1) Pulmonary adenomatosis is a contagious lung cancer of sheep caused by a retrovirus that leads to proliferation of epithelial cells in the lungs. 2) Clinical signs include weakness, emaciation, coughing, nasal discharge, and difficulty breathing. Mortality can reach 100% without treatment. 3) At the microscopic level, hyperplasia and hypertrophy of lung cells is seen, forming papillary tumor masses. Diagnosis is based on clinical signs and histopathology of lung tissue. There is no treatment, so control relies on culling infected animals and disinfecting premises.

1. Pulmonary Adenomatosis
pulmonary Carcinoma
Lung cancer of sheep
By
Prof Mohamed Ghanem

2. Pulmonary Adenomatosis or
pulmonary Carcinoma
Lung cancer of sheep
Definition:
• It is a contagious neoplastic disease of sheep
characterized by continuous development of
weakness and emaciation, dyspnoea, nasal
discharge and frequent cough caused by
Onchogenic retrovirus.

3. Occurrence
1. The clinical signs appeared only in adult
animals (Neoplastic disease).
2. Goat are infrequently affected.

4. Etiology
1. Onchogenic Retrovirus of the family retrovirdae (6
classes of the virus are isolated which are A, B, C,
D, E and F).
2. The disease is transmitted by
1. respiratory secretions that contain all infected cell,
which coughed by diseased animal during coughing in
the environment then inhaled by healthy animal or
2. the infection occurs by inhalation of the virus itself.
3. overcrowding of sheep in pens especially in
closed buildings facilitates spread of infection
from diseased to healthy animals.

5. Pathogenesis
• The virus attacks the target cells which are:
• Alveolar type II epithelial cells
• Terminal non-ciliated bronchiolar epithelial cells
(Clara cells).

6. Coughing – hypoxia - dyspnoea
Cell proliferation (the virus multiplication) till occupy all the alveolar lumen
proliferation transferred to the adjacent alveoli
The peripheral neoplastic cells contain secretary granules
secrete osmophilic secretion that leads to increase the nasal discharge
cell division leads to expansion of the small foci resulting in formation of large nodules
hindrance to pulmonary circulation - right ventricular hypertrophy, cardiac failure and death.

7. Immune reaction of the animal
1. Infiltration of large numbers of alveolar
macrophages that plays a role in:
1. Engulfing microorganisms by phagocytosis.
2. Limit the metastasis of the neoplastic cells
2. Immunoglobulins are excreted from the plasma
cells (blood cells) that present in the interstitial
space.

8. Death occurs due to:
1. Severe hypoxia and dyspnoea.
2. Ventricular hypertrophy and CHF.
3. Secondary bacterial invasion

9. • Incubation period
• 2 months to 2 years
• Course; several weeks to several months
• Mortality: up to 100 %
• Morbidity: up to 20 %

10. Clinical symptoms
Depends upon the severity and stage of
disease
1. In early stage:
1. The animal appears in good healthy condition.
2. Shallow rapid respiration appears after
excitement with frequent coughing.
3. Dilation of nostrils due to dyspnoea.
4. Extension of head and neck during inspiration.
5. Auscultation reveals rales and consolidation
particularly in the ventral plane.

11. Clinical Signs
2- In late stage:
1. Weakness and emaciation.
2. Nasal and ocular discharge.
3. Dyspnoea.
4. Loss of weight despite normal appetite.
5. The animal remains in standing position
because recumbency may exacerbate the
dyspnoea
6. Death after a few months, usually associated
with secondary pasteurellosis

12. Positive wheelbarrow test
Elevation of the
hindquarters of
the affected
sheep
(wheelbarrow
test) resulting in
fluid run out of
the nostril in
severely
affected animals

13. Nasal discharge when sheep
lower the head

14. Severe emaciation

15. PM lesions
1. In early stage: the lung contains blue gray
nodules 1-20 mm diameter.
2. In late stage:
1. Lung contains small nodules with large neoplastic
mass.
2. Regional lymph nodes are enlarged from
metastasis.
3. Right ventricle is hypertrophied and dilated.
4. Small amount of exudates may excavate and
accumulate in some body cavities

16. Lung nodules

17. Histopathology
1. Hyperplasia and hypertrophy of alveolar and
bronchiolar epithelium.
2. Papillary masses are present in adjacent
alveoli

18. Tumor nodule surrounded by macrophages

19. Diagnosis
1. Clinical signs
2. PM lesions
3. Histopathology of lung tissue
4. Differential diagnosis with:
1. Parasitic pneumonia.
2. Progressive pneumonia
3. Enzootic pneumonia
A simple test can be used to differentiate the adenomatosis
from these diseases. Elevation of the hindquarters of
the affected sheep (wheelbarrow test) resulting in fluid
run out of the nostril in severely affected animals

20. Treatment
• There no treatment but control by culling of the
affected sheep and goat.

21. Prevention:
1. Slaughter of affected and contact animals
2. Cleaning and disinfection of premises before
replacing with sheep from clean flock.

22. Questions