questions: query regarding use of anthalmintic 
 answers: anthalmintic should be given at four month of age in case of calf but it mmay recommanded in earlier depending the severirity of infestation / since the rumen develope start& complete at four month of age .most of the anthalmintic are given in oral route , may cause digestive & productive performance in future specially in female calf . besides this anthalmintic are corosive in nature may effect the developing cell of stomach