VPH Flashcards

Question

Discuss how you would define a quality food ?

Answer 1

How would you define a quality food Quality is essentially conforming to requirements or specifications to achieve the same product consistently. - this definition of quality may be different depending on the interest of the producer / manufactuer. User based quality 'fitness for use' Value based ' notion of price for money' To achieve quality you must first define a certain set of characteristics attributes which are required for quality eg in a apple - shiny - colour - crisp - no insect damage - no insecticides on the fruit - sweetness - then set out standards to achieve this quality. - but there are many influences on the final quality of a product product.

Answer 2

Best practice A best practice is a method or technique that has consistently shown results superior to those achieved with other means, and that standard is used as a benchmark Collectively all the techniques / procedures that result in a recognised "best way" of doing somthing eg "best prectice. - are used to maintain quality as an alternative to mandatory laws and can be based on self assessment or benchmarking (against a external standard such as an ISO standard).

Answer 3

GMP and GHP are forms of best practice. GMP; Good manufacturaing processes - Describe the conditions and practices that are nessary for the manufacturing, processing packing or storage of food to ensure safety and wholesomness. - Essentially anything that contributes to that final product is GMP Good hygiene practices (GHP) - are those conditions and measures that contribute to the safety and suitability of food at all stages of the food chain. - GHP are a prerequisite to a risk based approach - can be viewed as a subset of GMP

Answer 4

Why have SOP and SSOP To be consistent a company needs to get all workers to follow the same identified best practice - all workers must follow the same process - to do this companies need documents that include all relevant information detailing how procedures are going to be done. - a method to standardize work practice SOP = standard operating procedure (SOPs) covering all aspects of all parts of the process SSOPs = Sanitary standard operating procedure (are among the most important of any company's SOPs. - cleaning and sanitation - pest control measures

Answer 5

Quality assurance - Focusses on the process of producing the product - aims to assure quality, to prevent the defect occuring - proactive, before the process, during development, during design a management commitment. eg. a farmer creates a plan to produce a product of quality ( disease management, how to safely discard milk, sanitation of site, etc). Quality control Is the day to day verification - Quality control is used to verify the quality of the output or product - is the product or process meeting QA goals - for example identifying defects every day during production -eg. visualisation of milk during and after collection.

Answer 6

The four steps of a quality assurance program 1. Putting in place documented procedures which identify the methods for carrying out each key production task. 2. Recording the results of those actions 3. Checking that the results conform to expectations 4. Implementing corrective measures and preventative actions on all identified programs - to stop identified problems occuring agin.

Answer 7

Process control The most important part of quality control is to control what the staff do - identify exactly what each worker needs to do to produce the quality product - train them correctly - make sure all the detail is performed correctly - by all workers - all the time = process control Process control is the most important part of maintaining quality Identifying best practices and ensuring they are done correctly is a pre-requisite to any food safety approach. Example line manager watching staff ensuring each step of the process complies.

Answer 8

**How to control food safety hazards** ** Product based inspection** - inspection is a screenshot, which is not representitive of the product or procedure - requires a large number of samples to be effective - at the mercy of the 'lab' in which some are unacredited and unreliable. - if a fault is identified there is no mechanism to identify where in the process the fault occured or how to prevent it in the future. ** Risk based inspection** All necessary control measures are identified, and their control is inspected. 1. identify hazard 2. identify all risk factors associated with the hazard 3. develop / create a quality and safety program that controls the identified risk 4. inspect control of the risk factors - this adopts a preventative approach - not a reactive approach - samples may still be collected but not as a sole means of control. - better use of resources and compliance eg. observation of apple picking - thrown apples into basket are know to get bruised - are apples being gentle placed into basket

Answer 9

Risk based inspection To focus inspection on risk factors (for food borne disease in this case) it must first be determined what these risk factors are. Most risk factors are contrary to known good manufacturing practices (GMPs), accepted hygiene or health guidelines and bench marks We know - we must was our hands after handling raw meat, or after the toilet - drinking unpasteurised cow's milk is known to be a risk for some hazards - throwing apples into a basket will cause bruising It is on these risk factors that the inspector must concentrate during inspections to have a meaningful impact on food safety; inspect for the pressence and control of risk factors.

Answer 10

How are risk factors identified **A risk assessment** A risk assessment must identify all risks associated with a specific hazard / disease - specific basis where possible - it must identify the risk for any given hazard - every disease of concern must be assessed seperately - qualititive risk assessment can assist a risk manager in priority setting and policy decision making - qualitive risk assessment is based on data forming a adequate basis for numerical risk estimation "Codex Alimentarius" The risk estimate will be a simple statement that the risk is high / medium / low We can no simply address the overall risk related to a combination of hazards.

Answer 11

Risk based food inspection 1. identify hazards of concern 2. identify risk factors 3. develop create a quality and safety program that controls the identified risk 4. inspect for control of risk factors The primary purpose of a risk based approach is - by focussing on the risk the inspector will make better use of existing resources without overlooking non-compliance - ensure the control system works all the time so that safe food products are consistently produced - reduces problems associated with sampling - identifies non compliance to a specific risk so that future monitoring and improvements may be made.

Answer 12

Product-based inspection - this is a snapshot, it is not representative of all the product or procedure - requires a large numbers of samples to be effective and accurate = expensive - reactive after a problem occurs Risk based inspection - all necessary control measures are identified - testing of whether these control measures are being implemented - requires less sampling - preventitive measure as observation of uncompliance is observed and corrected during production - ensures consistent production - judge how well the company's quality and safety management system has been designed and followed. -

Answer 13

Quantitative risk assessment It may be desirable to undertake a quantitive analysis (QRA quantitive risk assessment) Quantification involves developing a mathmatical model to link various aspects of the epidemiology of a disease, which are expressed numerically. Deterministic From determination, which means a lack of free will - model outcome is entirely determined by the intial conditions and a specified set of equations. eg population = initial population size + growth growth rate Stochastic Incorporates randomness and uncertainty into the model to account for variability in the system's inputs and parameters - instead of producing a single outcome, stochastic models generate multiple possible out comes - this reflects the inherent randomness in the system

Answer 14

**Risk based inspection** **Qualitative risk assessment common** - "Codex Alimentarius" - is based upon data which forms an adequate base for numerical estimations - permits risk ranking or seperation onto descriptive categories of risk - assist with priority setting and policy decision making - the qualititive risk estimate will be a simple statement that the risk is high / medium / low. Quantitive risk assessment Quantification involves developing a mathmatical model to link various aspects of the epidemiology of the disease which are then expressed numerically.

