THE LATEST SHEEP SCOURGE.

Wairarapa Age, Volume XXXI, Issue 9041, 17 March 1908, Page 6

THE LATEST SHEEP SCOURGE.

THE SHEEP MAGGOT.

SUSPECTED APPEARANCE AT TE NUI.

A VERY UNDESIRABLE PEST,

Two or three days ago the veterinary division of the Agricultural Department distributed a leaflet among the farming community containing information of very considerable importance to farmers, and treating on a scourge to sheep hitherto almost unknown in New Zealand—the sheepmaggot. The opening remarks of the leaflet issued by the Chief Veterinarian, Mr J. A. Gilruth, ran as follow : The Sheep Maggot.—During the past summer this pest to the flockowner was proved to exist in New Zealand, and though, as yet, definitely recognised in only North Otago, in view of the fact that it is in many parts of the world a veritable scourge, sheepowners are cautioned to be on the outlook for its appearance among their flocks, and to take all precautions to prevent its spread, as well as its ravages. If in older countries with smal' flocks, under constant supervision, 1 the maggot in certain seasons is a constant scource of worry and loss to farmers, how much more serious might it not become in the dominion, where flocks are larger and are not, and could only with difficulty be, subject to the same watchful care. This is well seen in certain parts of New South Wales and Victoria, where of recent years a species of maggot-fly (the nature of which is apparently noc yet definitely determined) has been playing havoc with sheep, and to such an extent that some reports mention 10 per cent, of cases as having occurred amongst cartain flocks of ewes. A Wairarapa Age reporter, in conversation with a Departmental official last week, was informed that now that local sheep were suffering more or less from the effects of extremely poor pastures, it was of the greatest importance that farmers should heed the injunction contained in the Chief Veterinaran's remarks, as it was not at all improbable that as some sheep were in very poor condition the fly might manifest itself. The officials' words have apparently proved prophetic, as yesterday the local branch of the Stock Department received some specimens from a Te Nui settler of a fly which is believed to be identical with that illustrated in the leaflet, and which produces the larvae which develop into the sheep maggot. The size is exactly the same, the tint is the same, and the markings on the head are similar to that shown in the leaflet illustration. Smaller than the ordinary "blue-bottle," it is of a greenish-blue tint, but is otherwise similar in appearance and is frequently confounded with that fly. The leaflet states that in most countries where the sheep-maggot is plentiful the parent is popularly considered to be the common "bluebottle" (Calliphora vomitoria), but this is erroneous. The "blue-bottle" lays its eggs on carrion and like material, on which the larvae feed after hatching, but there is no evidence that they are capable of existing and developing on the live animal. The sheep-~fly lays its eggs in the wool of sheep, particularly those whose wool is dirty, lambs and hoggets suffering from diarrhoea and consequent soiling of the hindquarters being especially prone to attacks. Sheep and lambs which are free from soiled wool are not, however, exempt from attack when the fly is prevalent during the summer months, particularly cowards the latter end of the season. Showery weather, and long grass on dewy mornings, rendering the wool moist, seem to exert an influence in attracting the fly. Naturally, wounds and abrasions of the skin are also likely places of attack. Dead sheep, especially those left unskinned, in any case afford an excellent breeding-ground for the parasites, so that one of the first lines of defence is burial of all dead sheep so soon as found. In a comparatively short time after the eggs are laid the young maggots are hatched out and immediately travel towards the skin, where they endure irritation and inflammation, which is only aggravated by the attempts of the animal to obtain relief. Soon the maggots burrow through the skin and pass between that and the muscles, and if not observed early they will ultimately burrow very deeply, cases having been seen in which they have eaten ' their way right into the abdominal cavity before death of the animal occurred. Symptoms.—The symptoms consist of attempts to remove the cause of the irritatiion by biting the part affected, frequent rubbing, rapid agitation of the tail, etc. If the skin has become partially destroyed before the affected sheep is seen, listlessness may be the only really discerned evidence, but a cireful observer may—especially if the animal is attacked in the side, as lambs frequently are—-detect a damp, dirtylooking patch of wool due to discoloration by exudation from the skin. So rapid is the whole course of events that, even in a carefully watched flock, cases of extensive damage are not rare and sometimes even death is impossible to prevent. The leaflet should be carefully read by all farmers in this district, seeing that it is almost certain that the Te Nui specimens are the identical scourge. They are, however, to be forwarded to Wellington for investigation, and the result will be awaited with much interest, not to say anxiety, as to have a deadly pest of the character described at the present time means a loss of thousands of pounds to the district if curative or preventive measures are not taken. Full instructions for the treatment cf affected sheep are given, also preventive measures. Any farmers suspecting their pheep to be attacked with the maggot are earnestly requested to secure a specimen fly, and forward it to the Stock Department for identification.