng/mL. Similarly, testicular diameter, ejaculate volume, sperm concentration and count showed high levels in spring and summer and decreased in autumn and winter. The maximum and minimum values were respectively, 7.09 cm, 1.55 mL, 4 billion/mL, 3.5, 79.37%, 21% and 5.46 cm, 0.80 mL, 2.50 billion SPZ/mL, 2.81, 77.36%, and 20.42%. Significant effects of season on serum testosterone levels, testicular conformation, ejaculate volume, and concentration were recorded in this study. Indeed, the rates of these parameters increased significantly (P<0.05) during spring/summer and decreased during autumn/winter except for motility, and the percentage of live and dead sperm. Testicular conformation was positively correlated with testosterone concentration, ejaculate volume, and semen concentration. To conclude, Ouled Djellal breed seemed not to be very sensitive to the photoperiod and little affected by high temperature.

Keywords

• sperm
• ram
• photoperiod
• local breed
• temperature
• season