MEAT HYGIENE

MEAT INSPECTION PROCEDURES

The objectives of meat inspection programme are twofold:

To ensure that only apparently healthy, physiologically normal animals are slaughtered for human consumption and that abnormal animals are separated and dealt with accordingly.
To ensure that meat from animals is free from disease, wholesome and of no risk to human health.

These objectives are achieved by antemortem and postmortem inspection procedures and by hygienic dressing with minimum contamination. Whenever appropriate the Hazard Analysis Critical Control Point (HACCP) principles should be used: The inspection procedures should be appropriate to the spectrum and prevalence of diseases and defects present in the particular class of livestock being inspected using the principles of risk assessment.

ANTEMORTEM AND POST MORTEM INSPECTION OF FOOD ANIMALS GENERAL PRINCIPLES

Antemortem Inspection

Some of the major objectives of antemortem inspection are as follows:

to screen all animals destined to slaughter.
to ensure that animals are properly rested and that proper clinical information, which will assist in the disease diagnosis and judgement, is obtained.
to reduce contamination on the killing floor by separating the dirty animals and condemning the diseased animals if required by regulation.
to ensure that injured animals or those with pain and suffering receive emergency slaughter and that animals are treated humanely.
to identify reportable animal diseases to prevent killing floor contamination.
to identify sick animals and those treated with antibiotics, chemotherapeutic agents, insecticides and pesticides.
to require and ensure the cleaning and disinfection of trucks used to transport livestock.

Both sides of an animal should be examined at rest and in motion. Antemortem examination should be done within 24 hours of slaughter and repeated if slaughter has been delayed over a day.
Spread hogs and animals affected with extensive bruising or fractures require emergency slaughter. Animals showing clinical signs of disease should be held for veterinary examination and judgement. They are treated as “suspects” and should be segregated from the healthy animals. The disease and management history should be recorded and reported on an A/M inspection card. Other information should include:

Owner's name
The number of animals in the lot and arrival time
Species and sex of the animal
The time and date of antemortem inspection
Clinical signs and body temperature if relevant
Reason why the animal was held
Signature of inspector

Antemortem inspection should be carried out in adequate lighting where the animals can be observed both collectively and individually at rest and motion. The general behaviour of animals should be observed, as well as their nutritional status, cleanliness, signs of diseases and abnormalities. Some of the abnormalities which are checked on antemortem examination include:

Abnormalities in respiration
Abnormalities in behaviour
Abnormalities in gait
Abnormalities in posture
Abnormalities in structure and conformation
Abnormal discharges or protrusions from body openings
Abnormal colour
Abnormal odour

Abnormalities in respiration commonly refer to frequency of respiration. If the breathing pattern is different from normal the animal should be segregated as a suspect.
Abnormalities in behaviour are manifested by one or more of the following signs:
The animal may be:

walking in circles or show an abnormal gait or posture
pushing its head against a wall
charging at various objects and acting aggressively
showing a dull and anxious expression in the eyes

An abnormal gait in an animal is associated with pain in the legs, chest or abdomen or is an indication of nervous disease.
Abnormal posture in an animal is observed as tucked up abdomen or the animal may stand with an extended head and stretched out feet. The animal may also be laying and have its head turned along its side. When it is unable to rise, it is often called a “downer”. Downer animals should be handled with caution in order to prevent further suffering.
Abnormalities in structure (conformation) are manifested by:

swellings (abscesses) seen commonly in swine
enlarged joints
umbilical swelling (hernia or omphalophlebitis)
enlarged sensitive udder indicative of mastitis
enlarged jaw (“lumpy jaw”)
bloated abdomen

Some examples of abnormal discharges or protrusions from the body are:

discharges from the nose, excessive saliva from the mouth, afterbirth
protruding from the vulva, intestine
protruding from the rectum (prolapsed rectum) or uterus
protruding from the vagina (prolapsed uterus)
growths on the eye and bloody diarrhoea

Abnormal colour such as black areas on horses and swine, red areas on light coloured skin (inflammation), dark blue areas on the skin or udder (gangrene).
An abnormal odour is difficult to detect on routine A/M examination. The odour of an abscess, a medicinal odour, stinkweed odour or an acetone odour of ketosis may be observed.
Since many abattoirs in developing countries have not accommodation station or yards for animals, Inspector's antemortem judgement must be performed at the admission of slaughter animals.

