Weaning and castration in beef calves

The present work included three trials to investigate the effects of abrupt separation on male and female beef calves of different ages (Trial 1; n=80) and the impact of the timing of this weaning method and the Burdizzo castration on male beef calves (Trial 2; n=32 and Trial 3; n=111). In each trial, vocalization activity, behavior and growth performance of the calves were studied, additionally several blood (Trial 2) and slaughter traits (Trial 2 and 3) were collected. In Trial 1, vocalization and behavior indicated that weaning had a greater impact on the younger weaned calves (6 months of age) compared to calves weaned at 8 months of age. Furthermore performance data suggest to prefer the later weaning age. In Trial 2, treatments were defined either as weaning conducted simultaneously castration or weaning 4 weeks after castration . Thereby the blood traits, such as Haptoglobin, did not clearly indicate the stressors weaning and castration, potentially due to the sampling times. Castration seemed to reduce vocalization activity, but did not influence behavior after weaning. Although there was an advantage of weaning simultaneously castration in terms of a 3-weeks growth rate after castration, treatment differences disappeared till slaughter. In Trial 3, treatments were defined as either weaning conducted simultaneously castration or weaning 8 weeks before castration . Results indicated, that vocalizations are induced by weaning rather than by castration. Furthermore, castration reduced vocalization activity and lying behavior. Therefore vocalization activity did not conclusively indicate the well-being status of the calves, when weaning and castration simultaneously occurred. Behavior was influenced by castration and weaning as well as housing conditions. Similar to Trial 2, concerning a short-time growth rate after castration the treatment weaning + castration seems to be preferential, whereas there was no treatment effect on the slaughter traits. Further studies should be executed to analyze the present findings. Thereby stress indicators to be observed should be modified. From the results of this thesis it can be presumed that timing of weaning and castration have to be differentiated for the individual production conditions, concerning housing, feeding and marketing management.