BLOWFLY MAGGOTS

Southland Times, Issue 20955, 12 December 1929, Page 6

BLOWFLY MAGGOTS

ATTACKS ON LIVING SHEEP. BENEFICIAL RESEARCH WORK. (Per United Press Association.) Nelson, December 11. During the past few years, one of the major problems engaging the attention of Dr. D. Miller, of the Cawthron Institute, has been the establishment of a parasite for the control, of blowflies. The need for some such control arose from the attacks of blowfly maggots upon living sheep, causing very heavy mortality in many parts of the country. Statistics collected over a period of several years show that throughout the Dominion, the losses among sheep froni maggot infestation average some £400,000 annually. Dr Miller imported from England in 1926 a parasite alysia, and the first step was to develop a method by which it could be reared successfully for purposes of liberation. This having been accomplished, small scale liberations were made at first, but owing to lack of funds, mass production of the parasite necessary for rapid establishment could not be undertaken. However, this difficulty was overcome by the New Zealand Sheep Owners Federation granting a sum of money which has enabled the alysia to be developed on a large scale at the Cawthron Institute, and extensively liberated during the present season. An examination of maggot infested carcases in a field where the parasites were liberated last summer and autumn show that the alysia was present busily engaged in parasiting the maggots. The actual establishment of this parasite under field conditions is a matter of very great satisfaction and subjection of the blowfly now depends upon the extent the parasite will effectively develop in its new environment. Meantime, liberation continues from the institute’s insectaries.