کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5795279 | 1554348 | 2016 | 6 صفحه PDF | دانلود رایگان |
- Estimate goat production potential through simulating flock population growth.
- Calculation of Ne and ÎF in Xhosa lob eared goats.
- There were high inbreeding levels in the flocks surpassing the optimal threshold.
- The need to conserve the endangered Xhosa lob eared goats.
This study was conducted to determinelevels of inbreeding depression of indigenous Xhosa lop eared goats and their impact on reproduction. Data was obtained through a monitoring study on 100 households with average flock sizes of52 (Bushveld) and 25 (Grassveld) in the Eastern Cape Province of South Africa. The DynaMod model was used to simulate future trends of both current and improved goat production scenarios. Goat class distribution was characterised by few bucks and high doe proportions across all the villages. Breeding ratio (0.1) was above the recommended 0.04 in both areas despite lack of buck ownership in most households. Generally, the goats in both areas had a low reproductive performance. There was low kid survivability of multiple births as higher prolificacyin the Grassveld flockscoincided with increased kid mortality. The improved production simulation of the Grassveld indictated a possibility of genetic unfitness in its flocks. This was validated by high increase in ÎFexceeding the acceptable threshold of 0.063. The Newas below 50 in both areas hence this indicated an endangerment to the existence of indigenous Xhosa lopeared goats. The negative relationship between Ne and fecundity showed that inbreeding depression was reducing flock fertility. The study concluded there were high levels of inbreeding in Xhosa lop eared goats which resulted in low reproductive performance and increased kid mortality.
Journal: Small Ruminant Research - Volume 144, November 2016, Pages 164-169