Genetic evaluation of profitability measures in Holstein dairy cows

This study aimed to assess and estimate the genetic parameters for profit indices and identify the most reliable index for selection purposes. A total of 4 637 629 test-day records were collected from 255 804 cows across 124 herds over 15 years (2009–2024). However, the economic data were collected only from five dairy herds. Pedigree data included 575 707 animals (185 608 with records), traced using DMU Trace and structured with CFC software. Genetic parameters were estimated using single- and multiple-trait animal models with fixed effects of herd-year-season, lactation number, age at first calving, and random additive genetic effects. A DMU program was used for genetic evaluations and the best linear unbiased prediction of breeding values for the studied traits. The profitability indices include profit, income over feed cost (IOFC), income equal to feed cost (IEFC), money-corrected milk, and milk-to-feed price ratio. The results of this study revealed that profit has a moderate heritability (0.25), indicating a potential for genetic improvement. The IOFC per 100 kg of milk (IOFC milk ) had the highest genetic ( r = 0.97) and phenotypic ( r = 0.92) correlation with profit, making it the most reliable profit alternative. Furthermore, IEFC per 100 kg of milk (IEFC milk ) was genetically negatively correlated with profit (−0.80), indicating that cows with high IEFC were less economically efficient. While milk yield had improved, profitability had shown a negative genetic trend, which means that an exclusive focus on higher milk production is detrimental to long-term economic efficiency. Generally, indices such as IOFC milk and IEFC milk should be considered in breeding programs to increase profitability, efficiency, and sustainability within industrial dairy farms. This study emphasizes the importance of integrating profitability indicators into genetic evaluations. Providing novel selection criteria contributes to more efficient and sustainable breeding strategies for Holstein dairy cows.