JOINT DISEASE OF LAMBS AND OTHER YOUNG ANIMALS.

Otago Witness, Issue 2433, 31 October 1900, Page 4

JOINT DISEASE OF LAMBS AND OTHER YOUNG ANIMALS.

In quite recent years, the recurrence of serious losses of yo'ang lambs in particular, and occasionally also of young calves and foals, from a malady unknown to tlie^ breeders has been reported from numerous

districts in the colony widely apart. The fatalities have been all the more inexplicable because, of their lecurrence, not ably, _ in well-fed, well-csred-ioi flocks. It not uncommonly happens, however, that many animals r-re simultaneously or concurrently affected, and when this occurs it naturally essum.es an alarming character, and excites,considerfible attention . in the neighbourhood. The descriptions by breeders here of the symptoms manifested during the progress of the disease, though meagre and indefinite, seem to point to the identity of the malady with that long known to Bnush breeders of horses, cattle, oncl sheep as' "joint ill,'' "na-sel ill," "foal ill," and numerous other purely provincial names. Such being the hypothesis, it manifestly concerns stock owners that they should have a clear knowledge of the nature of the disease and the means for preventing it, for, after the ensuing of the changes by which it is recognised, the. hope of recovery is not great. In Great Britain it is generally regarded as a disease of the belter clasji'of highly-fed animal, and statistics of Continental State?, where numerous breeding establishment -> .ire under Government control, furnish further evidence of the correctness of this view. The extent of the losses is variable. Amongst lambs occasionally as many- as 40 or 60 per cent, become affected, and more than half of -these succumb. In some British sbuds a, death rate of nearly 30 per cent, has been met with. During the yeai- 1894 out of 17 foals born in one village in Yorkshire, only two remained alive .\all of the others having died of '"navel ill." , Of knowledge of any disease of this character the most important is that which concerns its cause. With regard to the cpuse of joint ill, until comparatively recently there has been a, great variety of opinion. That mest generally held attributed it to in-and-in breeding and the " scrofulous " condition or constitution of ens or both parents ; indeed, it was generally balieved to 1 be the manifestation of hereditary tuberculosis or scrofula in the offspring— a constitutional disease of the parent transmitted to the progeny before birth. Prominent among the other reputed causes have been improper feeding, irregular working of the mother during pregnancy or the suckling period, overheating of ihe dam, fasting of the foal while ilia mother is at work, cold and damp affecting the parent or young animal, prevalence of cast winds, and exclusive feeding of flocks and herds on turnips or mangels. At other times, probably from the symptoms of lameness and swollen joints." the disease has been regarded us of a rheumatic no lure. The adv-mco ot pathological knowledge lias, however, put the causation of joint ill on a more satisfactory basis. Afc pest mortem examination the microscope has clearly demonstrated that it is nor, tuberculosis or scrofula. Experiments and' closer observation of the living and thi. dead hwe yielded evidence of the communicfibility of the diseisc from the affected to the healthy animnl, po that it has come to be regarded ss a inly contagious affection, mid if communicated from the parent to the offspring it depends upon some other cau<^e than that of scrofula. The better knowledge of the nature of the malady and tlie means for preventing it is instructively discussed in an essay by Prok'hiov John Penberlhy, Royal Vcterniriary College, London. With the view to impart lo stack owners authoritative informs*

tion on the subject, and which will enable them to safeguard their farm animals from attacks, the following extract of the essay is submitted. j "The affection," the professor writes, " is most commonly observed m foals, lambs, and calves, and less frequently in young ; pigs and puppies. It invariably makes its : appearance in the young animal soon after j birth, and its affects are often fatal or such as to render its subject worthless. Though there is sometimes evidence of disease affect- j ing the mother at the same time as the offspring, further experimental proof would seem necessary before we can speak positively as to any connection between the one and the other. It is beyond question that the disease is due to the entrance of a germ, and that this entrance may be, and frequently is, effected after birth. Certain circumstances seem to indicate that the germ or. virus may enter the system of the foetus while in ths womb ; also that it may gain access during the act of being born. The possibility of, the former has not yet been established, while the probability of the latter is very great. Whether contracted in the -womb or during the act of parturition, or subsequent to birth, there is ample reason for 'believing that the germ usually enters the young animal at the navel. It may be taken foi granted that in the great majority of cases, if nob in all, this disease is due to the entrance, by the navel, of germs, which become distributed through the system, and get up the changes on which the symptoms and consequences depend."

In endeavouring to obtain correct views of the nature of this affection^it is important to remember that at birth the cord passing through the navel is made up, among other matters, of vessels, which in the womb -carry the nutritive blood from the mother to the fetus, and the used-up impure blood from the fetus to the mother. At birth this cord is severed, and the blood-Sow stepped by a clot which forms in the vessels. Soon after separation the end of the cord shrivels, and the aperture through which it passes heals up. The extremity of the cord in the navel dies, and under favourable circumstances becomes absorbed. Conditions which favour the absorption of the dead part hasten the closing of the navel, so that in the healthy new-born animal there is a natural process to prevent the entrance of injurious matters through it. It is well known to physiologists and pathologiste that anything which retards the natural healing process favours the growth of microbes there, and o fiords a means fov their entrance into the blocd vessels, wliich distribute them through the sj T stem. It is impoitant, therefore, in view of the evidence that the germ of this disease enters through the opening, to 1 inquire into those circumstances which interfere with the natural disposition of the navel to heal. In all probability anything which, during pregnancy, debilitates the system of the mother may have this effect. Improper feeding, insufficiency of material, essential to the nourishment of the fetus, and especially anything which causes the birth of the young animal considerably before its time must be regarded with suspicion. "Malignant parturient fever of ewes and cibortion in mares are sometimes so closely related ' to joint ill as to suggest its dependency on the same cause. In one very important outbreak of joint disease in foals it transpired that a large number of aboruons occurred in the stud in the s?me reason, and that the abortions in mares preceded the appearance of the disease in the foals. Thus, at least, abortiou is of a contagious nature, being caused by a germ which enters the mare ; this same germ on entering the foal induces in it joint disease. The fact of the malady almost exclusively occurring in the very young, and the relation of the diseased navel to abscesses found in affected carcases, indicate thai; the common mode of entrance is by the umbilical cord. Poft mortem examination makes it clear that the germ usually settles at the navel before it is closed, and grows and multiplies in Ihe clot at the broken end of the vessel. It is then caYricd away by the blood-stream, and distributed to various parts of the system, amongst other places particularly selecting the joints. 'Hie appearance of the disease in a larger proportion of males than females (70 out of 100 cases are said to be in males) - suggests that' the urine which is dribbled by the male interferes with the healing of the zi'wei.

