Animals as Food Part 1: The abattoir Flashcards
What is the definition of a slaughter house?
An establishment for the slaughtering and dressing animals, the meat of which is intended for human consumption
What species are legally allowed to be processed in the UK?
- Red meat (cattle, sheep, pigs, goats, solipeds)
- Pultry
- Lagomorphs
- Wild game
- Farmed game
How would you describe a good lairage?
- equipped with water and feeding facilities
- regards for animal welfare
- adequate drainage
- adequate lighting
- easy to clean and disinfect
Who performs an ante-mortem inspection?
performed by an official veterinarian
When does the ante-mortem inspection happen?
24 hours of arrival to the premises and within 24 hours before the time of slaughter
What is the purpose of an ante-mortem inspection
To identify
* animals that deviate from normal behaviour
* heavily contaminated animals
* animals which are suspected of having a reportable or exotic diseases
* that animals are correctly identified
What are the slaughter outcomes after Ante Mortem Inspection?
- proceed to normal slaughter
- animal is deemed a suspect and set aside for separate slaughter
- animal is deemed a suspect and proceeds for immediate slaughter
- animal is condemned and euthanised
Who issues the certificate of competence?
The Food Standards agency
What cant you do without a certificate of competence?
- handle live animals before they’re restrained
- Moving animals in lairage
- Restrain animals for stunning or killing
- shackle or hoisting live animals
- stun animals and checking stunning has worked
- bleed live animals
- religious slaughter
- pithing of a stunned animal and checking pithing has worked
What does stunning mean?
- any intentionally induced process which causes loss of consciousness and sensibility without pain
can only be performed with a certificate of competence
What are the three phases of stunning?
- Tonic
- Clonic
- Recovery
What is in the tonic phase of stunning?
- Animal collapses and becomes rigid
- Stops breathing
- Rigid: head extended and hind legs retracted
lasts around 10-20 seconds
What is in the clonic phase of stunning?
- Flexed legs gradually straighten out
- Involuntary kicking, paddling
- No rhythmic breathing movements
What is in the recovery phase of stunning?
- Normal rhythmic breathing
- Response to pain
- Visually aware
- Attempts to stand
What are the three methods of stunning?
- Mechanical
- Electrical
- Gas Mixture
What are the two types of mechanical stunning?
Penetrative and Non-Penetrative
How would you administer immediate insensibility via mechanical stunning?
a severe blow to the skull of the brain
What does the blow to the skull of the brain do?
- Disruption of brain electrical activity
- Damage to nerves and blood vessels
- Physical damage to skull or brain (penetrative / non-penetrative)
How does a captive bolt gun work?
- Steel bolt held in a barrel
- explosion of charge
- bolt moves forwards and backwards
What are the phases of effective stunning?
- Animal collapses
- No Rhythmic breathing
- Fixed, glased expression
- no corneal reflex
- relaxed jaw with tongue hanging out
What is electronarcosis?
passing electrical current through the brain to
disrupt normal activity. Immediate unconsciousness but it is reversible
What are the two ways you can die after electronarcosis?
- Bleeding- severing major blood arteries
- Electrocution- electric current to stop the heart
What does electronarcosis induce?
Induces an epileptic fit
* brain severely stimulated,
* body tonic/clonic activity,
* Complete loss of consciousness
How does electrocution kill animals?
Killing by stopping the heart from pumping blood around body
(cardiac arrest)
»Heart enters ventricular fibrillation estate: heart muscle fibres
contract rapidly, uncoordinated and blood supply stops
»No oxygen to the brain
»Painful so animal should be stunned first
What are the four signs of electrocution?
»Animal becomes rigid
»Body tremors and gradually relaxes until no further movement
»No eye movement
»No corneal reflex
What are the signs of electrocution?
Animal becomes rigid
»Body tremors and gradually relaxes until no further movement
»No eye movement
»No corneal reflex
How does gas stunning work?
Stunning of animals by exposure to a gas mixture (low levels of
oxygen).
»Induce brain anoxia and ultimately death of the animal.
»Animals rendered unconscious and insensible without discomfort.
(CO2 has a direct anaesthetic effect)
What are the advantages of gas killing?
- Reduced risk of human error
- Animals remain in groups
- Consistency and effectiveness at high throughputs
What is disadvantages of gas killing?
- Carbon dioxide is aversive to animals
- Exposure to high concentrations compromises welfare
- Cost, complexity and increased chance of system breakdown
What are the signs of a correct gas stunning?
- Limp body
- No corneal reflex
- Dilated pupils
- Jaw relaxed and tongue hanging out
- No breathing
What percentage of an animals optimal weight should the blood be?
6-7% of the live weight
What are the signs of poor bleeding?
- Serous membrane and lymph nodes dark red colour
- Congestion of offal
What is the spear-cut technique for skinning cattle?
blade of the knife reversed so cut from the inside of the
skin towards outside
What are the main areas for skinning contamination?
»Chest / abdominal region
»Forequarter region
»Hindquarter region
»Around anus
What occurs in pigs rather than skinning
depilation (scalding, de-hairing and singed)
What is evisceration?
removal of stomach, intestines and organs removed from the carcass
What are the three sealing techniques for evisceration?