Answer 15

**Risk assessment** - must identify the risk for any given hazard - consider each disease of concern seperately - diseases specific base where possible **Risk analysis (risk management and risk communication combined with risk assessment and hazard identification are referred to as a risk analysis)** - a risk analysis can use both qualitative and quantitative terms to determine the level of risk probability (liklyhood) - can be scored 0-1 x consequences - includes a risk estimation a integration of the release, exposure and consequence assessments

Answer 16

BIRA - Biosecurity import risk analysis The department underatkes a range of risk analysis in response t requests to import goods into Australia - where thoses goods have not been imported before BIRA consider the level of biosecurity risk that may be associated with the importation of a good and identifies appropriate ways to manage these risks. - BIRA is a regulated response provided for in the biosecurity ACT and the Biosecurity regulation. - the aim of BIRA is to provide importing countries with an objective and defensible method of assessing the disease risks associated with importation of animals, products, animals genetic material, biological products and pathological material.h

Answer 17

**ALOP = Australia's appropriate level of protection** Australia has a low risk preference but its not zero - risk managment measures are proposed to reduce the risks to an acceptable level - if the risks cannot be reduced to an acceptable level, the goods will not be imported into Australia until measures are identified - biosecurity risks are assessed on scientific information

Answer 18

Sanitary and phytosanitary measures (SPS) agreement WTO (world trade) memebers are entitled to maintain a level of protection they consider appropriate to protect life or health within their territory. This is called ALOP (appropriate level of protection) - SPS measures are used to manage risk to allow members to achieve their ALOP eg. sourcing stock from disease free populations Australias ALOP is contained in the biosecurity Act 2015 and is applied in risk analysis conducted by the Department of Agriculture, water and the environment - eg Australia wishes to remain FMD free / Australia insist certain measures to be taken on imports.

Answer 19

Risk assessment A risk assessment must identify the risk on a hazard/ disease-specific basis where possible - it must identify the risk for any given hazard / disease of concern separately, not simply address the overall risk. Risk management The process of deciding upon and implementing measures to address the risks identified in the risk assessment, whilst at the same ensuring negative effects on trade are minimized. - eg quality assurance schemes at farm level - consumer education or packaging for safe handling at home - monitoring once the control measure is in place (and review) to ensure all activities are carried out to see whether control measures are working.

Answer 20

Harmonisation - means making the playing field level for all countries - enable different countries to adhere to the same standards - make international trade more fare **But why is harmonisation required** - most overseas markets are subject to barriers tariffs (tax on imports) and quotas (quantity limit. - but there is also unfair competition in the form of subsidies, technical imposts - ever country has different standards some very strict - some less so - this makes farmers in some countries less competitive, and they may lose market share to cheaper imports (which may not be required to meet the same strict standards) - to make the trade fair requires harmonisation of the standards.

Answer 21

WTO World trade organisation The world trade organisation is an organisation that supervises and liberalises international trade. The role of the WTO; - it provides a framework for negotiating and formalising international trade agreements - acts in a dispute resolution process aimed at enforcing participants adherence to WTO agreements International trade agreements developed under the WTO emphasise the need for regulations governing international trade in animals and foods to be based upon 1. Science and 2. Risk analysis

Answer 22

Technical trade barriers A technical barrier is a barrier thats prevents entry of product into certain markets that is not required on a health or disease related basis. AGAHP Australian Government Authorised Halal program. - provides assurance to muslim customers that imports from Australia are indeed Halal - Several Islamic Organisations in Australia are approved by the Federal Government and responsible for providing Halal inspection, supervision and certification. - AGAHP is a market access program

Answer 23

(SPS) Sanitary and phytosanitary agreement - recognises the need by WTO members to protect themselves by SPS "measures" - Sanitary = relating to human or animal health - Phytosanitary = relating to plant life or health - these are commonly known as SPS measures SPS measures must minimise impacts on trade where possible 1. Is applied only to the extent necessary to protect human, animal or plant life or health 2. Is based on Scientific principles 3. Is not maintained without sufficient Scientific evidence 4. Must not arbitarily or unjustifiably discriminate between members where identical or similar conditions prevail 5. shall not be applied in a manner which would constitute disguised restriction on International trade. Eg Us wishes to extport meat to the EU (which refuses based on hormone additives) - debate on whether this is a fair restriction on trade.

Answer 24

Regionalisation and equivalence are two key principles of the SPS. Regionalisation This is a concept where an area of a country is recognised as pest or disease- free or with low pest / disease prevalence; and trade from such areas is allowed This occurs even if the health status in the rest of the country is not favourable. Equivalence Equivalence of SPS measures does not require duplication / sameness of measures - it requires the acceptance of alternative measures that meet an importing member's ALOP (appropriate level of protection).

Answer 25

SPS Sanitary and phytosanitary measures / The SPS agreement The SPS measures are as follows; 1. is applied only to the extent necessary to protect human, animal or plant life and health 2. is based on scientific principles 3. is not maintained without sufficient scientific evidence 4. must not be arbitrarily or unjustifiably discriminate between members where identical or similar conditions prevail 5. shall not be applied in a manner which would constititute a disguised restriction on international trade.

Answer 26

**The precautionary principle ** It allows members to make decisions regarding importing products on with suspected health concerns - when extensive scientific knowledge on the matter is lacking. - States that if an action or policy has a suspected risk of causing harm to the public or environment, in the absence of Scientific concensus that the action is harmful. - The burden of proof that it is not harmful falls on those taking the action. Example - This is what Europe is using to avoid the importation of American meat which contains hormonal additives - The Americans must prove hormones in beef cause no harm

Answer 27

A free trade agreement (FTA) Is an International treaty between two or more economies that reduce or eliminates certain barriers to trade goods and services, as well as investment.

Answer 28

Food standards Australia New Zealand. (bi national Government agency) Responsible for - developing and administrating the Australia New Zealand food standards code - contributes significantly to several CODEX committees

Answer 29

SPS = Sanitary and phytosanitary agreement ALOP = Appropriate level of protection The SPS agreement recognises all WTO members right to protect themselves from human, animal or plant life or health risk posed by introduction. - the SPS provides for biosecurity and quarantine - This is provide for so the Country is able to maintain their ALOP.

