Horse 5- Retirement and euth

Question 1

Horse changing careers

Answer 1

Horses are often not used at high level for entire life. Exception is dressage horses.

Common horses that switch:
1. most commonly off the track thoroughbreds will make a career change and can switch to basically anything
*high earners will be used as breeding stock

2. Working ranch horses
   -will switch to other western disciplines

Question 2

Switching Off the track thoroughbreds

Answer 2

Trained to run in a circle to the left so need complete retraining when career ends

Possible career paths: hunter, jumpers, dressage, barrel racing, ranch work, pony club, polo

Question 3

How are off the track throughbreds acquired after retirement?

Answer 3

-direct racing connection
-resale
-non-profit aftercare facility
-auction/kill pen

Question 4

Why do horses need a career switch?

Answer 4

Need a reduced workload, may be due to age, illness or injury

Question 5

Options for animals that need a reduced workload?

Answer 5

Depends. Definitive diagnosis will help determine best decision

-retirement
-lower level of work/performance
-sell (with provisions- background information often not given) **bet if you could do a pre-purchase exam
-donate (eg. teaching horses)

Question 6

Retirement plans/options

Answer 6

-kid horse
-companion animals (for a person or another horse)
-equine therapy (eg. Bomb proof)
-retirement or rescue farms

Question 7

Euthanasia

Answer 7

-must cause immediate unconciousness… can use general anesthesia

-reflex movements may occur (agonal breathing, nystagmus, paddling, muscle fasiculations)

-death may take several mins

Question 8

Signs of consciousness

Answer 8

-vocalization
-attempts to rise
-lifting head
-blinking
-response to painful stimulus

Question 9

Why euthanasia?

Answer 9

**circumstances= can be planned or emergency

-injury
-sick
-old (especially in winter)
-economics/expense of need of surgery
-lack of feed in fall (dig a hole before ground freezes)
-behaviour/safety
-can no longer perform/complete their job

Question 10

Criteria/reason for euthanasia

Answer 10

1. Pain and suffering
2. likelihood of survival
3. cost of treatment
4. return to use/performance
5. length of recovery
   6.insurance status

Question 11

What to discuss as a vet for horse euthanasia?

Answer 11

-is horse likely to recover? QOL?
-how long will it take for horse to recover?
-how long is owner willing to provide increased care to horse?
-what is QOL currently?
-is owner able to provide the increased level of care?
-has the horse gotten better or worse during treatment?

Question 12

Criteria for euthanasia

Answer 12

-quick
-minimal pain/stress
-cause immediate unconsciousness

Question 13

Methods of euthanasia

Answer 13

-lethal injection (overdose of pentobarbitol, KCl, MgCl, MgSO4)
**pentobarbitol is toxic to scavengers
-intrathecal lidocaine injection
-captive bolt (penetrating or followed by pithing)
-gunshot

Question 14

Things to consider at euthanasia appointment

Answer 14

-circumstances
-does client want to be present of absent
-surroundings
-method of disposal
-be aware of other pets, wildlife, scavengers

Question 15

Drug administration

Answer 15

-Place catheter
*euthanasia drugs can reduce blood pressure and make it hard to get into the vein afterwards

-drugs: sedation and general anesthesia

Question 16

Notes about cold weather

Answer 16

-drugs and equipment can freeze

Question 17

Pentobarbitol mechanism

Answer 17

Binds GABA receptors and causes CNS depression
-inhibits glutamate resulting in nerve depolarization in voltage Ca channels

Results in loss of respiration, then brain dead in 73-261 sec, heartbeat stops, brainstem reflexes stop, ECG activity last to go

Question 18

Use of pentobarbitol in horses

Answer 18

-catheter and 2 long extension sets
-sedate
-stand back
-rapid injection
-unpredictable reflexes
-agonal breaths

70-150mg/kg dose

**might be slower in cardiovascular compromised horses because takes longer to get to destination

Question 19

Use of KCl and Mg salts for euthanasia

Answer 19

-anesthetize prior to injection… cannot be used in conscious animal

-power dissolved in warm water and giver rapid IV

-not toxic to environment

KCl= cardiotoxic and colonic spasms (75-150mg/kg)

MgCl, MgSO4= suppression of neural activity (2ml/kg)

Question 20

Use of intrathecal lidocaine

Answer 20

2% lidocaine hydrochloride given at atlanto-occipital space under GA
-stops brainstem function immediately (stops breathing)
-loss of brain activity in 226secs, heart beat stops in 10mins

cheap, readily available, non toxic

Question 21

How to administer intrathecal lidocaine?

Answer 21

1.anesthetize horse
2.AO tap with 18g spinal needle (will hear pop and CSF will come out)
3. remove 30-60ml of CSF prior to reduce pressure and making injection easier
4. Administer 30-90ml 2% lidocaine

Question 22

Gunshot or captive bolt

Answer 22

Higher than in a cow
-just above the point of intersection of the lines drawn from medial canthus of eye to middle of the opposite ear

Question 23

Alternative methods of euthanasia

Answer 23

-laceration to the aorta via rectal palpation
-difficult and dangerous! Only perform if horse is already down

Question 24

Confirmation of death

Answer 24

Must be confirmed!
-absence of movement, auscultable heartbeat and pulse, absence of respiration, fixed and dilated pupil, lack of corneal blink reflex

Question 25

Disposal of horse

Answer 25

-burial (must be 6ft), landfill, rendering, cremation, chemical digestion

*remember pentobarbitol is toxic and may not be accepted at rendering

*towing companies will often move carcasses