- Bunging (sealing the rectum)
- Rodding (elastrator ring applied at the oesophageal-rumen junction)
- Tying a knot (only in lambs and pigs)
What is the principle of post-mortem inspection?
To supplement ante-mortem inspection and to detect
* diseases of public health significance
* diseases of animal health significance
* residues or contaminants in excess of the allowed levels
* visible lesions that are relevant to animal welfare
What are the key principles of Post-Mortem Inspection?
- OV assisted by Meat Hygiene Inspectors
- Visual inspection, palpation, incision
- avoid meat contamination
- particular attention on zoonoses and notifiable diseases
- keep correlation of the carcasses and offal at all times
What would you consider to be a ‘poorly-designed’ slaughterhouse?
- Inapropriate site
- Poor layout
- Inapropriate construction materials
- Insufficient space
- lack of adequate hygeine facilities
What facilities would you find at a slaughterhouse?
- Lairage
- stunning, slaughter/ bleeding and dressing areas
- rooms for refrigerated storage of meat
- lockable chillers
- separate areas for manure/ digestive content
What are 7 potential sources of contamination?
- Hides and hair
- Soil
- Contents of the stomach and gut
- Water
- Vermin
- Airborne pollution
- Tools and equipment
What are some methods of reducing contamination?
- Cleanliness of animals presented for slaughter
- Protective clothing
- Training operatives on hygienic techniques
- Water/ Pest control programme
What are the names of the buffers in a captive stun gun?
Recuperator sleeves
When should animals be handled and/or kept separately in the lairage?
if they are-
* different species
* significantly different ages
* adult breeding boars or stallions
* animals with horns
* animals that are hostile to each other
What is the function of the recuperator sleeves?
acts as a buffer
What may happen if the animal is in the incorrect positioning for stun?
- ineffective stun
- causes pain and distress
How may an animal die via bleeding?
- Death by acute anaemia
- bleeding is profuse and complete
What is the sticking to dressing time for cattle and other species respectively?
- 30 seconds in cattle
- 20 seconds in other species
What are some factors that effect optimal bleeding?
- emergency slaughter
- Stress
- Animal health status
- stunning/ sticking techniques
What is the function of a hide-puller machine?
completely removes the hide from the carcase
What can potentially contaminate the carcase during skinning?
Hair, Soil, Debris
How would you skin a sheep?
There are similiar hygeine considerations as with cattle
* suspend initially via the forelegs
* loosen the pelt around the shoulders
* partially free the pelt from the hindquarters
* remove the pelt using a mechanical pelter
* suspend by the hindlegs
What are the two ways you can use depilation on pigs?
- Scalding tank (60-65, 7-10 minutes)
- Vertical scalding with humidified air
What are the general hygiene requirements for the food premises?
Food premises need to be kept clean and maintained in good repair
What is the general function of the layout, construction and size of the food premises?
in terms of cleanliness
- provide adequate working space
- minimise air-borne contamination
- protect against accumulation of
1. dirt
2. shedding of particles
3. formation of condensation
4. mould on surfaces
5. pests
What are some special considerations for the cleaning areas in a slaughterhouse?
- dressing rooms
- red offal preparation and packaging
- carcase chill
- despatch
What are some special considerations for the detained meat facilities?
Needs to be chilled
lockable
and have a dedicated room or cage within the chill
How can you ensure cleanliness of farm animals in terms of diet and animal health?
- Diets on high dry matter content
- gradual diet change (prevent scouring)
- animal health plans to reduce enteric pathogens
- husbandry and therapy to prevent parasite infection
How can you ensure farm animal cleanliness in terms of housing?
- adequate ventilation
- clean and dry straw bedding
- appropriate stocking densities
- design of the feeding and drinking facilities
How can you ensure farm animal cleanliness in terms of transport?
- vehicles need to be cleaned before transport
- adequate ventilation
- protection against adverse conditions
- appropriate group sizes of uniform animals
How can you ensure farm animal cleanliness in terms of the abattoir?
Dirty animals compromise hygiene of operations
»Reject dirty and wet animals for slaughter / Delay slaughter until dry
»Washing animals have detrimental effect on bacterial load and may
compromise welfare
»Clipping to remove dirty hair / wool
»Processing at the end of the day with decreased line speed
What is the two knife technique for sticking?
- You use one knife to cut the skin
- And a second knife to cut blood vessels
How can you help prevent cross-contamination in an abattoir?
- Make sure the offal does not contact walls
- if contact is unavoidable-
- materials are to be rinsed and sterilised with water at 82 degrees between carcasses
- meat is protected with plastic sheets and bags
What are some chemical treatments you can use in post-slaughter decontamination?
- chlorine
- Organic acids
- Hydrogen peroxide
- Antimicrobials
- Phosphates
What is the traditional washing of carcasses and why shouldn’t you do it?
At 12C/53 F
* spreads bacterial load to ‘clean’ areas of the carcase
* remaining water provides ideal conditions for bacteria multiplication
What does trimming rely on?
Only approved method in UK/EU for all red meat species
it is the most practical and effective method for reducing microbial contamination
* frequent sterilisation of knives and tools
operative technique*
