Question: query regarding use of anthalminticin cattle  during the time of gestation period 
Answer: deworming should be dne before the implentation , or after calving [ generally within 3 month, 90 days after calving  ]but in some cases where parasitic load is maximum--in such cases anthalmintic can be used with the suggestion of a veterinarian ,otherwise parasite or parasitic  ova may affect the developing fetus -- if deworming is not done in time