Impact of genetic and environmental factors on birth weight of Fulbe sheep in Cameroon

Abstract

From 1984 to 1990, data were collected on birth weights of 607 progeny from 266 dams, originating from a random bred non-selected foundation population of Fulbe sheep kept at the Animal and veterinary Research Station, Garoua (IRZV). The results from the analyses showed that the average age at first lambing was 15 months and the majority of the ewes (57.69 %, n = 225) lambed once. Conceptions peaked at the beginning and at the end of the rainy season. The mean lambing interval decreased with increase in parity and ranged from 10.8 to 13.3 months. Sex of the animals and sex by type of birth interaction did not affect birth weights (p > 0.01). On the other hand, the random effect of dam and the fixed effects of year of birth, month by year interaction, type of birth and parity (p < 0.001) were higher than the effect of month of birth (p < 0.01). Heritability estimates from lambing interval regression of the offspring on that of the dam, the birth weight of the lamb on that of the ewe and from dam variante component were 0.07, 0.35 and 0.45, respectively.