1. Ministry of Higher Education and Scientific Research
University of Al-Qadissiyia
Collage of Veterinary Medicine
Practical Poultry Diseases
Forth Stage
Marek’s Disease (MD)
Assist. Lecturer
Abbas Hadi Jasim Al-Mossawi

2. Marek’s Disease (MD) Etiology Herpes Virus

3. depression, weight loss, and diarrhea

4. Paresis

5. Paresis and paralysis are usually asymmetrical one leg forward and one leg backward

6. Leg paresis (partial paralysis)

7. irregular pupil

8. Lymphoid infiltration of the iris may interfere with normal pupil dilation and constriction.

9. A lymphoma lesion in the wall of the gizzard

10. Tumor in the kidney

11. Unilateral enlargement of sciatic nerve

12. Grey iris and irregular pupil

13. Ocular lesions, due to lymphoid infiltration of iris that causes white discoloration. The pupil is often irregular and does not respond to light

14. Enlarged of feather follicles

15. lymphoproliferative skin lesions

16. Swelling of the feather follicles

17. Tumors on the Liver

18. tumors in the liver

19. tumors in the spleen

20. Enlarged kidneys , firm on palpation, and may have white to grey areas of discoloration

21. Lymphomas in spleen, giving the organ a mottled white appearance

22. nodules on kidney and ovary lead to enlargement

23. tumors in the ovary

24. multiple lymphomatous lesions in the lungs.

25. Tumors in the heart

26. Tumor in the heart

27. A nodular lymphoma in the mucosa of the proventriculus

28. White lesions in the wall of the proventriculus

29. tumors in the intestines.

30. tumors have infiltrated the jejunum and surrounding mesentery

31. A large number of tumors in the pancreas

32. Unilateral enlargement of sciatic nerve

33. Unilateral enlargement of sciatic nerve