Preference Testing & Consumer Demand Flashcards
What insights on conscious perception can measuring animal decisions give us?
Priorities
Sensation
Mood
Give some examples of decision making tests?
Preference test Consumer Demand test Conditioned Place Preference test Threshold test Cognitive Bias test
What do decision making tests help us see?
If the animal is:
Fit and feeling good
Healthy and have what they want
Living according to their nature/telos
Has their 5 freedoms/needs met
What do decision making tests not let us see?
If the animal is coping
If the animal has a life worth living or a good life
This one is debatable
How do you do a preference test?
The animal is given 2 or more options and then you measure an indicator of their preference
What are examples of indicators of preference in preference tests?
Latency to choose
Frequency of interacting with each option
Duration of interacting with each option
Name a historical example of a preference test?
Hughes and Black’s 1973 experiment to see the preference of domestic laying hens for different types of battery cage floors.
What were the findings of Hughes and Black’s 1973 preference test?
The hens preferred a lighter mesh floor than a heavier mesh floor.
This is thought to be due to contact points on the floor that the lighter mesh provided.
What were the results of Burn and Mason’s 2008 rat preference test?
Rats have no preference between freshly cleaned and scent-marked cages.
However the rats did show preference for being with their friends/group, since they’d move around together.
How are non-human animals different to humans?
They have different senses
Why do we need preference tests?
Non-human animals have different sensory capabilities to humans
They help to avoid anthropocentricity and anthropomorphism
What must we be careful to account for when interpreting data from preference tests?
Animal perceptual capabilities are different
Integration of information may be different for animals
How animals express themselves as a motivation
How can preference tests be useful in formalising observations of approach- avoidance behaviour?
It can show us Valence
Animals will usually avoid things they don’t like, but their are exceptions and vice versa
Can preference tests allow us to see what creatures prefer when you can’t use other indicators?
Yes
Give an example of when a preference test allows us to see what creatures prefer when you can’t use other indicators?
Insects are an example of an animal which we’d use preference tests to see their Valence as we can’t use many other indicators to do so
Because preference is subjective what must you do?
Measure indicators to make it objective
What must we be aware of about preferences subjective nature?
Preference is subjective so it’s a personal choice which may not represent other animals
When and who did the first preference test?
Dawkins in 1976
What was Dawkins’ 1976 preference test about?
She wanted to see if hens preferred battery cages or free range systems
What indicator did Dawkins 1976 use?
The speed at which the hen moved from the start box into either an empty cage or an outdoor run
Dawkins measured the latency of approach to the stimulus
What were Dawkins 1976 findings?
Hens used to living outside moved more quickly to the outside run
Battery-kept birds moved more quickly into the battery cages
When hens were familiar with both environments the hens showed no significant preference
This showed that prior experience was really important to hen preference
The hens preferred the familiar and were afraid of the unfamiliar
What are some potential reasons for the lack of difference when the hens were familiar with both environments in Dawkins 1976 experiment?
Maybe hens don’t care where they live
Maybe the need to explore both options was too great
The hens didn’t know which scenario to explore first
Maybe the hens like having both options on different days
Maybe speed of running wasn’t the best measure
Maybe they ran to avoid the start box
Define anthropocentricity
An inclination to evaluate reality in terms of human values
Define anthropomorphism
The attribution of human characteristics or behaviour to a god, animal or object
In 2000 what did Danbury et al do an experiment to find out?
If lameness hurt chickens
Define lameness
An abnormal gait or stance of an animal that is the result of dysfunction of locomotor systems
How did Danbury et al 2000 conduct their study?
First Danbury et al scored lameness severity in the chickens
Then they gave the chickens the option of normal food or food with analgesics
Then Danbury et al scored the chickens lameness severity after they ate the food
What are Danbury et al 2000’s experimental findings?
Non-lame chickens avoided the food containing analgesics, and when they did try the food with analgesics they would shake their heads
Chickens shake their heads when they eat something bitter or unpalatable
Lamer chickens ate more of the food containing analgesics suggesting that lame chickens ate unpalatable food to ease their pain
Danbury et al 2000 also noted that chickens that are the analgesics had better (lower) lameness scores
This suggests that lamness is due to pain and not just due to any structural issues in chickens
What happened in 2009?
An experiment was conducted to see when animals choose an environment if they are also the happiest they could be in that environment
How was the 2009 study conducted?
Over 36 weeks 60 hens lived sequentially in 3 different environments:
- Wire floor
- Shaving floor
- Enriched environment
It had perches and nest boxes
The 60 hens were grouped based on the random order they experienced the environments.
While living in each environment multiple welfare indicators were measured
After 36 weeks the hens choose repeatedly between different environments using a T-maze to compare the environments pair wise
What were the findings of the 2009 experiment?
