INFLUENCE OF GENETIC AND NON-GENETIC FACTORS ON THE GROWTH PERFORMANCE OFDWARF SHEEP OF DJALLONKE BREED REARED ON NATURAL PASTURE IN BENIN

Abstract

Thestudy aims to determine the variability of growth performancein Djallonkedwarf sheep reared on natural pasture in Benin according to the ecotype, sex, season, lambing rank and litter size. Data were then collected on 1061 sheep including 462 ofNorth ecotype and 599 ofSouth ecotype, from November 2014 to December 2015. These data were analyzed with SAS software (2006). The obtained results show that the sheep ecotype had affected (p<0.05) the different age-type weights and Average daily gain excluding the birth weight, weights at 270, 315, 330, 345 and 360 days. Animals of North ecotype were overall heavier than those of South ecotype. Except the birth weight, the sex had influenced the age-type weight of sheep with males heavier than females (p<0.05). The season didn’t influence age-type weights excluding the weight at 120 days. However, the average daily gains were affected (p<0.05) by season excluding the values recorded from the age of 120 to 240 days with higher ADG found in animal born during the dry season. The lambing rank had only affected the weight at 225 days, 240 days and255 days (p<0.05) with the lesser growth found in animal born at the first lambing.Except the weights recorded from the birth to the age of 120 days and the live weights at 195, 210 and 225 days, the litter size didn’t affected the others growth parameters. Non-genetic factors involved in this study must be taken into account to improve Djallonkesheep production in Benin.