444 Journal of Agriculture. [8 July, 1908. 



DISEASES OF THE SKIN. 



{Continued from page 343.) 

 S. S. Cameron, M.R.C.V.S., Chief Veterinary Officer. 



Parasitic Skix Diskasus. — i. AxiMiL parasites. — Fly-l)low on Sheep — Cattle Warbles— Fleas [piilecpf!) — 

 L\ce {Hceiii'it(ipliti(.'!)—b''j\vl Lice on Animals— Ticks, Ikjiwi- tick (Ixodex A mericanus a.n:\ /li/i/inhns -ri 

 equina), cattle tick (/xorfey hovU), doj,' tick {Ixo-lrx in-inn^), sheep tick (iK'tto^^/int/ws m-iiin^}. fowl 

 tick (Argax A iii^nca)iu>i)—yi!mge or Scabies (mrmjilfs, paoroptes, and xi/mbiote.-i} — Arne (ih'innlrc 

 follieulonimK ri. — vesetable parasites. — Dermatoniycosis, Rin;;-worni (trichnpliiiton tun^in-oiis — 

 Queensland Man;;e or Parasitic Eczema {trichophi/tfiii ep'dan^). 



II. -PARASITIC SKIN DISEASES. 



I. — Animal Parasites. 



Fly-blow on Sl^eep. 



It is only during recent years that fly-blow has become a pest amongst 

 Australian sheep. Until the nineties fly-blown sheep were practically 

 unknown but since the break up of the drought in 1902 they have become 

 in .some districts so common as to constitute a serious menace to profitable 

 sheep husbandry. This sudden incidence of the trouble has been put 

 down to the unusually cool summers experienced for it is believed that a 

 shade temperature of 112 degrees will prevent the development of the 

 larvae of the fly concerned, and this temperature has not been reached in 

 many parts of Australia during the period referred to. A more likely 

 hypothesis is that one of the more pernicious varieties of flies in this 

 respect has only lately been introduced, probably through the medium of 

 imported sheep, a large number of which have arrived in Australia since 

 ine boom in the mutton breeds of sheep commenced. 



The flies mostly concerned in the production of this trouble belong to 

 Ihe genus Lucilia which are characterized by their bright metallic colours, 

 short and round abdomen, wide set wangs and a soft proboscis. The most 

 [^ernicious of the genus are : — 



(a) Lucilia macallaria — " It measures 9 mm. to 10 mm. (one-third 

 of an inch) and is recognised by its blue thorax streaked with 

 three darker blue bands of a purple tint ; the pads are black 

 and the wings brown at the base." (Neumann.) 

 {b) Lucilia sericata is somewhat similar but golden-green in colour. 



The trouble is most prevalent during mild winter and spring weather 

 from July onwards. At these seasons the immature grass produces a 

 laxative effect, and the tail and rump wool is so "dirtied" as to attract the 

 fly, and be a suitable spot for the deposition of the blow. It is also well 

 known that the fly itself is most active in sultry weather and after rain, 

 and at such times a sharp look-out should be kept for the uneasy restless- 

 ness, stamping, biting, tail shaking, and running about, which are the first 

 indications of the torment of burrov/ing maggots. Sheep with dirty tails 

 and rumps from diarrhoea should be specially watched. If the fly is very 

 bad, and it is possible to change the pasture, this should be done, or all 

 sheep showing signs of diarrhoea should be drafted and changed. 



Treatment. — The curative treatment of "the fly " so far as destruc- 

 tion of the maggots is concerned is simplicity itself, for the pests are 

 extremely sensitive to the action of numerous agents, such as spirit of tar. 

 kero.sene emulsion, solution of creolin, or any of the phenyle dips. 



