Avian Pox Virus is common in birds that nest close together. This is a boat-tail grackle chick that shows the typical whitish canker sores around the edge of its beak. Eyes are also commonly affected. Those external lesions are not that serious. But they often continue deep into the mouth and throat where they obstruct the bird's respiration. The virus is very tough and persistent in the environment. Never bring a bird that looks like this into an area where other birds are present. The only thing I have found that will decontaminate an aviary is a 10% bleach solution. But dirt and grime must be removed first. Click on this image to enlarge it

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