Effects of Environmental Enrichment on Turkey Behavior, Welfare and Walking Ability

Injurious pecking, aggression, footpad dermatitis and leg abnormalities have been identified as major welfare issues in commercial turkey production, which lead to culling and mortality, downgraded carcass value and economic losses due to decreased productivity and carcass damage. Injurious pecking includes aggressive pecking (head pecking), feather pecking, and cannibalism. Aggressive pecking is related to aggression and is more prevalent in males than females. Feather pecking consists of non-damaging gentle feather pecking and severe feather pecking that can cause feather, skin and tissue damage, and even death in extreme cases. Common methods to control injurious pecking include infrared beak treatment and reduced light intensity, but those methods can result in inconsistent effects on feather condition and negative affect eye development. Footpad dermatitis and leg abnormalities can lead to lameness and an inability of turkeys to access feed and water. Environmental enrichment, which is the modification of the environment of captive animals to improve their biological functioning, is one alternative way of reducing injurious pecking and potentially improving turkeys’ walking ability. In meat-type poultry production, five types of environmental enrichment are usually used, which include social enrichment, occupational enrichment, physical enrichment, sensory enrichment and nutritional enrichment. For turkeys, some types of physical enrichment such as foraging and pecking enrichment have been found to be most effective in reducing injuries caused by injurious pecking and elevated structures (e.g. platform or straw bale) were effective in promoting locomotive exercise. To address some of the gaps in the knowledge regarding the effects of environmental enrichment on turkey behavior, welfare and walking ability, this study examined 1) age-related changes in welfare and gait when turkeys are provided with different types of environmental enrichment; 2) the effects of different types of environmental enrichment on enrichment usage and injurious pecking behavior; 3) specific behaviors and relative location of turkeys when they interact with different types of environmental enrichment. Data were collected from a total of 420 beak-trimmed tom turkeys housed in 24 littered pens located in two rooms within the same barn. Birds were randomly assigned to six treatment groups with 4 replicate pens per treatment group, including five enrichment groups (straw bale, platform, platform + straw bale, pecking block and tunnel) and a control group (no additional enrichment provided). Welfare measures (wounds on the head, neck, snood, back and tail; beak abnormalities; feather quality; feather cleanliness; and footpad condition) and walking ability (gait) were assessed at 8, 12, 16 and 19 wk. Postmortem footpad condition was assessed at 19 wk. Behavior of turkeys was video recorded at 8, 12 and 16 wk and analyzed using scan sampling. The proportions of turkeys performing target behaviors were determined every 15 min (07:00 h - 22:00 h). Welfare and gait data were analyzed using PROC LOGISTIC with Firth bias-correction. Behavior data were analyzed using PROC GLIMMIX. Better wing feather quality with age was observed in turkeys in the straw bale and tunnel groups. Footpad condition worsened with age for turkeys in all treatment groups except for the straw bale group. Gait worsened with age in all treatment groups while earlier onset of gait problem was observed in turkeys provided with a tunnel or no enrichment (control group). The average proportion of turkeys using the enrichments declined with age. Turkeys provided with a platform + straw bale had the highest levels of enrichment usage, followed by the platform group. Preening and severe feather pecking behavior did not change with age and were unaffected by the type of enrichment provided