Seasonal influence on sperm parameters, scrotal measurements, and serum testosterone in Ouled Djellal breed rams in Algeria

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

Improved stability criteria for sampled-data systems with input saturations

International audienceIn this chapter, the design of either the controller or the network is ad- dressed for sampled-data systems with input saturation. Using modified sector conditions, an adequate looped functional, and the Wirtinger-based integral inequality, quasi-LMI conditions, with a scalar parameter to tune, are proposed in the regional (or local) context for both design problems. The associated convex optimizations are briefly described. Finally some examples show the efficiency of the methods with respect to existing results