PENDUGAAN PARAMETER GENETIK PERFORMA PRASAPIH DOMBA GARUT DI UPTD-BPPTDK MARGAWATI GARUT

Pengembangan sumber daya genetik ternak lokal penting dilakukan untuk memenuhi permintaan dagingdomba yang tinggi di Indonesia khususnya Jawa Barat melalui kegiatan seleksi bibit unggul Domba garut.Penelitian ini bertujuan untuk mengetahui nilai parameter genetik sifat-sifat prasapih Domba garut. Sifat-sifat yang dianalisis pada penelitian ini yaitu bobot lahir (B0), bobot 30, 60, 90 hari (B30, B60, B90), dan bobot sapih pada 100 hari (B100) Domba garut di UPTD-BPPTDK Margawati Garut yang berasal dari 104 ekor pejantan, 1.809 ekor induk, 2.921 ekor anak domba jantan, dan 2.632 ekor anak domba betina. Total catatan yang dianalisis yaitu 27.019 catatan bobot badan yang terdiri atas 6.559 catatan B0, 5.702 catatan B30, 5.248 catatan B60, 4.843 catatan B90 hari, dan 4.667 catatan B100 Tahun 2012-2019. Analisis data menggunakan Restricted Maximum Likelihood (REML) untuk menduga heritabilitas dengan software Variance Components Estimation (VCE) 6.0, menggunakan model maternal genetic effect (m2) dan lingkungan bersama (c2). Efek tetap yang dimasukkan ke dalam analisis yaitu jenis kelamin dan tipe kelahiran. Hasil penelitian menunjukkan bahwa nilai heritabilitas B0, B30, B60, B90, dan B100 menggunakan model maternal genetic effect dan lingkungan bersama yaitu sebesar 0,133±0,04, 0,108±0,03, 0,099±0,03, 0,122±0,03, 0,123±0,03, artinya nilai-nilai heritabilitas tersebut masuk dalam kategori rendah. Nilai maternal genetic effect dan lingkungan bersama B0, B30, B60, B90, dan B100 Domba garut 0,095±0,03, 0,163±0,03, 0,137±0,03, 0,113± 0,02, 0,115±0,02 dan 0,455±0,16, 0,268±0,13, 0,274±0,13 0,269±0,13 0,278±0,12. Hal ini menunjukkan bahwa pendugaan parameter genetik lebih akurat jika melibatkan maternal genetic effect dan lingkungan bersama.

Evaluation genetic parameters for weight at different ages in Baluchi breed of sheep

Improving breeding values and breeding programs should be done based on genetic potential. The range of additive direct heritability and maternal environment heritability for birth weight is about 0.07 to 0.22 and 0.1 to 0.33 respectively the range of these values for the following weights are 0.09- 0.58 and 0.01- 0.17. the objective of this study was to predict the direct additive genetic effect, maternal genetic effect and heritabilities of lamb weight traits in baluchi breed of sheep.

Genetic parameters of weights, ultrasonic muscle and fat depths, maternal effects and reproductive traits in Welsh Mountain sheep

Genetic parameters of weight traits, ultrasonic fat and muscle depths, maternal effects and reproductive traits of Welsh Mountain sheep were estimated based on analyses of data from the nucleus flock of a cooperative breeding scheme. The traits analysed were 12 week weight (TW, no. = 11201), mature weight (MW, no. = 2376), weight at scanning (SW, no. = 1022), muscle depth (SM, no. = 1024), fat depth (SF, no. = 1024), litter weaning weight (LW, no. = 3445) and litter size (LS, no. = 3445). (Co)variance components were estimated in univariate and bivariate animal models. Heritability estimates from univariate analyses were 0.16, 0·49, 0·29, 0·24, 0·22, 0·20 and 0.15 for TW, MW, SW, SF, SM, LW and LS respectively. Genetic correlations among the weight traits were high. There was no detectable correlation between SF and SM. SF and SM were strongly correlated with SW but not with the other weight traits. LW was strongly correlated with MW and SW but not with TW, although the latter analysis was inconclusive. Maternal heritability was similar (0·11) for the univariate analysis of TW and all bivariate analyses involving TW (except for TW v. LW). The permanent environmental effect of dam was generally low (0.02 to 0.04) whilst litter effects were generally high (0·20 to 0·23). The correlation between direct and maternal genetic effects for TW were generally small and non-significant. The maternal genetic effect for TW was moderately correlated with the direct additive effect for MW and SW but was not significantly correlated with the direct additive effect for LS, SM or SF. A very large positive correlation was found between the maternal genetic effect for TW and the direct additive effect for LW. The implications of the results are discussed in the context of selection indices for Welsh Mountain sheep.