Postmortem inspection

Routine postmortem examination of a carcass should be carried out as soon as possible after the completion of dressing in order to detect any abnormalities so that products only conditionally fit for human consumption are not passed as food. All organs and carcass portions should be kept together and correlated for inspection before they are removed from the slaughter floor.
Postmortem inspection should provide necessary information for the scientific evaluation of pathological lesions pertinent to the wholesomeness of meat. Professional and technical knowledge must be fully utilized by:

viewing, incision, palpation and olfaction techniques.
classifying the lesions into one of two major categories - acute or chronic.
establishing whether the condition is localized or generalized, and the extent of systemic changes in other organs or tissues.
determing the significance of primary and systemic pathological lesions and their relevance to major organs and systems, particularly the liver, kidneys, heart, spleen and lymphatic system.
coordinating all the components of antemortem and postmortem findings to make a final diagnosis.
submitting the samples to the laboratory for diagnostic support, if abattoir has holding and refrigeration facilities for carcasses under detention.

Carcass judgement

Trimming or condemnation may involve:

Any portion of a carcass or a carcass that is abnormal or diseased.
Any portion of a carcass or a carcass affected with a condition that may present a hazard to human health.
Any portion of a carcass or a carcass that may be repulsive to the consumer.

Localized versus generalized conditions

It is important to differentiate between a localized or a generalized condition in the judgement of an animal carcass. In a localized condition, a lesion is restricted by the animal defense mechanisms to a certain area or organ. Systemic changes associated with a localized condition may also occur. Example: jaundice caused by liver infection or toxaemia following pyometra (abscess in the uterus).
In a generalized condition, the animal's defense mechanisms are unable to stop the spread of the disease process by way of the circulatory or lymphatic systems. The lymph nodes of the carcass should be examined if pathological lesions are generalized. Some of the signs of a generalized disease are:

Generalized inflammation of lymph nodes including the lymph nodes of the head, viscera and/or the lymph nodes of the carcass
Inflammation of joints
Lesions in different organs including liver, spleen kidneys and heart
The presence of multiple abscesses in different portions of the carcass including the spine of ruminants

Generalized lesions usually require more severe judgement than localized lesions.

Acute versus chronic conditions

Acute conditions
An acute condition implies that a lesion has developed over a period of some days, whereas a chronic condition implies the development of lesions over a period of some weeks, months or years. A subacute condition refers to a time period between an acute and chronic condition.
The acute stage is manifested by inflammation of different organs or tissues, enlarged haemorrhagic lymph nodes and often by petechial haemorrhage of the mucosal and serous membranes and different organs such as heart, kidney and liver. An acute stage parallels with the generalized disease complex, when an acute infection tends to overcome the animal's immune system and becomes generalized.
Each case showing systemic lesions should be assessed individually taking into account the significance that these lesions have towards major organ systems, especially the liver, kidneys, heart, spleen and lymphatic system as well as the general condition of the carcass.

Chronic conditions
In a chronic condition, inflammation associated with congestion is replaced by adhesions, necrotic and fibrotic tissue or abscesses. The judgement in the chronic stage is less severe and frequently the removal of affected portions is required without the condemnation of the carcass. However, judgement on the animal or carcass judgement tends to be more complicated in subchronic and sometimes in peracute stages. If generalized necrotic tissue is associated with previous infection, carcass must be condemned.

GUIDELINES FOR MINIMUM POSTMORTEM INSPECTION REQUIREMENTS (CATTLE, HORSES, SHEEP & GOATS, PIGS AND GAME)

HEADS

General View external surfaces. For cattle, horses, pigs and game view the oral and nasal cavities.

Lymph nodes (Fig. 1)
Submaxillary	Incise(a)
Parotid	Incise(a)
Retropharyngeal	Incise(a)

View and incise by multiple incision or slicing.

