Letter: Flea collars.
D000818:Animals; D002371:Cat Diseases / Q000517:prevention & control*; D002415:Cats; D004283:Dog Diseases / Q000517:prevention & control*; D004285:Dogs; D004478:Ectoparasitic Infestations / Q000517:prevention & control / Q000662:veterinary*; D005423:Siphonaptera