Evaluation of growth of intact vs castrated Braford calves at different ages

Abstract

We compared entire versus castrated male Braford calves, at different ages of castration, with the objective to evaluate this effect on growth by means of the total and daily weight gain. Twenty-eight Braford male suckling calves, were used. Animals were randomly divided into groups of 7 individuals: C45: castrated at 45 days of age; E45: entire, with 45 days of age; C90: castrated at 90 days of age and E90: entire, with 90 days of age. Individual weights were recorded on day 0 (castration’s day) and then on days 15, 30 and 45. Castration was performed by means of surgery. The studied variables were total gain (GT, kg of live weight) and average daily gain (GMD, kg/day). Descriptive statistics, analysis of variance (ANOVA) and Duncan’s test (p<0.05) were performed, considering as the main effect the age of castration (45 and 90 days), with the intact males as controls. The means for GT were: C45: 34.86 kg; E45: 37.29 kg; C90: 51.14 kg and E90: 44.29 kg. For GMD, they were: C45: 0.58 kg; E45: 0.62 kg; C90: 0.85 kg and E90: 0.74 kg. The ANOVA test showed significant differences for both variables, GT (p=0.0156) and GMD (p=0.0157), with C90 being the higher, considering the other groups. In particular, E90 group obtained intermediate values between C90 and calves of 45 days. Between C45 and E45, no significant differences were found for both variables. We conclude that a recommended castration time should be close to three months of age, since at 45 days of age live weight was more affected by the surgical technique.