Sham dustbathing

Last updated

Sham dustbathing is a behaviour performed by some birds when kept in cages with little or no access to litter, during which the birds perform all the elements of normal dustbathing, but in the complete absence of any substrate. [1] [2] [3] This behaviour often has all the activities and temporal patterns of normal dustbathing, i.e. the bird initially scratches and bill-rakes at the ground, then erects its feathers and squats. Once lying down, the behaviour contains four main elements: vertical wing-shaking, head rubbing, bill-raking and scratching with one leg. Normal dustbathing is a maintenance behaviour whose performance results in dust collecting between the feathers. The dust is then subsequently shaken off which reduces the amount of feather lipids and so helps the plumage maintain good insulating capacity and may help control of ectoparasites. [4]

Contents

Terminology

Sham dustbathing is sometimes referred to as "vacuum dustbathing". In the Konrad Lorenz model of behaviour regulation, vacuum activities occur when motivation for a certain behaviour builds to a sufficiently high level that the behaviour is performed in the complete absence of relevant stimuli. However, hens "dustbathing" on wire floors commonly perform this close to the feed trough where they can peck and bill-rake in the food. [5] Because it seems the birds appear to treat the feed as a dustbathing substrate, the term "sham dustbathing" is more appropriate.

Motivational basis

A hen performing normal dustbathing Hen dustbathing.jpg
A hen performing normal dustbathing

Sham dustbathing, like normal dustbathing, appears to have both internal and external causal factors.

Internal causal factors

Under unrestricted conditions, adult birds dustbathe about every second day, with a diurnal rhythm peaking in the middle of the day, and an average dustbathing bout lasting about 27 minutes. Hens without litter (i.e. an absence of external causal factors) will perform sham dustbathing with a similar temporal pattern. Some hens deprived of litter until they had developed sham dustbathing and then given access to litter, showed sham dustbathing although litter was available. Thus, there is some support for an effect of habit or early experience on sham dustbathing. [1]

Depriving hens of the opportunity to dustbathe results in a rebound when hens are again allowed access to dust. Birds work for access to litter, [6] in which case they sometimes, although not always, dustbathe. There are indications of stress when hens are deprived of the possibility to dustbathe, and if this deprivation is sufficiently long, sham dustbathing behaviour develops.

External causal factors

It has been suggested that the sight of other hens performing the behaviour increases the probability of sham dustbathing, i.e. social facilitation; however, when tested, the sight of stimulus birds had no effect on the sham dustbathing behaviour of test birds. [1] As indicated above, hens "dustbathing" on wire floors commonly perform this close to the feed trough where they can peck and bill-rake in the food, [5] indicating this may be an external causal factor.

Welfare

Sham dustbathing raises questions regarding hen behavior, motivation, and welfare. [6] A study utilized a weighted push-door as the operant method to assess the motivation of adult hens with varying experiences of litter. There was no discernible difference in motivation levels between hens with prior exposure to litter and those without. This suggests that sham dustbathing might not adequately fulfill the hens' needs nor is it perceived as normal dustbathing.[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Debeaking</span> Trimming of a birds beak, usually performed on domesticated birds

Debeaking, beak trimming, or beak conditioning, is the partial removal of the beak of poultry, especially layer hens and turkeys, although it may also be performed on quail and ducks. Most commonly, the beak is shortened permanently, although regrowth can occur. The trimmed lower beak is somewhat longer than the upper beak. A similar but separate practice, usually performed by an avian veterinarian or an experienced birdkeeper, involves clipping, filing or sanding the beaks of captive birds for health purposes – in order to correct or temporarily to alleviate overgrowths or deformities and better allow the bird to go about its normal feeding and preening activities. Amongst raptor-keepers, this practice is commonly known as "coping".

<span class="mw-page-title-main">Domestic turkey</span> Species of bird

The domestic turkey is a large fowl, one of the two species in the genus Meleagris and the same species as the wild turkey. Although turkey domestication was thought to have occurred in central Mesoamerica at least 2,000 years ago, recent research suggests a possible second domestication event in the area that is now the southwestern United States between 200 BC and 500 AD. However, all of the main domestic turkey varieties today descend from the turkey raised in central Mexico that was subsequently imported into Europe by the Spanish in the 16th century.

<span class="mw-page-title-main">Broiler</span> Chicken bred for meat

Breed broiler is any chicken that is bred and raised specifically for meat production. Most commercial broilers reach slaughter weight between four and six weeks of age, although slower growing breeds reach slaughter weight at approximately 14 weeks of age. Typical broilers have white feathers and yellowish skin. Broiler or sometimes broiler-fryer is also used sometimes to refer specifically to younger chickens under 2.0 kilograms, as compared with the larger roasters.

