Scrotal, testicular and semen characteristics of young Dorper rams managed under intensive and extensive conditions

In this study, the influence of two feeding regimes on certain reproductive characteristics of young Dorper rams was investigated. Thirty-two Dorper rams were divided into two homogeneous groups. Rams in the first group ( n =16), 472.5±8.0 days old were fed ad libitum intensively on a diet (9.5 MJ ME/kg DM and 12.5% protein) for 7 weeks, while the second group ( n =16), 460.6±8.5-day-old rams were maintained on natural pastures and received lick supplementation (100 g/animal per day) with 16% CP, 8 MJ ME/kg DM and 10% fibre for a similar period of time. At the end of the trial period, semen was collected by electro-ejaculation from each ram and evaluated, prior to the slaughtering of the rams. Following slaughter, the scrotums were excised and dissected. Seminal, scrotal, testicular and carcass characteristics of rams from both groups were compared. Nutritional management had an influence on scrotal circumference, scrotal weight, scrotal fat, testes weight and volume. Significant greater scrotal circumference (SC) were recorded in the intensively managed (IM) rams (34.1±0.4 cm) compared to the extensively managed (EM) rams (31.8±0.6 cm) and significantly more fat deposits (particularly in the scrotal neck) were found on the IM rams (109.1±8.7 g) when compared to the EM rams (45.4±6.5 g). Significant differences between the IM (50.1±3.8% and 2.3±0.3) and EM (80.5±2.3% and 3.3±0.2) rams were observed for overall motility ( P P