Effects of non-genetic factors on the birth weight, litter size and pre-weaning survivability of West African Dwarf goats in the Accra Plains

2014

English

A total of 675 records each on birth weight, birth type and pre-weaning survivability of West African Dwarf (WAD) goats kept on natural pasture over a period of 9 years were assessed to determine the effects of environmental factors on them. The overall mean birth weight was 1.20±0.01 kg. Birth type, season of birth, sex, parity and year of birth all had significant effect on birth weight of kids. Single born kids (1.28±0.02 kg) were heavier than twins (1.21±0.01 kg) and triplets (1.13±0.02 kg). Kids born in the major wet season (1.25±0.02 kg) were heavier than those born in the dry and minor wet seasons. Male kids (1.25±0.01 kg) were heavier than their female counterparts (1.15±0.01 kg). Parity 6 kids recorded the highest birth weight (1.25±0.03 kg) which was higher than those of parities 2 and 4 but not 1, 3 and 5. Mean litter size for does was 2.07±0.03. Litter size in the major wet season (1.96±0.05) was lower than those of the dry (2.09±0.04) and minor wet (2.13±0.06) seasons. Litter size of parity 1 kids (1.52±0.05) was lower than those of subsequent parities. Litter size of year 2003 kids (1.33±0.21) was lower than those of subsequent years. The overall mean pre-weaning survivability was 79.9%. Birth type, parity of does and year of birth affected pre-weaning survivability whilst season of birth and sex had no effect. Environmental factors have substantial influence on birth weight, litter size and pre-weaning survivability of WAD goats.

Nyameasem, J. K.; Hagan, B. A.; Asafu-Adjaye, A.; Duncan, J. L.