maybe mites?

[gonesnakee]

Oil damages their scales & can make them fall in in large groups.
Lots of things would kill them if it was smeared on the snake.
Peanut butter, margarine, mayo, vasoline, hand cream you name it would smother mites on the animal itself.
As far as that goes plain old water would do the trick there with no ill effect as all you ar doing is "drowning" the mites, however none of this would kill mites not on the animal itself nor any of the eggs which would be present in or around the enclosures.
NIX & P.A.M. would not only kill all mites on the animals itself, but any in or around the enclosures as well as any eggs.
Smearing the snake up with ________ doesn't solve the problem & depending what is smeared on it cause more issues than it had to begin with & just prolong the mite infestation as well as it does nothing to the other mites or their eggs. Mark