PMI of poultry

Question 1

Causes of emaciation in poultry

Answer 1

○ Immuno-suppressive diseases (IBD)
○ Lymphoid diseases (Marek’s)
○ Bacterial disease (avian TB)
○ Septicaemia
○ Airsacculitis
○ Parasitic diseases
○ Parasitic diseases
○ Mixed infections (egg peritonitis)

Question 2

Judgement for contact dermatitis

Answer 2

Affected areas rejected
Could indicate welfare issues

Question 3

Judgement of septicaemia

Answer 3

Dark soft dehydrated carcase

Generalised condition may be accompanied with petechial haemorrhage in red offal and muscle

Incidence of condition is a good indication of overall health of flock

Reject whole carcase

Question 4

Joint lesions in poultry

Answer 4

Infections
○ Mycoplasma synoviae
○ Reovirus
○ Opportunistic bacteria

Trauma

Angular limb deformities
○ Growth plate trauma
○ Nutritional imbalances
○ Slipped tendon

Question 5

Green leg disease in poultry

Answer 5

• Rupture of gastrocnemius tendon
  
  • Green colouration, resolving bruise
  • Causes
    ○ Tenosynovitis
    ○ Viral or bacterial infection
    ○ Trauma
    ○ Genetic susceptibility

Question 6

Skin tumours in poultry

Answer 6

Squamous cell carcinoma
○ Crater-like lesions coalesce to form large ulcerated areas
○ Uneven or localised thinning of skin, often torn by pluckers

Marek’s disease (skin form)
○ Lymphomas of feather follicles and skin

Question 7

Dermatitis in poultry

Answer 7

Inflammation of the skin

Usually secondary infected
○ Staphylococci, streptococci, clostridia, erysipelas

Commonly presents as
○ Breast burns
○ Blisters
○ Hock burns
○ Pododermatitis
○ Scabby hip dermatitis
○ Gangrenous dermatitis (clostridium septicum infection)

Caused by contact with irritants
○ Wet litter
○ Scratches from toes of other birds

High incidence associated with poor management on farm

Question 8

Uncut or badly bled poultry

Answer 8

Possible welfare implication in stun only systems
○ Potential of live bird entering the scald tank alive

Can be due to
○ Flocks of uneven size
○ Poorly adjusted and maintained equipment
○ Failure of back-up slaughtermen
○ Bleeding times insufficient

Question 9

White muscle disease in poultry

Answer 9

White striping in the breast muscle, becomes stiffer

Vitamin E/selenium deficiency
○ Usually caused by inability to use nutrient
○ Rather than an absolute deficiency

Question 10

Congenital abnormalities in poultry

Answer 10

Polydactylia
○ Extra digits or limbs are common in poultry
○ Usually associated with mutation of the vents

Can cause problems with automated evisceration machines

Question 11

Airsacculitis in poultry

Answer 11

Inflammation of the airsacs
○ Usually accompanying lesions in the bronchi and lungs

Acute cases (less common)
○ Small haemorrhages
○ Serosanguinous exudate

Chronic lesions
○ Airsacs are thicker and opaque
○ Containing caseous material or mucopurulent exudate
○ Adhesions and fibrosis

Caused by many agents
○ Mycoplasma spp., E. Coli, aspergillosis, and avian cholera (Pasteurella multocida)

Environmental conditions predispose
○ Ammonia levels, poor ventilation, excessive stocking density, poor hygiene

A high flock incidence may be indicative of suboptimal health and welfare on the farm

Question 12

Avian tuberculosis

Answer 12

• Nodules can be found in all organs, mainly in:
  ○ Lungs
  ○ Liver
  ○ Spleen
  
  • Caused by
    ○ Mycobacterium avium
  • Chronic infection affecting older birds
  • Usually in contact with wild birds

Question 13

Pericarditis in poultry

Answer 13

Changes to pericardium
○ Increased opacity
○ Cloudy or turbid fluid in pericardial sac
○ Dense white inflammatory tissue
○ In chronic cases it becomes adhered to the heart

Bacterial infection is the most common cause with infections occurring
○ Early in life as a chick
○ During the growing period
○ E. Coli and Salmonella spp, usually following viral infection
○ Mycoplasmas have been implicated

High incidence may indicate
○ Disease problems in breeder flock
○ Poor egg hygiene
○ Poor farm hygiene
○ Presence of respiratory viruses

Question 14

Hepatitis in poultry

Answer 14

In hepatitis the liver
○ Enlarged has round edges and a smooth surface
○ Often with necrotic foci or a reticular pattern

In the acute phase
○ Liver tends to be cherry red

Chronic the liver becomes pale brown, bronze, or green

High levels in a flock may indicate
○ Feed related problems
○ Proliferation of enteric bacteria
§ Cl. Perfringens
§ Campy spp.
§ Salmonella spp.
○ Viral infections (adenovirus)

Question 15

Jaundice in poultry

Answer 15

Excess levels of bilirubin tinges body tissues yellow

This occurs less frequently in avians than in mammals
○ Bilirubin only forms 6% of bile in birds

Usually accompanied by liver disease
○ Cholangiohepatitis
○ Hepatitis
○ Cirrhosis

Can be
○ Post-hepatic (obstructive)
○ Hepatic
○ Pre-hepatic

Question 16

Peritonitis and perihepatitis in poultry

Answer 16

Peritonitis
○ Inflammation of the membranes lining the abdominal cavity and organs

Perihepatitis
○ Inflammation of the liver capsule

Often dry caseous or mucopurulent exudates in the abdominal cavity

May be secondary to previous conditions
○ Trauma
○ Salpingitis
○ Enteritis
○ Hepatitis

Commonly isolated bacteria
○ E. Coli
○ Salmonella
○ Pasteurella

Possible causes:
○ Immunosuppression caused by IBD
○ Marek’s disease
○ Respiratory disease
○ Poor farm hygiene

Question 17

Salpingitis

Answer 17

• Inflammation of the oviducts
  
  • Often with purulent material present
  • Various infectious causes:
    ○ Mycoplasma
    ○ E. Coli
    ○ Salmonella
  • Infections may spread
    ○ Infected abdomens abdominal airsacs
    ○ Ascending from cloaca
  • There may be distension of the abdomen present

Question 18

Marek’s disease

Answer 18

Marek’s disease can present in four forms
○ Ocular form - pearl eye
○ Neural form - enlargement of peripheral nerves causing paralysis
○ Skin form - lymphomas of feather follicles and skin
○ Visceral form - organ enlargement and soft grey lymphomas

Affects birds from 6 weeks
○ Caused by a herpes virus
○ Preference for peripheral nerves
○ Virus replicates in feather follicle cells

Question 19

Tumours in poultry

Answer 19

Avian leucosis
○ Similar to visceral form of Marek’s

Haemangioma
○ Benign congenital overgrowth of blood capillaries

Fibrosarcoma
○ Virus induced

Fibromyoma
○ Virus induced

Question 20

Gout

Answer 20

Abnormal deposition of uric acid in tissues
○ Associated with high protein diets

Generally affects individual birds

Possible genetic defect in uric acid metabolism

Found in 2 forms
○ Visceral gout, form of peritonitis
○ Articular gout, affects joints

Question 21

Erysipelas in poultry

Answer 21

Primarily a disease of turkeys

Affected birds listless
○ Rarely with swelling of the snood

Typical signs
○ Septicaemia
○ Liver becoming
§ Enlarged
§ Congested
§ Friable
○ Intestines congested
§ Catarrhal enteritis
○ Valvular endocarditis
§ Present in chronic cases