LAMINITIS

Otago Witness, Issue 2572, 1 July 1903, Page 56

LAMINITIS

This malady conskts of inflammation of various degrees of intensity affecting the whole or greater part of tho vascular membrane whioh covers the internal foot. The causes of the inflammatory condition are excessive exertion on hard roads in hot dry weather, heavy draught work, find, among lighter breeds-, travelling at a rapid pace, as in the case of a quick journey along a hard road when the animal is overweighted either in riding or driving. Independently, however, of these causes, the character of which is perfectly obvious, and the results of which might well bo expected, 'there is a more mysterious cause, which is described as motastatio. v When an animal has his feet battered along a hard road, and particularly when added to these condifcicas he is overweighted, ft is intelligible that the internal foot, including the vascular and nervous structures, should suffer ; but it would not be expected that a horse standing in a box for some time owing to an acute inflammatory attack of the lungs or intestines should suffer from an equally acute attack of inflammatkin of the internal foot, either of the hind or the fore, and sometimes of all four feet. Thie, however, 13 an event which not uncommonly occurs, and is attributed to metastasis — • that is, bhe extension, more properly called! the transmission, of the inflammation from, the internal orgatn to the- foot. It will clear the ground considerably if the fact is afc once stated that the degree of inflammation determines three different stages of the disease, whioh are marked by different kinda of changes in the structures of the foot.

There, ie first the acute etage, next the sub-acute, and Hie third stage, which ia chronic. These three stages are sometimes consecutive, following in a regular linfe from the first to the last — the acute jtage subsides imto tho sub-acute, and that into the chronio; but, on the other hand, each stage n?ay remain quite independent of the ofcher. An acute attack of fever in the feet may terminate in recovery or in the death of the animal. The sub-acute form may be 6een at the commencement, and may continue to impair tho animal's actkm, and then re-covery-may take place. The chronio is the most insidious form of the three, and may remain for a long time without attracting much attention. The animal's action is impaired, but not sufficiently so to interfere with its woilc, while tho character of the disease ie indicated by regular changes in the exterior of tJ'.e foot. The horn is secreted iv successive layers, giving to the hoof a ringed appearance, the sole gradually loses its concave form and becomes flattened, and the entire horn structure grows exceedingly brittle, so that the breaking away of the nails which hold the ehoea is a very common, occurrence, and in vexy advanced forms of the disease the sole becomes convex, and the texture of the hoof aesumes the character of a large piece of pumice stone, and, in fact, tJi© horse ia said to 'be suffering from pumiced foot-.

The first form of the disease — the acute— is the most serious, and is occasionally attended by the death of the animal a few days after the attack begins. Ib may very well be imagined that the ocourrenc© of acute inflammation in a vascular membrane which is enclospd: in. a dense, hard, and absolutely unyielding box must necessarily bo productive of intense suffering, and the {act of animals dying from mere intensity of pain is perfeotly well known to pafchalogisits. Should, however, the system be 6trong enough to resist the first invasion of the disease, the animal lies groaning and strugling, perhaps, for 24 or even 48 hours; exudation of fibrinous material rnSxed with blood goes on rapiclly, and the material begins to escape round the coronet; the sole, also, ie pushed out of its plaoe at the toe, and the point of the coffin bone has, in extreme cases, been pushed through the horny covering. As a rule, before thie stage is reached the case will be seen to be perfectly hopeless, and the animal will be destroyed; but instances have occurred where vain efforts have been continued, in the hope of curing the case, until the hoofs of the fare feet, wliich are the parts usually attackied, have become ?o much loosened that their separation could not be looked upoai as otherwise' than imminent. During the whole time, from the beginning of the attack to the finish, the animal remains on the ground 1 . No amount of persuasion will induce it to rise, nor, indeed, would if he possible for it to stand if it were lifted cm to its feet, a device which has occasionally been resorted to by the aid of slings and pulleys, but without any beneficial effect. _ These very severe cases, in which the animal is found lying on the floor of its stall or box, are usually metastatie. Another form of the acute attack exhibits itself probably on the morning after severe exrrtion on the hard road or in the huntamg field, when the ground is hard, by the peculiar attitude of the animal, which ia S&en to bo standing- with the hind le#a considerably advanced under tho body; the fore legs are also put forward, and the animal 1 as much ac possible rests upon its heels ; the head is protruded, the neck is quite stiff, and bhe muscles sharply defned, and more than once in the writer's experience a horse in this condition has been condemned aa suffering from tetanuf— not. of course, by a professional man. who, whatever his first impressions misrht be from the animal's appearance, would adopt one or two simple test«, whioh would decide fch© question without difficulty By going up to the animal rather suddenly and moving his hand towards the eye he would, in the case of tetanus, ob-orve the eye pulled into the orbit by the retractor muscle and the haw protruded. Deciding that the oase is nofl one of t/cfxnue, the alternative disease, acutai /laminitis. at ones occurs to him, and h« applies his hand to the fore hoofs, the ternpfrature of whioh lie finds to be raided considerably. Next, on attempting to lift one of the fore feet, he finds that the animal resists tho movement, and if he does succeed! in raising a portion of the hoof a very short pnace from the ground, it is pulled out of his grasp by the violent movement which the animal makes to prevent itself from falling, and he then commenca treatment according to two or three different methods whioh he may deem to be expedient.—The Field.