Effects of concentrate supplementation on reproduction and lactation performance of F1-Small East African x Norwegian does

Abstract

Forty-five (12-15) months-old, grazing Small East African (SEA) x Norwegian (N) does (20.7 ± 0.6 kg BW) were used to determine effects of three dietary levels on reproductive and lactation performance for 17 months experiment in Morogoro, Tanzania. The experimental animals were randomly blocked into three dietary treatments (T200, T400 and T600 which consisted of 200, 400 and 600 g of concentrate diet respectively), with 15 does each. All does were supplied with 800 g of concentrate diet daily after kidding. The does were exposed to three bucks (>75% N-blood) for mating. Each buck was assigned to one of the treatment groups and rotated after every three days. Body weight and condition scores of the does increased (P<0.001) with the increasing levels of concentrate diet. At birth, both single and twin kids born in diet T600 (3.47 and 2.51 kg) were heavier (P<0.05) versus T400 (3.07 and 2.13 kg) and T200 (2.46 and 1.92 kg). There was no significance differences (P>0.05) among kids at weaning in all dietary treatments. Milk yield were significantly higher (P<0.001) for does fed diet T600 (1.72 L/d) versus diet T400 (1.44 L/d) and T200 (1.10 L/d) throughout the lactation. Does fed diet T600 were superior for most of the milk component analyzed compared to those fed diets T200 and T400. Based on the results obtained, it was concluded that supplementation of does during pregnancy and throughout lactation, positively improves reproductive and lactation performance of the does.