Chicken Anemia Virus and Immunosuppression: Impact on Marek´s Disease Vaccine Protection
Published:August 15, 2014
Summary
INTRODUCTION
Although MD is in general well controlled by vaccination in ovo or at one d of age, MD remains a concern for several reasons. First of all, vaccination practices are often suboptimal resulting in some vaccine breaks. Proper use of standard operating procedures at the hatchery remains essential for optimal protection and has been the topic of many presentations. The short-term fi...
I have a broiler breeder flock (production floor space 1.6 s.ft/bird) suffer with Marek's disease at the age of 28 week , in rearing (floor space 1.2 s.ft/b) when i did CAV vaccine right after 12 day clinical sign of CAV appear after 3week gradually it was diffuse and cause 2.5% mortality, beside these above fact ,my question is that less floor space can contribute in said problem or CAV the only factor that create immunosuppression and cause Marek's with the result low production ,less hatchable egg and less hatchability .
Thanks
Both, CAV and limited floor space, can contribute to MD mortality. The latter by causing stress and the former by interfering with immune responses. I am not clear what you meant with"i did CAV vaccine right after 12 day clinical sign of CAV appear after 3week gradually it was diffuse and cause 2.5% mortality",
Did you vaccinate at 12 days of age against CAV? And di you then get CAV lesions? if so that may have also interfered with the development of vaccine-induced MD immunity. What kind of CAV vaccine did you use? Were your young chicks positive for maternal antibodies against CAV?If so, vaccination at 12 days of age with alive CAV vaccine may not even have induced a CAV immune response because maternal antibodies would have neutralized live CAV vaccine virus
It is good that my Prof. Schat presented this finding; it is a serious challenge as most poultry farms are not screened for CA infection in most parts of the world. Thank you Prof. Schat. Jwander
