The Effects of Non-Genetic Factors on Dairy Cattle Performance in East Africa Testing for Season and Parity Effects

Abstract

The season of calving has often been recognized (Cannon, 1933; Woodward, 1945, Frick. et al 1947; Carter et al 1963) as one of the main sources of variation of the lactation milk yield of dairy cattle in the temperate environment. Consequently. Evaluation of animals under the temperate conditions entails dividing the year into appropriate seasonal groups (i.e. spring, summer, autumn, winter) for the purposes of adjusting the milk records.