An ethogram is a catalogue or inventory of behaviours or actions exhibited by an animal used in ethology.

<span class="mw-page-title-main">Battery cage</span> Agricultural technology

Battery cages are a housing system used for various animal production methods, but primarily for egg-laying hens. The name arises from the arrangement of rows and columns of identical cages connected, in a unit, as in an artillery battery. Although the term is usually applied to poultry farming, similar cage systems are used for other animals. Battery cages have generated controversy between advocates for animal welfare and industrial producers.

<span class="mw-page-title-main">Poultry farming</span> Part of animal husbandry

Poultry farming is the form of animal husbandry which raises domesticated birds such as chickens, ducks, turkeys and geese to produce meat or eggs for food. Poultry – mostly chickens – are farmed in great numbers. More than 60 billion chickens are killed for consumption annually. Chickens raised for eggs are known as layers, while chickens raised for meat are called broilers.

Vacuum activities are innate fixed action patterns (FAPs) of animal behaviour that are performed in the absence of a sign stimulus (releaser) that normally elicit them. This type of abnormal behaviour shows that a key stimulus is not always needed to produce an activity. Vacuum activities often take place when an animal is placed in captivity and is subjected to a lack of stimuli that would normally cause a FAP.

<span class="mw-page-title-main">Dust bathing</span> Animal behavior

Dust bathing is an animal behavior characterized by rolling or moving around in dust, dry earth or sand, with the likely purpose of removing parasites from fur, feathers or skin. Dust bathing is a maintenance behavior performed by a wide range of mammalian and avian species. For some animals, dust baths are necessary to maintain healthy feathers, skin, or fur, similar to bathing in water or wallowing in mud. In some mammals, dust bathing may be a way of transmitting chemical signals to the ground which marks an individual's territory.

<span class="mw-page-title-main">Feather pecking</span> When one bird repeatedly pecks at the feathers of another

Feather pecking is a behavioural problem that occurs most frequently amongst domestic hens reared for egg production, although it does occur in other poultry such as pheasants, turkeys, ducks, broiler chickens and is sometimes seen in farmed ostriches. Feather pecking occurs when one bird repeatedly pecks at the feathers of another. The levels of severity may be recognized as mild and severe. Gentle feather pecking is considered to be a normal investigatory behaviour where the feathers of the recipient are hardly disturbed and therefore does not represent a problem. In severe feather pecking, however, the feathers of the recipient are grasped, pulled at and sometimes removed. This is painful for the receiving bird and can lead to trauma of the skin or bleeding, which in turn can lead to cannibalism and death.

<span class="mw-page-title-main">Abnormal behaviour of birds in captivity</span>

Abnormal behavior of birds in captivity has been found to occur among both domesticated and wild birds. Abnormal behavior can be defined in several ways. Statistically, 'abnormal' is when the occurrence, frequency or intensity of a behaviour varies statistically significantly, either more or less, from the normal value. This means that theoretically, almost any behaviour could become 'abnormal' in an individual. Less formally, 'abnormal' includes any activity judged to be outside the normal behaviour pattern for captive birds of that particular class or age. For example, running rather than flying may be a normal behaviour and regularly observed in one species, however, in another species it might be normal but becomes 'abnormal' if it reaches a high frequency, or in another species it is rarely observed and any incidence is considered 'abnormal'. This article does not include 'one-off' behaviours performed by individual birds that might be considered abnormal for that individual, unless these are performed repeatedly by other individuals in the species and are recognised as part of the ethogram of that species.

Vent pecking is an abnormal behaviour of birds performed primarily by commercial egg-laying hens. It is characterised by pecking damage to the cloaca, the surrounding skin and underlying tissue. Vent pecking frequently occurs immediately after an egg has been laid when the cloaca often remains partly everted exposing the mucosa, red from the physical trauma of oviposition or bleeding if the tissue is torn by her laying an egg. Vent pecking clearly causes pain and distress to the bird being pecked. Tearing of the skin increases susceptibility to disease and may lead to cannibalism, with possible evisceration of the pecked bird and ultimately, death.

Animal welfare science is the scientific study of the welfare of animals as pets, in zoos, laboratories, on farms and in the wild. Although animal welfare has been of great concern for many thousands of years in religion and culture, the investigation of animal welfare using rigorous scientific methods is a relatively recent development. The world's first Professor of Animal Welfare Science, Donald Broom, was appointed by Cambridge University (UK) in 1986.

