Week 9: Indicators of emotional states

Horses in the natural environment include:

• 16-20 h/d grazing/foraging

• Live in social groups – reinforced by:

→Mutual grooming

→Food sharing

→The following behaviour

→Rest and play

• Feed on low-energy and high-fibreplants

• Travel over their home range (1-48 square km)

Horses fed under human management include:

• Often fed with high-energy concentrates and little forage - offered 2-3 times per day

• Limit social interactions - individually housed

• Restricting locomotion (inadequate physical exercise

Emotions are characterized based on their dimensions:

• Valence (positive and negative) – more common

• Arousal (high and low)

Emotion triggers behavioural and physiological responses

• Emotional indicators

• Validated - Sensitive - Specific

Physiological indicators of emotions in horses include

• HR

• Heart rate variability (HRV)

• Cortisol

Physiological indicators of emotions in horses: HR

• Sympathetic (increase HR): associated with arousal

• Parasympathetic (reduce HR): associated with rest

• Frequently used indicator of emotions in clinical practice and research; e.g. social restriction and fear

Physiological indicators of emotions in horses: Heart rate variability (HRV)

• Non-invasive a good indicator of psychophysiological stress and welfare

• Variations of inter-beat intervals

• Sympathetic-parasympathetic autonomic balance

• Better than HR

Physiological indicators of emotions in horses: Cortisol

• decreases after a certain period of time following a stressful event

• Blood, saliva, feces, hair

Examples of behavioural indicators of emotions in horses

• Facial expression, vocalization, eye blink rate, white eye

• Validated stress-related behaviours: oral, tail swishing, head high position, ear back

• The position of the ears and neck are the most common ones

• More robust and varied than physiological indicators

Acute and chronic emotional states in horses

Short-term indicators of emotions

Long-term indicators of emotions

• Learned helplessness

• Hair and Fecal cortisol

• Stereotypic behaviours; stress-reducing response

Stereotypic behaviours in horses

Repetitive behaviours with no obvious goal or function

• Crib biting

• Wood chewing

• Wind sucking

• Box walking

• Weaving

• Indicators of chronic stress (take time to develop) and poor welfare

• Two main categories: oral and locomotion stereotypies

Oral stereotypic behaviours in horses include

• crib biting

• wind sucking

• wood chewing

What can cause oral stereotypic behaviours in horses

GI irritation

Gastrointestinal irritation can be from:

• High-quality concentrates and a relatively low amount of forage

• Limited access to pasture

• Short feeding time and low meal frequency

• The stomach is empty – acid production – low PH – stomach ulcer

• No alkaline saliva to buffer the stomach acid

• Suggested as an adaptive response to stomach acidity

Locomotion stereotypic behaviours in horses include

• weaving

• box walking

What can cause locomotion stereotypic behaviours

Improper housing conditions

• social isolation

• restrictive locomotion

Recommendations to avoid stereotypic behaviours

• Increase feeding time

• Environmental enrichments - hay net

• Increase roughage

• Decrease concentrate

• Increase social contact - visual and tactile

• Facilitate pasture or paddock housing

3 Fs in horse husbandry

• forage

• friend

• freedom