Farmed deer adaptability to the stressors of weaning

The scale and complexity of livestock farming is increasing, with more staff on farm, more requirement for precise human interventions and arguably less buffers in the system. On top of this climatic conditions are becoming more extreme and variable. These factors combine to provide a risk to the welfare, health, and productivity of our farmed livestock. A climatic event or interruption, or a management error (e.g. missed animal health treatment), can create stressors and have negative impacts on our livestock. There are ways to de-risk this within a farm system, one of these is to have animals that are robust and adaptable to these short-term disruptions or perturbations to their lives. This is a slightly different concept to resilience, which is the ability to bounce back from such an environmentally induced shock, potentially of more interest is if, or how the animal and the system can ride out such challenges. The complexity of farm systems, with the constant change in animal management and genetics means that it can be difficult to understand what impacts we have made on the various components of the system. Knowing if we have made our animals more, or less fit for purpose, or the challenges and opportunities under different stressors should inform future animal selection, management interventions, or farm system design. Farmed deer have been under genetic selection for farming for a much shorter time than our traditional livestock species. In their recent wild past, there was a strong natural selection for fitness, albeit some traits or behaviours (e.g. predator avoidance) may not be so useful in a farmed environment. Two of the most common stressors on deer in a farmed environment are nutritional and disease stress, with the former potentially triggering the later. To investigate the adaptability of farmed deer in New Zealand a trial with a nutritional stressor treatment associated with weaning was undertaken during Autumn of 2023.