The only significant difference was that chickens preferred the enriched environment over the wired floor environment
The chickens also seem to be mostly ‘logical’ in their choices
Their choices were based on the preference hierarchy in their head
The chickens did not choose randomly they actively thought and chose
The chickens also showed individual preferences for each environment
Some chickens preferred the wired environment over the others
The study found that prefer environments that were best for their welfare
In the 2009 study which chickens preferred the wire floor option?
Heavier chickens
How did the 2009 study conclude that hens prefer environments that were best for their welfare?
This was concluded due to the hens that chose their preferred environment had:
- lower body temperature
- lower blood glucose
- lower reactions to novelty
- greater feed digestibility
- more relaxed self-grooming
What are the 6 considerations for preference tests?
1) They only show relative preference
An example is A Vs B
These preferences are made in artificial environments which may alter decisions made
2) They show short term Vs long term preferences
These studies have shown that animals can actually get addicted to drugs
3) Maybe we are generating the motivation rather than measuring it
4) It’s hard to know what’s the best welfare indicator to use
5) Do animals choose what they really prefer?
6) Does giving them what they prefer improve welfare?
How are consumer demand tests different to preference tests?
Consumer demand tests are similar to preference tests but there’s a ‘cost’ associated with any particular resource
This cost allows us to quantify how much animals want that thing using a common currency
The common currency has to be relevant to the animal being studied
Are things that are important to animals but take a short time to happen equal to longer necessary things in consumer demand tests?
Yes, it just depends on study design
What was consumer demand tests based off of?
A simplified theory of economics
Economics looks at how people divide their limited money amongst the things that they want and need
In consumer demand tests when something is a necessity what is it known as?
Inelastic
This is because we will buy it regardless of cost
In consumer demand tests when something is considered a luxury we stop getting them when the cost increases. What are theses luxuries called?
Elastic
Who pioneered consumer demand tests?
Dawkins
What was Dawkins’ 1983 experiment?
How do caged hens value litter rather than wire floor?
What was Dawkins 1983 consumer demand tests ‘cost’?
Time
For chickens time is money
How was Dawkins 1983 consumer demand test conducted?
In the experiment the hens had access to either food or litter for either:
- 2 hours
- 4 hours
- 8 hours
The rest of the time the chickens were housed in cages with water only
If the chickens valued the litter highly, they would spend more time on the litter than on the wire with food even when time is restricted
What were Dawkins 1983 results of the consumer demand test?
Dawkins saw that as time became more restricted, hens spent a higher proportion of time eating
However there was no significant difference between their ‘free time’ spent on litter Vs wire
What did Dawkins 1983 argue was the causes of her consumer demand test results?
Food was too strong a trade off
The space was too small that chickens would explore even on the wire
Litter is not unimportant to chickens, the consumer demand test wasn’t designed good enough to test it properly
What are the 3 types of costs consumer demand tests can have?
Operant costs
Homeostatic challenges
Natural aversion/obstacles
Give examples of operant costs
Restricted time
Pushing weighted doors
Pressing levers
Give examples of homeostatic challenges
Energy restrictions
This is usually done with food
Body temperature
Give examples of natural aversion/obstacles
Wading through different depths of water
Climbing different barrier heights
Air blasts
Brightness
What are the 3 ways willingness to pay, or degree of welfare benefits, in consumer demand tests can be measured?
Elasticity of demand
Reservation price
Consumer surplus
In consumer demand tests what does ‘elasticity of demand’ mean?
This is where you measure the change in how much the animal accesses the resource in response to a change in cost
In consumer demand tests what does ‘reservation price’ mean?
This is where you measure the highest cost the animal is willing to pay for a resource
In consumer demand tests what does ‘consumer surplus’ mean?
This is where you measure the difference between the highest cost the animal is willing to pay verses the actual cost in real life
Reservation cost Vs real life cost
This can help provide cheap enrichments that are at the same importance as expensive ones
Name an example of a consumer demand test
Mason et al 2011
What was Mason et al’s consumer demand test looking at?
Frustrations of fur-farmed mink
How was Mason et al’s 2011 consumer demand test conducted?
In the experiment there were 8 males and 8 females
The animals were put in a central cage which was surrounded by further cages with either of the following in them:
Nesting site
Plastic tunnels
Toys
Novel objects
Wire tunnel and platform
Water pool for swimming
Empty cage to see if they wanted more space
Food
The mink would need to push through weighted cat-flaps to get to the resources
The weight was the cost
The weight of reaching the resources increased successively with each day
The weights varied between 0.00kg and 1.25kg with 0.25kg incriminates
Mason et al then measured duration and frequency of visits to each resource
Food was used as a baseline for maximum cost
Food is commonly used as a baseline for maximum cost
What did Mason et al 2011 find?
Access to the swimming pool was the most ‘inelastic’
Mink naturally live near water sources so this makes sense
Mink payed the most ‘cost’ to reach the pool across the board
What are the 6 things to consider in relation to consumer demand tests?
