BOTS.

Sun (Christchurch), Volume 1, Issue 8, 14 February 1914, Page 2 (Supplement)

BOTS.

THEIR POWERS OF RESISTANCE. ■ ; t -A short time ago I received, through Mr Hubbard, Inspector of Stock, Mastcrton, two specimens of bots taken from the nasal cavities of a sheep. These had been brought by a farmer to the local office of the department for identification. They proved on examination to be larv* of the sheep-fly (CE.strus ovis). . . The parasites had been placed by Mr Hubbard at about noon on November 22 in a glass-stoppered r ~ bottle containing 2 per cent formalin solution. On receiving the bottle at the laboratory two days later I was surprised to' find on removal from the solution that one of them was alive. On being held in the hand or exposed to sunlight on the laboratory bench it slowly extended itself, and commenced to move quickly away. The remaining bot was dead. In order to ascertain how long these creatures could support life in such an intolerable medium, I replaced the live bot in the formalin solution, removing it each day to see whether, it showed any signs of life. The warmth of the hand or sunlight seemed to have a revivifying effect, for up till November 22 on the seventh day after complete immersion in the solution, it still remained alive. . The natural powers of resistance of such lowly forms are enormous, and it inay well be contended even in this case that the parasite finally succumbr ed from prolonged exposure in an tinsuitable environment rather than to the poisonous effects of the formalinl This observation serves to illustrate how ineffectual is the administration of drugs designed to destroy these parasites during the life of theii' host, and should cause farmers to pause before employing any of the quaek remedies. which are advertised from time to time as cure's for bots.—H. A. EElt>, P.8.C.V.5., in : the "Journal of Agriculture.'' _<