Research Note: Injurious pecking in fattening turkeys (Meleagris gallopavo f. dom.). Video analyses of triggering factors and behavioral sequences in small flocks of turkey males
Injurious pecking is one of the main welfare issues in fattening turkey husbandry. Birds pecked by conspecifics can suffer from serious injuries which may even lead to the death of the victimized animals or require their culling. In the present study the behavior of male turkeys was documented day and night using video recordings throughout the entire fattening period of 19 weeks. Thus, when a turkey was found injured or dead in the barn, a retrospective analysis of video recordings was carried out to clarify the circumstances surrounding the death or injuries of the bird in the present study. In three fattening trials with a total of 1,620 male turkeys with intact beaks, 41 birds (2.5 %) were found either seriously injured [n = 24] or dead [n = 17] in the barn as a result from conspecific pecking. The detailed evaluation of the video recordings showed that the onset of injurious pecking was mainly in the afternoon after the last daily visual controls of animals and that one third of the dead found animals died a natural death without any pecking incidents. The duration of injurious pecking directed against a certain conspecific was on average 794 min, ranging from 84 min to 1,437 min, i.e. up to almost an entire day. Pecking activities lasting more than 10 hours were interrupted from the light regime between dusk and dawn, but continued with the onset of light in the morning. Duration of pecking events decreased with age (p = 0.031). If the victims laid down or were impaired in their mobility, they would be surrounded by up to ten turkeys that would still be forcefully pecking at the occipital and neck area of the badly injured or moribund birds.