Answer 30

The three sisters - setting international standards for SPS measures. **(WTO) World trade organisation** **Codex Alimentarius** - Joint FAO/WHO food standards program - which develops and encourages implementation of standards of practice and guidleines, recommendations covering all aspects of food safety **(WOAH) The world organistaion for animal health** - ensuring transparency in global animal disease + zoonosis - publishing health standards for trade in animals and animal products promoting Veterinary skills and improving the safety of food of animal origin **(IPPC) International plant protection convention** - coordinates work to prevent the spread and introduction of pests of plants and plant products.

Answer 31

Contact points SPS agreement **NNA National notification Authority/ Federal department of fishery and forestry** - single government authority responsible for implementing on a national level and notification of the SPS agreement **NEP National enquiry point NEP** - responsible for answering all reasonable questions and providing relevant documents regarding all existing SPS measures

Answer 32

Australain and New Zealand standard diagnostic procedure - the primary objective of ANZSDP is to standardise test procedures - ensure consistency between labs using methods for their optimal accuracy, sensitivity, specificity and robustness Test and reagents are consistent with the World organisation for animal Health (OIE).

Answer 33

Food standards Australia New Zealand (FSANZ) This is bi national Government agency responsible for developing and administering the Australia New Zealand food standards code. - prepares the standards across the supply chain - set residue limits

Answer 34

With held from slaughter (re-inspection every 24 hours) This disposition is very rare - some animals must be identified, segregated and given 24hours before a decision can be made - require a new ante mortem inspection before they can be accepted Potential reasons to withhold from slaughter 1. prevent unnecessary contamination ( heavily soiled) 2. prevent production of a poor quality product eg glycogen reserves depleted / poor meat quality 3. Animal is affected with a disease/abnormalities which can be better assessed within 24 hrs - hypocalcaemia - allows clinical signs to develop - calving at abattoir fatigue / allows recovery time - shows signs of disturbed behaviour (stress, physiological pyrexia) rest will improve meat quality

Answer 35

The AMIC The Australian Meat Industry Council (AMIC) Have made; Industry animal welfare standard for livestock processing establishments preparing meat for human consumption This standard provides details that can be independantly, observed and measured that will 'prove' the abattoir is following the welfare requirements.

Answer 36

Implementing Slaughter house standards. The Australian meat industry council (AMIC) is the industries peak body representing livestock processors. 'Australian livestock processing industry animal welfare certification system' or AAWCS 1. Vocalisation of cattle - no more than 3% active vocalisation during active handling - the establishment must demonstrate it has procedures in place to moniotr animal handling during unloading and upto the entry for restraint - documented procedure - demonstration of the monitoring process - monitoring records 2. Auditing of electrical stunning Fewer than 1% of animals should be observed to vocalise due to energising of the electrode, before firm positioning on the head "hot wanding" - documented produre - demonstration of monitoring process - monitoring records

Answer 37

Anti mortem inspection Only appropriate animals fit for slaughter for the purpose of producing meat and meat products for human consumption are slaughters - carried out by a meat safety inspector Deposition; Passed for slaughter subject to conditions. The animals may continue for human consumption provided; 1. The vet thinks part of the carcasse are suitable for consumption 2. the issue is not systemic or malignant Treat as suspect animal so they do not contact normal healthy animals prior to slaughter - often processed at end of shift with a distance between them and the next animal

Answer 38

Collaboration with Australian meat processor Corporation (AMPC).

Answer 39

Anti mortem inspection Depositions are legal statements about the suitability One of the following dispositions must be applied by an "authorised officer" (a vet in export plants) 1. Passed - for unconditional slaughter (they are good no conditions applied) 2. Passed for slaughter subject to conditions - specified by the meat saftey inspector 3. Withheld from slaughter - re-inspect every 24 hours; relatively rare 4. Condemned - rejected entirely for slaughter (rendered into meat and bone) A meat inspector can only pass an animal for slaughter if they know the place of production of the animal, or the area it was captured.

Answer 40

Australian Standard 4696:2023 - the law Sets out the outcomes required for; - the receipt and slaughter of animals - ante and post mortem inspection dispositions - the dressing of carcases - the processing (including further processing), - packaging - handling and - storage of meat or meat products whether for domestic use or for expo By complying with AS 4696, The Australian Government and Industry standardise and ensure compliance with CODEX (and WTO) requirements.

Answer 41

AMIC allow - no more than 3% of cattle vocalise when under direct and active handling in races, crowd pens and moving into restraint. - no more than 5% of cattle vocalise when head restraint is used - no more than 3% cattle and 10% pigs should be vocalising for the 100 measured, regardless of the cause.

Answer 42

Transport Fit to load An animal is not fit for a journey if it is; - unable to walk on its own by bearing weight on all legs; or - severely emaciated - visably dehydrated - showing visible signs of severe injury or distress - suffering from conditions that are likely to cause increased pain or distress during transport - blind in both eyes - known to be, or visually assessed to be near (with two weeks) of partuition, as specified in the species requirements, unless time off water and journey is less than four hours If any arrive in what may be an unfit condition, than management is required to raise an animal welfare incident report (AWIR) + notify the authorities.

Answer 43

Passed for slaughter subject to conditions The vet/ inspector applies any condition This is ususally used in a case - animal is affected with a disease / condition that at postmortem might result in condemnation of the carcase or parts of the carcase - includes any euthansia on site (emergency kill) These animals can still be considered for human consumption provided 1. The vet consider parts of the carcase are suitable for human consumption 2. the issue is not systemic or malignant

Answer 44

No more than 5% of pigs are allowed to vocalise when being moved into the restrainer.

Answer 45

A meat safety inspector must carry out an ante mortem inspection in accordance with the approved arrangement. (AMI must be within 24 hours of slaughter) The inspection is to 1. Detect the pressence of exotic and notifiable disease 2. Prevent slaughter of any animal that shows signs of a condition or disease which would make the carcase unsuitable for human consumption 3. seggregate animals animals showing signs of or having a suspected illness so they may be slaughtered seperately and given a detailed post mortem examination 4. Prevent animals that are groosly contaminated with faeces, dirt, dust or other material from entering the floor 5. Ensure humane treatment of animals, including those that are injured

Answer 46

Conditions which would result in the inspector condemning the animal - dying or moribund - affected with adisease or condition that makes them unacceptable for slaughter - pyrexia >40.5 bovine + ovine, >41 pigs - systemic toxaemia / septicaemia / bacteremia / viraemia / parasitaemia - emaciation - generalised oedema This is denying someone an income, you must be able to justify your deposition.