Heard lymph nodes

Fig. 1 : Head inspection. Retropharyngeal (No. 1), parotid (No. 2) and submaxillary (No. 3) lymph nodes are viewed and incised by multiple incisions and slicing.

Tongue

Fig. 2: Head inspection in buffalo.
Retropharyngeal lymph nodes (No. 1) are viewed and incised by multiple incisions and slicing.
Tongue View and palpate (view only in calves up to 6 weeks of age).

Other
Cattle - except in calves up to six week of age, the oesophagus of all cattle and calves should be separated from its attachment to the trachea and viewed.
- as part of inspection of all cattle and calves over the age of 6 weeks for Cysticercus bovis, the muscles of mastication should be viewed and one or more linear incisions made parallel to the lower jaw into the external and internal muscles of mastication; in addition one incision into M.triceps brachii, 5 cm behind the elbow, should be made.

Horse - the head should be split lengthwise in the medial line and the nasal septum removed and examined in all horses that are from areas where glanders is endemic.

Pigs - where there is a risk of Cysticercus cellulosae being present, the outer muscles of mastication, the abdominal and diaphragmatic muscles and the root of the tongue of all pigs should be incised and the blade of the tongue viewed and palpated;

Game - inspection cuts for tapeworm cysts are not necessary, as these cysts are generally not infective for humans.
NOTES

These are guidelines for inspection requirements, the inspection can be made more intensive or less intensive depending on the outcome of the examination.
“incise” means multiple incisions or slicing.
“palpate” as used above means to view and palpate.

GUIDELINES FOR MINIMUM POSTMORTEM INSPECTION REQUIREMENTS (CATTLE, HORSES, SHEEP & GOATS, PIGS AND GAME)

VISCERA
Lungs (Fig. 3)
View and palpate. Except in sheep and goats, the bronchi should be opened up by a transverse incision across the diaphragmatic lobes. For horses and cattle, the larynx, trachea and main bronchi should be opened along their length.
Lymph nodes
Bronchial (tracheobronchial) and mediastinal: Incise, (a) (see “Notes”)

Lungs

Fig. 3: Lung inspection - Bronchial left (No. 1) and right (No. 2) and mediastinal (No. 3) lymph nodes are viewed and incised.

Lungs

Fig. 4: Lung inspection in buffalo - Open trachea and incised bronchial and mediastinal lymph nodes.
Heart (Fig. 5)
View after the removal of the pericardium. Additional inspection requirements for cattle as per (b).
Additional inspection requirements for pigs as per (c).

Heart

Fig. 5: Heart inspection - Lengthwise incisions (minimum four) from base to apex into the heart muscles. Observe cut surfaces.
Liver (Fig. 6)
View and palpate entire surface(both sides). View the gall bladder. For cattle over 6 weeks of age, incise as deemed appropriate to detect liver flukes. Open large bile ducts. For sheep, pigs and game, incise as deemed appropriate for parasite.
Lymph nodes
Portal (hepatic), view and incise

Liver

Fig. 6: Liver inspection - Incised portal (hepatic) lymph nodes (No. 1) and opened large bile duct (No. 2).
Spleen (Fig. 7)
Palpate

Spleen

Fig. 7: Stomachs and spleen inspection - Viewing of rumen and viewing and palpation of spleen.
Gastrointestinal tract (Fig. 8)
View (a)
Mesenteric lymph nodes (Fig. 9), View (a,d)

Gastrointestinal tract

Fig. 8: Viewing of rumen, reticulum, omasum and abomasum.

Green offal fig.9

Fig. 9: Viewing and incision of the mesenteric lymph nodes. In this case an incision was performed to demonstrate the mesenteric lymph nodes chain.
Kidneys
View after enucleation. In grey and white horses - Incise.
Uterus (adults), View
NOTES

These are guidelines for inspection requirements, the inspection can be made more intensive or less intensive depending on the outcome of the examination.
“incise” means multiple incisions or slicing.
“palpate” as used above means to view and palpate.
(a) view only in calves up to 6 weeks of age.
(b) the heart of all cattle and calves over the age of 6 weeks should be inspected for Cysticercus bovis either by making one or more incisions from base to apex or by everting the heart and making shallow incisions that enable the cardiac valves and muscle tissue to be inspected; this inspection of the heart should also be undertaken in calves up to 6 weeks of age that are from areas where Cysticercus bovis is endemic.
(c) the heart of all pigs derived from areas where there is a risk of Cysticercus cellulosae being present, should be opened up and the deep incision made into the septum.
(d) incise if any lesion were observed in the submaxillary lymph nodes.

