Red meat inspection and gross pathology

Question 1

List the statutory meat inspection protocols

Answer 1

Visual
Palpation
Incision
Variable with species and age
ex. Pigs & bovines <8 month: Visual inspection by default

Question 2

Describe meat inspection in bovine >8mo, of the head, tongue and throat

Answer 2

• Incision and examination of the retropharyngeal lymph nodes, external masseters, 2 parallel incisions to the mandible, and the internal masseters
• When there are indications of a possible risk to human health, animal health or animal welfare: Incision and examination of the sub-maxillary and parotid lymph nodes; palpation of the tongue and fauces

Question 3

Describe meat inspection in bovine >8mo, of the trachea, oesophagus and lungs

Answer 3

• Incision and examination of the bronchial and mediastinal lymph nodes, palpation of lungs
• When there are indications of a possible risk to human health, animal health or animal welfare: Incision of the bronchial and mediastinal lymph nodes; lengthwise opening of the trachea and the main branches of the bronchi; the lungs shall be incised in their posterior third, perpendicular to their main axes if lungs for human consumption

Question 4

Describe meat inspection in bovine >8mo, of the pericardium and heart

Answer 4

Only when there are indications of a possible risk to human health, animal health or animal welfare
- Lengthways incision of the heart so as to open the ventricles and cut through the interventricular septum

Question 5

Describe meat inspection in bovine >8mo, of the liver and the hepatic and pancreatic lymph nodes

Answer 5

Only when there are indications of a possible risk to human health, animal health or animal welfare
- Palpation of the liver and the hepatic and pancreatic lymph nodes (Lnn. portales); incision of the gastric surface of the liver and at the base of the caudate lobe to examine the bile ducts

Question 6

Describe meat inspection in bovine >8mo, of the gastro-intestinal tract, the mesentery, the gastric and mesenteric lymph nodes

Answer 6

+ palpation of the gastric and mesenteric lymph nodes
When there are indications of a possible risk to human health, animal health or animal welfare: incision of the gastric and mesenteric lymph nodes

Question 7

Describe meat inspection in bovine >8mo, of the udder and its lymph nodes

Answer 7

Only hen there are indications of a possible risk to human health, animal health or animal welfare
- A palpation and incision of the udder and its lymph nodes (Lnn. supramammarii) in cows.
- Each half of the udder shall be opened by a long, deep incision as far as the lactiferous sinuses (sinus lactiferes) and the lymph nodes of the udder shall be incised, except where the udder is excluded from

Question 8

Instead of testing a pork carcass for Trichinella what can be done?

Answer 8

Freezing the carcass
Minimum core temp -18 when treated for 106 hours
Minimum core temp of -37 when treated for 30 mins

Question 9

How does Trichinella spiralis infection occur?

Answer 9

Zoonotic:
- Infection by consumption of undercooked meat
- Life-threatening to mild symptoms in 5-20 days
- More noticeable when outbreak

Question 10

Case: Epulides seen in the mouth
What action would be taken?

Answer 10

• Wont affect what happens to the carcass in this case
• But shows welfare implications -> farm serious breech

Question 11

OV will declare meat unfit for human consumption if it derives from animals slaughtered under the age of …?

Answer 11

7 days

Question 12

The meat fitness decisions are made based on which factors?

Answer 12

• Zoonotic infection if ingested?
• Zoonotic risk but not by consumption of presented product?
• Systemic process: Immunosuppression etc
  No zoonotic risk but:
• Prevention of animal disease spread (ex. FMD)
• Meat quality (ex. Traumatic lesions)
• Aesthetics (ex. Cysticercus ovis)

Question 13

List some generalised conditions which are considered unfit for human consumption

Answer 13

Septicaemia
Pyaemia
Jaundice
Emaciation
Toxaemia
Viraemia
Malignant tumours

Question 14

How can a carcass be tested for ‘fit for human consumption’ if it has toxaemia?