Answer 47

There are many types of stun available AS4696:2023 - stunning, a procedure for rendering an animal unconcious and insensible to pain. Thee are many different types of stun both reversible and non - reversible - captive bullet - shooting, free bullet - head to heart electrical (cardiac arrest) - prolonged carbon dioxide - percussion stunner - head only / electrical current - controlled atmosphere stunning

Answer 48

Stunning =A procedure for rendering an animal unconscious and insensible to pain. NON reversible stun (might be immediate kills, stun kills) - penetrating captive bolt - shooting / free bullet - head to heart electrical (cardiac arrest) - prolonged carbon dioxide A reversible stun (Dose not kill; stun only - can be suitable for Halal). - Pneumatic non - penetrating, percussion stunner - head only electric stunning (heart remains non - affected) - limited time exposure to carbon dioxide

Answer 49

**The signs of an effective stun** ** The signs of an effective electrical stun** (Tonic phase 10-12 sec) - forelegs extended hindlegs tucked into body - immediate collapse - no rythmic breathing - head raised - no corneal reflex - fixed, fully dilated pupils. **The signs of an effective mechanical stun** - animal collapses immediately (no jelly legs) - eyes are fixed (no movement or rotation) dilation - no corneal reflex - no rythmic breathing (gasping is different) - no righting reflex, floppy head straight back (easiest to see in cattle as the tail head becomes limp).

Answer 50

Indicators of an ineffective stun in a pig If the pig blinks within five seconds of the stun this indicates an ineffective stun. - not an immediate collapse - corneal reflex - non dilated pupils - rhythmic breathing - strong jaw tone

Answer 51

Poorly maintained equipment is one of the main welfare issues when it comes to stunning. Captive bolt - what happens when a captive bolt mechanism is rusty or the catridge is damp - F=MA mass of the bolt remians the same but velocity is reduced so may not achieve an effective stun Electrical stunning - poorly maintained equipement could potentially increase the resistance which will reduce current - this affects welfare - eg dirty electric tongs, rusty tongs Inadequate restraint equipment

Answer 52

The stick to stun interval SSI: The time from the commencement of stunning (reversible) to the cutting of blood vessels. After a reversible stun all animals must be subject to a second step - a killing step otherwise the animal will regain sensibility. 1. Bleed them (cutting both carotid arteries or the vessels from which the arise 2. pithing Time is crucial before recovery commences eg. after a non -penetrating percussive stun , cattle must be bled within 30 seconds

Answer 53

Pithing: Destroy the brain and brainstem with a rod - this animal can not then be used for human consumption. This method is only ever utilised in a welfare emergency - for example a broken leg animal arrivd on the truck - ensures post stun the animal is dead.

Answer 54

The main welfare issues surrounding stunning of animals 1. Poorly maintained equipment 2. Poor restraint 3. Incorrect positioning

Answer 55

The main forms of religious "ritual" slaughter permitted in Australia are Halal Kosher Halal cut = neck cut / neck stick across the throat - severing the carotid arteries and the jugular veins, the oesophagus and trachea but leaving the spinal cord intact - in Australia performed immediately following reversible stunning Shechita dose not allow any form of stun (banned in NZ).

Answer 56

Two main welfare issues of religious slaughter **Restraint** - how the animal is held and handled - this is the larger concern ** Slaughter without stunning (Shechita)** - distress and pain associated with the neck cut - less than a very sharp blade - the head / neck being allowed to flex stopping blood flow, increasing pain when cut wound edges come together, impeding blood flow and delaying death

Answer 57

False aneurysm This is caused by blunt knives - a sawing motion will cause trauma to the carotids, due to the elastin fibres in the artery walls - carotids withdraw and partially seal (withdraw into connective tissue sheaths) - haemorrhage causes distension or ballooning of the sheath which may apair as an aneurism This partial blockage delays the fall in central and cerebral arterial pressure Thus resulting in an unacceptable delay in bleeding out and maintenance of sensibility.

Answer 58

Post mortem (A) A post mortem is a legal requirement: AS 4696:2023 states 10.1 " Post mortem inspection of each carcasse and its parts is carried out by a meat safety inspector" (B) Meat safety inspector

Answer 59

The postmortem dispositions Australian Standard 4696:2023 One of the following dispositions (legal judgements) must be applied: 1. Passed for human consumption 2. Retained for final disposition 3. Unfit for human consumption and may be recovered for animal food 4. Unfit for human consumption and may be recovered for pharmaceutical material 5. Condemned and rendered (often processed into fats and meals)

Answer 60

Post moretem inspections are limited A traditional meat inspection is not appropriate to all situations 1. Major hazrads in meat are microbial and not visable - there can be healthy carrier animals - salmonella in beef, pork - E.coli beef - Yersinia in pork 2. A knife incision could contribute to comtamination and this would not be seen on post mortem. In these situations, postmortem inspection is not enough, a risk based approach is needed.

Answer 61

The use of lymph nodes in post mortem examination. The lymph notes can be used to determine if a disease has spread - what can spread inflammation, neoplasia, infectious agents - check regional lymph nodes For example; Salmonella - viewing of the mesenteric lymph nodes may contribute to overall judgement of generlised or systemic salmonellosis (full PM typically required). - lymph nodes are limited and not all diseases will be appraent

Answer 62

Post mortems are limited, as many types of disease (bacteria salmonella, E.coli) may cause a risk to consumers without being visable on post mortem. In these situations, postmortem inspection is not enough, and a risk based approach is neccessary. - control then becomes more about cross contamination and hygiene than pathology.

Answer 63

The main goal of a post mortem; is product safety and public health Post mortem inspection 1. Identifies diseases and unwholesome meat - to prevent it being sold for human consumption 2. Breaks the cycle of disease - prevents transmission between animals and humans; and animals - animals 3. Assists with the trace-back of diseases to the property of origin 4. Assesses whether hygiene and good manufacturing practices are being followed - during slaughter and dressing to maintain the wholesomeness of the product. 5. Animal welfare - post mortem is an important aspect to verify that animals have been handled humanely. eg. blood splash

Answer 64

Reasons to condemn on post mortem examination. Check scheduke 3 A.S. 4696 Condemn an animal's carcasse of; - inflammation / infection is generalised, systemic disseminated - Immature (very young eg wet unbilicus and soft soft hooves - Aesthetics - odour, pigments - Neoplasia, with evidence of spread - severely emaciated - Generalised oedema - Severe dehydration - Pigments (lipofuscin), causes not harm but appears poorly to the consumer -

Answer 65

Valvular endocarditis - withouts systemic signs of illness. Disposition 1. Passed for human consumption.

