ABSTRACT
The objective of this study was to determine the effect of dietary vitamin E supplementation on testicular and behavioural development, and histological appearance of testes in Karya male lambs. Thirteen lambs weaned at 2.5 months of age were used in the experiment. Experiment was carried out over a period of 70 days and all lambs were fed ad libitum on concentrate and 100 g/day clover hay per lamb. In addition, the experimental group (n=6) received a supplement of 45 mg/day vitamin E (dl-α-tocopherol acetate) per lamb. Testicular measurements and blood testosterone concentrations were recorded every second week. Behavioural tests were carried out four times per animal at three days intervals during the last 12 days of the experiment. After slaughtering, testicular tissue samples of all animals were collected and evaluated for the histological appearances. Except for mount attempts (P<0.05), sexual behaviour and testicular growth characteristics of the lambs were similar. The mounting parameters, testosterone concentrations and testes and epididymides weights were similar between the two groups. However, the mean of mounting weight was found lower (P<0.05) with Vitamin E lambs compared to control (28.78±3.48 vs. 33.98±3.64 kg, respectively). The area of seminiferous tubules was statistically different (P<0.001) between the two groups. However, there were no significant differences between the two groups for most of the reproductive characters. These findings suggest that supplementation of Vitamin E during early prepubertal age of Karya male lambs does not have considerable effects on the reproductive characteristics.