Work

Effect of group size on pecking-injury prevalence and severity in male fattening turkeys (Meleagris gallopavo f. dom.)

Year: 2026

Type: article

Abstract: Agonistic interactions between fattening turkeys in large flocks often result in injurious pecking. In wild turkeys, ranking fights within familiar sibling groups appear from the 8th week of life, but the attacked bird usually escapes from superior birds. We compared three group sizes of male B.U.T. 6 turkeys (group I: n ≤ 11, group II: n ≤ 34, and group III: n ≤ 45) for performance and prevalence of injurious pecking across three trials over a 20-week fattening period. Temperature and relative humidity were logged. Turkeys were weighed on the 1st, 43rd, and 141st day of life (DOL), feed consumption was recorded after each feeding phase, and birds were inspected twice daily; when pecking injuries occurred, their degree and position were documented. Live weights did not differ among the three group sizes, although feed consumption was lower in group I from feeding phase P2 onward than in groups II and III (P < 0.01). Prevalence of injurious pecking was analyzed for low-grade and for combined moderate- and high-grade injuries. For all severity grades, prevalence was lower in group I than in groups II and III. Prevalence of low-grade injuries differed between all groups (P < 0.0001) with age-group size and age-bird number interactions. Moderate and high-grade injuries differed between groups I and II, between I and III (P < 0.0001), without differences between groups II and III, whereas some age-related differences occurred (P < 0.001), with an age-bird number interaction. Age and number of birds per group along with stocking density and available space, appeared to influence the prevalence of pecking injuries. With increasing age, growth, maturity, and less available space per compartment, agonistic interactions between conspecifics rose, whereas the head region was affected more often than the body, wing, or tail regions.

Source: Poultry Science

DOI: 10.1016/j.psj.2026.108025