Answer 66

Reason to trim - condemn parts only The crital factor is spread. Something localised, contained or regional (ie. it hasn't spread) - can be trimmed - bruises - masses - abscesses - minor or low grade / localised focus can be trimmed Example; Chronic pericarditis - the carcase can be ok if there is no systemic spread.

Answer 67

**Sanitary carcase dressing** After bleeding the animal enters the kill florr (production floor) Dressing of cattle - starts with removal of horns, hooves (at the metacarpophalanggeal joint, external genitalia and udder - the intestines and inedible material are removed from the slaughtering and dressing area as soon as inspection permits. **There is a sanitary sequence that must be followed in order to minimise contamination eg order of cuts** - equipment and people must be clean - staff must move from clean to dirty areas only ( or wash and change) - meat must only contact surfaces designed to come into contact with meat - must not contact other carcasses - cuts are orderd to prevent roll back (external hide must not touch the clean meat) - birds and skin on mammals (pigs mainly) must go through a scalding tank (60-64 degrees C to loosen skin and feathers) - no carcase dressing to be carried out on the floor

Answer 68

The legal requirements in terms of chilling. (A beef carcasse must be placed in a chiller within 2 hours of slaughter) Within 24 hours must achieve legally - A temperature of 7 on the surface of all carcases sides and quarters - the deep butt site must be <7 in the next 24 hours Cracase part / box - a temperature no greater than 5 at the site of microbiological concern (ie, the thermal centre).

Answer 69

The refrigeration index (this is used to assess if the chiller is doing its job). The refrigeration index asesses the effectiveness of the chiller - a deterministic model that predicts the expected growth of E.coli on meat from temperature and other data. Note it dose not matter how clean or dirty the carcassse is - RI model only assess how likely E.coli is to grow on the product in question, given how well the individual chiller performs.

Answer 70

**Site of microbiological concern** **1. The surface of a side of beef** - this is where the beef has been handled by staff, and the site of any (bacterial) contamination. - side must be 7 within 24hrs ** 2. The centre of a cartoon or box** - where bacteria will be the warmest and replicate the longest. - centre must be 5 within 24hours

Answer 71

Cold chain In order to control bacterial growth on the meat, it is important to keep the meat cold ... all the time - A cold chain is an unbroken temperature - controlled supply chain - it is used to help extend and ensure the shelf life of products eg milk meat Example one Vaccine - relevant to anything that is temperature sensitive - deleiver vaccines in a potent state from manufacture to actual vaccination - manufacture - air transport - regional reception - district story - clinic - (VVM) vaccine vial monitor changes colour when the cold chain is broken. Example two - meat, milk, eggs

Answer 72

Hazards The pressence of 'objectionable' material or any substance which may compromise food safety or wholesomeness. A clean hyde ; 10^6 - 10^10 bacteria per cm ^2 - including staphylococci, pseudomonas, yeast etc Gut contents: 10^11 / g faeces Sanitary carcase dressing = seperate the contaminated parts of the animal outer dirty and the gut from contact the clean meat.

Answer 73

During dressing Birds and skin on mammals (pig mainly) must go through scalding - scalding is done in 60-64 degress water to loosen the hair and / or feathers prior to their removal - bleeding must be substantially done pre-scalding Pig carcases will alos be polished to remove any remaining hair.

Answer 74

A beef carcasse must begin chilling within two hours of being killed. - within the following twenty four hours the following temperatures must be reached A. Surface temperature of carcasse 7 B. Temperature of deep butt site 7 C. temperature at the centre of a meat box / cartoon 5

Answer 75

Minimising contamination; poultry killing red meat is cooled with air however, poultry can also be chilled by immersion in water, - particularly if the carcases are to be frozen subsequently - if temperature is not tightly controlled water chilling can be a significant source of bacterial contamination

Answer 76

One generation of replication at 20 degress takes one hour

Answer 77

Boning out The carcase is cut into - primals, sub primals, off cuts and trimmings - this can happen at the abattoir or at independant boning rooms Unless carcase / carcase parts are brought of the chiller they must stay at 7 degrees C or 5 degrees C respectively (max its often lower)

Answer 78

Boning room Warm boned = - blast chilled 4-6 hrs - and then boned out at 25 Cold boned = <7 - harder fat but easier to work slice - reduced contamination - room must not be >10

Answer 79

**Drip loss** Drip loss: myoglobin not haemaoglobin - there should be no clotting visable - clotting = improper bleed-out which will affect meat quality and hygiene **What affects drip loss** - muscle sarcomeres contract during rigor - increased shortening at temperatures <12 degrees when ATP is still present. *- The muscle fibres shorten very little if the muscle enters rigor mortis at 10-15 degrees. * - it should be noted that drip los can not be avoided and primal cuts will lose 1-10ml/kg in the first 48 hours.

Answer 80

t**The ultimate PH goal;** Freshly slaughtered beef 7.1PH falls to and stabilises around PH 5.7-5.5 with 18 hours. **What causes the drop in PH post mortem** - Because there is anaerobic metabolism post mortem (no O2) = anerobic glycolysis - pyruvate is converted into lactic acid - the lack of circulation post mortem means the lactic acid builds up in the muscle and PH drops **Two factors determine post mortem metabolism and the final PH of the meat which are; ** 1. Glycolytic potential (GP), the amount of glycogen in the muscle at the time of death 2. temperature ** These factors are in turn affected by;** - starvation (glycogen levels - vigorous muscle contraction (ATP and glycogen levels

Answer 81

**PSE Pale soft exudative = Pork** (similar to heat shortening) - rapid glycogen use (glycolysis) and depletion immediately prior to death - high lactic acid levels build up in the muscle before slaughter - PH of meat shoots down to quickly post mortem: PH reaches 5.2-5.6 within one to two hours while >35 degreess **A high temperature and low PH - muscle proteins denature** - loss of colour, firmness, reduced water holding capacity and poorly used or wasted meat.

Answer 82

**Rigor mortis** ** Rigor mortis is determined by ATP levels.** - an exhausted animal may go into rigor with a relatively small PH change (alkaline rigor. ** What actually happens** - muscles want to contract - it takes energy in the form of ATP which bined to the myosin head, and the link between the myosin head and the actin weakens - myosin head detaches = relaxation - post mortem ATP is maintained by the break down of glycogen in the muscles ** First delay phase** - muscle is still extensible, due to remaining ATP postmortem - disconnecting the actin mysosin cross bridges ** The onset of rigor** This occurs when there is a sharp decline in ATP - reduced ATP - less relaxation of the cross- brideges - eventually the ATP levels fail to regenerate, and relaxation can not be maintained.

