Genetic and Phenotypic Parameters for a Profit Function and Selection Method for Optimizing Profit in Dairy Cattle

作者：G. S. Gill, F.R. Allaire · 发表于：Journal of Dairy Science · 年份：1976 · DOI：10.3168/jds.s0022-0302(76)84363-9 · 被引用次数：62 · 研究领域：Agriculture Sustainability and Environmental Impact、Genetics, Aging, and Longevity in Model Organisms、Genetic and phenotypic traits in livestock

Genetic and phenotypic relationships were estimated on a profit function for 933 Holstein cows.Methods of selection among cows were investigated for profit per day of herdlife.The profit function included production, reproduction, and body weight.Heritability for profit/day during first lactation was .50-+ .12compared to .28 + .10 for milk/day in the first lactation.Correlations (genetic, phenotypic) between first lactation and lifetime records per day of herdtife were (.93, .74)for milk production and (.79, .65)for profit.Correlations between milk/day-first and profit/day-life were (.85, .55).Correlations for total lifetime production and profit were (.95, .97)and per day of herdlife were (.94, .87).Herdlife compared to lifetime traits had larger correlations with profit/day than yield/day (.64 versus .40,.69versus .48)indicating the profit function contained important factors related to herdlife besides lactation performance.Correlations between age at first calving with total lifetime production and profit were negative (-.15 to -.32, -.16 to -.07), suggesting an increase in these traits can be expected in selection for younger age at first calving.Genetic gain expected in profit/day of life from selection on profit/day-first lactation was 24% more efficient than milk/day-first.A simplified profit function may be effective for increasing profitability in dairy production by selection.