The influence of stocking density on behaviour, health, and production in commercial fattening turkeys-a review

1. This paper reviews literature on the effects of stocking density on behaviour, health, and production in intensively housed fattening turkeys. 2. Worldwide, there are various regulations and recommendations on the maximum stocking density. While stocking density can be determined based on the space covered by the body, a more appropriate method considers space requirements for natural behaviour. Turkeys are less likely disturbed at low stocking density as seen by increased sitting, lying, and preening behaviours compared to animals housed at high stocking density. Furthermore, lower stocking density together with smaller group size, species-appropriate light conditions and suitable structuring of barn housing are repeatedly mentioned as good strategies to prevent injurious pecking. 3. Increased stocking density - in terms of weight and animal number per floor area - is related to increased litter moisture, which can have negative impact on animal health. High stocking density can also lead to poor body mass gain and increased mortality, which are not only indicators of impaired welfare but also of economic interest. 4. Based on the available scientific literature and economic aspects with regard to the above criteria, a maximum stocking density for turkeys appears to be 36-a maximum of 40 kg live weight per m2 of usable floor space. However, the number of animals per square space should also be limited to avoid increased litter moisture and reduced health.