Arquivo Brasileiro de Medicina Veterinária e Zootecnia (Feb 2024)
Effects of maternal factors and season on health, growth and reproductive parameters in Holstein young heifers
Abstract
ABSTRACT This observational study describes the short- and long-term effects of maternal factors in 226 Holstein heifers and their offspring. We obtained maternal data and information from the dairy register. Young heifers were assessed in the window of 60 to 105 days of life to perform the Calf Health Scoring System and performance index, and blood samples to measure inflammatory biomarkers. Prospective data on reproduction were obtained from dairy farm registers. The eutocic weight was higher than the dystocic calving heifers. Plasma total protein and weight were higher in the offspring of multiparous dams than in those of primiparous dams. Calves that were born lighter and in summer had lower concentrations of total protein and performance indices. The punctuation of the fecal score was higher in calves born in summer and cold months for BRD. Offspring from multiparous dams born at term exhibited greater precocity in terms of age at first artificial insemination and first parturition. Finally, seasonality at birth affected pregnancy loss and age at first calving. Heifers born in winter had lower rates of pregnancy loss than those born in summer. In addition, these animals were more precocious than animals born during the cold seasons.
Keywords