SHEEP-DIPPING METHODS

Hawke's Bay Herald-Tribune, Issue 31, 20 February 1937, Page 19

SHEEP-DIPPING METHODS

- J . ■ : • 1 1 " , . f ' , * i Will Spraying Prove More . EBective? TRIALS IN BRITAIN Ib sheep-dipping but of date? Does tdtal immersion' in' a' bath of dip diluted with water rcally perfqrm the ffihPtion for which it was designed? These are two questions which, in all probability, have often been asked by sheepfarmers in HaWke 's Bay. To ' tho?e who have doubts ds to the qffltaey of the present* system', the newer method of spraying ■ may have an appeal. It, has certainly- attracted attPhtion in Britain where the spraying system has been developedi * ' Dr. Allaii Fraser, who attehded a demonstration of Sheep fepraying ar-.. ranged by the North of Scotland College of Agriculture', * makes some per- • tiheht comment on thiS gupstion. * "What are 'the disadvantages of dipping that a new method should be, sought?", iie;askes. ^'Obviously, if the customary 'method wferp a hundrtfd per cent satisfactory, a; seareh for. improvement woiild be* a waste of tiinp. Ordinary dippihg is, however, for from being entirely satisfactpry, even when properly performed^ and T have recpgllised that fact for some time. As sohietimes done,' it is a perfunctory compliance with the law's requirements, and, from the point of view of benefit to the sheep, a pure waste of efiort. Ptesent Wpaknessp* , "The fpllowing are in my view, weaknesses in dipping sheep with ordinary dips and in the ordinary way; In the first place the dip does not always penetrato to the skin—the place Where its aotion is wanted. I have often examined sheep in the dipping pens and found Ihe skin perfectly "dry. In the second place the strength of the dip is nofc constant. 6ne fills the bath and pours in sUfficient. to make a correct dilution. So far, so good. But by the time the first few sheep have been dealt with, is the strength of the dip the same? To judge by the coloilr of the sheep it ia not. The first sheep always come out darker than those that follow. I understand that , chemical analysis shows mttch the same sort of thing. "Thirdly, by the time the dipper is ready for re-lilling it is more than a little dirty. The aung floats as a scum on the surface, and it is difficult to skim off. If the sheep liappen to be scouring, the water may be quite foul. Since soiled wool is an attraetion to blowfly, a dirty dipper may * beeorne' an actual chuse of strike^ "In the method of spraying I saw .demonstrated these three diBadvantages. were entirely avoided. The dip pettetrated to the skin; the dip wae always of the same strength; there was no fouling of the fiip by - dung. The methqd itself wus quite simple. A small engine worked a pump which forced the dip through fine nozzles. The spray produced was like driving mist. The nozzles openefi intt> a metal . cage eontaining the sheep. . "Tudging from wfiat I saw the method was effective. Aften standing quietly. in the cage for half a piinute. the sheep, when released, was soaked all over- and to the skin. * •. Ingenlpus Accessorica "There were severa.1 gadgets which I thought ingenious. For instance, a bar operated by a lever pressed the sheep into position from behind and held it there. A removable tray collected the droppings, Everything Was workmanlike and convenient. "There thus appear to be several very real advantages in spraying sheep rather than in dipping them. Of course, the apparatus costs money, bnt eo does the installation of a dip. I very much Qoubx whether the spraying machines would cost as much. There is no more labour required and there is an economy in dip. It is also claimed that spraying is a better preventive of blow-fly than dipping, but I think more evidence is needed to prove this, " Unfprtunately, at the present time, spraying does not satisfy legal yequirements, and I cahnot sea any sheepfarm running to a dip and a spraying machine. Ceftainly, spraying would need to have very substantial advantages over dipping as a protection againat hlow-fly before such a double expenditure was justified. On the other hand, I do not see why spraying should not be equal or superior to dipping. If half a minute in a spraying machine of approved design were accepted as a legal * sqbstitute for complete immersion, then I fee] there would be a future for spraying. Otherwise, since the dipping is forced on us by law, the spraying machine must wait."