Body weight and feed and water deprivation time predict cattle body weight loss from transportation

Context The body weight of cattle decreases during transport. The decrease in weight is associated with reduced gut fill, dehydration and weight loss. Cattle experience thirst and hunger during long journeys. To the best of the author’s knowledge, a systematic review and meta-analysis of factors that contribute to weight loss during transport has not been previously published. A model that predicts body weight loss in cattle during transport may assist producers understand the key drivers of weight loss and identify opportunities where body weight loss can be reduced during the journey. Aim The aim of this review is to identify factors associated with cattle live-weight loss during road transport and to develop a predictive model to assist industry stakeholders estimate weight loss. Methods A systematic review of the literature found 26 studies suitable for inclusion in the meta-analysis, based on inclusion and exclusion criteria. Moderators were initially screened using univariable multilevel meta-regression analyses. A backward selection approach was used to construct the final multivariable model, with moderators sequentially removed based on statistical significance and model fit. Key results Feed and water deprivation time (P = 0.001) and the initial body weight of the animal (P = 0.001) were significant modifiers of body weight loss. Treatment (transport or no transport) (P = 0.3744), genetic type (P = 0.3417), region (P = 0.4501), sex (P = 0.6069) and feed type (P = 0.8101) were not significant modifiers in the univariable analysis and were excluded from the final model. Conclusions Initial body weight and the duration of feed and water deprivation are significant predictors of body weight loss. Road transportation was not a significant modifier of the relationship between feed and water deprivation and body weight loss. Implications Reducing the total time that cattle are deprived of feed and water is likely to reduce weight loss during transportation. Therefore, providing cattle with ad libitum access to feed and water as close as possible to loading may help minimise weight loss. The predictive model, based on the results of the meta-analysis, can assist industry stakeholders predict cattle body weight loss for an intended journey.