Physiological and behavioural responses to fear and discomfort in dogs and goats

• In this thesis, behavioural and physiological methods were combined to better understand reactions to fearful situations in dogs and separation in goats. Fear of gunshots is common in dogs, but also other fears, such as fear of walking on certain floors. The aim of the dog study was to establish whether it is possible to separate dogs that are fearful of floors and gunshots from dogs that do not fear these factors. This was done by studying behaviour and changes in heart rate, haematocrit, plasma cortisol, progesterone, testosterone, vasopressin and β-endorphin concentrations in thirteen dogs during a floor test and a gunshot test. Seven dogs that were fearful of floors had higher heart rate than six dogs that were fearless. However, seven dogs fearful of gunshots had higher heart rate, haematocrit and plasma concentrations of cortisol, progesterone, vasopressin and β-endorphin than six fearless dogs which demonstrates that fear of gunshots is a serious stress for the individual. The behavioural expression of fearfulness showed a large variation between individuals. The hypothesis of the goat study was that abrupt separation affects physiology and behaviour of the goats. For comparison, seven goats with their kids were first studied during suckling, a situation considered pleasant and peaceful. 3-4 days after parturition, goats and kids were separated. Suckling did not induce any cardiovascular changes in the goats. Plasma concentrations of cortisol and ß-endorphin increased, but oxytocin and vasopressin remained unaffected. Heart rate, arterial blood pressure and plasma concentrations of cortisol, β-endorphin, oxytocin and vasopressin did not change after separation. However, both goats and kids vocalised intensively. In conclusion, behavioural signs of fear and discomfort in animals are not always accompanied by corresponding changes in physiological variables. Combining both physiology and ethology is therefore desirable in evaluation of animal welfare.

Subject headings

LANTBRUKSVETENSKAPER  -- Veterinärmedicin -- Annan veterinärmedicin (hsv//swe)

AGRICULTURAL SCIENCES  -- Veterinary Science -- Other Veterinary Science (hsv//eng)

Publication and Content Type

vet (subject category)

lic (subject category)