<span class="mw-page-title-main">Cannibalism in poultry</span>

Cannibalism in poultry is the act of one individual of a poultry species consuming all or part of another individual of the same species as food. It commonly occurs in flocks of domestic hens reared for egg production, although it can also occur in domestic turkeys, pheasants and other poultry species. Poultry create a social order of dominance known as pecking order. When pressure occurs within the flock, pecking can increase in aggression and escalate to cannibalism. Cannibalism can occur as a consequence of feather pecking which has caused denuded areas and bleeding on a bird's skin. Cannibalism can cause large mortality rates within the flock and large decreases in production due to the stress it causes. Vent pecking, sometimes called 'cloacal cannibalism', is considered to be a separate form of cannibalistic pecking as this occurs in well-feathered birds and only the cloaca is targeted. There are several causes that can lead to cannibalism such as: light and overheating, crowd size, nutrition, injury/death, genetics and learned behaviour. Research has been conducted to attempt to understand why poultry engage in this behaviour, as it is not totally understood. There are known methods of control to reduce cannibalism such as crowd size control, beak trimming, light manipulation, perches, selective genetics and eyewear.

<span class="mw-page-title-main">Furnished cage</span>

A furnished cage, sometimes called enriched cage, colony cage or modified cage, is a type of cage used in poultry farming for egg laying hens. Furnished cages have been designed to overcome some of the welfare concerns of battery cages whilst retaining their economic and husbandry advantages, and also provide some of the welfare advantages over non-cage systems. Many design features of furnished cages have been incorporated because research in animal welfare science has shown them to be of benefit to the hens.

<span class="mw-page-title-main">Preference test</span> Experiment in animal behavior

A preference test is an experiment in which animals are allowed free access to multiple environments which differ in one or more ways. Various aspects of the animal's behaviour can be measured with respect to the alternative environments, such as latency and frequency of entry, duration of time spent, range of activities observed, or relative consumption of a goal object in the environment. These measures can be recorded either by the experimenter or by motion detecting software. Strength of preference can be inferred by the magnitude of the difference in the response, but see "Advantages and disadvantages" below. Statistical testing is used to determine whether observed differences in such measures support the conclusion that preference or aversion has occurred. Prior to testing, the animals are usually given the opportunity to explore the environments to habituate and reduce the effects of novelty.

<span class="mw-page-title-main">Consumer demand tests (animals)</span>

Consumer demand tests for animals are studies designed to measure the relative strength of an animal's motivation to obtain resources such as different food items. Such demand tests quantify the strength of motivation animals have for resources whilst avoiding anthropomorphism and anthropocentrism.

<span class="mw-page-title-main">Comfort behaviour in animals</span>

Comfort behaviours in animals are activities that help maintain the pelage, feathers, integuement or musculoskeletal system and increase the physical comfort of the animal.

<span class="mw-page-title-main">Social facilitation in animals</span>

Social facilitation in animals is when the performance of a behaviour by an animal increases the probability of other animals also engaging in that behaviour or increasing the intensity of the behaviour. More technically, it is said to occur when the performance of an instinctive pattern of behaviour by an individual acts as a releaser for the same behaviour in others, and so initiates the same line of action in the whole group. It has been phrased as "The energizing of dominant behaviors by the presence of others."

<span class="mw-page-title-main">Chris Sherwin</span> English veterinary scientist (1962–2017)

Christopher M. Sherwin was an English veterinary scientist and senior research fellow at the University of Bristol Veterinary School in Lower Langford, Somerset. He specialised in applied ethology, the study of the behaviour of animals in the context of their interactions with humans, and of how to balance the animals' needs with the demands placed on them by humans.

References

  1. 1 2 3 Olsson, I.A.S., Keeling L.J. and Duncan, I.J.H., 2002. Why do hens sham dustbathe when they have litter? Applied Animal Behaviour Science, 76: 53–64
  2. Merrill, R.J.N., Cooper, J.J., Albentosa M.J. and Nicol, C.J., 2006. The preferences of laying hens for perforated Astroturf over conventional wire as a dustbathing substrate in furnished cages. Animal Welfare, 15:173–178
  3. van Liere, D.W., 1992. The significance of fowls' bathing in dust. Animal Welfare, 1:187–202
  4. Olsson, I.A.S. and Keeling, L.J., 2005. Why in earth? Dustbathing behaviour in jungle and domestic fowl reviewed from a Tinbergian and animal welfare perspective. Applied Animal Behaviour Science, 93: 259-282
  5. 1 2 Lindberg, A.C. and Nicol, C.J. 1997. Dustbathing in modified battery cages: is sham dustbathing an adequate substitute? Applied Animal Behaviour Science, 55: 113–128
  6. 1 2 Wichman, A. & Keeling, L.J., 2008. Hens are motivated to dustbathe in peat irrespective of being reared with or without a suitable dustbathing substrate. Animal Behaviour, 75: 1525-1533