الفهرس | Only 14 pages are availabe for public view |
Abstract The present study was carried out in the Rabbit Production Farm, Agricultural Researches and Experiments Station, Faculty of Agriculture, Mansoura University, Mansoura , Egypt, during the period from July to December 2005. The main objective was to reduce deleterious effects of heat stress on rabbits productive and reproductive performance during summer and autumn by injection different doses of vitamin AD3E. Rabbits which were used in the present study were fifty NZW does and fifteen bucks. Both does and bucks were divided into five groups (10 does and 3 bucks in each group). The first group was control that injected with 1.00 ml from saline solution (0.9 ml Na Cl), the second, third , fourth and fifth groups were biweekly injected with doses 0.5, 1.00, 1.50 and 2.00 ml /doe from vitamins AD3E, respectively. Data were collected for tow seasons and included number of services per conception, days open, gestation period length and kindling interval. The productive traits include litter size, litter weight, mortality rate, mean bunny weight, daily weight gain at birth, 21 days and at weaning. Semen characteristics for experimental bucks were also examined . Ejaculate volume, mass motility (score), progressive motility%, sperm cell concentration, dead spermatozoa%, abnormal spermatozoa%, sperm output, motile sperm / ejaculate and live sperm /ejaculate were determine. In conclusion, injection different levels from vitamin AD3E at levels of 0.5, 1.0, 1.5 and 2.0 ml/animal biweekly to rabbits (does and bucks) improved conception rate (decrease number of services per conception) and improved both mean bunny weight and daily weight gain as well as viability of produced bunnies during autumn and summer. Also, injection of vitamin AD3E improved productive and reproductive performance and semen quality. The level of 1.00 ml/animal showed the best results for does and bucks. Therefore, heat- stressed buck rabbits injected with 1.00 ml from vitamin AD3E could be used to improve reproductive efficiency as a therapy for temporary summer sterility which commonly occurs for some bucks and does during exposure to hot climatic conditions. |