UC Davis

The weaning period is often regarded as one of the most challenging times in a beef calf’s life where they must establish independence from their dam. Rather than abruptly severing the maternal-offspring bond, alternate weaning methods were developed to make this process more gradual. In Chapter 1, I introduced and compared different approaches for weaning beef calves in the United States. Two-stage methods, such as fence line and nose flap were developed for reducing the behavioral and physiological stress response that calves undergo by providing a physical barrier, either a fence or nose flap, that allows the calf to be weaned from milk prior to separation from the dam. Although these are both thought to have a net positive effect on calf welfare, the objective of the current study was to explore both positive and negative consequences. In Chapter 2, one potential tradeoff made when utilizing a nose flap for weaning – injuries was investigated. While a nose flap has been shown to be beneficial in minimizing the behavioral distress response, there are several types commercially available, and recent findings showed that they cause injuries on the calf’s nasal septum. The objectives were to (1) identify if a nose flap created injuries on the nasal septum, (2) explore whether factors like calf body weight or septum size could be used to predict the incidence of injuries or flap loss; and (3) create a binomial scoring system that could use to reliably score characteristics observed. While no injuries were observed in calves that had not worn the nose flap, it was found that after 7 d of wearing them, injury was ubiquitous at the time of removal and still visible at least 6 d afterwards. Injuries and flap loss were widespread; therefore, body weight or septum size of the calf had no effect. Wound descriptions were scored in duplicate by a trained observer (damage, impression, and blood; 97%, 91%, and 100% agreement between first and second evaluations, respectively), indicating that scoring system proposed is repeatable. The outcomes of this research have the potential to improve beef calf welfare and provide a valuable basis for industry recommendations regarding weaning methods for calves. Injuries inflicted from a nose flap may counteract the benefits to this method, making it less advantageous than other two-stage alternatives, like fence line weaning.