Flashcards in Stunning and Slaughter 2 Deck (19):
stunning and slaughter methods of poultryz
- water bath stunning
- comb stunning
- captive bolt gun
- cervical neck dislocation
- players to crush neck
potential problems with water bath stunners
- water not head height for small birds (2 different sized shackles
- pre stun shocks
- sub maximal current flow to subsequent birds (first birds sufficient current)
Is waterbacth stunning reversible?
Not if low frequency
- unless high frequency levels then reversible
- need high current levels with high frequency to make it an effective stunning method
- high frequency stops convulsions so industry likes them but more opportunity to go wrong
Why is waterbath stunning used?
- gas stunning systems very expensive initial output
Where does the carotid sit in poultry neck?
Just ventral to vertebral column
- cut high up neck
- lower down neck more protected by spine
Why do you try and avoid removing head completely?
- cutting spinal cord removes signs of life, reflexes etc.
- industry likes this as stops convulsions
What to look at when inspecting birds at neck cutting?
- bird behaviour at bleeding
- blood vessels cut
- back up cutting
- death prior to scalding tank
How can you tell neck cutting machine not working?
red neck if get to scalding tank still alive
Common equipment faults
- broken transport crates
- inadequate facilities for cooling birds
- pre-stun shocks on entry ramp
- waterbacth electrodes not spanning length of bath
- voltmeter and ammeter displays inaccurate (new systems need data loggers built in)
- neck cutter severed spinal cord (masks recovery consciousness)
- neck cutter fails to sever the major blood vessels
Gas stunning/stun killing units
> pigs and poultry
- CO2 high concentration [ acidosis of the brain]
- CO2 two phase
- CO2 with inert gas (N and Ar) [cerebral hypoxia, expensive]
> vocalise a lot (may be unconscious)
- irritant and noxious gas
- feeling of breathlessness
> different concentration phases (esp for poultry)
- high concentration causes the aversive feelings
- at lower conc doesn't hurt mucosa -> loses consciousness but respiratory distress
> pigs high conc as poss
Farmed fish slaughter methods
- percussive blow
- suffocation air or ice (ice prolonged time to death, should also kill using another method aswell)
- food grade anaesthetic
- carbon dioxide
- cutting gills
What is puntilla? Legal?
> illegal Europe
- stab severing between first cervical vertebrae
- does not kill or stun animal
- paralysis immobilisation ONLY
- still sensible
Give 4 religious slaughter methods
- stricter rules
- well trained
- very sharp special knives
- prayer (not necessary outlaid)
-anyone can slaughter
- need to standardise procedure
Does method of slaughter affect blood loss?
- less blood loss with religious slaughter
- more blood lost with pre-stun slaughter
- no diference between electric and captive bolt
welfare issues of non-stun slaughter
- stress and pain of restraint
- pain cut
- distress associated with delays in time to loss of consioucness
- aspiration of blood and GUT contents
slaughter without stunning UK how must animals be restrained?
- EU can use rotating restraint
- evidence shows these more distressing (aspiration gut contents, pressure heart and lungs)
> upright need hydraulics - may also impact welfare
How long does it take to lose consciousness after ventral neck incision?
> cattle longest but also most variable
- vertebral artery supplies brain
- carotid shrinkage and blockage stops further blood loss
> cut high in neck lose consciousness faster than low neck
Is pain experienced with a neck cut without stunning?
Yes gibson 2009 shown (up to 30s after)