PULPY KIDNEY.

Auckland Star, Volume LIX, Issue 236, 5 October 1928, Page 15

PULPY KIDNEY.

PREVENTIVE MEASURES.

RESEARCH AND EXPERIENCES. (By H.8.P.) We are now at that time of the year when the disease known as "pulpy kidney" usually takes its toll of the most forward lambs in the flock and farmers are anxiously watching their stock for the first signs of its presence. Even in the North Island, where pulpy kidney losses are not nearly so severe as they are in Central Otago, the losses front this disease are by 110 means inconsiderable, for it is not unusual for a farmer to lose five per cent and even more of his lambs and it must be remembered that these arc always the best-grown and most forward conditioned lambs of the drop. Over-Nutrition Theory Disproved. For many years this trouble has been with us and until a couple of years ago the Department of Agriculture contented itself with expressing the opinion that the cause was over-nutri-tion, recommending as preventive measures that the ewes with their lambs should be moved to more scanty pastures and that the lambs should be subjected to two dockings, the idea of this latter being that the pain, combined with the attendant blood-letting, would put the lambs off their feed and so prevent overnutrition. A certain southern doctor, who interested himself in the matter at the instigation of a number of farmers there, asserted that he had found the cause to be oxalic acid poisoning, the result of the roving lamb nibbling sorrel at a certain 6tage of its growth. It is sufficient to say that all these theories have been disproved either in part or in whole, and as the result of very considerable research in the South Island especially, we have not yet arrived at any certainty as to the cai|jte. Theories Now Held. At the present time the general opinion held in New Zealand is that the trouble is largely digestive, intensified, perhaps, by some mineral deficiency in the soil and grass and hence in the ewe's milk, which prevents the sound development of the kidneve. They are thus unable to cope with the waste products which it is their work to eject from the system. There is another theory held in England, where research into the cause of this disease has been undertaken at the Institute of Animal Pathology, Cambridge, but this will be referred to later. Effective Preventive Measures. At present though the cause of the trouble has not been definitely discovered, some quite effective preventive measures have been employed, and it would be well for farmers where this disease appears to follow these out promptly. The first method successfully employed was to exercise the ewes and lambs daily, either by moving them from one paddock or block to another, or by driving them quietly from one end of the paddock to the other. By giving the stock this exercise deaths were reduced in three instances from 9 per cent to 2.V per cent, from 6 per cent to 3 per cent and from 10 per cent to 4 per cent. This method entails a considerable amount of time and labour and an equally effective but less laborious method was subsequently employed. This system entails the construction of a temporary holding yard in the corner of each paddock, containing ewes and lambs. Into this yard the ewes and lambs are mustered every fifth or sixth day and are left there for 24 hours. This yarding should commence when the oldest lambs are ten days old and should continue until all risk from pulpy kidney is past for the youngest. In the event of a ploughed paddock being available, this serves equally as well as a temporary yard. The idea is that the weekly mustering gives the lambs the necessary exercise, which keeps their bowels and internals generally in good order and the fast for 24 hours gives the digestive and other organs a much-needed weekly rest. Losses Effectively Seduced.

Many cases where this yarding was followed the losses were entirely stopped in some cases and in others reduced to 25 per cent of those occurring in unvaried mobs on the same farms. Further, it was found that these yardings and mueterings did not in any way check the growth or condition of the lambs. Cambridge Theory—Excess of Protein. The research at Cambridge previously referred to has led the investigator to believe, from the very forward condition of the affected lambs, from a knowledge of their feed and from the wellknown clinical fact that excess of protein is injurious to the kidneys, that pulpy kidneys may be due to an excess of protein food. Mobt of the pastures where these deaths are occurring have been laid down in grass varieties and clovers very rich in protein and it is quite possible that this may be found to be the cause, especially as the deaths occur only in the early spring, when clovers are abundant and the young grass is known to be rich in protein. ' j As a matter of fact, a case which came under the writer's observation supports this theory. A considerable number of lambs were dying from pulpy kidney on short, sweet pasture, which | contained abundance of clover, and the owner in desperation turned the ewes and lambs on to a crop of oats which had been used as winter feed. The deaths ceased at once. The oats, of course, would not have nearly such a high protein content as young grass and clover, besides which their laxative effect on the lambs' bowels was probably beneficial. It is improbable that where there is strong, rank spring growth of grass as there is throgghogt-roiost of the North Island this jfeiwdnj the deaths from pulpy kidney will, be so prevalent as in drier and more sunshiny springs, for the pasture will naturally not be so rich in protein. However, it may be necessary for every farmer to keep a close watch on his lambs, and at the first sign of this trouble yard.them as recommended by the Department, or turn them on to rank feed, where the protein content will be low compared with the carbohydrates.