1) Sheep and Goat Medicine. DG Pugh.  WB Saunders Company 2002. Diseases of the Resp System pg 118-120

2) Veterinary Medicine: A Textbook of the Disease of Cattle, Sheep, Pigs, Goats and Horses. Otto Radostits, Clive Gay, Douglas Blood, Kenneth Hinchcliff. 9th Ed.  Harcourt Publishers 2000. Chapter 22 Disease Caused by Viruses and Chlamydia II pg 1186-1189

3) Arsenault J.; Girard C.; Dubreuil P.; et al.Prevalence of and carcass condemnation from maedi-visna, paratuberculosis and caseous lymphadenitis in culled sheep from Quebec, Canada. Preventive Veterinary Medicine 59 (1/2): 67-81 2003

4) Simard C.; Morley R. S.Seroprevalence of maedi-visna in Canadian sheep.
Canadian Journal of Veterinary Research 55 (3): 269-273 1991

5) Fournier D.; Campbell J. R.; Middleton D. M.Prevalence of maedi-visna infection in culled ewes in Alberta. Canadian Veterinary Journal 47 (5): 460-466 2006

6) Campbell J. R.; Menzies P. I.; Waltner-Toews D.; et al.The seroprevalence of maedi-visna in Ontario sheep flocks and its relationship to flock demographics and management practices. Canadian Veterinary Journal 35 (1): 39-44 1994

7) Necropsy Show and Tell: Veterinary Pathology Images.

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