Applied ethology PDF

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Introduction to animal behaviour Week 10 What is applied ethology? Ethology is the zoological study of animal behaviour, typically in natural contexts. When we apply these techniques to managed environments, humans can benefit in a number of ways, including: a) b) c) d) e)

Improved control Improved production Improved breeding Improved housing Improved welfare

The animals of most use to us are typically found in unnatural environments and have often undergone generations of natural selection. This is why many applied ethologists typically compare the behaviour of wild relatives to their captive descendants. The field of applied ethology is a relatively new one, and many attribute its origin to David WoodGush (1922-1992), sometimes dubbed the ‘forefather’ of Applied Ethology. In the 1950’s Wood-Gush joined the new Poultry Research Centre in Edinburgh as the Head of Ethology. Here, he looked for causal explanations of social and nesting behaviour in poultry. He also set up a group studying the pain caused to animals by husbandry procedures. He was a key member of the Society of Veterinary Ethology, which would later become the International Society for Applied Ethology Stimuli and responses •

Animals are highly adapted to normal (for them) daily, seasonal and yearly cycles.

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They are highly adapted to specific terrain (or type of water, access to the air etc)

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Highly adapted to specific diets, even if a generalist

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Highly adapted to temperatures, atmospheric pressures, Uvc etc

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Highly adapted to a/social group sizes specific to their species

Physical environment The closer stimuli mimics the natural environment the closer (but never exactly) behaviours will match. Huge improvement in environments has narrowed some behavioural differences (but many abnormalities remain). Compared to companion, lab and farm animals very few studies in this area Social environment Conspecifics, but also heterospecifics - Whether raised by parents or not, whether social or not, conspecifics are vital at some point in animals life. Social species Many species learn from their parents: •

Food or foraging skills/decisions

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Mate choice or mating behaviour

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Animals are probably more motivated to reproduce than any other aspect of being alive

Many studies have been done with zoo animals, because there is zero replication they are generally descriptive in nature. In a few cases these can be useful if a) there is no data for their wild counterparts b) the data and conclusions are minimal. Behavioural responses to the zoo environment •

They can also act as baselines to highlight what deviations are and when they occur

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They can tell us if behavioural diversity is further reduced due inbreeding/further habituation of captive life (again a baseline)

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Can help us make the animal look more interesting to the public by promoting behaviours that are ‘interesting’

Management of captive animals Behavioural studies can be used to help improve agriculture, for instance by enhancing sheep reproduction, enhancing cow milk production, improving grazing or helping with diet supplements. However, the most important application of animal behavioural studies is to improve animal welfare. Domestic animals are subjected to complex environments to which they develop a variety of coping methods. However, some environments are so challenging that the animal fails to cope resulting in reduced fitness, perhaps to such an extent that it fails to grow, reproduce, or otherwise be productive or even dies. Therefore, one definition of welfare is the animal’s state as regards its attempts to cope with its environment. In particular, an inability to maintain homeostasis may lead to poor welfare. Animal welfare science developed rapidly in the 1980s and 1990s, focussing on the objective assessment of animal welfare, independent of moral or ethical judgement. Initially these studies were concerned with farm animal welfare, e.g. comparing different systems of management, designs of housing, methods of handling or transportation, and procedures in operations or in slaughter, but have since become concerned with all groupings of animals considered to be sentient. Concepts of welfare have been refined over time, as have our ability to assess it. Good welfare occurs when the individual is able to cope with its environment and is able to experience positive feelings, which can be inferred from physiology, brain state and behaviour. Bad welfare occurs when the individual is unable to cope with its environment. Prolonged failure to cope may lead to failure to grow or reproduce, or even death. However, poor welfare can also occur when the animal is coping but it is taking an extraordinary effort and the implementation of several coping responses to do so. Good welfare can be assessed by: a) considering the extent to which a range of normal behaviour can be shown b) determining what are the positive preferences of such animals and then evaluating how much the preferred resources are available or the preferred actions are possible c) Using indicators of pleasure where these are available. Bad welfare can be assessed by: a)

Reduced life expectancy

b) Reduced ability to grow or breed

c) Body damage d) Disease e) Immunosuppression f)

