Some reproductive performances of Thai native (TN) and 50% TN x Anglo-Nubian crossbred does with different levels of concentrate supplementation

Abstract

A 2 x 2 x 2 factorial in completely randomized design was conducted to determine the effect of genotype of does (Thai native (TN) or 50% Anglo-Nubian (AN) crossbred), levels of concentrate supplementation(1 % body weight or ad libitum) and body condition of does (poor or good) on oestrus incidence, kidding rate and multiple birth rate of does. Does rotationally grazed on Paspalum plicatulum pasture for 4 weeks andwere supplemented with concentrate. The experiment was divided into 4 periods: 1) does run with a teaser for 105 days before mating to determine an oestrus incidence 2) does joined with bucks of the same genotypefor 45 days 3) does run with a teaser for 150 days during pregnancy and 4) does run with a teaser 90 days post-partum. Genotype, levels of concentrate supplementation and body condition of does did not significantlyaffect (P>0.05) kidding rate or multiple birth rate and average kidding rate and multiple birth rate of the does was 83.8 and 82.3%, respectively. Birth weight of kids from TN does was significantly lower (P<0.01) than that from 50% TN x AN crossbred does (1.9 and 2.5 kg, respectively). Number of days of the first oestrus incidence in post-partum period for TN does was significantly (P<0.01) less than that of 50% ANcrossbred does (59.1 days and 75.0 days, respectively). Number of days of the first oestrus incidence in postpartum for does supplemented with concentrate ad libitum was significantly (P<0.01) lower than that ofdoes supplemented with 1% BW of concentrate (60.5 and 73.6 days, respectively).

Keywords

• goats
• Anglo-Nubian crossbred
• levels of concentrate supplementation
• body conditions
• kidding rate
• multiple birth rate
• birth weight
• post-partum oestrus