Utjecaj sezone parenja i stanja tijela na zootehničke parametre ouled djellal ovaca u polupustinjskim područjima

Abstract

In this study, a database was created by monitoring 3000 Ouled Djellal ewes, belonging to ten breeding farms and representing two modes of reproduction management. The data collected make it possible to measure the reproductive performance of females and to determine the influence of non-genetic factors on different parameters. The Body Condition Score (BCS) was calculated to compare performance in relation with breeding conditions. The results showed that fertility and prolificacy accounted for 91.1±0.1% and 116.4±0.2% in the reproduction mode respectively based on one lambing/year with exclusive spring control, and of 53.5±0.2% and 101.2±0.1% respectively in the traditional lambing system spread overthe year (with the ram permanently present in the flock) (P<0.05). The BCS varied according to mating season and feeding system. Indeed, as the BCS at mating increased, fertility, prolificacy and productivity improved. Ewes whose BCS at mating was equal to or greater than 3 obtained the best performance, while those with a lower BCS were less fertile, less prolific, and less productive. The average productivity of Ouled Djellal sheep was 107.0±0.1%, and 54.8±0.3%, respectively, in the first and second mode of reproduction management (P<0.05). This study highlights the main sources of variations and their interactions.