1) It’s important to choose a valid cost
2) Biological constraints and individual differences should be taken into consideration
3) Open and closed economy in terms of animals
4) Duration of testing
5) Suitability and substitutability
6) Is the artificial environments compelling the animal to do something since they’re already in a non-optimal environment
In consumer demand tests what is a open economy?
If the animal can access the resources outside of the experiment it’s an open economy
In consumer demand tests what is a closed economy
The animal can’t access the resources outside of the experiment
What kind of consumer demand test is considered to be the best?
Closed economy, long term experiments
This is not always the case though
In consumer demand test considerations what is meant by ‘Suitability and substitutability’?
This is when considering if a resource supplied meets more than 1 need or if it doesn’t allow all the behaviours you would expect the animal to do when exposed to it
When are conditioned place preference tests primarily used?
In pharmacology to test rewarding properties of a psychoactive drug
How are conditioned place preference tests conducted?
First the animal is dosed with the drug and placed into one compartment
Then the researcher waits for the drug to wear off
Then the researcher doses the animal with a placebo and places the animal in a distinctly different compartment
Then the researcher waits the same amount of time that it takes for the drug to wear off
This is then repeated until the animal can associate each compartment with a feeling based on the treatment they were on in that room
Then the animals, in an untreated state, are allowed to choose which compartment they want to be in
The animal will usually choose the compartments associated with the rewarding feeling attached to it in their minds
In a conditioned place preference test what is important to make sure about the compartments?
The different compartments are distinct from each other in regards to the animals perspective
How would you conduct a conditioned place aversion test
The method is the same as the conditioned place preference tests but the treatment used makes the animal averse to treatment compartment
This means you’d expect the animal to want to go to the placebo compartment when you let it choose the compartment it wants to be in
What are the 2 advantages of the conditioned place tests?
The conditioned place tests allow you to do a test for a resource’s importance when a preference test isn’t an option
Conditioned place tests avoid the animal approaching things just because they can see it instead of wanting it
It is known that during preference tests animals have been known to approach predators or competitors they would normally fight just because they can see them
How do conditioned place tests allow you to do a test for a resource importance when a preference test isn’t an option?
The compartments all have a resource, but they can be accessed whenever the animal wants to
This places all elastic and inelastic needs on an equal footing even if some take longer to accomplish
You will just see which compartment the animal prefers to go in, which it has associated with that resource when all compartments are empty
This gives researchers the option to study options that provoke differences in frequencies or durations of interaction can be compared
Name a conditioned place preference test?
De Jonge et al 2008
What was De Jonge et al 2008 testing?
De Jonge et al 2008 did a conditioned place preference test to see whether pigs preferred to either forage for treats or have them served in a trough
How did De Jonge et al 2008 conduct the conditioned place test?
First the 21 piglets were given a pre-test so they could explore each compartment to get to know what each one compartment had
In 1 compartment there was straw on the floor and 10 chocolate raisins in the trough
In the other compartment there was straw and 10 chocolate raisins hidden in the straw
Then during the conditioning phase each piglet was placed in each compartment for 3 minutes at a time, 10 times a day
After 7 days of conditioning the piglets were then allowed to enter the compartments freely when both compartments were empty
De Jonge et al 2008 then measured which compartments the piglets went into and the frequency and duration of each compartments visits
What were De Jonge et al 2008’s findings?
Piglets preferred foraging significantly more than the trough
Name a conditioned place aversion test
Elwood’s test on crabs
How did Elwood conduct their experiment?
Elwood provided the crabs with 2 dark shelters but would shock the crabs in 1 of the shelters
What were Elwood’s findings?
Crabs will generally return to shelters that they’ve previously occupied
However after receiving repeated shocks in 1 shelter the crabs were less likely to return to the shelter they were shocked in
What has research into crustaceans shown?
Elwood 2008: crustaceans avoid placed associated with electric shocks
Huber et al 2011: crustaceans approach places associated with morphine and amphetamines
What does professor Birch argue?
Professor Birch argued that findings by Elwood and other experiments show credible indicators of pain felt by crustaceans
However the evidence is not conclusive, but we should give the crustaceans the benefit of the doubt due to the potential suffering the evidence shows when cooking crustaceans
What are the 5 things you need to be aware of when conducting preference or consumer demand tests?
1) You need to remove or balance out environmental biases
2) You need meaningful alternative options
3) You need to consider if the experiment needs to cover a whole circadian cycle or even several seasons
4) You need to interpret the data with caution
5) You need to consider your measures/indicators carefully
Give an example of why you need to consider if the experiment needs to cover a whole circadian cycle or even several seasons to conduct good preference and consumer demand tests
Animals may not seem to care about nests unless it’s nighttime or they have babies
Why do you need to interpret the data with caution when conducting good preference and consumer demand tests?
Animals don’t always choose what is best for them
The artificial environment may affect their choices
Why do you need to consider your measures/indicators carefully when conducting good preference and consumer demand tests?
Sometimes animals spend lots of time investigating threatening stimuli, so other welfare indicators may reveal whether they like or dislike the stimulus
Approach does not always mean like
