PULPY KIDNEY IN LAMBS.

Otago Witness, Issue 3889, 25 September 1928, Page 12

PULPY KIDNEY IN LAMBS.

ITS SYMPTOMS AND TREATMENT. , A A\ O r r a ago ’ Mr Dudl ey A. Gill, r' xi ‘ e assistant officer-in-charge of the Wallaceville Veterinary Laboratory, gave a very interesting and instructive address from 2YA on that fatal comPlamt, which affects the best lambs of the nock, known as pulpy kidney, or renal congestion. X started off by saying that this trouble affected lambs that were about three weeks old and caused death so rapidly that it was seldom that a lamb was seen while it was ill. All the owner generally noticed was the dead lamb lying in the paddock.. Twin lambs were not immune from this condition, particularly in some districts, but in the North Island it was nearly always the single lamb in great condition and growing-rapidly that was the victim. The losses occurred, moreover, only on rich country where the ewes ‘ did ” their lambs very well. The disease was not found on hill country, except on low hills where the pastures had been pushed on with top-dressing. When a lamb had died of this disease, and its carcass was opened, the kidneys were usually found to be broken down. Instead of being firm, the investigator would find that the. outer portion was reduced to a soft, jelly-like consistency, from which condition the disease derived one of its_ names. Another point often voticed in these cases was that the sac, in which the heart lay, contained quite a large quantity of yellowish fluid, sometimes so much being present that the sac was tightly distended with it. “To-night,” said Mr Gill, “I want to direct your attention, more particularly, to the means at your disposal for preventing these losses, but, before passing on to that, it will be useful to say a little about the cause of the disease, as far as we know it at present. You will then be in a better position to understand the principles of the preventive measures that can be used. “As I have already said, it is the very advanced lamb of three or four weeks old, that is most liable to attack, and, while lambs up t 6 about six weeks and ones ■as young as 10' days occasionally die from it, this is quite exceptional.

The age, then, at which they are attacked, corresponds to the time at which they start grazing, and, as I have said," the losses usually occur on rich pastures! generally composed of ryegrass, white, clover, suckling clover, etc. Now, these extra-forward lambs have had an abundance of milk from their dams since birth, and, when they start grazing the rich' pasture as well, a very great strain is thrown on their digestive organs, because! whereas it has been called upon to deal with milk onlj-, it now has to tackle herb! age as well, and that means far more than just so much extra food. It is extra food of an entirely different character from the sort the stomach and intestines, have hitherto been accustomed to, and the lambs have to alter their methods tq meet the new situation that the changed diet has brought about. I think you will realise from this how it is that a lamb whose digestive organs have been fully occupied from birth with large quantities of milk sometimes makes a mess of it when it tries to- take ryegrass, clover! etc., as well. “All food substances are very compli: cated chemical mixtures, and, when one speaks of a food being digested, one means that it is broken down into a number of much simpler compounds which the body can absorb from the intestine and use for building up its tissues and supplying it with energy. But when thiq breaking down process is not carried out properly, substances are apt to result—! largely from the activities of the microbes) w-hich are always present in the intestine —which, instead of being useful to the body, are actually poisonous to it, and this seems to be what happens to the lambs which die so suddenly. These poisonous substances are continually being formed in any animal, but only iq small quantities, and the liver, in these circumstances, is able to neutralise then) before they can accumulate sufficiently to do any harm. In these lambs, owing to" the fact that, through improper diges-r tion, they are being formed in larger quantities than usual and also because the liver is already fullj’ occupied, they accumulate, till, if steps are not taken to check the lamb, they poison it and cause very rapid death. “ I hope that what I have said has been quite clear to you, because it is on that, especially in the latter part, that prevem tive measures are based. These all aim at helping the lamb to throw off those poisonous substances until, through its becoming accustomed to digesting the milk and pasture combination, the danger period is over. “ The general experience here in the North Island is that ‘ marking ’ the lambs —that is, docking and castrating them—is an effective preventive measure. No doubt it acts well here, because the ten. dency to the disease is not so great as it is in some other parts of the Dominion, and the exercise involved in yarding them up, together with the fact that they miss a feed or two, and lose’ some blood, is, enough to stave off the disease. “To be most effective, marking must be done at the proper time, that is to say, when the lambs are approaching three weeks of age. It should be quite obvious to anyone accustomed to lambs that, if marking is done much earlier than that, the check it gives them has been entirely overcome by the time they reach the dangerous age, and therefore it is not likely to prevent the trouble. It is best to draft the ewes into mobs as they lamb and then mark each mob as they reach the right age. If this cannot be done from lack of paddock room, then the younger lambs should be missed at the general marking and dealt with after, when they have reached the required age. “In Central Otago, where there is a great tendency to this condition, it has been found that, marking is not of the same use as it is in the North Island, and, last year, the Department of Agriculture’s veterinary service organised some experiments in that district to try out various other preventive measures. Research work is iroing on there, and is still continuing at the Wallaceville Veterinary Laboratory into the more technical aspect of the disease, and the experiments referred to were run in conjunction .with it. Of the different methods tried I will only mention those which gave good results, and do this because, after the extraordinary winter we have - had, the ewes are coming in in excellent condition, and it is likely, that there will be a good deal more of this trouble among the lambs this season than is usually the case. Moreover, now is the time when farmers who are liable to get these losses should be organising their flocks to meet it and preparing to put preventive measures into practice. “ We found three methods which could be used with very good results. They all have one thing in common, that is, to put them into effect properly, the flock must be drafted into mobs at lambing, so that lambs in any given mob are approximately the same age. It stands to rea« son that one cannot handle sheep as they need to be handled to prevent this disease if lambs three weeks old down to ones newly born arid ewes still to come in ’are all mixed up together

