VPH Flashcards
What does the FBO have to do if food chain information for a batch of poultry shows a positive test for salmonella enteritidis or typhimurium?
FBO must retain the affected batches and slaughter them at the end of the production day, after slaughter undertake a full cleansing and disinfection of equipment and machinery, including changing the water in the scalding tanks, and renewing the water in the spin chillers. Where a positive batch has been processed in the middle or at the end of a production run then the production run should be stopped as soon as the affected batch has been processed and a full clean down as above take place before any further processing commences. Following production, in the absence of any relevant AM or PM findings, teh carcases can enter the food chain as normal.
What is the purpose of AMI in poultry?
Accurate AMI should include listening to the birds and observation of a random sample checking posture, wattle colour and clealiness. If the birds show clinical signs of a disease, they may not be slaughtered for human consumption. Killing of these birds on the slaughter line may take place at the end of the normal slaughter process if precautions are taken to avoid the risk of spread of pathogenic organisms and to clean and disinfect the facilities after killing.
Which poultry diseases can be checked for at post mortem infection?
Pasteurellosis, salmonellosis, avian chlamydiosis, avian mycoplasmosis, avian TB, erysipelas, infectious coryza, avian influenza, infecitous bronchitis, infectious bursal disease, infectious laryngotracheitis, newcastle disease, viral arthritis, mareks disease.
How should poultry be unloaded at the abbatoir?
Must be protected from adverse weather conditions, must be provided with adeqate ventilation, must be unloaded form behicles as soon as possible after arrival, avoiding unnecessary delay. FBO must check welfare of animals. Crates containing birds must be unloaded from vehicles with care in a calm unhurried manner. The crates should be maintained in the upright position so that the birds are not in an unsettled or excitable state when they are subsequently handled before slaughter. Crates are stacked far enough apart to permit adequate airflow between stacks.
How long should birds be shackled for?
give Shackled birds time to become settled in the hanging position (12 secs for chickens and 25 secs for turkeys). It is inappropriate to shackle sick or injured birds. Birds must not be shackled for more than 3 minutes in the case of turkeys or 2 minutes in the case of any other bird. Birds should be hung on by both legs and well fitted into shackles.
How can an effective simple stun be recognised?
No rythmic breathing for 10-20 sec after leaving the water bath, neck arched with head directed vertically, dilated pupils, absence of a corneal or 3rd eyelid response, no response to comb pinch, wings held close to body, rigidly extended legs, constant body tremors.
How can an effective stun kill be recognised?
If the bird has received an effective stun kill and is dead the following signs will be seen: fixed central dilated pupils, no rythmic breathing, no response to any stimuli, limp carcase.
What are the advantages to gas stunning birds?
Shackling and inversion of live birds is avoided, no need for birds to be handled, no pre stun shocks, all birds are dead prior to bleeding, fewer broken bones, less damage occurs in breast meat.
What are the disadvantages of gas stunning birds?
More expensive to run than electrical stunner, still need a back up system in place incase of break down, health and safety for people in case of gas leak, higher level of training needed for slaughtermen.
How long should the stun to bleed interval be in poultry?
less than 15 seconds is recommended. the cut must sever at least one of the carotid arteries or the vessels from which they arise. More rapid bleed out is achieved if both carotid arteries are cut.
What temperature should scalding be?
51-53C for 3 min
What temperature should carcasses be kept at?
Poultry meat not stiffened by the cooling process which is to be kept at a temperature not below -2C and not higher than 4C at any time.
What ID must a horse have to be slaughtered for human consumption?
any equidae slaughtered for human consumption must be accompanied by a valiv passport which does not show that the animal is NOt intended for slaughter for human consumption -
Sextion IX part II is NOT SIGNED.
there are no other stamps are markings within the human passport which indicate that the horse is not intended for human consumption.
There is no vet treatment which would make it unsuitable for human consumption e.g phenylbutazone.
Foals born after july 2009 must also be mandatorily implanted with a microchip. These may enter the food chain if seciton IX is not signed.
What is campylobacter and what symptoms does it cause in humans?
A gram negative curved vacillus.
