Relatórios de transplante: acesso aberto

Abstrato

Effect of Season, Parity, Exotic Gene Level and Lactation Stage on Milk Yield and Composition of Holstein Friesian Crosses in Central Highlands of Ethiopia

Dereje Shibru

The study used twelve years recorded data’s analysis for milk yield and composition of Holstein Friesian crossbreddairy cows in Holleta agricultural research center dairy farm.Data were summarized and categorized into the season, genotype (exotic blood level), Parity and lactation stages.The summarized data’s were season (219 wet, 1055 dry),genotype (1,117 for 50%, 115 for 62.5% and 42 for >75%),Parity (474 for parity-2, 356 parity-3, 270 for parity-4 and 174 for parity-5), Lactation stage (483 for early, 445 for midand 346 for late). Analysis of means and standard errors of the mean for the parameter studied was estimated using SAS. The General Linear Model was used for analyses of variance on average monthly milk yield and composition