Research into etiologie, preventive and therapeutic intervention of feather damaging behaviour in parrots

Feather damaging behavior (FDB), also referred to as feather plucking, feather picking or pterotillomania, is a common behavioural disorder in captive parrots, with an estimated prevalence of 10-15% throughout the parrot population. Birds with FDB either chew, pluck, bite or pull their feathers, thereby inflicting significant damage to their plumage, particularly in the areas that are easily accessible to the beak (i.e., neck, chest, flanks, inner thighs and wings). Although the consequences of this self-inflicted feather damage may be solely  aesthetic, medical issues may also arise due to alterations to the birds’ thermoregulatory abilities and metabolic demands, hemorrhage and/or (secondary) infections. Once parrots display FDB, it is often difficult to break their habit, with treatments generally yielding disappointing results. As a result, parrots with FDB frequently end up being euthanized or relinquished to a shelter or sanctuary.

Similar to stereotypies, FDB may be classified among the abnormal repetitive behaviours (ARBs),which are defined as behaviours that are inappropriate, repetitive and unvarying in either goal or motor pattern. These behaviours often develop in captive animals upon chronic exposure to stressing or aversive stimuli, and/or due to the inability to perform their species-specific behaviours. Parrots in particular appear prone to developing these disorders due to their high-level cognitive abilitiesand the relatively limited time span that they have been bred in captivity which generally classifies them as non-domesticated species. These characteristics often render the captive living environment inadequate to meet the parrots’ social, cognitive and behavioural needs, thereby leading to the development of ARBs and compromising their welfare. In addition to socio-environmental factors of the current living environment, previous life experiences (including rearing methods), and intrinsic factors (e.g., temperament traits and genetic, neurobiologic and neuroendocrine factors) may also play a role.

The research of Yvonne van Zeeland, for which she obtained her PhD in June 2013, aims to gain further insight in the behaviour and needs of (feather damaging) parrots, which may subsequently help to elucidate the pathogenesis and associated (extrinsic and intrinsic) risk factors, and design preventive and therapeutic strategies to reduce the overall occurrence of FDB in the captive parrot population. The studies described in this thesis particularly focus on the Grey parrot (Psittacus erithacus erithacus), as this appears to be one of the most commonly affected species. In future, results of her studies may, however, also be applicable to other parrot species and help to improve the welfare of these birds.

Other research projects

In addition to this research, Yvonne is also actively involved in larger and smaller research projects into clinically relevant topics in birds and small mammals, including studies into hyperadrenocorticism (adrenal gland disease), blood pressure measurement and welfare of ferrets (the latter as a co-supervisor of PhD student Marsha Reijgwart), development and clinical use of supraglottic airway devices in rabbits and guinea pigs (a collaborative study with DocsInnovent) and studies into nebulization techniques in birds.