We found seventeen dairy cattle with the abnormal signs in cardiovascular and gastrointestinal systems after feeding of the yew foilage. Among them three cattle were dead due to yew poisoning. Among the remaining fourteen dairy cattle, four cattle showed similar symptoms as did dead cattle. Although the remaining ten dairy cattle did not show any abnormal signs, we conducted a therapy of forced magnesium sulfate infusion because the yew consumption might have been occurred in all cattle. As a result of the therapy, we could not found further signs of yew poisoning. The performance of the therapy and the treatment procedures adapted by the therapy could be concluded as follows: The cardioselective toxicity and inhibition of peristaltic activity by the taxine in yew foilage might be involved in the symptoms of acute poisoning as anorexia, dullness, muscle tremor, dyspnea, and sudden death. We also performed the dose response relationship of taxine to the range of clinical symptoms and examined recovery performances. Through the autopsy of the cattle, we could confirm the presence of yew foilages that might have caused the poisoning in the gastrointestinal tract. However, we could not identify further abnormalities in other organs. In this case report, we demonstrated that practice of the forced magnesium sulfate infusion in yew poisoning was helpful for the attenuating the taxine poisoning by blocking the further proceeding of the toxic effect.