I think calling it zonata disease (ZD) and advocating that they be euthanized prior to the development of neurological symptoms is jumping the gum. I admit to knowing very little about this topic but occasionally we all loose snakes to unknown factors and mother nature cares a lick about how much we pay for them when it happens.
If the animals were established neonates that looked good when they came in and come from a breeder with an established rep I'd assume there is an environmental issue at play and get busy working on it.
IMHO, euthanizing them and expecting a refund is poor advice.
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“Nothing is at last sacred but the integrity of your own mind.” Emmerson
