Effect of Dietary Energy Supplementation on Feed Intake, Growth and Reproductive Performance of Goats under Grazing Condition

Abstract

Twelve female goats were used in a 90 day trial to study the effects of dietary energy supplementation to grazing on feed intake, growth and reproductive performance of female goats. Animals were blocked according to live weight and blocked groups were assigned at random into three feeding regimes i.e. low, medium and high energy (10.02, 11.06 and 11.98 MJ ME/kg DM). Each goat received 250 grams of supplemental diet in addition to grazing. Results showed that, daily average dry matter and crude protein intake significantly (P<0.05) decreased from 406.1 to 362.4 g/d and 47.7 to 40.4 g/d when supplemental energy level increased from 10.02 to 11.98 MJ ME/kg DM. Energy supplementation had positive effect on energy intake. ME intake significantly (P<0.05) increased from 3.75 to 4.25 MJ/d as well as the digestibility of OM and CF significantly (P<0.05) increased from 62.25 to 73.68% and 43.80 to 53.21% respectively as the level of supplemental energy increased from 10.02 to 11.98 MJ ME/kg DM. However, the digestibility of DM, CP, NFE and EE was similar (P>0.05) irrespective of level of energy supplementation. Average daily live weight gain increased (P>0.05) in a linear fashion and the mean values were 37.7, 44.4 and 52.9 g/d for low, medium and high energy supplemented diets respectively. Birth weight of kids was highest i.e. 0.75 kg fed high energy diet and lowest i.e. 0.55 kg fed low energy diet. These results indicate that, increasing levels of supplemental energy improved live weight gain and reproductive performance of female goats. Therefore, supplementation of higher level of dietary energy (11.98 MJ ME/kg DM) may be suggested for optimizing growth and reproductive performance of female goats under grazing condition.