Behaviour and Disease Flashcards
Detailed description, list or inventory of all the different kinds of behaviour or activity of a species is called…
An ethogram
How is behaviour used to aid in diagnosis?
Changes in behaviour, activity or posture brought on by disease can indicate
Many diseases initially present as behaviour changes
What must occur before diagnosing a primary behaviour problem and starting behavioural therapy?
Medical conditions must be ruled out
Example of behavioural response being mistaken as a disease?
Cat displaying urine marking behaviour, owner might think it has bladder infection, diabetes etc
How does behaviour affect disease transmission?
May increase or decrease it
Pathogen might be able to cause behavioural changes in host to increase transmission
Example of a pathogen that can change behaviour to increase its transmission
Rabies
Predators become aggressive/bite
Prey animals get dumb form, do not run from predators and infect them
Skin parasites (itch)
Example of pathogen that can “manipulate” host behaviour to increase disease transmission
Toxoplama gondii
Rodents lose fear which increases likelihood of them being eaten by primary host cat
Why might a pathogen be adapted to NOT change their hosts’ behaviour
Use normal behaviour to transmit disease because no change in behaviour, no signs/symptoms = do not know they’re infectious
What is needed to understand the behaviour that occurs in illness
Knowledge of disease mechanisms
Interdisciplinary co-operation
What is a motivational state, examples?
A state that overrides other states
e.g. hunger, reproduction, exploration, learning, hunting and SICKNESS
Which state often overwhelms or co-opts other motivational states
Sickness
What is the “proximate” of
disease
Causes of sickness behaviour (how)
What is the “ultimate” of sickness
Advantages of animal “acting sick”? Disadvantages? (why)
What are the two aspects of tinbergens questions related to proximate
Mechanism (causation)
Ontogeny (development)
What are the two aspects of tinbergens questions related to ultimate
Adaptive value (function)
Phylogeny (evolution)
What is the acute-phase response to cytokines
Fever, inappetance, increased sleep, postural changes, roduced motion, isolation
What is the acute-phase response to cytokines
Fever, inappetence, increased sleep, postural changes, reduced motion, isolation
Short term advantages of acting sick?
Energy saving, promote body defense mechanisms
Acute phase responses may have evolved as strategies for…
Addressing extreme threats to survival of a group, population or species
On the species level, how is disease dealt with?
Prevent transmission to conspecifics
Eliminate sick animal from population temporarily or permanently
Downside of acute phase responses
May be too late to reduce transmission
Might be unnecessary when we have veterinary therapy
- antimicrobials
- inflammation reducer
What does the expression of sickness behaviour depend on?
Context, environment
Which species (e.g.) present subtle behavioural indicators of sickness
Prey species
Horses, rabbits, rodents
When will prey species most often express sickness behaviour
In familiar environments around familiar conspecifics
How are welfare and disease related?
Disease will cause poor welfare, but poor welfare may also make disease more likely (immunosuppression)
How do adverse environmental conditions affect welfare
Alter animals susceptibility to infectious agents, results in poor health
How do animals respond to pathology (5)
Direct behavioural changes
Physiological changes
Production of cytokines
Immunological changes
Indirect behaviour changes
Definition of stress
Environmental effect on an individual that overtakes its control system and results in adverse consequences and eventually reduced fitness
Response to stress:
Brain activity
Adrenal/physiological response
Behaviour changes
Effect of stress on disease? Example?
Social stress impacts transmission
e.g. stress in weaned pigs may increase susceptibility to, and shedding of Salmonella occurring after unfamiliar pigs are mixed
What behaviour is observed for disease diagnosis
Posture
Gait
Acvitity
Vocalization
Mental state
Facial Expression
Piglet grimace scale observes what
Ear position, cheek tightening, orbital tightening
How do we use behaviour changes to diagnose disease
Daily routines change (eating, elimination, grooming)
Evoke behaviour (grunt while palpating abdomen)
To identify abnormal behavoiur caused by disease, we must first know
Normal behaviour (posture)
What diseases might affect posture
Mechanical conditions (injuries)
CNS
Pain
What is responsible for causing sickness behaviour
Proteins (cytokines) secreted by macrophages
What do cytokines do
Transmit messages from immune system to brain