Physiological attempts to cope

g) Behavioural attempts to cope h) Behavioural pathology i)

Self-narcotisation

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Extent of behavioural aversion shown

k) Extent of suppression of normal behaviour l)

Extent to which normal physiological processes and anatomical development are prevented

To date, preference tests have been used to: a. establish animals’ preferences for housing options (e.g. ambient temperature, lighting, preferred types of bedding and flooring) b. improve the effectiveness of husbandry devices such as loading ramps, nest boxes etc c. clarify how strongly animals will avoid aspects of their husbandry

Management of wild animals Animals such as mice, rats and pigeons are common vertebrate pests, they breed rapidly and frequently colonise new areas. They can cause damage to property, consume resources, transmit diseases, and destroy indigenous flora and fauna. In order to control them, they are often killed, trapped, excluded or repelled. Historically, toxins have been the primary method of control, but this has issues for welfare, and possible contamination of the food web. Instead, various recent studies have been on behavioural deterrence. Behavioural studies have also revealed why some control mechanisms do not work, such as when behavioural resistance to eating novel food stuffs arises. Behavioural studies may also help in the management of endangered species. There is a new movement towards integrating animal behaviour and conservation biology. However, there are currently very few studies in animal behaviour related directly to conservation. Animal research Studies of Animal behaviour have been of major use in animal research. They can improve animal welfare, but also help in the interpretation of the findings. For instance, Barnett and Burn identified a key error in many drug studies ion rats. When drugs were tested, to distinguish experimental groups, scientists often used a traditional an ear-punch on one group. However, ear-punched groups mature faster, not because of the drug effect but because wounded pups get more attention from their mother than the un-punched. This causes them to mature faster.

Companion animals Knowledge of companion animal behaviour can assist in adequate training, numerous studies have shown that pets, or at least the presence of animals, can have medical benefits that are beyond dispute. These range from lowering blood pressure to lessening anxiety and depression and even to faster healing times after surgery. Domestication and extinction The changeable climate caused global extinctions in megafauna, especially in the Americas and Australia where large mammals were frequently becoming extinct, Eurasia escaped, to some degree, these losses allowing humans in these regions access to ‘useful’ mammals before other races. A much higher per cent (18%) of animals were domestic-able compared to the rest of the world. In fact of the 51 large mammals in sub-Saharan African 0 were domesticated. Not a human related problem but an animal behaviour and socio-biology issue. They all possess at least one of the six traits derailing domestication: 1) Diet - It cannot be a carnivore because it takes too much to feed them (not true for aquatic animals) 2) Growth rate - It has to grow quickly so you don't have to spend too much feeding it before you kill and eat it 3) Breeding - It has to be willing to breed in captivity 4) Disposition - Mean and aggressive animals can't be domesticated 5) Tendency to panic - If an animal is likely to panic and become uncontrollable, it will be too dangerous to domesticate it 6) Social structure - It is very helpful if the animal is a herd animal or one that is used to living in a hierarchical society. That way, it will be more likely to obey humans Selection and domestic animals Domestic animals have been selected for juvenile head shape, shortened muzzles etc. Selection for physical traits is related to changes in behaviour. Retaining juvenile traits makes animals more tractable and easier to handle. Neoteny - influenced by changes in a few genes controlling timing of different developmental changes. Domestication in dogs has led to: •

retention of wolf pup traits: barking and yapping

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fragmented ancestral social behaviour patterns of wolf

Over selection for specific traits    

Selection for hair colour and patterns in guinea pigs: resulted in decreased reproduction. Continuous selection for tameness in foxes: reduced maternal behaviour and neurological problems. Breeding Cocker spaniels for broad forehead and prominent eyes: hydroencephaly & inability to raise litters Selection for production traits (leanness) resulted in more excitable temperament piglets

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Cattle with more excitable temperaments have lower weight gains and meat quality problems

Environmental monitoring The behaviour of animals often provides the first clues or early warning signs of environmental degradation. Studies of natural behaviour in the field are vital to provide baseline data for future environmental monitoring (E.g. Anglian water use fish behaviour to monitor for pollution)....