Bot in Horses.

Southland Times, Issue 19264, 30 January 1904, Page 4 (Supplement)

Bot in Horses.

(To the Editor). Sir,— Will you permit me, in reply to the expert comments in connection with a letter of mine on the subject of bots in horses, which appeared in the columns of your Times' issue Of 12 til Dec., 1903, to state : .Previous to the introduction of tho bot fly in New Zealand premature deaths among horses wero few and far between, excepting us the result of accident, but since the advent of these pests, the mortality in horses has increased by at least twenty per cent., in many indtances bots, by their presence being the primary cause, if not the direct, by preparing the system as a suitable receptacle for various disorders which givo rise to complications of a severe kind, as for instance when a horse is infected with parasite- and catches cold the eHect becomes the samo in comparison as placing fuel on a smouldering firo. . As to matter instanced as irrelevant in connection with the diQerence in opinions of vets., to my mind it is relevant in so far as the subject of tbis correspondence j originated from a publication stating that most veterinarians had held that bots did not kill horses. Now, however, a vet. in the Southland district, owing to a post mortem he had mode on an animal, was of opinion that- the horse bad been killed by numerous bots setting up intense inflammation of the stomach. This gentleman is strongly supported in the opinion he has given expression to by Messrs Clayler and McTaggort, M.R.C.V.S.L. In their publication they say convulsions, epilepsy and lethargy are frequently caused by bots vellicating and wounding the coats of the stomach and affecting the nerves, and very often by ulcerating the parts, destroy the horse. Clay tor adds, " I have knowr. horses to he much infected with bots, which is tho chief cause why so many hundreds of horses die." In further support of tha destructive capacity of bots, in reply to c;uestions asked by me in the Canterbury Times' issue of 15th February, 1899, Mr J. it. Charlton, M.R.C.V.S.L.. says in those columns :" We have frequently pointed out that tho larvao. by pressure, cause tlie stomach to becomo so attenuated that rupture and death follow." And yet, Mr Editor, there are vets, who lead owners to bolieve that it ia unnecessary j to adopt measures to prevent bots killing their horses. Whilst the difference in opinions op the subject continues valuable animals are annually being lost. In regard to so-called influenza, distemper and fever, it is a well-established fact that horses, when suffering from a severe attack of parasites, such as bots and worms, are subject to colds, coughs and discharge from the nostrils. It is almost unnecessary to add that where there are colds, there is fever. What I said and meant in respect to strangles was not that bots caused this disorder, but that they were responsible for suppression of same, in other words, they interfered with the natural and proper terminatien of an attack of strangles, which generally used to bo by the discharge of pus between the branches of the jaws, after which a quick and permanent recovery took place. When not tenninatina by way of discharge, the accumulations of the disorder are thrown back, upon the systean and tho horso suffers from suppressed strangles. Surely these cannot be classed as haphazard statements, but rather taken as sound physiological theories. As to the account in, the leaflet of post mortem on horse said to have died from so-called Winton disease, or cirrhosis of liver, the report says* : — " At the pyloric ond and for the first six inches of the duodenum thore were a large number of larvae of the oestrus hemorrhoidalis (bots), the mucous membrane being nodular, etc." The report goes on to say :—> " It shows the intimate connection thero is between the stomach and tho disease." I say, sir, this horse's death was caused by bots, at all events, they wero the only primary cause discovered to be present. As to the photograph (No. 1) forwarded, showing hundreds of bots adhering to the stomach, and large numbers of ulcerations in the duodenum, from which tho bots had been removed, no expert comments on the subject of these ulcerations aro made, though they are the most important part of the photograph when wo consider how closo the proximity of the bots thefleiln _o the liver must havo been, as the duodenum is attached to, and resting against that organ. If it did not cause cirrhosis of tho liver or Winton disease, well, to say the least, it would bo a matter of surprise. As to post-mortem symptoms in cows being similar to those Of horses, tbat are said to die of socallod Winton disease, cows are frequently infested with different kinds of parasites. I have at the present time, preserved samples of portions of the abomasum (fourth stomach) of cows, with numbers of parasites adhering, bein^ somewhat similar in, shape to the horse bot, scientifically called amphistoma conicum, There is also the cattle ,bpt fly (oestrus bo vis), then there is fluke or liver worm and hydatids. However, without theso pests there aro many causes which give rise to wasting disease in cattle, such as bad surface water which they drink, cold, damp pastures, etc., which often induce diarrhoea followed by a sort of consumption, -which ia invariably accompanied with disorder of tho liver, possibly cirrhosis. Your contributor of " Rural Notes " says, oven, whon a tuberculous cow's udder is affected people in good health may partake of tho milk of such udders with impunity, but delicate people should not toko tho risk of infection in this way. On similar lines, sir, would. not a horse infected with bots be more subject to attacks of prevalent disorders which would in. such case liave a severer effect than with an animal freo from bots ? In conclusion, thero ls one other little matter upon which I should like to hear an expert's explanation, In reference to an article published in the Evening Post, as follows :— " Mr Chapman, of the Bedford Road (Taranaki), had a unique experience lately. Lost year he was prosecuted for not eradicating ragwort, which had almost taken charge, of his place. When Mr Arden visited the farm, three weeks ago, he found quite fifteen acres entirely covered with ragwort, SO thick* there was hardly a blade of grass. Mr Arden advised him to try tho experiment of eating . the weed down with sheep. This he did, with tho result that, oxcept'in inaccessible places, the ragwort ha*s entirely disappeared, and it is estimated the sheep increased in value qwite half a crown per head." If ragwort is injurious to horses and cattle, why do sheep thrive on* it ?— I am, etc., A. J. KNOCKS.