Incubation period is 2-5 days. symptoms include fever, headache, myalgia initially then diarrhoea, dysentry and abdominal pain. The usually course is
What are the risk factors for acquiring campylobacter infection?
Consumption and handling of raw or undercooked meats, especially poultry, cross contamination of food during preparation, consumption of raw milk, consumption of surface water or well water, direct contact with animals, underlying disease.
How does campylobacter affect poultry?
It is considered a commensal in the intestinal tract, especially the caeca of birds, which causes an induced mild inflammatory response in birds intestines but this does not clear bacteria. It is non pathogenic in birds. 75% of broiler chicken batches on farms in uk were campyobacter positive in 2008.
What is salmonella? What symptoms does this have in humans?
A rod shaped, motile gram negative bacteria. Nausea, vomiting, abdominal carmps, diarrhoea, fever and headache.
What is the delvo test? what is it sensitive to?
Cultures of Bacillus stearothermophilus var. calidolactis in solid agar medium and indicator A standard diffusion test for detection of antibiotic- and/ or sulfa residues in milk – An Ampule Test – A Plate Test -Sensitive to most of antibiotics- detection limit for penicillin 0.003IU per ml - Simple and quick
How else can milk be tested for antibiotic residues apart from the delvo test?
The New SNAP BetaLactam Test is an enzyme receptor binding assay • Dectects penicillin G, amoxycillin, ampicillin, ceftiofour and cephapirin residues in raw milk at below or below tolerance and /or safe levels
What is the difference between a best before and a use by date?
Use-by date: last date by which product should be
consumed; product may not be safe to eat after this date
due to growth of pathogens and potential for food
poisoning; applies to foods which are highly
microbiologically perishable
• Best-before date: refers to quality of the food; taste,
texture, aroma etc. of the food will be best before this date
as long as storage instructions are followed but can be
eaten after this date
What is the difference between UHT and pasteurisation?
UHT: 135o C for 1-4 seconds; kills all micro-organisms and spores;
sterile product
• Pasteurisation: various protocols; most common 72o
for 15 seconds;
reduces number of viable pathogens and also destroys many
spoilage organisms; spores and thermoduric bacteria survive
• UHT is safer than pasteurised milk as it destroys all micro-organisms
whereas pasteurisation results in a 5-log reduction in pathogen
numbers but spores can survive and potentially lead to foodpoisoning
e.g. Bacillus cereus
What are the public health concerns with eating tuna?
Clostridium botulinum intoxication (botulism)
• spore survival at canning temperatures with subsequent toxin
production;
• ingestion of toxin in canned food;
• paralytic illness; starts at face and spreads; can be fatal is respiratory
involvement;
• commercial canning includes ‘botulinum cook’ step (121o C for 3 mins)
to destroy toxin but occasional cases still occur; home canning more
NB
– Histamine toxicity:
• Histidine found in many fish types
• Converted to histamine by several enteric bacteria on exposure to air
at room temperatures
• Histamine is not destroyed by cooking;
• Histamine is mediator of allergic reaction therefore signs are those of
allergic reaction; occur rapidly after ingestion and usually self-limiting
What are the risks concerned with eating canned food?
Lead poisoning – migration from lead seal on can; not
commonly used
o Bisphenol A toxicity – used to make epoxy resin lining can;
acts as xenooestrogen; may have numerous side effects
Why is a white coating of lacquer necesary on some canned foods?
– Lacquer
– Prevent contact between metal and food
– Necessary for acidic & high protein foods
What testing must be done in the UK for pigs for trichinella?
In trichinella free zones like the UK - it is not required to do tests for domestic pigs kept solely for fattening, or meat from domestic pigs subject to freezing treatment under official controls. We have to test: Breeding pigs (sows or boars) Wild or farmed boar Solipeds (horses)
Name the body part to be sampled for trichinella in the following species;
Wild boar
Breeding sows/boars
Horses
Breeding sows/boars- Pillar of the diaphragm at the transition to the sinewy part.
Horses 10 g lingual or jaw muscle
wild boar - Foreleg, tongue or
diaphragm
What is the cold storage requirement for carcasses affected with C bovis?
