Management strategies to improve temperament and reproductive index in beef cattle

Abstract

The aim with this study is to evaluate the effect of controlled suckling on reproductive performance of Bos indicus and on the temperament of mother-offspring. It will be utilized 50 cows Bos indicus (Nellore and Guzerat), with average age 46.88 ± 7.79 months and accompanied by their calves, and 2 bulls (Guzerat) with bull: cow ratio 1: 25. The breeding season will have a total duration of 90 days. The animals will distribute into 2 treatments: T1-cows submitted to the ordinary management (continuous suckling) and T2- cows submitted to controlled suckling. The animals will be placed in two different paddocks. Cows and calve´s temperament will be evaluated every 30 days during breeding season and 30 -60 days after the end of the breeding season. Four temperament´s measures will be used: 1) flight speed, 2) reactivity test in squeeze chute, 3) crush score, 4) flight distance. Every 30 days and during the whole period of the breeding season the cow´s body condition score will be evaluated and the body weight of the calves will be estimated using zoometric tape. A pregnancy diagnosis will be done after 45 days of the beginning of the breeding season and after 30 days of the end of it, using ultrasonography equipment. Data will be firstly submitted to exploratory analyses, generating means, standard deviations and graphs. After analysis of normality, but if not normal distributed, data will be analysed to univariate nonparametric using the Friedman test, for dependent variables. The difference between the experimental groups will be analyzed by Mann Whitney test for independent variable.