Effect of Breed and Non-genetic Factors on Body Weight and Average Daily Gains of Goats in Tunisia

Abstract

The present study was carried out to evaluate growth performance of three goat breeds in Tunisia (Alpine, Boer and Damascus) from birth to 90 days and to investigate the effect of non- genetic factors on birth weight (BW), weight at 10 days (W10), weight at 30 days (W30), weight at 70 days (W70), weight at 90 days (W90) and average daily weight gains from birth to 30 days (ADG0-30), from 10 to 30 days (ADG10-30), from 30 to 70 days (ADG30-70), from 30 to 90 days (ADG30-90), from 70 to 90 days (ADG7090). A total of 3198 goats including Alpine (n=1030), Boer (n=2084) and Damascene (n=84), born during the period 2004-2016 were used. Data analysis showed non-significant effect of breed on growth traits. However Damascus goats had the heaviest overall live weight at birth (3.99±0.05kg) followed by Alpine (3.94±0.02kg) and Boer (3.90±0.02kg) until 90 days (13.25±0.66, 12.13±0.35, 12.07±0.35kg respectively ).Average daily weight gains followed the same trend as weights. Overall, sex-type of birth, season and the combined year of birth-farm-herd influenced growth traits. Higher performances were recorded in males born as singles, during the rainy season (November to March), in 2007 and 2008, belonging to herd”1”of Chenchou experimental station and herd” 5” belonging to a private farm respectively. In conclusion, our study confirms that non-genetic factors affect these three goat breeds. Adjustments for those factors are necessary to provide standard comparisons among breeds under challenging Tunisian conditions.