It is suspected that cats may be more likely to develop permethrin toxicity because they have different liver metabolic pathways to other species â in particular, they have a deficiency in the enzyme hepatic glucuronosyl transferase. Source(s): http://www.fabcats.org/owners/poisons/pe...
Re: Swallowed chunk of rawhide. In all honesty you need to contact your vet. Rawhides do cause blockages, especially in smaller dogs, because the pieces are too large to pass through the intestine. Contact your vet, and ask for some x rays. Cheapest, and most effiecient way to see if there is a blockage, how large the piece is, and if it is moving through.
Rawhide dog chews are dried hypodermic interstitial tissue (second layer of the skin) from cattle raised for meat production. This hypodermic interstitial tissue is quite tough yet flexible, due to collagen fibers that link. During processing the animal's skin is split into inner and outer layers.