Ivermectin is not a pyrethrin according to my vet. It can be placed on the shoulder blades of the mice by the drop, further reducing air emissions. It is one of the most popular ingredients in Heartworm medications, Heartguard and Iverhart are the ones we sell. Ivermectin can be used on and in your snake for worming him and treating ticks and mites. It has to be safer than anything else for your snakes since it can be used to treat them as well. Collies and breeds related to Collie types are the only contraindications for using ivermectin in dogs. Just my opinion your mileage may vary Ivermectin can also treat some internal parasites that rodents can have, another bonus.
*Fila*
Pets,cattle and so on yes you can put it on directly, But rodents your going ot be feeding you dont want it directly on them. The bedding is fine as the wood will absorb it enough to keep it off them 100% but enough to kill the mites.