Answer 83

Calcium is the key The sarcoplasmic reticulum releases Ca2+ into the fluid surrounding the myofibril in order for contraction to take place - Ca2+ binds to troponin which affects tropomyosin, uncovering the actin binding site - Ca2+ causes the binding site for the myosin head to become available allowing contraction to occur. ** At 12 degrees** The sarcoplasmic reticulum is damaged and becomes unable to take back Ca2+ - preventing contraction of the muscle.

Answer 84

**PSE Pale soft exudative** (Rapid glycogen use (glycolysis) and depletion just prior to slaughter causes high lactic acid to build up readily in the muscle. - PH reaches 5.2-5.6 within 1-2 hours PM while >35 degrees **PSE risk factors and prevention ** **Rest on arrival** - pigs two hours minimum to allow lactic acid to dissipate - cattle require 24 rest period - avoid handling stress and burning up glycogen levels Rapid chilling - this may help with control in slaughtered animal (particularly pigs, with high lactic acid levels.

Answer 85

DFD Dark firm and dry Prolonged (long term) stressors use up glycogen in the muscles - in pot mortem little anaerobic glycolysis occurs because of low glycogen levels, therefore lactic acid production is minimal - this results in a high PH 6.2 -6.5 (normal 5.5-5.7) - high Ph prevents conversion to oxymyoglobin = dark firm meat - tendency to take off flavours - increases bacterail spoilage - poor keeping quality

Answer 86

**DFD = dark firm dry meat** This is caused by (long term) stressors using up the glycogen supply/ Dark cutting meat is defined by (MSA Meat Standards Australia) as meat with a ultimate PH >5.7 What strategies can we employ to prevent this Risk factors = long term stressors Solution; feed and rest for 24-48 hr prior to slaughter - may also have some environmental and hereditary factors.

Answer 87

The abattoir window = requires carcasse Ph to pass through PH 6.0 between 15 to 35 degrees C. blue = ideal PH and temperature change for quality meat Green = heat shortening / low PH high heat Red = cold shortening

Answer 88

Cold shortening (this occurs when meat is too rapidly cooled) This occurs when the PH decline is too slow, which means it remains high while the temperature falls (red line). **Cold shortening results;** - results in inedible meat - extremely tough, cold shortened meat The widespread use of electrical stimulation has resulted in cold shortening being unlikely in most processing plants - low prevalence of cold shortening. ** Pathophysiology** - extreme contraction of muscle fibres <12 degrees pre rigor when ATP is still present - cold shocks the sarcoplasmic reticulum causing it to realese stored Ca2+ - this results in maximum Ca2+ in the myofibril resulting in maximal contraction in the pressence of ATP - nothing can stop this contraction until rigor sets in and ATP is exhausted.

Answer 89

Cold shortening = maximal contraction due to pressence of Ca2+ and ATP in the myofibril. Cold shortening and the solution 1. Delay chilling - 10-12 hours - not always possible due to the proliferation of bacteria (pathogen and spoilage organisms) 2. Continue chilling aggressively but artificaially use up the ATP and advance rigor before 12 degrees is reached - apply electricity to the carcase

Answer 90

Heat shortening (The PH drops while carcasse temperature remains high). ** This occurs if the PH declines ** - this has undesirable effects - an increase in toughness and meat which is very pale, sometimes watery (PSE) - PSE is very prominent in pork - two tonning in some cuts of meat The toughening occurs due to inactivation of proteolytic enzymes that leads to reduced tenderisation during the aging process - reduced water holding capacity **How do we prevent heat shortening / similar to PSE** - sufficient rest for animals allowing lactic acid to diccipate -

Answer 91

A pricing grid A grid is value based trading - where products are priced according to objective measurement of what is valued by the customer - themore accurately a product can be identified, measured and priced according to its value for a particular market - the higher the degree of value based payment.

Answer 92

The muscle fibres shorten little if the muscle enters rigor mortis at 10-15 degrres C

Answer 93

Electricity is applied to induce rigor mortis by using up the available ATP. - the lower the frequency, the greater the effect on PH - damage to meat is minimised by adjusting the electrical energy to the minimum required and limiting the time of application.

Answer 94

Of all the proteins in meat myosin and actin play a critical role in the changes that take place in meat as it cooks. Myosin denatures arounds 40 degress - this denaturation changes meats texture from raw to cokked but still tender. Actin denatures at 66-73 degrees C - this protein is responsible for toughening of the meat fibres and moisture loss. This means the optimal temp of cooked meats = 60-67 (medium) to prevent denaturing the actin filaments.

Answer 95

Aus meat - provides a common description - Aus meat develops maintains and reviews accreditation standards. - The Australian meat industry and standards committe is part of Aus meats, and is responsible for setting the standards for the Australian meat industry Information HAM Handbook of Australian meat - a catalogue of products available from the carcase.

Answer 96

**Aus meat (not for profit industry)** Develops, maintains and reviews accreditation standards. **Accredation for abattoirs** Aus meat offers accredation programs for meat processing facilities including abattoirs and boning rooms. - all export beef, sheep, goat abattoirs and boning rooms must be accredited by Aus-meat under federal legislation **The Aus meat Launguage** - Objective descriptions to describe meat products to meet market requirements - accurate way to order meat products - chiller assessment - beef carcase evaluation - a grading system where common measurements are used - standardised product descriptions as consumer expectations vary

Answer 97

**Aus meat - launguage ** Aus meat provides descritions to describe meat products accurately to meet market requirements (standardised) - customer demands vary - standardised descriptions provides customers with an accurate way to order meat products to suit their needs - used by the producer, meat processor, boning rooms, wholesalers and food service organisations - same launguage used through out Australia Includes - The Australian beef carcasse evaluation scheme - Chiller assessment

Answer 98

Carcasse trimming. (Hot) standard carcase weight - Described by Aus meat - Provides exact details on trimming the carcase correctly: Aus meat standard carcase trim. - CCP - ensures product is standardised Upto 3% of body weight is lost in 24hrs due to drip loss - therefore the carcasse must be weighed hot (within two hours of slaughter) after the stanadard trim).