GUIDELINES FOR MINIMUM POSTMORTEM INSPECTION REQUIREMENTS (CATTLE, HORSES, SHEEP & GOATS, PIGS AND GAME)

CARCASS
General
Examine carcasses (including musculature, exposed bones, joints, tendon sheaths etc.) to determine any signs of disease or defect. Attention should be paid to bodily condition, efficiency of bleeding, colour, condition of serous membranes (pleura and peritoneum), cleanliness and presence of any unusual odours.

Lymph nodes
Superficial inguinal (male) (Fig. 10) - Palpate Supramammary (female) - Palpate (a) External and internal iliac (Fig. 10, Fig. 11) - Palpate (b) Prepectoral (Fig. 12) - Palpate Popliteal (Fig. 13) - Palpate (only sheep/goats and game/antelope) Renal (Fig. 12) - Palpate (cattle, horses, pigs) or incise if diseases is suspected. Prescapular (Fig. 14) & prefemoral - Palpate (only sheep and goats)

In all animals in which systemic or generalized disease is suspected, in all animals positive to a diagnostic test for tuberculosis, in all animals in which lesions suggestive of tuberculosis are found at postmortem inspection, the main carcass lymph nodes being the precrural, popliteal, anal, superficial inguinal, ischiatic, internal and external iliac, lumber, renal, sternal, prepectoral, prescapular and atlantal nodes, as well as the lymph nodes of the head and viscera, should be incised and examined.

Other
The muscles and the lymph nodes (lymphonodi sub-rhomboidei) beneath one of the two scapular cartilages of all grey or white horses should be examined for melanosis after loosening the attachment of one shoulder.
NOTES

These are guidelines for inspection requirements, the inspection can be made more intensive or less intensive depending on the outcome of the examination.
“incise” means multiple incisions or slicing.
“palpate” as used above means to view and palpate.
(a) incise when udder is or has been in lactation or in case of mastitis.
(b) means iliac nodes in pigs.

Bovine carcass fig.10

Fig. 10: Superficial inguinal and internal and external iliac lymph nodes in a pig. Viewed and palpated on routine P/M examination.

Bovine carcass fig.12

Fig. 11: Medial view of the hind quarter. Superficial inguinal, internal and external iliac and lumbar lymph nodes are palpated and incised in systemic or generalized disease.

Bovine carcass fig.13

Fig. 12: Medial view of the fore quarter with intercostal, suprasternal, presternal and prepectoral lymph nodes. Presternal and prepectoral lymph nodes are incised.
Fig. 13: Popliteal lymph nodes in a pig. These nodes are incised if a systemic or general disease is suspected.

Bovine carcass fig.14

Fig. 14: Lateral view of the carcass. Precrural and prescapular lymph nodes are incised in systemic or generalized disease.

Bovine lympthnodes

Fig. 15: Medial view of carcass with relevant lymph nodes

ANTEMORTEM AND POSTMORTEM INSPECTION OF POULTRY

Antemortem inspection of birds presents some difficulties if the birds are placed in crates or liners, and hence only a superficial inspection of their general condition is carried out. The remainder of the poultry examination should take place after the birds have been hung in shackles and before they are bled. The records of antemortem inspection are mandatory and should include date and time of inspection, truck number, species, the total number of birds and the name of the owner. The objectives of antemortem examination are:

to determine the general condition of the birds
to establish if a disease or condition requires particular handling such as segregation of diseased birds, delayed slaughter or adjustment of line speed.