Answer 14

Hold carcase for 24 hours and check by boiling/frying test
Unfit for human consumption if smell still present

Question 15

Name an example Viraemia that would be considered unfit for human consumption

Answer 15

BVD: Bovine pestivirus
- Sx: ulceration oesophagus, base of tongue and soft palate
- Disease: Bovine virus diarrhoea / mucosal disease
- Most common in young cattle (6-24 mo old)

Question 16

When is neoplasia not fit for human consumption?

Answer 16

When its malignant

Question 17

Melanosis discoloration is disposed of as?

Answer 17

Category 3 ABP

Question 18

What is the most common malignancy in cattle?

Answer 18

Sporadic Bovine Lymphosarcoma

Question 19

How does Sporadic Bovine Lymphosarcoma present?

Answer 19

The cause is not known
It occurs in young cattle between 6 months and 2 years of age
There are two forms :
- Multicentric = In which all the lymph nodes are massively enlarged and replaced by white homogenous tumour tissue
- Thymic lymphosarcoma = In which there is a large swelling in both the cardiac and cervical parts of the thymus

Question 20

What happens to a carcass with sporadic bovine lymphoma?

Answer 20

Unfit for human consumption

Question 21

Name a zoonotic condition of pigs where changes are seen due to necrosis/infarction

Answer 21

Erysipelothrix rhusiopathiae

Question 22

How does the level of disease of Erysipelothrix rhusiopathiae influence the action taken on the carcass?

Answer 22

1. Mild type - Diamonds visible on skin. Possible bacteraemia. Judgement: depending on lesions.
2. Acute or septicaemic. Judgement: total rejection.
3. Chronic: Arthritis, endocarditis, enlarged lymph nodes… Judgement: local or total rejection depending on severity and extension of the lesions.

Question 23

If a pig carcass with Erysipelothrix rhusiopathiae has endocarditis, what action is taken?

Answer 23

Rejection of carcass due to emboli spread

Question 24

What action is taken if a carcass has jaundice?

Answer 24

Unfit for human consumption
Yellow colour at the level of many tissues

Question 25

What may also cause a yellow colouration of tissues?

Answer 25

Due to feed - this carcass would be normal

Question 26

What action is taken if a carcass has septicaemia?

Answer 26

Unfit for human consumption

Question 27

What is vertebral porphyria?

Answer 27

Porphyria is the accumulation of plant or endogenous porphyrins in the blood resulting in tissue pigmentation and photosensitization.
This is a hereditary disease and is observed in cattle, swine and sheep.
In porphyric cattle, exposure to light will initiate the development of photodynamic dermatitis. In swine, photodynamic dermatitis does not occur

Question 28

What happens to a carcass with vertebral porphyria?

Answer 28

Partial rejection

Question 29

If a carcass has anaemia what action is taken?

Answer 29

Diagnosis:
- White muscle disease – selenium/vitamin E deficiency
- Also linked to mulberry heart disease
Unfit for human consumption

Question 30

What is Hydrocachexia?

Answer 30

Emaciation with serous atrophy of adipose tissue
DDX: Age related muscle atrophy

Question 31

What action is taken if a carcass has Hydrocachexia?

Answer 31

Unfit for human consumption

Question 32

What are the issues surrounding tail bites?

Answer 32

Welfare
Point of infection -> systemic spread of pathogens -> osteomyelitis

Question 33

What action is taken in a carcass with rub fractures?

Answer 33

Decision - Callus – partial rejection because it shouldn’t have a major impact on the carcass
If no evidence of septicaemia
- Decision: Partial rejection
- Depending on extent/localization of callus could imply a welfare issue at the farm of origin

Question 34

What action is taken in a carcass with calcification?

Answer 34

Partial rejection
DDx
- Abscess
- Contamination with foreign material

Question 35

What action is taken in a carcass with embolic pneumonia?

Answer 35

total rejection