Effect of Contrasting Tropical Grazing System Intensification on the Performance of Holstein and Jersey‐Holstein Crossbred (Kiwi Cross) Dairy Cows

Milk production in Brazil relies on pasture, and intensifying production systems help reduce land use, leading to reduced deforestation and environmental impact. The hypothesis that Jersey crossbred cattle are particularly well suited to grazing systems is also important for Brazilian livestock sustainability. Research with environmental, economic and social impacts is required to confirm this and animal performance—the focus of this study—influences all these aspects. Twenty‐four Holstein and 24 Jersey‐Holstein crossbred dairy cows were used to evaluate the effect of different pasture management systems on milk production and composition. Treatments (2 × 2 factorial arrangement) included two cattle genotypes (Holstein and Jersey‐Holstein) and two pasture management systems (extensive with low stocking rate, CLS and intensively managed and irrigated with high stocking rate, RHS), evaluated over four agricultural seasons in two consecutive years. The RHS system increased milk yield per area by 258% relative to the CLS system, resulting in similar increases per area in fat‐corrected milk, fat, protein, lactose, total solids and dry defatted extract production. The increase in stocking rate, driven by higher spring and summer forage production, led to higher productivity despite lower individual milk production. Jersey‐Holstein cows produced milk with higher crude protein content (3.3%) compared to the Holstein cows (3.2%). No treatment effect was observed on milk quality variables (somatic cell count and fat‐to‐protein ratio). Intensified pasture management increased milk and component production, yielding a land‐saving effect of 2.7 ha per ha of intensified pasture.