The effects of environmental enrichment and intermittent lighting on the behaviour and welfare of male domestic turkeys

Under commercial and experimental conditions, domestic turkeys frequently c ause injuries to pen-mates, sometimes fatally, by repeated pecking. Environ mental enrichment or intermittent lighting patterns might be used to mitiga te such injurious pecking. This study examined the responses to four treatm ents (two rooms/treatment) of eight groups of 50 non-beak trimmed, male dom estic turkeys from day-of hatching to 21 weeks of age. One treatment, 'Cont rol' birds, were reared under conditions approximating commercial rearing; the other treatments were Enriched (many varied pecking substrates) and two intermittent lighting patterns one of which provided a long duration scoto period (12 h/24 h) whereas the other provided eight, 2 h scotoperiods/24 h. Environmental enrichment significantly reduced injuries due to wing and ta il-pecking compared to Control birds and increased the latency to sit after 2.5 min forced standing (arguably indicating improved musculo-skeletal fun ction). The intermittent lighting pattern without the extended scotoperiod also significantly reduced injuries due to wing and tail-pecking, but tende d to increase injuries due to head pecking. In addition, in this treatment 40% of the birds were visually non-reactive possibly indicating blindness. Intermittent Lighting with the 12 h scotoperiod had no significant effect o n injuries due to pecking and resulted in only 5% of the birds being visual ly non-reactive, despite both intermittent lighting patterns providing the same total duration of light (8 h/24 h). It is concluded that although inte rmittent lighting patterns offered limited benefits in terms of reducing so me types of injurious pecking, these were negated by other compromises of w elfare. In addition, providing domestic turkeys with appropriate environmen tal enrichment improved their welfare in several aspects related to injurio us pecking and possibly,:musculo-skeletal function and blindness. (C) 1999 Elsevier Science B.V. All rights reserved.