Response of sexual activity in male goats under grazing conditions to food supplementation and artificial long day treatment

The aim of the present study was to investigate if food supplementation in photoperiodic-treated male goat increases their sexual activity during natural sexual rest period. Two groups of male goat (n=5 each) were placed separately in two herds of female goats grazed under extensive conditions in native pastures (daily from 1000 to 1800). When animals returned from grazing, males were separated from the females and placed in pens near their flock. Both male groups were submitted artificially for 2.5 mo to a long days treatment (16 h light/d) beginning on November 1. Treated group of males was supplemented daily with 1 kg of alfalfa hay (17 % CP) and 300 g of commercial feed concentrate (14 % PC) per animal. Body condition was better in the supplemented than in the control group from the middle January (2.5±0.2 vs 2.1±0.1, respectively) to the end of March (2.8±0.1 vs 2.2±0.2, respectively, P0.05). Finally, in both groups, testicular weight increased from middle December to the end of the study (from 78.0±6 to 124±4 g, in the control group and from 70.7 to 117±9 g, in the supplemented group, respectively). However, in this variable there was neither an interaction group-time, nor an effect of group (P>0.05). The results of this study show that in these conditions, feed supplementation does not increase the sexual response of male goats treated with 2.5 mo of long days under extensive grazing conditions.