Estimation of genetic parameters for litter traits in Gabali rabbits raised in the north-western coast of Egypt using multi-trait animal model [electronic resource].

Includes references.

The experimental work of this study was carried out at Maryout experimental station, Desert Research Centre, Ministry of Agriculture and Land Reclamation, Egypt. Data of 428 litters from 145 does fathered by 20 sires and mothered by 61 dams were collected on Gabali rabbits during the period from 2003 to 2007. Genetic parameters estimated for litter traits (litter size at birth, LSB, 21 days, LS21, and at weaning at 28 day, LSW, litter weight at birth, LWB, 21 days, LW21 and at litter weight at weaning at 28 days, LWW). Multi-trait animal model was used to estimate heritability, repeatability, and permanent environmental effect as well as to estimate genetic (rg), permanent environmental (rpe), environmental (re) and phenotypic (rp) correlations between the studied traits. Actual means of Gabali rabbits were 5.74, 3.75 and 3.51 young for LSB, LS21 and LSW, respectively, while, they were 318, 1205 and 1655 g for LWB, LW21 and LWW, respectively. Litter traits in Gabali rabbits tended to be lowly, moderately or highly heritable and repeatable. Heritability (or repeatability) estimates for LSB, LS21 and LSW were 0.30 (0.70), 0.41 (0.41) and 0.18 (0.19), respectively, while, for LWB, LW21 and LWW were 0.34 (0.80), 0.00 (0.00) and 0.22 (0.22), respectively. Proportion of permanent environmental variance for doe performance was low for most traits, except for LSB and LWB. Estimates of rg were positive between all the correlated traits and high in values (0.98, 1.0 and 0.97) between LSB and LWB, LS21 and LW21 and LSW and LWW, respectively. Estimates of rpe between LSB and each of LWB, LSW and LWW were 0.99, -0.69 and 0.32, respectively. Estimates of re were 0.88 and 0.90 between LSB and LSW and between LS21 and LW21, respectively. Estimates of rp, between litter traits were positive and moderately high in magnitude, except between LSB and LWW, LWB and LSW.

Summary in Arabic.

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