Equine Lecture 4

Question 1

Level 1 of heat illness

Answer 1

Mentation is normal, very hot to touch and distressed. Slow recovery with increased rates of respiration, widely dilated nostrils, exaggerated thoracic excursions and an elevated heart rate. The horse is sweating profusely.

Question 2

Level 2 of heat illness

Answer 2

Mentation may appear normal but behaviour is irritable and uncooperative. Horses demonstrate unusual behaviour such as head shaking, and kicking out in a random fashion. May be subtle gait abnormalities

Question 3

Level 3 of heat illness

Answer 3

Obvious altered mentation showing signs of depression or disorientation. May have a glassy-eyed appearance. Increasingly difficult to handle, unpredictable, and dangerous behaviours. Ataxia and reluctance to move, followed by lunging forward

Question 4

Level 4 of heat illness

Answer 4

The horse demonstrates substantial levels of central nervous system dysfunction, unaware of its surroundings, throws itself down or falls down repeatedly, crashing into objects and ma rear over backwards. Clinical signs of endotoxaemia are characterised by hyperaemic mucous membranes and slow capillary refill times. These horses will progress the loss of consciousness convulsions, coma, and death unless treated rapidly and aggressively.

Question 5

What is thermoregulation

Answer 5

a process that allows a body to maintain its core internal temperature (homeostasis)

Question 6

What is homeostasis

Answer 6

dynamic process by which an organism maintains and controls its internal environment despite disturbances from external forces.

Question 7

What is radiation

Answer 7

movement of heat without physical contact
* Solar radiation from the sun
* Reflection from surrounding surfaces

Question 8

What is convection

Answer 8

movement of heat within a fluid
* Transfer between the surrounding air and skin surface * Forced convection through wind or fans
* Movement of heat within the bloodstream

Question 9

What is conduction

Answer 9

the direct transfer of heat between surfaces through physical contact
* Cold water
* Lying down on a cold surface

Question 10

What is evaporation

Answer 10

when molecules of a liquid gain enough kinetic energy to leave the surface of the liquid and become a vapour
* Sweating and panting
* Liquid surface is the surface on the coat
* 85% through sweating and 15% through the respiratory system

Question 11

Scraping

Answer 11

• Less than 40º -> does not matter
• More than 40º -> no
• Dry or humid -> no
• Cold -> yes