Authors : Miguel Mellado , Francisco Pastor and Jes?s Mellado
Abstract: This study examined the influence of sex ratio during multiple pregnancies on some reproductive and reproductive parameters of adult goats under intensive conditions. Goats were grouped according to sex of fetuses of the litter: females (F,FF or FFF; n= 356) and females and males (FM, FFM or FMM; n=270). Birth weight (3.11 ? 0.04 vs 2.95 ? 0.06 kg), weight at 25 days of age (7.36 ? 0.16 vs 7.27 ? 0.25 kg) and average daily gain from 1 to 25 days of age (170 ? 6 vs 174 ? 9 g) were similar between does born with a female twin and does born co-twin to a male. No effects of sex of adjacent littermate were found on pregnancy rate (0.71 vs 0.72; 1855 total services), prolificacy (1.63 ? 0.02 vs 1.66 ? 0.03) and age at first kidding (700 ? 12 vs 721 ?18). These findings indicate that the coexistence of a female with one or two males during the gestation period do not alter the growth and some reproductive performance of adult does.
Miguel Mellado , Francisco Pastor and Jes?s Mellado , 2005. Productive and Reproductive Parameters of Does as a Function of Sex of Siblings During Gestation . Journal of Animal and Veterinary Advances, 4: 427-429.