Slaughter and Carcass Dressing

Question 1

Describe the process of cattle slaughter

Answer 1

Question 2

Describe the process of lamb slaughter

Answer 2

Question 3

Describe the process of pork slaughter

Answer 3

Question 4

What is the regulation regarding the protection of animals at the time of killing?

Answer 4

Council Regulation (EC) No 1099/2009

Question 5

What is the definition of stunning?

Answer 5

Any intentionally induced process which causes loss of consciousness and sensibility without pain, including any process resulting in instantaneous death

Question 6

What are the aims of stunning?

Answer 6

Kill/Slaughter humanely
Obtain the maximum amount of blood from the animal (increases keeping quality)
Health and safety

Question 7

What do all members of staff working in an abattoir require?

Answer 7

Certificate of Competence (CoC)

Question 8

What are the methods of stunning used in abattoirs and which animals are they used on

Answer 8

Captive bolt - ruminants (simple stun)
Electronarcosis - pigs, sheep and poultry (stun to kill in cows)
Gas - pigs and poultry (stun to kill)

Question 9

What are the physiological effects of captive bolts

Answer 9

Heavy blow => acceleration of head => brain impact (physical damage)
Damage to nerves and blood vessels
Massive rise and fall in pressure
Disruption of normal electrical activity
Duration depends on severity of damage

Question 10

What are the signs of an effective stun?

Answer 10

Collapse
No rhythmic breathing
fixed glazed expression
no corneal reflex
relaxed jaw
tongue hanging out

Question 11

What are the phases of captive bolt stunning?

Answer 11

Tonic phase (10-20s)
- collapse
- stops breathing
- becomes rigid
- head extends/hind legs flexed
- forelegs straighten
Clonic phase
- involuntary kicking
Relaxation
- walking/paddling

Question 12

What are the minimum currents required to electrically stun animals?

Answer 12

Question 13

What are the phases of electrical stunning?

Answer 13

Induces an epileptic fit
Tonic phase:
- rigid
- breathing stops
- head raises
- hind legs flexed
Clonic phase:
- gradual relaxation
- paddling
- downward rotation of eyes
- foaming/urination
Recovery

Question 14

When should sticking/bleeding be done after stunning?

Answer 14

before clonic phase ends (no more than 15s)

Question 15

What are the different methods of gas stunning?

Answer 15

CO2 at high conc
CO2 + inert gases
Inert gases

Question 16

Describe the process of gassing to stun via high CO2 conc

Answer 16

Minimum 80% CO2 conc
Exposure must lead to anoxia (loss of oxygen to brain)
Pig must be conveyed to max conc of gas withing 30s

Question 17

Describe the use of CO2 mixed with inert gases for stunning

Answer 17

40% CO2 conc mixed with inert gases

Question 18

What inert gases are used for stunning pigs?

Answer 18

argon or nitrogen

Question 19

What are the signs of effective stunning by gas?

Answer 19

Recumbent animal - limbs, jaw relaxed
No voluntary movements or righting reflexes
No response to pin prick on nose
Absence of normal breathing

Question 20

What are the advantages of gas stunning

Answer 20

No excitement
Completely relaxed => easy bleeding
Non-invasive
Reduced blood splash
Reduced pale soft exudative (PSE) => higher meat quality

Question 21

What are the disadvantages of gas stunning?

Answer 21

Expensive
Welfare doubts:
- acidic gas pungent to inhale
- potent respiratory stimulant => breathlessness
- not instantaneous

Question 22

What are methods of bleeding post stunning and which animals are they used on?

Answer 22

Neck cut (carotids and jugulars) = small ruminants
Thoracic stick (ascending aorta) = cattle and pigs

Question 23

What are the factors affecting bleeding?

Answer 23

health of animals
Rest prior to slaughter (muscle tone)
Back bleeding into thoracic cavity
Blood splashing (capillary rupture)

Question 24

Describe the features of blood splashing (capillary rupture)

Answer 24

Related to increase in blood pressure
More common in electrical stunning
Stress, diet, physiological or genetic factors
Shows as black spots on offal

Question 25

What is the purpose of polishing pig carcasses?

Answer 25

improves quality
eliminates burned hair and superficial epidermis

Question 26

What are the disadvantages of polishing pig carcasses?

Answer 26

Excessive force could produce some minor damage in carcass
Increases contamination

Question 27

What are the official controls for exports of Products of Animal Origin (POAOs)

Answer 27

All POAOs exported from UK must be accompanied by an official EHC (export health certificate) signed by a vet
Documents are checked
Notifiable disease clearance
Physical checks of product