Feather pecking is a behavioural problem, which can be caused by environmental, genetic, or nutritional factors. The common age for feather pecking is during peak egg production, but it can happen earlier and once it starts, it is difficult to control. Feather pecking behaviour can be categorized into different levels based on the severity of the pecking and the body part being pecked: gentle feather pecking without removal of feathers, severe feather pecking leading to feather loss, aggressive pecking especially on head and neck, tissue pecking in featherless areas, and vent pecking. Damaged plumage, reduction in feed efficiency, increased injury, and cannibalism are some potential outcomes of severe feather pecking. Read on to learn more!
- Environmental factors
Feather pecking can be triggered by some environmental factors. Early life experiences shape and strengthen behavioural patterns, perception, and preferences throughout life. Therefore, special attention should be paid during a chicken’s early life to prevent initiation of the feather pecking behaviour. Otherwise, this behavioural problem may re-initiate during the laying phase. Litter plays a significant role in feather pecking development. Since foraging is a natural chicken behaviour, they may spend up to 40% of their day foraging on the ground and early access to a proper litter (e.g. wood shaving) is highly recommended. Providing foraging materials with a continuous quality and friable substrate can control feather pecking. Furthermore, good litter management along with a robust ventilation system are important factors affecting air quality in a poultry barn; air quality has a direct relationship with feather pecking issues. Some studies have shown that high levels of carbon dioxide and ammonia are associated with increased levels of feather pecking. Other environmental stressors such as louder sounds, low temperature (below 20°C), and bright lights could trigger feather pecking and cannibalism in layer flocks.
- Environmental enrichment
Providing environmental enrichment can satisfy birds’ natural behaviour and decrease the prevalence of feather pecking. Using hay bales in barns is an effective approach, attracting birds to peck the bales which satisfies their foraging behaviour and decreases their motivation to peck each other. Providing additional grain or straw in the litter during rearing could decrease feather pecking in the laying phase. Having access to perches provides additional vertical space for the birds, and also provides a location that birds can use to escape from unwanted social interactions. Studies have shown that using perches in aviary and caged systems improves skeletal and muscle health, facilitating hen movement and encouraging natural behaviour. Pullets should have access to perches no later than four weeks of age to prevent the development feather pecking and cloacal cannibalism behaviour. Providing perches at a proper height (70 cm) and during critical learning and development phases can also help to reduce feather pecking.
- Feeding and nutritional management
Feed form is an important part of managing feather pecking behaviour. Feeding pelleted feed compared to mashed feed has been shown to increase feather pecking in layers. A possible explanation could be related to differences in feeding time spent for pellet and mash diets. Pellet feed is consumed more rapidly than mash feed, perhaps leaving extra time for feather pecking. Dietary energy, protein, amino acid levels, minerals, and fiber can affect feather pecking in a flock. A low energy diet may reduce feather pecking by increasing the feeding time, leaving less time for feather pecking. A caution – be sure to keep the dietary energy in the recommended range for layers (2,650 to 2,950 kcal/kg). Dietary fibre helps to maintain normal structure and function of the gastrointestinal tract and prevents cannibalism. Research has recommended dietary fiber at the inclusion level of 123 g/kg feed to control feather pecking. Fibrous ingredients such as oat hulls can be used. Birds fed diets high in insoluble fibre spend more time eating and appear calmer than those fed low-fibre diets. Suboptimal dietary levels of protein, amino acids (especially Methionine, Arginine, Tryptophan), minerals (especially magnesium and sodium) could trigger feather pecking. High levels of dietary Tryptophan (up to 22.6 g/kg feed) have been shown to decrease feather pecking behaviour in some situations. Tryptophan is a precursor for serotonin synthesis. It has been shown that stress and fear can contribute to feather pecking. Stress systems in the body can be regulated by serotonergic systems, meaning that serotonin regulates mood and increases in serotonin level would decrease fear behaviour and feather pecking in birds. Therefore, increasing Tryptophan in the diet can calm down the birds leading to less aggressive behaviour. Last but not least, protein sources can also influence feather pecking behaviour. Research has shown that hens fed diets containing plant protein sources showed more feather pecking compared to those fed with animal-based protein sources. Overall, proper management needs to really focus on preventing the occurrence of feather pecking behaviour rather than treating the problem. Special care should be taken during the younger ages, as once the feather pecking behaviour starts, it is difficult to control. Further, flocks should be carefully monitored for any aggressive behaviour, and managerial and nutritional strategies should be implemented early in the flock’s life to prevent the behaviour.
References
Daigle, C.L. 2017. Controlling Feather Pecking and Cannibalism in Egg Laying Flocks in Egg Innovations and Strategies for Improvements. Academic Press. Pages 111-121.
https://www.sciencedirect.com/science/article/pii/B9780128008799000111
Daigle, C.L., Rodenburg, T.B., Bolhuis, J.E., Swanson, J.C., Siegford, J.M., 2014. Use of dynamic and rewarding environmental enrichment to alleviate feather pecking in non-cage laying hens. Appl. Anim. Behav. Sci. 161, 75–85.
https://www.sciencedirect.com/science/article/abs/pii/S0168159114002573
Drake, K.A., Donnelly, C.A., Dawkins, M.S., 2010. Influence of rearing and lay risk factors on propensity for feather damage in laying hens. Br. Poult. Sci. 51, 725–733.
https://www.tandfonline.com/doi/abs/10.1080/00071668.2010.528751
Lambton, S.L., Knowles, T.G., Yorke, C., Nicol, C.J., 2015. The risk factors affecting the development of vent pecking and cannibalism in free-range and organic laying hens. Anim. Welfare 24, 101–111.
https://www.ingentaconnect.com/content/ufaw/aw/2015/00000024/00000001/art00010
Savory, C.J., Mann, J.S., MaCleod, M.G., 1999. Incidence of pecking damage in growing bantams in relation to food form, group size, stocking density, dietary tryptophan concentration and dietary protein source. Br. Poult. Sci. 40, 579–584.
https://www.tandfonline.com/doi/abs/10.1080/00071669986936
van Krimpen, M.M., Kwakkel, R.P., Reuvekamp, B.F.J., van Der Peet-Schwering, C.M.C., den Hartog, L.A., Verstegen, M.W.A., 2005. Impact of feeding management on feather pecking in laying hens. Worlds Poult. Sci. J. 61, 663–686. https://www.cambridge.org/core/journals/world-s-poultry-science-journal/article/abs/impact-of-feeding-management-on-feather-pecking-in-laying-hens/D5E915C94BB7EA5151722B8DDF6E3AD4
