Stunning and Slaughter 2 Flashcards
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?
cheap
- 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
- electric
- 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
>schechita (jewish) - stricter rules - well trained - very sharp special knives >halal (muslim) - prayer (not necessary outlaid) -anyone can slaughter - need to standardise procedure >jhatka >ogun
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?
> upright
- 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)
Effect of post cut stun?
can remove brain function and minimise some suffering (aspiration blood, pain of neck cut etc.)
- high amplitude low frequency wave form (potensh other way round) indicates loss of sensibility
