first may I say that older birds can and do get mareks
as high stress from heat and severe cold causes mareks also.
the best time is to vaccinate at day one of their life
but older birds can be vaccinated
You also need to get on the high content of Vit's that is suggested.
you might read this exserp from Peter Brown's discussion of mareks
http://www.firststatevetsupply.com/poultry-health/mareks-disease.html
and apply the thought here
Peter Brown said
Can older birds be vaccinated for Mareks Disease ? The answer to this question is ,yes. The age of the bird really does not matter as long as the bird has not been exposed to the Mareks Virus prior to vaccination.
If a bird that has not been vaccinated for Mareks Disease comes down with the obvious symptoms of Mareks it may be of value to vaccinate anyway.
There is some research to show that some birds may recover after vaccination.
This would possibly work on birds whether or not they were vaccinated before. Some research has suggested that re-vaccination 4 to 6 weeks after the initial vaccination was of value in preventing new cases of Mareks disease in high risk areas.
It is important to keep in mind that birds that have been infected are shedding this virus at a very heavy rate from their follicles and it would be of value to keep feathers about your coop cleaned up.
Regular spraying with oxine will go a long way in keeping this disease as well as other diseases under control. Concerning the use of bleach as a disinfectant: go ahead and use it if you so desire but be aware that to my knowledge there are no studies to show the effectiveness of bleach against any disease organism.
Oxine has reams of test data against a wide range of Pathogens and is designed to be used specifically for disinfection purposes. Consider this: during the anthrax scare of a few years ago, The Hart Senate Office Building in Washington,D.C. was heavily contaminated with Anthrax.
The disinfectant of choice (although it was used in its Gaseous Form) was Oxine. I dont recall them using bleach as an alternative. Remember that you get what you pay for . My Dad once told me that if you want good clean quality Oats that they come at a price,and that if you want the Oats after they come through the horse they come a bit cheaper. Nuf said.
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