Body Weight Tick Burden (Boophilus microplus) Physiological Parameters and Reproductive Efficiency of Crossbred Zebu Cattle

摘要

Body weight at calving, degree of tick load (Boophilus microplus), rectal temperature, respiratory frequency and heart rate were evaluated and correlated to reproductive efficiency in 63 F1 Brown Swiss x Nellore milked animals reared in the tropical region of Peru. Cows were bred by free natural service, and first ovulation was estimated by progesterone measurements. The physiological parameters were registered at morning milking (04.00 to 06.00) at an average air temperature of 22.4±0.9°C.