5 Flashcards
Issues w/ using behavioural indicators to assess if poultry is stunned.
We are passing electricity through the entire bird - possible electro-immobilisation.
Tonic immobility - stress response in birds.
Indicators used for red meat do not work for poultry. e.g. no rhythmic breathing, no corneal reflex.
- a stunned bird can breathe, a stunned bird can have a corneal reflex.
Criteria for a stunned but live bird.
No breathing movements for >8 seconds from water-bath exit.
Wings held close to the body.
Rigidly extended legs and constant body tremors.
Breast muscle haemorrhaging - small fillet.
Supracoracoideus muscle.
Muscle that lifts the wing up.
Haemorrhaging at the head of the fillet where the tendon goes in as electrical stun causes muscle contraction so quick that it tears where the tendon is.
The more electricity applied, the more haemorrhage.
Breast muscle haemorrhaging - major fillet.
Pectoral.
Muscle that lowers the wing.
Only caused by electrical stunning.
More electricity, more damage, more haemorrhaging.
Legislation regarding controlled atmosphere stunning of poultry?
The poultry must be killed in the gas.
- stunning in gas takes 10-15 seconds so is not immediate.
The business operator and any person engaged in the stunning of poultry by exposure to gas must ensure that NO poultry are shackled before they are dead.
- death = no breathing, no corneal reflex.
High concentration CO2 gas.
Produces reaction from the bird.
Carbon dioxide in two phases (bi-phasic) description.
Successive exposure of conscious animals to a gas mixture containing up to 40% of CO2 (acidification of CSF around brain and spinal cord, causing analgesia and anaesthesia), followed, when animals have lost consciousness, by a higher concentration of CO2.
Conditions of use of bi-phasic CO2 stunning in poultry.
For poultry slaughter, depopulation and other situations.
- not permitted for pigs.
- slowly raising CO2 levels means working w/ the efficiency respiratory system of the chicken, that by the time the chicken is in a level of CO2 that it would notice, its body is already turning off.
– up to 40% to cause a loss of consciousness and above 40% to kill them while unconscious.
Bi-phasic CO2 gas stunning benefit to the product.
No electricity, no muscular contraction, no carcass damage, better quality product.
Bi-phasic CO2 gas stunning benefit to welfare?
No handling or shackling of the animal before killing.
Carbon dioxide associated w/ inert gases method description.
Direct progressive exposure of conscious animals to a gas mixture containing up to 40% CO2 associated w/ inert gases, leading to anoxia.
Method may be used in pits, bags, tunnels, containers or in buildings previously sealed.
Issue w/ carbon dioxide w/ inert gases mixture?
Flapping - damage and reduced carcass quality.
Effect of CO2 on the bird.
Effect of anoxia on the bird.
CO2 - no convulsions.
Anoxia - just affects brain so there will be spinal reflex activity when unconscious – anoxic convulsions which will produce wing damage.
‘Nature’ of Argon?
Heavier than air (same density as CO2).
Cannot taste it.
Cannot detect it.
Why is Argon and CO2 being heavier than air beneficial?
They can be put into a pit and contained there.
Animals can be gradually lowered in cages into the pit, where the concentration of CO2 or Argon is highest at the bottom (40%)
- the birds are seen to be unconscious by the time they reach the bottom at 40% concentration.
Monitoring and fail-safes of gas chambers.
Cameras inside to see.
Recording of gas concentrations at each level.
Alarms and stopping of the system if gas depletes to an insufficient level.
Personnel hanging birds afterwards have license to check the birds are dead before they hang them.
How is monitoring of dead-on-arrival animals carried out in gas stunning of poultry?
Still go through the system.
Then the post-kill hanging personnel identify birds in rigor mortis and take them off the production line.
Dead-on-arrival birds do not bleed properly, or pluck properly.
- so are darker red and still w/ some feather when inspected so are taken off production.
The advantages of gas killing.
Not shackled.
Not inverted.
No pre-stun shocks.
No problems w/ birds missing stunner.
No problems w/ birds receiving varied current.
Improved carcass quality.
Save money on labour.
- do not have to pay personnel for checking colour of breasts same within packs.
- do not have to pay personnel for trimming bad parts of the meat.
What does the term ‘slaughter’ refer to in the UK?
‘Causing the death of the animal by bleeding’.
Legislation for time from stun to kill of poultry.
As quickly as possible.
Legislation regarding method of killing in cases where poultry simple stunned?
2 carotid arteries or the vessels from which they arise shall be systematically severed.
- carotid arteries are white as they have so much pressure within them that they need a membrane around them to stop them from rupturing.
Halal vs non-Halal slaughter of birds.
Halal - knife.
Non-halal - knife or automatic neck cutter.
- licensed slaughterman must be present to ensure every bird is cut and bled.
In the case of simple stunning…
1. How long must you wait post-kill before any further dressing or electrical stimulation of the animal is performed for turkeys and geese?
2. “ “ For any other bird?
- Minimum of 2 minutes.
- Minimum of 90 seconds.