_-is implied by the majority of names given to the affection, the more prominent symptoms are associated with the joints or the navel. Before swelling in these situations is appreciable, it may, however, be noticed that a few days after birth the young animal has great difficulty in moving, is more or less lame, and manifests indisposition to move by constantly lying down or standing in one position. Dd'j'ility

is evident, sucking is not carried oufc vigorously, or continued, and the little subject is tucked up, the coat becoming dry and j harsh, There is often a slight discharge from the eyes and nostrils.* The navel is generally swoolien, open, and discharging matter, and though sometimes it is healed on the outside, its neighbourhood is inflamed. In the course of a few days at some of the joints or other external parts there are noticed hot and painful spellings, which assume a considerable size. Any joint may 'be affected, but it more frequently happens in the hock, stifle, or knee. In lambs, more rapidly than in calves or foals', it becomes evident that abscesses' have formed, which -sometimes burst and discharge a peculiarly unhealthy looking material. Tne loss of flesh is very marked at this stage. From the . commencement the breathing is hurried, and with the progress of the disease it becomes more and more disturbed, shorter, quicker, and sighing. Occasionally in the early stages diarrhcfia is a prominent feature. This, however, may not make its appearance until the disease is advanced, but sooner or later is observed in most cases. As a rule, the symptoms are manifested from 7 to 20 days after birth, and the disease runs through its course in from 7 days to three weeks. Sometimes, however, tne patient dies within three days of its Voeing noticed to be ill. In such cases the symptoms are acute, and death may occur .before abscess formation at the joints. The course may be prolonged, and some subjects '"hang fire" for months, though this is the exception. There will naturally be variation of the symptoms, dependent to a great extent on "the parts involved in the local changes set up by the germs after entering the body. < I On post mortem examination there is generally discovered evidence of the disease having resulted from affection of the ' navel. Though usually open, this may be found healed up on the outside. On the inside, the vessels frequently contain very dark blood, and unhealthy, sometimes putrid matter, and about the end of the cord abscesses may have formed. In calves and lambs most commonly through the veins, and in foals through the arteries, the germs have been distributed to various parts of the body, and becoming arrested in some, set up inflammation and formation of matter tliere. In all very young animals the joint* would appear particularly favourable to these processes, and in animals dead of this affection are found in and about the joint sacs collections of matter, and evi,dence of destruction of essential parts of the joints — the lining membrane which secrets the "joint oils," the cartilage covering the end of the bone, and the bone itself. Sometimes the quantity of matter is very great,* and, bursting through the structures enclosing the joints, finds its way into the sheaths of the tendons, etc. Any part of the body may give evidence of a similar process : the lungs, the chest cavity, the liver, the kidneys, the glands, the cavity of the sJbdomen, and the brain are common ' seats of abscesses. The treatment of contagious disease involves the consideration of curative and preventive measures. Clinical experience and I the nature of this affection tells us that curative treatment is not, hopeful. After entrance of the poison into' the system, de- \ spite the adoption of all known agencies, a ' large proportion of the affected will die (of j lambs and foals probably more than 60 per ' cent.) ; while of those which survive many '' I will onljr drag on an unprofitable existence. ' Treatment of such entails much croi<lole and I expense, and rearing is rarely economical. • j If the subject be a lamb or a calf, the con- j fetitution is usually so affected that only a ' poor specimen is produced ; if a foal, in ad- \ dition to the foregoing the permanent damage to the joints often so interferes with movement as to render the animal unsightly and useless for life. A very small propor- ' i tion, however, get the disease in a mild form, and make a tolerably satisfactory re- ] covery. In the case of foals, it will be de- jj sirable to engage the services of a veterinary surgeon, for each individual case will call for treatment special to its circum- ' stances. Occasionally, an unhealthy condition of the coid or navel and a collection of matter there may 'be discovered before ' the germs have been distributed through ' the system, when local treatment by reniov- j ing diseased parts and killing the germs may avert further mischief. It may also happen that the secondary swellings are in a non-essential part accessible to the knife, when opening of the abscess, discharge of , its contents, and disinfection of the cavity, | associated with attention to the navel, may be followed by good recovery. This treat - j ment, of course, calls for all the skill of the expert, and even with it a successful issue is not common. Once the morbid condition is thoroughly established in the body a cure is not likely to be effected.

While P-rofessor Penberthy credits curative treatment with a very restricted mcaj sure of success, he firmly maintains that joint ill is easily preventable. This aspect of the question will be dealt with in an article >to follow.