Studies on Evaluation Techniques of Anthelmintic Efficacy by Fecal Egg Counts in Cattle Naturally Infected with Helminths

연충감염우에 있어서 충란검사(蟲卵檢査)에 의한 구충효능(驅蟲效能) 평가방법(評價方法)에 관한 연구(硏究)

In the evaluation of anthelmintic efficacy by fecal egg counts for cattle naturally infected with helminths, the reasonable technique of fecal egg counts and the reliable guidelines were determined as follows; 1. Modified technique of Harashigeru and Kim's sedimental tube was the most reasonable in fluke egg counts. 2. Universal egg counting technique was preciser than McMaster egg counting technique and was lower in coefficient variation. 3. Fecal egg counts of pretreatment should be carried out twice and mean of the epg should be calculated. 4. Fecal egg counts of posttreatment should be carried out 3 times and established at suitable intervals in consideration of anthelmintic mechanism and withdrawal days of anthelmintics. 5. If nematodal eggs are not found by UECT in posttreatment, direct flotation method should be carried out. And if positive, this epg was calculated at 20 (factor of UECT; $40{\times}1/2$).