“ One method of prevention is by daily exercising the lambs from the time they are about ten days old. , “ The following example will show you the effect of exercise: — “Farm 1. —Exercise mobs (800 to 1000 lambs), deaths 24 per cent.; unexercised (100 lambs), deaths 9 per cent. “I 1 arm 2.—Exercised mobs, deaths' 3 per cent.; unexercised, deaths 6 per cent. “ Farm 3.—Exercised mobs, deaths 4 per cent.; unexercised, deaths 10 per cent. “ The way in which the exercising was done was neither consistent nor particularly thorough, but is the best that can usually be managed at such a busy time of the year. It consisted of driving tlie sheep from, end to end of the paddock with quiet dogs for a varying time each day. Some days a good half-hour might be devoted to a particular mob. whereas next day only enough time might be available to drive them once up the paddock. In spite of this, however, the cases quoted are fair examples, and they certainly show a considerable saving in the losses. The object in exercising the lambs lies in the fact that the bowels are stimulated to act more effectively, and thus the body is helped to discard its waste products more expeditiously. “ The second effective method tried was to place the mob on ploughed ground very early in the morning, as soon as it is light, and leave them there for three or four hours. This acts in much the same way as the exercise. The ewes go on the ploughed ground -hungry after their night’s sleep, and consequently wander about looking for food, taking their lambs with them. I can give you no definite figures on the results of this method, for the experiment was not under my supervision, but I know that the results were extremely good. “ The third and last preventive measure that gave good results is one that worked perhaps better than exercising, and, moreover, is the most practicable and easy to work. It consists in yarding up the mob in a corner of the paddock, that has been fenced in with a few standards and wire netting. They are left in this yard for a period of 24 hours, once a week, from the time the lambs are 10 days old. One farmer who gave it a tentative trial two seasons ago on his own initiative consented to test it thoroughly last season with an adequate control. His results, which speak for themselves, were as follow:-— “ His mob oi 434 lambs was divided into two equal lots; one lot was yarded for 24 hours every seventh day; the other lot was not yarded. Deaths in yarded lot, 4 per cent. Deaths in non-yarded lot, 3 per cent. “Out of 160 twin lambs (80 pairs), eight died. He then yarded the lambs for 24 hours. One was found dead in the yard and none died afterwards. “ Out of some 1900 lambs, his total loss was under 30, and of this total, fifteen died out of 377 that were not being yarded. Thus, the average death rate over the whole flock was less than 3 per cent. The death rate among the yarded lambs approximated 1 per cent., and that among the unyarded lambs was approximately 4 per cent. Reckoning a lamb’s value'at the moderate figure of £l, a saving of 3 per cent, of lambs in this mob of 1900 was equivalent to £57. It is a noteworthy fact that the deaths among the yarded lambs occu.red either in the yards or just before yarding. It would appear from this that an interval of seven days is possibly too long and that about five days would be better. “ Another farmer had nine lambs die in a certain paddock. He was then persuaded to yard the mob for 24 hours. No more deaths occurred here for eight days, when one was found sick and died laten The lambs were then yarded again, and no more died. In another paddock where a heavy death rate occurred last season three" lambs died. The mob was then placed on a ploughed paddock for 24 hours, after which the deaths stopped. “ One more case is worth quoting. A farmer who had lost 16 lambs out of opproximately 270 odd, was of the opinion that nothing would check the death rate, but as he happened to have a ploughed paddock handy he agreed to put the whole mob there for 24 hours. Only two more lambs died, after this was done.

“ This method is practicable on nearly every farm where losses occur. .It is easy to put it into effect, and has the great advantage that neither ewes nor lambs show any noticeable check as a result of the treatment. They are put in the yard in the morning, say, about 9 o’clock, and are left there until the same time on the following day. As a result the lambs miss a good deal of milk that day and their bowels become properly empty, ready to make a fresh stirt the following day. For the method Io be really effective, they must be sufficiently tightly packed in the yard to prevent the ewes from feeding. “ Apart from these preventive measures that I have mentioned, the practice of flushing the ewes before they lamb—that is to say, giving them a run on to succulent green feed, such as green oats, for n time —is of benefit in helping to avoid these losses. In fact, such a period of flushing should be regarded as a normal and necessary practice in' sheep husbandry. “ I may as well mention that, in adition to technical research work on this lamb disease being continued, the department’s veterinary staff in Otago, South land, and Canterbury is experimenting this coming season with a variety of mineral salt-licks to try and counteract the tendency to this disease, which, it is thought, may possibly have some connection with the balance between the various minerals required by the growing lamb at that particular stage in its life.” _ At the last annual conference of the New Zealand Veterinary Association in Wellington, Mr Gill put forward a new theorv regarding this disease which was well received.' He stated that while still regarding the primary cause as nutritional, he had formed the opinion that certain bacteria normally present in the large intestine might be responsible for setting up the toxic condition which caused death. He had found these bacteria present in the small intestine where they would be in a good position to exert adverse chemical changes on the passing food, and the products resulting from those changes would be far more easily absorbed than from the large intestine. Assuming that such products were ci a particular kind, which was very pro-

bable, then all the post-mortem lesions usually found and all such ante-mortem symptoms as were sometimes observed, could be readily accounted for.