The objectives of the present study were 1) to evaluate the polymorphism of growth hormone
(GH), insulin-like growth factor 2 (IGF2) and progesterone receptor (PGR) genes in Sinai Gabali rabbits, and
2) to assess their associations with growth, litter size and milk production traits in Sinai Gabali rabbits. The
C>T, A>Del and A>G single nucleotide polymorphisms of GH, IGF2 and PGR genes were genotyped by
polymerase chain reaction-restriction fragment length polymorphism using BstUI, HpyF31 and BsaI restriction
enzymes, respectively. The C/T genotype of GH gene recorded the heaviest body weights for body weight
(BW) at 8 wk (1190.22±19.29 g) and 12 wk of age (1842.46±30.19 g) and recorded the largest litter size at
birth (LSB: 7.37±0.12 kits) traits. The Del/Del genotype of IGF2 gene showed the superiority over the other
genotypes for BW at 4 wk (507.17±8.87 g), 8 wk (1239.39±14.0 g), and 12 wk of age (1950.15±18.1 g), as
well as for daily weight gain from 4 to 8 wk (26.05±0.37 g/d), and from 8 to 12 wk of age (25.48±0.56 g/d)
traits. The G/G genotype of the PGR gene showed superiority for LSB (7.51±0.13 kits) and litter size at
weaning (6.53±0.14 kits) traits over the other genotypes. Regarding milk yield traits; the C/C, A/A and A/A
genotypes of GH, IGF2 and PGR genes yielded more milk compared to the other genotypes. The means of
total milk yield in 28 d for these genotypes were 2936±29 g, 2921±43 g and 2930±35 g, respectively. Thus,
GH, IGF2 and PGR genes might be useful for marker-assisted selection programmes for improvement of
rabbit growth, litter size and milk yield traits. |