A PRELIMINARY STUDY ON BOTULIN MODEL C FOR KILLING PIKA

We determined the virulence of botulin model C with no germ for Plateau pika, characterization of toxin and killing test in vast area. The botulin model C has a strong virulence to pika, the main pest in Qinghai-Tibetan Plateau. Produced by rutine method, it is one hundred thousand MLD white mcuse/ml.The LD50 is 1.71μl/ kg(intubation oral) to pika. The dosage of botulin has a close relation to death time. Heavy dosage makes pika die rapidly while light slowly. After taking it, pika show immuno-reaction quickly, secondry poisoning will not happen. Make the botulin poison bait and it is palatable to pika. In natural environment it lose its virulence rapidly. We had deratization tests in Tie-bujia of Gonghe county, Gade county, Darlag county and Tongde county of Qinghai Province in autumn, winter and spring for two years.The test area added up to more than 13,334ha.By testing in large wild area, using the botulin poison bait to kill pika in whiter, it had a powerful poison effect, coming up to 98%. As a new rodenticide, it has many advantages of being convenient in use, in safety to man or animal, without environmental pollution and so on, and may be put into use to a great extent.