In inclement weather, particular in winter, birds require immediate slaughter. In the summer, the steady change of air in the truck or in the holding area should be maintained. In cases of reportable disease, such as avian influenza or Newcastle disease, a veterinarian should be informed and all pertinent information should be recorded. Some diseases have similar signs on A/M inspection. For example, infectious bronchitis may be confused with Newcastle disease. A differential diagnosis is required in such cases.

Postmortem inspection in poultry refers to inspection techniques and inspection of carcasses and viscera. P/M examination consist of viewing, palpation and smell. The colour, shape, and consistency of organs and tissues must be observed singly or in combination. The colour of the poultry carcass depends on age, sex, nutrition and the scalding temperature during slaughter.

Carcasses must be suspended at 2 or 3 points depending on the class of poultry. Intestinal tract, liver, spleen, and heart (viscera) must be exposed for visual examination and palpation. A poultry inspector (Fig. 16) should be able to look inside the carcass and detect any pathological lesions such as airsac inflammation, peritonitis, oviduct inflammation (salpingitis) etc. Contamination by faeces and bile should also be observed. During the examination of viscera and carcass, both hands should be used. External lesions on the carcass include the swelling of the sinuses, nasal and ocular discharge (if the head is present), skin lesions, joint swellings etc.

Judgement : Localized lesions could be disposed by an inspector, however the final judgement of the carcass should be done by a veterinarian. The condemnation of carcass is usually for pathological, non pathological and aesthetic reasons.

Poultry inspection

Fig. 16: Inspection of the viscera and carcass in a broiler.

SLAUGHTER AND INSPECTION OF GAME ANIMALS FOR MEAT

Some parts of the world continue to be blessed with large, thriving populations of game animals, in Africa particularly antelopes such as impala, kudu and eland, in the Southern part of Latin America hares and some deer and antelope species and in Eastern Europe red and roe deer. Controlled cropping of these herds can provide a significant, sustainable source of supplementary protein especially in rural areas.
In ideal circumstances and in case of the game meat is for export, two basic systems of culling and carcass preparation can be used.

The first system is one of night shooting on foot using spotlights. Animals which appear healthy are shot, immediately bled and the stomachs and intestine eviscerated on the spot. After a number of carcasses have been collected on an accompanying vehicle, they are then transferred to a central, permanent abattoir facility suitable for their dressing, inspection and refrigeration. Since antemortem inspection is performed by hunters, they should be trained in basic antemortem procedures in order that they may be able to select healthy from sick animals.
In the second system animals are rounded up and herded into a temporary, funnel like structure. The animals are rested and antemortem inspection is carried out much more objectively. Animals are then shot at point blank range, bled and eviscerated immediately and removed to a temporary butchery for dressing, inspection and refrigeration. Ante and postmortem inspection can be objectively carried out with this system, although hygiene could be somewhat compromised. A judicious combination of features form both these systems, which can be modified, can be used to suit a variety of circumstances in the field.

Antemortem and postmortem inspection procedures
The inspection procedures that are most appropriate to any particular type of game animal or carcass will vary not only according to species, but also according to whatever other information may be available about the wildlife population from which they are harvested. Minimum inspection procedures as set out in the Joint FAO/WHO Codex Alimentarius Commission's Code of Hygienic Practice for Game, are useful commencing points in developing appropriate procedures.

Judgement categories
The decision at inspection is classed into the following categories of Judgement:

Approved as fit for human consumption.
When the inspection and any other information available has revealed no evidence of any unacceptable disease or defect, and if the dressing has been implemented in accordance with hygienic requirements, the game carcass and offal should be approved as fit for human consumption without restriction provided no animal health restrictions are otherwise applicable.
Totally unfit for human consumption.
The game animal and all offal should be condemned or otherwise disposed of for inedible purposes if:

they are hazardous for food handlers, consumers and other animals;
they show decomposition, extensive injury, swelling edema, emaciation or contamination;
they show signs consistent with natural death, death by trapping or a moribund state.
there are unacceptable deviations, form normal game meat, detectable by sensory means.

3. Partially condemned.
Where lesions are localized, affecting only part of the carcass or offal, the affected parts should be removed and the unaffected parts conditionally or unconditionally passed.

