Selection to improve birth and weaning weight of Javanese Fat Tailed Sheep

Abstract. In Indonesia, the Javanese Fat Tailed Sheep is a very popular domestic animal for its meat production However selection to increase body weight has never been done by local farmers. As a result the variability of body weight is high, and expected that application of a selection program can improve this trait Two Steps of selection were done in order to improve birth and body weight. In the first selection, the elite group was established by selecting the best 40 females and 3 males from 12500 sheep reared by local farmers based on their mature body weight and tail length. The control group was established by randomly selecting 40 females and 4 males In the second step of selection, the best 50 % females and 5 % males of the progeny of the elite group was selected based on their weaning weight and tail size. The first selection results indicate that there was a positive genetic progress in both birth and weaning weight. Selection had increased 7.17 % and 5.48 % of male and female birth weight respectively and 9.48 % and 9.78 % of male and female weaning weight, respectively. Positive genetic progresses of birth and body weight were also found after the second selection. Birth weights of males and females were 6.75 % and 7.20 % higher than those in the control group. Male and female weaning weights were 5.60 % and 8.19 % higher than those in the control group, however, selection for weaning weight did not affect reproductive traits.