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Froggatt (W. W. and J. L.). Sugestions in regard to the Checking of 

 Sheep Maggot Flies.— J^nc. Gaz.N.S.W., Sydney, xxv, no. 9, 

 September 1914, pp. 753-755. 



This is an account of one year's experiments, carried out under 

 natural surroundings at the Government Sheep Fly Experiment 

 Station. As the summer advanced, it was found that most of the 

 flies congregated in sheltered areas, chiefly near water, while any dead 

 stock and other carrion, in which the flies breed, were invariably found 

 in the vicinity of the watering-places and sheep camps. It is clear 

 that the flies which infest the live wool of sheep only breed in the first 

 instance in decaying animal matter ; therefore, all such matter must 

 be destroyed, with the result that the numbers of the flies will be 

 greatly reduced and their natural enemies more effectively assist m 

 their control. Where a recently dead animal is found, and the flies 

 are very plentiful, enormous numbers can be attracted and killed by 

 half skinning the carcase and slashing the flesh, and then treating it 

 with a solution of 1 lb. arsenic dissolved by boiling in 5 gallons of water. 

 Within the second day, the action of the arsenic hardens the flesh 

 and stops decomposition, but the carcase can be turned over and 

 the under surface will act as a poison-bait for another day when so 

 treated. The remains will not be blown after such treatment, if the 

 carcase has been thoroughly soaked with the poison, nor will birds or 

 animals be attracted to it, but it is best to burn it if fuel is available. 

 All offal found infested with maggots should be burnt ; the proper 

 method is to turn the carcase over, make a fire where it has been 

 resting, turn it back on to the firewood heap, and see that everything 

 is consumed. The usual method adopted is to pile some brushwood 

 against the back of the animal and set fire to it ; a sheep may be 

 incinerated sufficiently by this means, but not a horse or bullock. 

 Numerous examples of animals thus partially burnt, which were 

 found to shelter millions of maggots, protected beneath the burnt 

 skin from every kind of bird, have been seen. One of the contributing 

 causes to the enormous increase of the blow-fly pest— dead poisoned 

 rabbits— no longer exists over a very large area. 



When once the sheep are attacked, the maggots under the protection 

 of the fleece can only be destroyed by shearing ofl the infested wool, 

 and treating with some mixture to kiU or drive out those exposed. 

 This entails a great deal of labour and expense, besides the injury to 

 the animal and the loss of wool. A long series of experiments con- 

 ducted with a number of the most popular preparations for killing 

 maggots in the wool, in spite of the claims put forward by the vendors, 

 proved that they are not more than palliatives, and that the most 

 efiective damaged the wool. On an average, the wool on a sheep's 

 back grows at the rate of I inch per month, so that there is always 

 unpoisoned wool open to infection on a sheep that has once been blown, 

 and unless all ofiensive wool is removed or deodorised, the sheep is 

 very likely to become reinfested. 



Endeavours have been made to obtain some mixture or essential oil 

 which will entice the flies away from the sheep to traps or poisoned 

 baits, or induce them to oviposit on material treated with such attrac- 

 tive properties, where the maggots, when hatched, will die. Most of 

 the experiments have so far been negative, but the authors think 



