Profitability, greenhouse gas emissions, and food-feed efficiency comparison of dairy-beef steers of divergent beef genetic merit in pasture-based production systems

Beef produced originating from the dairy herd forms an integral part of beef supply chains globally. The objective of this study was to quantify the economic and environmental performance of three dairy-beef genotypes differing in beef genetic merit and managed under three contrasting pasture-based feeding treatments, using a farm-level systems model and data from an animal systems experiment. The three steer genotypes modelled were: 1) high beef-merit Angus sires (HA); 2) low beef-merit Angus sires (LA); and 3) Holstein-Friesian (HF) sires. Each genotype was evaluated across one of three feed treatments: 1) control (CTL), grass-only during both grazing seasons; 2) low concentrate (LC), supplemented with concentrate during the first grazing season, pasture only during the second grazing season; and 3) high concentrate (HC) supplemented with concentrate during the first and second grazing season; amounting to nine scenarios. High Angus steers were most profitable (€424/animal, €1,362/ha), followed by LA (€337, €1,126) and HF (€188, €659). There were no interactions between genotype and feed treatment, with the CTL treatment having highest profit per head due to lower concentrate input costs. High Angus had the lowest greenhouse gas emissions between genotypes, and concentrate use reduced emissions per kg of beef, but CTL had the lowest total emissions per ha and per farm due to greater forage use. In conclusion, this study demonstrates the financial and environmental benefits of high beef genetic merit sires in dairy herd for dairy-beef systems and producers.