BLOW-FLY PEST.

Auckland Star, Volume LXVI, Issue 227, 25 September 1935, Page 13

BLOW-FLY PEST.

CONTROL HOPED FOR.

GOOD NEWS FOR FARMERS.

PROTECTION FOR SHEEP,

(From Our Own Correspondent.)

SYDNEY, September 16. It has been officially announced that the Council of Scientific and Industrial Research has discovered a specific which is expected to ensure the control of the blow-fly pest' and render sheep permanently immune from its attack. What this means to our sheepmen may be imagined from the council's estimate that the loss to our flocks from blow-fly attack can be conservatively estimated at £4,000,000 a year. It would be well worth our while to save all that money, to say nothing of the anxiety and labour that this terrible pest occasions every year, throughout our rural districts. The entomological division of the C.5.1.E., under the direction of Dr. Tilyard, whose ability in this direction i 6 well known and recognised in New Zealand, has been experimenting at Canberra with blow-flies for a long time past. The flies are kept in specially warmed cages, supplied with light approximating to the sun's brilliancy, and they are fed on "a carefully balanced diet of dates, sugar and meat," treatment which many people on the dole .would doubtless envy them. Their habits and their rate of propagation have been carefully investigated, and our entomologists are beginning to come to definite conclusions about them. Not the least interesting feature of the study is the amazing /ate at which the species reproduces itself. Dr. Tilyard estimates that the progeny of one pair of blow-flies if provided with sufficient food would in one year equal the weight of the earth!— which is put down at 132 billion billion pounds. Of course figures raised to this scale of magnitude mean little to most people, but they may at least suggest the immensity of this pest and the magnitude of the task undertaken by those who are grappling with it. However, so it is reported, a mixture of boracic acid, with other ingredients, in glycerine in certain proportions, has been proved to cure the blow-fly "strike" on sheep, and it has been proved also to prevent "re-strike" for as long as 40 daye.

Cost of Manufacture. The experts believe that further experiments will enable tliem to render the cure and the immunity permanent; and. it is also claimed for this wonderful new dressing that it is absolutely harmless to the sheep, that it is easy to apply, that it helps to heal the injured area, and that it does not discolour or ! adversely affect the wool. It sounds almost too good to be true, and at present the only "fly in the ointment" seems to be the cost. Manufactured with pure chemicals, the mixture would cost 11/ or 12/ a gallon. But by simplified methods of preparation and by diluting the liquid the cost can be I brought down to about 4/ per gallon; I and this would mean that flocks could be treated in the open fields at a cost of 3d per head; or, with further dilution, for Id per head for the season. If this is only approximately correct, the news should be sure of a most enthusiastic reception from all our sheep farmers. It may be premature to draw any further inference from results which so far have been chiefly in the nature of laboratory experiments, but the fact that the treatment apparently renders the sheep immune from further attacks over a considerable period is most significant and justifies high hopes for its ultimate success. The C.S.I.R. is one of Australia's most important national institutions, and our people are already grateful for the many benefits that its investigations have secured for them. The elimination of the blowfly pest would mean so much to our sheep industry, and therefore to the whole Commonwealth, that further developments will be awaited here with eager anticipation.