I have heard some pretty bad sounds coming from snakes in shed...even to the point of open mouth breathing. To be on the safe side, I'd have him checked by a vet, but sometimes the head swells and the nostrils get blocked by impending shed skin and you'll swear they have an RI. Once they shed, it all goes away.
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3.2~Cornsnakes
3.4.2~Green tree python
3.3.1~ATB
1.1~Sibon Nebulatus
Dogs, cats, horses....
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