Welfare Issues

Intensive turkey production does not account for many of the birds' psychological and physiological needs, resulting in welfare concerns.

Turkey chicks are precocial and are sustained by yolk reserves until 3 days of age. Learning to eat and drink appropriately during this time is essential, and it is common for a proportion of chicks to die (starve-out) from failing to learn, hence the use of brooding pens. Chicks' attention can be directed by tapping on the feeders and drinkers, thus simulating the behavior of the absent mother hen.

Space allowance for turkeys is often severely limited. For example, a maximum permissible stocking density of 59.1 kg/m2 has been suggested.1-3-1 This approximates to three adult 20-kg birds having to share 1 m2, despite turkeys of this weight each requiring 1700 cm2 simply to stand without touching another bird.[4] The problems of small space allowance are exacerbated by the major influence of social facilitation if turkeys are to feed, drink, dust-bathe, etc. simultaneously, then resources and space must be available in large quantities to avoid causing frustration.

The lighting manipulations used to optimize production can compromise welfare. Long photoperiods combined with low light intensity can result in blindness from buphthalmia (distortions of the eye morphology) or retinal detachment, and can also result in distortion of the behavioral time budget. Short photoperiods (8 h) can retard sexual development in males, and will also cause turkeys to eat in total darkness, possibly indicating an abnormally high motivation to feed resulting from selection for production characteristics. A photoperiod of 12 16 h is adequate for turkeys to consume their daily feed requirement without any obvious adverse physiological or behavioral consequences. Behavioral studies have shown that turkeys prefer light intensities higher than usually provided under commercial conditions. In addition, low intensities make it difficult for humans to adequately inspect the birds.

Feather-pecking occurs frequently among turkeys and can begin at 1 day of age. This behavior is thought to be redirected foraging behavior, caused by providing birds with an impoverished foraging environment. To reduce feather-pecking, turkeys are often beak-trimmed, which causes acute and possibly chronic pain. Feather-pecking can be considerably reduced, at least in small groups (e.g., 100 birds), by providing supplementary ultraviolet radiation (turkeys are visually sensitive to UV; humans are not), pecking substrates (e.g., straw), and visual barriers to reduce social transmission of this behavior.[5-Other pecking substrates include chains, twine, vegetable matter, or food scattered in the substrate. UV-reflective markings appear on young birds at the same time as feather-pecking becomes targeted toward these areas.[6]

Turkeys also perform head-pecking, which becomes more frequent as they sexually mature. When this occurs in small enclosures with few escape opportunities, the outcome is often rapidly fatal; healthy birds can be killed within 3 hours. Frequent monitoring is therefore essential, particularly of males approaching maturity. Head injuries receive considerable attention from other birds, and head-pecking often occurs after a relatively minor injury has been received during a fight or when lying down. Birds with fresh injuries larger than 1 cm should be closely monitored, and separation should be considered. Individuals being reintroduced after separation are often immediately reattacked it might be impossible to re-introduce head-pecked individuals. Fatal head-pecking can occur even in small (10 birds), stable groups. Turkeys are normally reared in single-sex flocks. If a male is inadvertently placed in a female flock, he may be aggressively victimized (henpecked). Females in male groups will be repeatedly mated, during which it is highly likely she will be injured from being trampled upon.

As with broiler fowl, turkeys often become less agile and experience walking difficulties as they become older. This is due to a variety of diseases, anatomical changes from intensive selection for production traits, and poor husbandry. Sometimes, the difficulty in locomotion can become so severe that birds refuse to walk and will die of starvation or thirst unless intervention occurs. Locomotor problems cause the birds to spend long periods sitting on the substrate, which can lead to breast blisters and hock burns from high nitrogen content in the litter. These have both welfare and economic consequences. Poor litter quality can also cause foot-pad dermatitis, which can affect 98% of the flock.

Turkeys are prone to cardiovascular problems, so any physical exertion for them can be quite traumatic and may result in sudden death. Domestic turkeys should be fed commercially available diets that have been developed to meet their nutritional requirements, although they will also benefit from fresh food as dietary enrichment. Nutrient content, food quality, and feeding regimes must be carefully controlled to prevent leg abnormalities and other health and welfare problems associated with rapid growth rates.

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