Answer 99

**Fat measurement - Aus meat ** P8 site on rump forward of tail bone, above short ribs P8 standardised measurement - P8 is a fat assessment that determines suitability for particular markets - objective data to determine the destination of carcasse - the P8 site is less susceptable to damage by the hide puller (previous version was susceptable) *standardised fat measurement

Answer 100

Off the hooks trading (OTH) OTH refers to the marketing of animals directly from the farm to the abattoir. _ abattoir attempts to meet customer demands - abattoir wants a standardised product from the producer which meets these needs - if producer can meet these specifications they may be payed a premium. - Abattoir assesses carcass quality characteristics - vendor and buyer usually agree on payment criteria prior to slaughter Benefits of OTH - feedback for farmer on their carcasse performance (enables a better understanding of market demands and signals) - direct delivery (reduced carcasse damage - provides a true reflection of the real worth of a carcasse

Answer 101

Brusing Millions of dollars a year in meat are lost when bruises are trimmed out bruising results from - poor handling excessive use of prodders - handling method changes Bruising score Subjective assessment of carcasse brusing - there are larger penalties when bruising causes trimming of quality meat site

Answer 102

**Pricing Grid** A grid is value based trading - where products are priced according to objective measurements - the objective measurements of what is valued by the customer - the more accurately a product can be identifieid, measured and priced according to its value in a particular market (the higher the degree of value based payment). **Good records and more accurate value based trading will reveal which cattle and producers are most valuable** - farmers must understand and select markets which suit their product - meet abattoirs specifications / make product more valuable - where a producer consistently achieves a high level of compliance to a required specification - they will receive price premiums and be sought out by processors (abattoirs)

Answer 103

Cattle dentition Determines categories for beef (correct description) Note - times at which teeth erupt vary - influenced by breed and nutrition - cattle under rough feed conditions

Answer 104

Feed back to the farmer from abattoir This is crucial as it enables the farmer to make management decisions to better meet market demands.

Answer 105

Meeting market specifications Supplying beef that meets the individual market specifications of customers - Japan, Suadi Arabia may want different attributes - meeting these attribute qualities allows market access for the producer and increases producer profitability - end users of stock, including feed lots and bee processors, pay premiums for even lines (consistency) of cattle that fit specifications - those that do not are discounted Think "quality" a product meeting defined criteria, delivered consistently

Answer 106

Meat standards Australia "accurately predicts eating quality for individual beef muscles". - MSA graded meat is voluntary - labels advice correct cooking methods for each cut - Three grades MSA3, MSA4 and MSA5 - MSA meat covers aging between 5-35 days - all meat aged a minimum of five days, grade can change with more aging - higher number better

Answer 107

Hot standard carcase weight - the carcasse is weighed hot post trim but within two hours of slaughter.

Answer 108

Accredited by Aus meat This is not required for - pigs nad domestic abattoirs are optional - wild game, poultry, deer, buffalo etc are not accredited

Answer 109

3% of body weight can be lost in 24 hours due to drip loss.

Answer 110

Best practice A best practice is amethod or technique that has consistently shown results superior compared to other methods. - used to maintain quality - set as a bench mark, or self assessment - the idea of best practice is a feature of accredited management schemes such as ISO 9000 and ISO 22000 Risk based approach (efficient) - We complete a risk based assessment through the application of best practice - identify risk - document procedures to reduce eliminate risk - ensure best practice procedures are being applied every time

Answer 111

GMP = Good manufacturing practices For example procedures which could reduce E.coli contamination - dry curfew prior to transport, reducing manure volume - regular hosing concreate floors - final wash of animal potable water - vermin control GHP = Good hygiene practices - a subset of GMP

Answer 112

WI Worker instruction A SOP covers all aspects of all parts of the process. **A worker instruction (included within a SOP)** - People will have different roles within an SOP - each individual needs to know exactly what they have to do to fit in with the SOP - The work instruction gives details of an individual's duties - if they follow WI correctly, they will be doing their bit of the SOP.

Answer 113

Controlling the process **1. The most important part of quality control is the work instruction (contained within an SOP)** - get the detail of WI right - make sure all the detail is performed correctly, by all workers, all of the time = controlling the process or process control Process control is the most important part of maintaining quality **2. Product monitoring** 3. Assess defects in the final product to verify the effectiveness of carcasse dressing and sanitary process (ie. that the work instructions were followed correctly).

Answer 114

Process control Assess how well each worker is following and complying with their work instructions - if they are should be very few is no issues with the product. A better measurement - requires less sampling (cheaper) - easier to identify where best practice is not being achieved and immediately correting procedures.

Answer 115

Product monitoring assessment of defect in the final product Product monitoring - performed on carcasse / sides after final trim - end of the kill floor, a final inspection just prior to the chiller - load out and in - after the pre boning trim - cartoon meat assessment This is used to verify the effectiveness of carcase dressing and sanitary process (ie. that the work instructions were followed correctly)

Answer 116

Process monitoring Observations are scored by the QC team on a sheet every shift through out the plant, and a figure is reached for the shift outlining how well workers conformed with the work instruction = conformity index. **Conformity index** - is a target to be considered in determining whether a process is acceptable, marginal or unaceptable - used by DAFF to see if the abattoir is performing well or not - can compare with other abattoirs ** Defect rate ** - representative samples are examined of the product through a consistent method - classification of defects are defined and their respective tolerances - all abattoirs are looking for the same thing and can be compared - DR provides an overall picture of the hygiene condition of meat and verifies the adequacy of process controls associated with production

Answer 117

Defect rate Not every carcass/product can be checked in detail. A sample from each batch is checked in detail, and if a defect or pathology is found, the entire batch will be subject to corrective action (AQL system - acceptable quality system) Simple treand charts - Simple trend charts reveal the movement of product or process standards over time - general trends can be monitored to determine production performance - trend analysis forms a critical part of verification and the management review process. Control charts A process is controlled when there is minimal variation in the final product - upper and lower control limitis - distinguish between everyday variation and real deviation indicating a process is faulty - early warning

Answer 118

**Product integrity** The quality of being honest and having strong moral principles. Product integrity means that the product meets all legitimate safety related expectations and complies with all relevant legal and regulatory requirements. - health certificate, required for export - meat transfer certificates, required between registered establishments for export eligible product that is not yet exported.