Not exceeding -10 for not less than 2 weeks
not exceeding -7 for no less than 3 weeks
When can meat be exempt from trichinella testing?
Meat from domestic swine that has undergone a freezing treatment under the supervision of the competent authority shall be exempt from trichinella examination. Meat must be of a diameter or thickness of up to 15cm, must be frozen for one of the following time temperature combinations - 20days at -15C, 10 days at -23C, 6 days at -29C.
What type of tumour is OPA?
A bronchioalveolar adenocarcinoma of type II pneumocytes.
What are hydatid cysts?
They are the intermediate stage of echinococcus granulosus, a tapeworm of dogs. the cysts are found in the liver and lungs. each cyst has a thickened, laminated outer membrane and is filled with clear fluid. hundreds of protoxcolex develop from the cysts inner lining.
What is lipfuscinosis?
A harmless brown/black pigment which accumultaes in kidney or heart muscle, it causes smooth, brown, mahogany or black coloured kidneys.
Which carcases should be declared ‘unfit’ for human consumption?
animals that have not undergone AMI (except for wild game)
Animals the offal of which has not undergone PM,
animals which are dead before slaughter, stillborn, unborn or slaughtered under the age of 7 days,
meat from the trimming of sticking points,
animals affected by a generalised disease such as septicaemia, pyaemia, toxaemia or viraemia, meat that exhibits parasitic infestation, contains residues or contaminants, contains forbidden substances, derives from emaciated animals, contains foreign bodies, except in the case of wild game, indicates physiological changes in consistency with insufficient bleeding or organoleptic anomalies eg a pronounced sexual odour.
What is E coli? What are the symptoms of EHEC infection in humans?
A gram negative, facultative anaerobic bacillus found in lower intestinal tract of mammals and birds. ETEC, EPEC, EHEC all cause intestinal disease. EHEC is sometimes referred to as STEC (shiga toxinigenic). symptoms may range form mild diarrhoea to haemorrhagic colitis. ruminants especially cattle, appear to be the primary resevoir with asymptomatic carriage.
What is listeria monocytogenes? how do humans become infected with this? what are the symptoms?
A gram positive facultative anaerobic bacillus. It is capable of growth over a wide temperature range including refrigeration temperature. It causes acute febrile gastroenteritis - fever, nausea, vomiting, diarrhoea, and lasts 7-10 days. Incidence of listeriosis is relatively low but it has a high case fatality rate. Listeria can be found in a wide variety of foods, both animal origin and non animal origin. Contamination can occur at any point along the fod production chain. It survives in environment of food business. clinical cases of disease usually associated with ready to eat foods e.g coleslaw.
What is the most common food spoilage organism?
Pseudomonas - particularly in foods with high water availability, near neutral ph and stored in aerobic atmosphere such as meat, fish and dairy products. Other non enteric gram negative bacteria such as aeromonas, acinetobacter, alcaligenes, flavobaterium are alsopsychotrophic and capable of tapid multiplication at chill temperatures. Gram neg bacteria grow in the absence of oxygen.
which animals can be sent to the abattoir as emergency slaughteR?
An otherwise healthy animal that has suffered an accident that prevented its transport for welfare reasons. Factious animals that are too wild to handle, water buffalo and bison as their anatomy prevents approved stunning methods. ANY BOVINE OVER 48 MONTHS OF AGE THAT MUST BE SENT AS EMERGENCY SLAUGHTER - REQUIRES ITS BRAIN STEM TO BE SAMPLED IN ORDER TO BE TESTED FOR BSE.
Which animals can not be sent to the slaughterhouse as emergency slaughter?
Animals suffering from a chronic condition, animals that following veterinary exam are unfit for human consumption e.g systemic disease, cachexia etc, animals with drug withdrawal periods not respected, cattle born in the UK before 1st august 1996. Pithing is not allowed for animals going for human consumption.
What is the recommended bleeding time (time from sticking to scalding) for electrically stunned broilers?
At least 90 seconds.
A stun to bleed interval of less than 15 seconds is recommended. The cut must sever at least one of the carotid arteries.
