Estimation of variance and genetic parameters for pre-weaning weights of individualLandrace X Desisynthetic piglets

Abstract

Variances and genetic parameters were estimated for birth weight (BW), 14 day body weight (14dW), 28 day body weight (28dW), 42 day body weight (42dW) and weaning weight or 56 day body weight (56dW) in the Landrace X Desi synthetic piglet population reared under sub-temperate agro climatic region of India. The data were analyzed using restricted maximum likelihood (REML) fitting six animal models with various combinations of direct and maternal effects. Estimates of genetic and permanent environmental correlations were obtained using bivariate analysis of an animal model and computed with the DFREML program. A log likelihood ratio test was used to select the most appropriate univariate model for each trait. The direct estimates of heritability were 0.43 ± 0.04, 0.31 ± 0.04, 0.35 ± 0.05, 0.40 ± 0.06, and 0.49 ± 0.06 for BW, 14dW, 28dW, 42dW, and 56dW, respectively and it increased with age from 14dW to 56dW. The permanent litter effect progressively decreased and was minimum at 56dW, ranged from 0.21 ± 0.06 to 0.34 ± 0.04. Further, maternal genetic heritability was the highest, ranging from 0.16 ± 0.07 (model 5) to 0.18 (model 6), at age of weaning and the lowest for BW, from 0.04 ± 0.03 (model 5) to 0.06 (model 6). The presence of permanent litter effect was more important since it increased the accuracy of last three models (models 4-6) significantly over the first three models (models 1-3) without permanent litter effect. The selection of 56dW would be more reliable for genetic progress rather than the selection of BW. The direct additive genetic correlation (r a ) between BW and 56dW was −0.158 ± 0.29 which revealed that higher BW may not result for favorable changes in weaning weights which was in contradiction to many earlier reports.

Genetic parameter estimates for growth performance of crossbred piglets

“…The variation in heritability estimates reported in literature may be due to differences in breeds, management and the models used in analysis. For litter environmental effects (c 2 ) at birth, the literature estimates ranged from 0.02-0.34 (Kaufmann et al 2000, Solanes et al 2004, Chimonyo et al 2006, Mondal et al 2014. Our estimate of 0.16 was in close agreement with Canario et al (2010) who reported c 2 as 0.15.…”

“…Weekly body weights of male and female piglets from birth to weaning are important for subsequent selection (Banik et al 2013). Unbiased estimation of such parameters is complicated by the presence of maternal genetic and permanent litter effects (Mondal et al 2014). Presumably due to the labour costs involved in recording such traits and insufficient pedigree information, there is a paucity of studies about the weekly growth performance of individual piglets accounting for the influence of direct additive, maternal genetic and litter environmental effects simultaneously.…”

“…Post-weaning weights at weeks 12 (W12) and 32 (W32) were also analyzed during investigation. The breeding and management policy and the climatic conditions at the farm have been described in detail by Mondal et al (2014).…”

Identifikasi Sifat-Sifat Produksi Persilangan Babi Duroc ean Yokshire

“…Hal penting mengenai parameter produksi pada ternak babi yang dipengaruhi oleh persilangan antar bangsa babi menurut Pardosi (2004) diantaranya jumlah anak babi yang dilahirkan per induk perkelahiran, berat lahir, jumlah anak lepas sapih, dan berat sapih. Persilangan akan meningkatkan produktivitas pada babi Yorkshire sesuai laporan Paura et al (2014) and Mondal et al (2014). Berdasarkan uraian tersebut diatas, maka dilakukan penelitian untuk mengetahui pengaruh bangsa babi terhadap litter size, berat lahir, berat sapih dan mortalitas anak babi prasapih pada babi Yorkshire, dan Duroc serta persilangannya.…”

Pendugaan Pola Genetik dan Fenotipik Sifat Reproduksi Ternak Babi di Provinsi Bali

“…Hasil ini berbeda dengan laporan Kasprzyk et al (2007) yang melaporkan pola yang meningkat untuk sifat litter size dan jumlah anak yang disapih. Perbedaan antara model dan metode perhitungan dan juga efek dari lingkungan dan faktor bangsa dapat memengaruhi pola genetik (Mondal et al 2014;Tomiyama et al 2011). Kecenderungan pola genetik yang konstan pada mortalitas prasapih antara 2010-2016 kemungkinan disebabkan oleh perilaku induk babi dalam mengasuh anak babi tersebut yang relatif sama setiap tahun.…”