When is animal feeling/suffering at the crux of animal welfare concerns?
- When loss of function/physiological disturbance is and is not a welfare problem
- Society legislates to protect and safeguard animals and not plants even though they can still have health problems and unnatural lives.
What are the 5 freedoms?
- Freedom from pain, injury or disease
- Freedom from hunger and thirst
- Freedom from discomfort
- Freedom from fear and distress
- Freedom to express normal behaviour – to avoid frustration
Name the 2 scientific approaches to measuring animal welfare.
Motivation and preference approach
Welfare indicators approach
What is assumed about the motivation and preference approach?
Animals suffer if denied resources that they are strongly motivated to obtain or if exposed to stimuli that they will work hard to avoid.
What is an example of the motivation and preference approach?
Preference test: decision box that animal can go to A or B from. For example: flooring for caged hens = fine gauge wire preferred to sturdy wire in contrast to what was expected.
What are the problems with the motivation and preference approach?
- Based on human consumer behaviour
- Testing in groups may cause animals to just follow on from each other.
- Finite number of resources offered.
- Variability of preference between individuals.
- Animals may show short term preferences which may do them harm in the long term, such as eating high fat foods.
- There is little cost of exploring the preferences and may not actually reflect the choice as a preference.
How important is social contact for a pig, for example, given motivation and preference testing?
4 pigs trained to press a panel in a test pen to get food:
- Access to 25g food
- 15 s access to a companion
- 15 s access to an empty pen
- Cost of resources varied by increasing the number of panel presses required for each access to a resource.
- Demand for food remains fairly stable as prices increase in inelastic demand (a benchmark for an important resource
- Demand for social contact is more elastic
- Demand for the empty pen is most elastic
How aversive is restraint and mobilisation for a sheep?
Sheep trained at the end of a runway they will be let free to go, restrained for 2.5 mins, restrained and wired up or restrained, wired up and electro immobilised:
- Measurements taken of how hard the animals work to resist movement down the runway/how long it takes to be pushed down.
- Consumer demand type approach can be used to show how hard animal work to avoid as well as to access.
Are there any problems with using short-tern tests of consumer demand?
- Animals may be able to gain access to the resources under test when they are outside the test situation, and so their behaviour in the test may not reflect ‘true’ demand
- The duration of the test/exposure to resources may not be adequate to allow full expression of the associated behaviour
- An alternative approach is to make the tests part of the animal’s home environment
What is assumed with physical and physiological welfare indicators?
- They biological responses of animals in apparently unpleasant situations reflect the degree of suffering they experience.
- Biological changes occurring in humans reporting feeling such as fear, pain, anxiety, happiness may also be sued as indicators of similar states in animals.
What is the logic behind physical and physiological welfare indicators?
- We identify a situation as being unpleasant or use motivation and preference approach to do this.
- We measure biological responses to this situation.
- Any consistent responses to a number of unpleasant situations are taken as indicators of poor welfare and suffering.
- These welfare indicators are then used to assess the impact of new situations on welfare and suffering.
What are the criticisms of physical and physiological welfare indicators?
- This could be criticised as anthropomorphic.
- There is evolutionary continuity: cross species similarities in anatomy, physiology, morphology and possibly mental processes
- Human as our only model of the links between behaviour, physiology and mental experience
What are welfare indicators?
Can provide information on the extent to which an animal’s physical and physiological systems are disturbed. If used carefully and critically, they may also be able to act as proxy measure of mental state and suffering.
Name some measures of physiological stress responses used as welfare indicators.
Heart rate
Blood pressure
Adrenaline
Cortisol
Corticosterone
What does measuring cortisol tell us about welfare?
- Hypothalamic-pituitary-adrenal axis
- When a stressor arrives, corticotropin releasing hormone, CRH flows from the hypothalamus to the pituitary gland and is released into the blood stream.
- Adrenocorticotropic hormone, ACTH travels through the blood to the adrenal glands
- Release of cortisol/corticosterone
- This has an affect on major organs in terms of energy production and has a negative feedback on the brain to decrease CRH release
- Cortisol is used as an indicator of the stress response an animal is showing.
Why is measuring other indicators important?
Cortisol levels fluctuating may be due to other factors other than stress or pain.
Give 2 examples of behavioural welfare indicators.
Stereotypic licking
Biting pen fittings
How long after the onset of stress does blood cortisol rise due to restraint and insertion of needle?
2 minutes within this window before cortisol begins to rise.
Name 5 other ways to collect cortisol from samples without disturbing the animal.
Urine
Faeces
Saliva
Hair
Milk
How can behaviour be a sign for poor welfare?
- See also distress, pain, sickness/illness
- Abnormal behaviour? Often but not always
How can abnormal behaviour be adaptive with no welfare implications?
- When they are learnt, adaptive modifications, where an intended functional goal is achieved
- Prematurely weaned calves teat suckling for milk, rats learning to press lever for food
- Can indicate a learnt and adaptive behavioural modification in an environmental that differs to its natural environment
What can abnormal behaviour indicate?
Failed adaptation and become maladaptive – likely poor welfare
How can pain be clinically assessed?
- Visual analogue scaling – no pain to pain as severe as possible
- Behaviour scoring – back arch, stagger/fall, writhe, twitch
Behavioural scoring gives a higher success rate in detection of pain
Give an example of gait analysis and lameness scoring.
Gait score 1: sound – walks with a smooth and fluid locomotion with flat back and even steps.
Gait score 2: imperfect locomotion – walks with a slightly uneven gait and slight joint stiffness but is not lame.
Gait score 3: mildly lame – walks with shortened strides, an arched back and a slight limp.
Gait score 4: moderately lame – walks with an obvious limp, a severely arched back and a slight head bob.
Gait score 5: severely lame – unable to bear weight on at least one limb and/or must be vigorously encouraged to stand or move, extremely arched back when standing and walking.