Answer 119

Traceability is a key stone of product integrity. Traceability within the abattoir Abattoir operators are identified under the Biosecurity Act 2014 as registrable biosecurity entity (RBE) - must comply with National livestock identification system (NLIS) - each has a PIC (property identity code) - responsible to report all movements of cattle, sheep and goats to the NLIS database within 48 hours of slaughter - if animals are not slaughtered within five days of arrival they must be transferred to the PIC of the facility - traceability contnues inside the abattoir once the carcase is broken down through correlation Correlation once slaughtered Animals are scanned for RFID body numbers are allocated to carcass tags (image) with body numbers applied to carcass and all carcass parts - body number also applied to offal cartoons RFID - body number on each pellet Therefore at stage of the chain the carcass can be linked to the NLIS number

Answer 120

**Verification** Conformation process - approved arrangement - HACCP plan, complete, accurate and in place - the abattoir and competant authority (Federal Department Agriculture must perform a range of verification activities.) **On plant Veterinarian (OPV)** A government veternarian is required to be located at an export registered abattoir verify; - animal health - animal welfare - food safety - product integrity / certification - market access outcomes - are correctly identified and delivered to comply with the occupiers (abattoir) approved arrangement.

Answer 121

The Australian Standard 4696 and export control require that the export abattoir have an approved arrangement. The arrangement clear describes how the company will meet all requirements, including issuing of compliance; - legislation - importing country requirements - sourcing of animals that were traeted humanely - GHP to ensure food is wholesome - The application of HACCP for food safety - Product integrity, product identification, segregation, and traceability practices - importing country identification The arrangement must be approved by the controlling authority (Federal department of Agriculture). One of the main roles of the OPV in the abattoir is to verify AA is being carried out exactly. - the Government has the evidence needed supplied by the OPV, to allow them to sign the health certificate.

Answer 122

The ten principles of certification 1. Only certify those matter which are within their own knowledge, can be ascertained or attested to 2. no certification which may raise a conflict of interest 3. no allow commercial, financial or other pressures to compromise their impartiality 4. Simple terms easy to understand 5. Should be certified on one piece of paper (or where not possible on sets of numbered sheets with a record retained by the issuing person) 6. Only sign in a launguage they understand 7. Only sign original certificates 8. Not use terms or phrases which are subject to more than one interpretation 9. Clear identification of subjects for certification 10. Signature should be ilegible, name, qualifications, address and official practice stamp + date (No deletions or alterations may be contained)

Answer 123

Audit All aspects of the QA system are thouroughly scrutinised - evaluation of corrective measures - company with non conforming product - Regulator / Authority Department of Agriculture - review documents - allows time for changes to be implemented - assess changes made to process and address the problem at hand - assess the companys preventative measures.

Answer 124

**Accreditation** - accreditation is the formal recognition by an authoritative body of the competance to work to a specified standard. - International Organisation for Standardistaion ISO - setting body composed of representatives from various National Standards organistaions Certification A written assurance by a third party of the conformity of a product, process or service to specified requirements. - health certificate Government to Government; outlines conditions necessary before importation.

Answer 125

Auditing Part of any quality assurance program is an audit - ensures standards are meet - confidential, integrity, objectivity and independance Types of auditing First party audits - Internal audits useful for buisness to asses if it is meeting regulatory requirements - not recognised by enforcement agency Second party audit - a company provides an audit of a supllier to ensure supllier is meeting their requirements - eg mc Ds audits its supplying abattoir A third party Audit Comapny wants to conform to a recofgnised international standard. - independant auditing body / company NATA - verify company has succeeded in meeting relevant standard.

Answer 126

Aniskaris "Herring worm" colourless less than one cm **Anisakids** (Nematode larvae, a complex of parasites) cetaceans: definitive host Anisakis antigens (alive or dead) cause hypersensitivity in people - has been fatal - previous case of sea food allergy Anisakis antigens. (Pictured below a human infection with Aniskaris)

Answer 127

Aqualculture - Primary prevention Farmed fish are generally considered free of parasites (minimal risk if fed commercial pellets. - no supplementation with raw fish or trash fish - No access to wild invertebrates or pest (eg earth bottomed ponds = snails = IH = risk) - management stress, hygiene, prevention

Answer 128

Wild fish: secondary prevention Most wild caught fish probably contain parasites. Secondary preventative measures; - rapid gutting (removes 50% of the burden) - cook fish well (60 degrees two mins) - slice fish fine < 1.5cm ( when grilled thin fillets are less likely to be undercooks - eviscerate and freeze ASAP - Hot smoking - Prolonged heavy curing kills most parasites (brine * 10 days, salting, pickling or smoking may no kill Diphyllobothrium.

Answer 129

Human symptoms of infection with **Anisakids** - complex of related parasites, larval nematodes - some penetrate GIT mucosa self limiting gastritis - vomiting and pain 4-6 hrs - varying severity ** D latum, Diphyllobothrium** - Largest tapeworm to infect people 3m - adult worm lives in gut of mammals - chronic debiliatation and pernicious anemia - (Vit B12) - nausea abdominal pain and weakness - largest burdens in large predatory fish Oriental SE Asian liver flukes - small ponds and paddy field - intermediate host snails - hepatic necrosis, cirrhosis

Answer 130

Seafood allergens Among the most severe of food allergies - rapid onset severe anaphylaxis Usually different fin fish and shell fish Parvalbumin in fish Tropomyosin in shell fish as well as other alergens 12 allergens all up recognised by the WHO

Answer 131

**Scombroid tuna (histamine)** - most common cause of fish related poisoning - 1000 higher levels of hsitamine within 12 hrs - temp >16 = bacterial growth and conversion of histidine to histaminephosphate in muscle protein, toxin is heat stable - symptoms usually self limiting 10-30 mins but can be prolonged - throbbing headache, weakness, skin flushing, abdominal cramps Ciguatera (Reef fish) heat stable making cooking ineffective - dinoflagellates produce, bioaccumulates in flesh and goes up the food chain - tropics - nausea followed by CNS symptoms - headaches, muscle aches, paraesthesia, ataxia - symptoms can last upto 20 years - do not consume tropical fish above 3kg

Answer 132

Bi valves Bi valves are filter feeders and can consume any environmental contamination sewage, discharge, proximity to effluent, industry and urban areas. - the water they grwo in may be polluted - filtering can concentrate the pathogens and bioaccumulate toxins from contaminated waters. - cooking is not effective against toxins Reducing the risk **Relay** - physically move harvest size shellfish to clean approved areas prior to human consumption **Depuration** Place bivalves in a controlled environment - filter themselves clean of offending organism - shellfish mus not be stressed and must ventilate / filter as normal - if stressed they will close and stop filtering

Answer 133

Shell fish toxins produced by phytoplankton, accumulate in filter feeding molluscs - generally heat stable DST Diarrhoeic shellfish toxin - nausea abdominal cramps PST Paralytic shellfish toxin - numbness of fingertips, lips, tongue, impaired muscle function

VPH Flashcards

Veterinary public health (163 cards)