GENETIC AND NON-GENETIC EFFECTS ON PRODUCTION AND REPRODUCTIVE TRAITS OF JERSEY CATTLE BREED AT WOLAITA SODO DAIRY FARM, SOUTH ETHIO

Abstract

This study was carried out to estimate genetic parameters and to evaluate non-genetic ef ects on milk production and reproductive performance of Jersey cattle via an animal model by using variance component estimation VCE-6 version 6.0.2 & PEST 4.2.5 and SAS software (2016) version 9.4 the GLM procedure. The data was obtained from a state farm, located in South Ethiopia, Woliata Sodo, Ethiopia. The least-square mean value of production traits such as Daily Milk Yield (DMY) and Lactation Length (LL) was 13.52 kg and 352.89 days, respectively. In addition, the average least-square means for reproductive traits of the Age at First Calving (AFC) and Calving Interval (CI) are 952.40 days and 490.01 days, respectively. The season has a significant (P<0.0001) ef ect only on daily milk yield (DMY). Calving year has highly significant (P<0.01) ef ects on DMY, LL, AFC, and CI, and dam parity also have significant (P<0.01) ef ects on DMY, LL, AFC, and CI. Heritability estimated were generally low on the trait studied having the value 0.19±0.02, 0.02±0.05, 0.16±0.03, and 0.18±0.04, for DMY, LL, AFC, and CI respectively. Estimated genetic correlation (rg) between daily milk yield (DMY) and lactation length (LL) were strong positive (0.88), but it takes weak negative (-0.09) for LL-AFC, and the other correlations were mild-positives. The estimated phenotypic correlation (rP) among milk production and reproductive traits were weak-positive except CI- LL (-0.01) which was weak-negative. The results of this study suggest that improvement of the performance of the pure Jersey cattle population at Woliata Sodo dairy farm is possible through improving the level of production, reproduction and data management system.