精选优质文档-倾情为你奉上unit3What is Animal Welfare?IntroductionHuman understanding of animalsespecially their sentience, needs and naturesis developing all the time.The physical states of poor welfare are more readily accessible and understandable(particularly for veterinarians,who undertook much of the early work on welfare).But new research leads naturally to greater understanding of mental states and needs and natures.This is particularly true of ethological research,including preference
