Peripheral plasma testosterone levels in two indian breeds of goats and their reciprocal crosses

Plasma testosterone levels were estimated in different male goat age groups. In Black Bengal at 15–30 days, 2–3 months, 3–5 months and in Black Bengal, Beetal, Beetal × Black Bengal and Black Bengal × Beetal at 6 months and > 12 months (n = 6 in each case). The plasma testosterone levels (mean ± s.e.m.) were high (7.1 ± 2.0 ng/ml) at 2–3 months and fell drastically to 2.6 ± 0.5 ng/ml before attaining sexually mature levels of 4.6 ± 0.9 ng/ml at 6 months and 4.1 ± 0.8 ng/ml at > 12 months. The mature bucks of all genetic groups had a plasma testosterone concentration of 4.6 ± 0.8 ng/ml. Genetic group differences were not significant.