الفهرس | Only 14 pages are availabe for public view |
Abstract The present study was carried out at farm in Sids Beni-suef in br corporation with Animal Production Department, Faculty of br Agriculture, Fayoum University. The present study aimed to study br the effect of amelioration of heat stress on some reproductive br performance and semen characteristics in Ossimi rams by using br different methods such as Selenium, Chromium, Cold water and br water frequency. Fifteen mature Ossimi rams with an average body br weight of 75±2.3 kg and age of 2-4 years were used in this study. br Animal were equally classified into 5 groups, for treatments ( Cr, br Se, cold water, water frequency) and control group. br Thermoregulatory responses, serum metabolites (Total protein, br albumin, globulin A/G ratio, cholesterol and triglycerides), br testosterone and semen characteristics were determined as affected br by heat stress or amelioration methods. Semen samples were br weekly collected by artificial vagina br Rectal temperature and Respiration rates were decreased in treated br groups than control groups. Respiration rates were 30.8%, 26%, br 24% and 22% lower (P ≤ 0.05) in rams which received Cr, Se, CW br and WF respectively than that of control rams. Chromium- received br rams had significantly lower (P ≤ 0.05) RR (42.176 ± 0.451) than br that of other groups. Skin temperature and Pulse rate reduced by br using amelioration methods. Moreover, the use of amelioration br strategies led to enhancements and increases in Tp, Albumin, br Cholestrol, Triglycerides and glucose levels. Regarding reproductive performance semen characteristics, br testosterone levels were increased by 45.59, 41.44, 25.42 and 2.13% br as a result of treating rams with Cr, Se, WF and CW comparing with br control group. Semen ejaculate volume, sperm motility, sperm br concentration and motile either per ml or per ejaculate were br significantly alleviated by various treatments especially by Cr and br Se. Furthermore, abnormal sperms reduced as a result of treating br rams with antistress agents such as Cr, Se, CW and WF. Testis br circumference (cm) and Urethral process were elongated in treated br groups comparing to control. br Finally, treating rams during the periods of summer heat stress br enhanced most of semen characteristics and reproductive br performances. Consequently, rams may be used in breeding in case br of hot conditions by treating them with Cr piclonate and/or Se br without any unwanted effects on semen characteristics and br reproductive performances. br Key words:Rams, Heat Stress, Thermoregulation, br Metabolites, Testosterone, Semen characteristics. |