Conditions affecting antelope
The antelope is perhaps the most preferred and frequently hunted species of game animal in Africa for the specific purpose of providing meat for human consumption. The impala is the easiest of the antelope to cull on a large scale, although the eland is almost as easy to manage as some domestic cattle. Favourable features of antelope are their apparent good herd-health and lack of pathological and parasitic conditions found at meat inspection. Causes of condemnation of the carcass, meat and offal in impala in Africa seem to fall into two categories:

Management related
Disease related

Management related:
trauma - due to gunshot wounds.
contamination - chiefly gross dirt attained from the environment during bleeding and de-gutting or intestinal contents during careless evisceration.
spoilage and putrefaction - wastage for these reasons can be considerable in Africa if operations are carried out during summer daytime. These losses can be minimized if hunting and dressing are done during the winter months, at night and during lower ambient temperatures.
Disease related:
Parasites
“measles” - tapeworm cysts of various kinds have been found in game carcass such as impala, kudu, bushbuck, reedbuck, sable, wildebeest (gnu, antelope) and warthogs. The cysts vary in size from that of a pea to a golf ball and are often seen in the peritoneal cavity, loosely attached to the serosa, viscera or in the musculature. There are no special predilection sites of the muscular cysts. Routine inspection incisions for measles in domestic animals are of no value in determining presence or degree of infestation in game animals. Serosal affection can be successfully trimmed before release but muscular parasites make the carcass aesthetically unacceptable. In the latter carcass can be boiled or used for manufacturing purposes. These cysts do not seem to affect humans.

Sarcocysts - these are frequently seen in the skeletal muscle of impala (mostly microscopic however); the carcass may have to be condemned if severely affected.

Stilesia - this tapeworm may be found in the liver of small antelope and seem to be widespread in Africa. Trimming is required.

Cooperoides hepatica - this is a small brown filarial worm which occurs coiled up in a cyst in the liver, most frequently in impala. It is often associated with stilesia. Trimming is required.

Cordophillus - a filarial worm found encysted in the heart muscle of kudu. 25% of these animals are affected. This parasite is occasionally found in other muscle and may also occur in the heart muscle of domestic cattle. Affected tissue should be trimmed.

Hydatid - these cysts have been seen in the lungs and livers of impala, zebra, giraffe and warthog. If slight infestation is present affected tissue should be trimmed.

Pathological conditions - the incidence of septicemic/bacteremic conditions and pneumonia were extremely low.

SLAUGHTER AND INSPECTION OF FARMED GAME

Red deer and fallow deer and some of the antelopes mentioned above are the main species which are farmed for meat production. In particular in New Zealand, but also in Europe and some other regions game farming has become an important source of supplying the domestic and export markets with venison.

Farmed game is in many cases slaughtered in special premises and is therefore subject to antemortem and postmortem inspection. Game farmers are now experienced enough to arrange for live animal transports on trucks to the game slaughterhouses. These abattoirs have specific lairages, where the animals can be rested. Slaughter takes place by using captive bolt pistols for stunning and bleeding, deboning evisceration and carcass dressing is similar to cattle slaughter, however carcass splitting is usually not performed.

Antemortem and postmortem inspection procedures and conditions affecting the farmed game are similar to the situation described for wild game. However, residues in meat (veterinary drugs, pesticides), parasitic diseases or infectious diseases such as tuberculosis may pose major problems than it is the case in wild game.

SLAUGHTER AND INSPECTION OF OSTRICHES

The slaughter of farm ostriches is fast becoming a commercial enterprise and may provide an important source of lean, high-protein meat for human consumption. The slaughter and dressing procedures consist essentially of stunning, bleeding defeathering and dressing. These operations are carried out in separate rooms.

- Stunning. The bird is stunned electrically using 90 volts at 1.5 amperes for approximately 20 seconds.
- Bleeding. The neck and vessels are severed behind the jaw.
- De-feathering. This is done manually in order to avoid damage to the skin follicles.
- Dressing is done in a manner similar to that of small ruminants. Organs are eviscerated in one set.

