Putting a known wild caught rattlesnake, or any herp for that matter, that hasn't been quarantined for at least 60-90 days (far removed from any established collection) is a recipe for disaster. The snake could have simply died from stress, however, there are a number of known viruses that can wipe out entire collections due to their airborne tendencies (not trying to make you worry, that's just reality). Keep a close eye on the rest of your collection and it may not be a bad idea to thoroughly disinfect any nearby cages and keep the animals in simple set ups (newspaper, hide box, water bowl) until you know you are free and clear.
As far as the cause of death, you would have to do a necropsy for a firm analysis. EDB's are certainly prone to stress, however, it could be stress from a less than optimal environment you created. I have found, particularly with this species, that they are very prone to heat stress issues (they do NOT do well when ambient temps go above 78-80 deg. f even though I do allow my EDB's to bask in areas that reach 88-90 deg F they can also cool down by going to areas in the same enclosure that go down to the lower 70's).
Rob Carmichael, Curator
The Wildlife Discovery Center at Elawa Farm
Lake Forest, IL
>>O-kay people I got an edb from a guy in alabama.It was wild caught and a juvenile.I had it 2 weeks and it shed,but would not feed on anything I tried.Well I go down in my herp room this mourning and dead!Could it have been from nerves or stress?.Everything else seems fine.Help!
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Rob Carmichael, Curator
The Wildlife Discovery Center at Elawa Farm
Lake Forest, IL