Genetic and phenotypic analysis for profitability in Iranian Holsteins

Abstract

The objectives of this study were to assess profit and to document phenotypic and genetic trends for profit in Holstein dairy cows of Iran. A total number of 219 507 first lactation cows with performance records from 569 herds were used to calculate profit per cow per year. Economic data sources used for calculations were from three large dairy farms representing the marketing circumstances of Iran during the 12 yr study period (2000–2011). Variance components were estimated using the average information restricted maximum-likelihood procedure based on an animal model. An average cow of the population had its first calving at 25.4 mo of age, produced 7616.9 kg of milk in its first lactation, and generated a net profit of $1096.20 US per year. Profit calculated as a phenotype for each individual cow had a moderate heritability of 0.22, but our data did not support profit as an alternative to selection based on an economic selection index. The phenotypic and genetic trends for profit were −$44.43 US and $5....