Antemortem inspection :
The following are characteristics of apparently healthy ostriches:

Alert and inquisitive with a bright eye and erected neck; occasionally lowering and then raising head.
Walks with a springy gait and may sometimes be aggressive.
Pecks inquisitively at shiny objects.
Produces thick, white clear urine and firm faeces.
The feathers are fluffed up and the body appears well rounded. The tail is well perked.

The following are characteristics of sick ostriches:

Lethargic and drooping neck and wings. It may sit down frequently or become recumbent. This clinical sign may also be observed in the stressed bird.
The eyes are half closed
The mucosa of the mouth may be very congested; the ostriches peck at food but do not swallow.
The abdomen may sometimes be bloated and blue/purple.
The urine may be green or brown and the faeces fluid or pasty.
The feathers appear bedraggled; the wings and tail drop.

Postmortem inspection:
It will be necessary for the head, pluck (heart, pericardium, liver, spleen, and lung if possible), alimentary tract, genitalia and carcass (with neck and kidney) to be properly identified and presented separately for inspection. The ostrich, like other avian species is lacking an organized lymphatic system. Since many viral and bacterial infections tend to be of a generalized nature, sound and professional meat inspection examination and judgement of the birds and carcass is of great importance.
Lungs not removed during dressing procedures should be examined visually and by palpation in the thorax. To expose the lungs, two cuts above the lungs on the each side of the ribs should be made.

Head
Visual examination of the mouth, palate, eyes, lips and sinuses for icterus, sinusitis, crusting of eyelids and thrush (oral Candida infection)

Pluck
Lungs - visual and palpation for haemorrhage, edema and pneumonia.
Heart - visual and palpation for haemorrhages; expose valves for endocarditis.
Pericardium - visual, and incision if necessary; for pericarditis.
Liver - visual and palpation; incise if necessary; for icterus, discolouration, adhesions, degeneration, abscess, fibrosis, inflammation and toxic conditions Spleen - visual and incision if necessary; for enlargement, haemorrhages and signs of febrile or septic conditions.
Kidney - visual and palpation; for haemorrhages, degeneration, urate crystals.

Intestinal tract
Oesophagus/proventriculus, gizzard - visual and palpation; for foreign body penetration, impaction, inflammation and ulceration and parasitic conditions (nematode-Libyostrongylus) in glands of proventriculus.
Small intestine - visual and palpation; impaction, volvulus, necrotic and catarrhal enteritis and small tapeworm (Houttynia).
Large intestine - visual and palpation for faecal impaction, stones, inflammation and nematode (Condiostomum).
Reproductive organs - visual for egg retention, rupture, prolapsed penis; Atrophic organs are found during non-breeding season.

Carcass
Visual inspection of external and internal carcass surfaces, limbs and joints. Observe for contamination, inadequate bleeding, bruising, haemorrhages, lacerations, fracture, dislocation, twisted legs, adhesions, icterus, arthritis, peritonitis, air sacculitis, abscesses (injection sites), foreign bodies.

Judgement
Carcass should be condemned if affected with any of the following: death from any cause other than slaughter, extensive bruising and haemorrhages, general contamination, putrefaction, emaciation, edema, icterus, septicemia, aspergillosis, toxoplasmosis, malignant or multiple tumours, leucosis, poisoning. The parts of the carcass which show localized lesions may be trimmed and the rest of the carcass would then be approved.

SUPERVISION OF HYGIENIC DRESSING OF CARCASSES

1. During dressing the carcass is exposed to contamination from:

Abattoir environment including implements used, and the hands of the operators. A variety of bacteria, fungi and yeasts are in the abattoir environment. Studies in abattoirs indicate that salmonella counts in the implements used may vary from 0 – 270 per cm² or more in each implement, depending on their regular cleaning and sanitation the scabbards having the highest numbers.
Hides of the animals
Hides are heavily contaminated parts and can reach up to 3 × 10⁶ bacteria per cm² or more.
Stomach and gastrointestinal contents
Gastrointestinal contents have the heaviest load of microorganisms. Faeces contain up to 9.0 × 10⁷ bacteria per gram, and various numbers of yeast and mould. The ruminal contents have only slightly lower numbers of micro-organisms.

