Milk Stability: Physicochemical and Performance Parameters in Highly Technified Holstein and Jersey Herds.

Low stability of milk causes losses to the farmers and dairy industry by increasing milk rejection and compromising heat treatment, respectively. The stability of milk in ethanol and its relationship with the acidity and physicochemical traits of milk from Holstein and Jersey breeds were evaluated. Titratable acidity, ethanol test, ionized calcium concentration (iCa), milk chemical composition, and the milk production, parity, and body condition score of cows were analyzed. Milk characteristics and performance parameters showed that herds were of high genetic value and were raised in high-tech systems. Milk stability was high in the two breeds (> 80% v/v). Milk production and composition were similar in low, medium, and high stability milk in both breeds. Augments in parity, days in milk, iCa, and acidity in the Holstein breed, and total solids in Jersey increased the occurrence of less stable milk. Ionized calcium was the main factor associated with low milk stability in both breeds.