2. Therefore, during meat inspection it is an important duty of the inspecting officer to ensure that:

the implements used during slaughtering, dressing and meat inspection are well sanitised periodically or whenever they are likely to be contaminated;
during cutting into the hide and exposure of the carcass, the external surface of the hide does not contact the carcass meat;
the viscera are not accidentally opened during the dressing procedures or during evisceration.

3. If a carcass or part is contaminated with faeces or visceral contents such areas should be trimmed off. The opened viscera would have to be separated from the rest of the carcass as quickly as possible.
4. The introduction of a Hazard Analysis Critical Control Point (HACCP) concept can be helpful to maintain high standards of slaughter and dressing hygiene based on an assessment of the risks to human and animal health.

HAZARD ANALYSIS CRITICAL CONTROL POINT (HACCP) CONCEPT IN MEAT INSPECTION

A specific HACCP concept tailored to each abattoir and the class of animal should be developed to ensure the most efficient and effective concept of sanitary control.
The introduction of specific HACCP concept involves the following:

identifying hygienic hazards
ranking these hazards
defining the critical limit
identifying the critical control points
recommending necessary control
record keeping
verification procedures to ensure efficiency
tests to ensure that the concept is working

The Hazard Analysis Critical Control Point (HACCP) Concept was introduced in the food industry in 1971 to ensure that there would be effective control of the quality of processed foods. The World Health Organization (WHO) recommends that this concept also be applied to Meat Inspection and Meat Hygiene in particular to control salmonellosis. It can also be used to reduce bacterial contamination during slaughtering and dressing and to ensure quality control in Meat Inspection.

Meat Inspection and Meat Hygiene shall make sure that meat and meat products are safe and wholesome for human consumption. The practise of meat inspection has gradually changed over the last three decades. The classical antemortem and postmortem procedures were designed to detect disease in an animal before slaughter and the lesions produced by the disease after slaughter respectively. This was done by the use of senses (organoleptic tests) such as the use of touch (palpation), sight (inspection and observation), smell (gangrenous smell) and taste (only in cooked products). Zoonotic diseases, particularly tuberculosis received high priority. Laboratory tests were done to confirm the disease when necessary or as appropriate.

With the gradual reduction in the incidence of animal tuberculosis in many countries along with the development of intensive methods of animal husbandry and the widespread use of pesticides and veterinary drugs, new problems are emerging. These are associated with residues on one hand and increased human infections with zoonotic agents contaminating animal foods on the other. There appears to be a general trend worldwide, with a few exceptions where human Salmonella infections have nearly doubled during the last five year period and human Campylobacter infections have nearly tripled during the same period.

Other bacteria that are causing increasing concern as food contaminants are Yersinia spp. and Listeria spp. There is simultaneously a greater consumer expectation of a longer shelf life in the finished fresh meat product. All these factors suggest that in the practise of meat inspection, it would be advantageous to use the HACCP concept to identify the critical control points at which these bacterial groups and other spoilage organisms may contaminate the carcasses, so that appropriate action can be taken. The critical control points that have been identified for Salmonella contamination in red meats, and poultry are shown in Fig. 17 and Fig. 18. These are applicable to other major bacterial contaminants as well.

These figures show that during red meat production, major contamination occurs in the abattoir during skinning and evisceration, that some contamination could occur during transport, lairage and deboning and that the most effective control point is in the chiller. Therefore, it is absolutely essential for meat inspectors to ensure that skinning and evisceration are done properly. The critical control points during the slaughter of poultry (Fig. 18) are picking and evisceration. In developing countries where these tasks are not automated, it is necessary to ensure that proper hygienic precautions are taken during each of these operations. In automated plants, the machinery for picking and evisceration would need to be sanitised regularly, in particular when birds from different sources are slaughtered.

Fig. 17: Flow diagram showing sources of contamination with Salmonella and Critical Control Points (CCP) in Red Meat Production.

Source of contamination

Fig.18: Flow digram showing sources of contamination with Salmonella and CCP in processing of Poultry Meat.


Source of contamination