COBALT DEFICIENCY

Wairarapa Times-Age, 5 September 1941, Page 7

COBALT DEFICIENCY

SUSPECTED IN WAIRARAPA AREAS EXPERIMENTS BEING CONDUCTED THIS SUMMER. EXPLORATION OF POSITION. “While I must make it clear that our investigations are not yet complete,” stated Mr N. Lamont at a meeting of the Masterton Young Farmers’ Club, “we do expect that the experiments we propose to conduct this summer will confirm our present suspicions that fairly large areas in the Wairarapa are, to a mild degree at least, deficient in the mineral, cobalt. “Cobalt is a relatively uncommon metal, closely related chemically, with iron and nickle, and it has been found that it is necessary for stock, particularly young sheep, to obtain a certain very small quantity of this element in their diet in order to maintain health and thrift. All are no doubt familiar with the fact that ‘bush-sickness’ has now been shown to be the result of a deficiency of cobalt but it will surprise most people to hear the term ‘bushsickness’ associated with the Wairarapa. “It may now be said,” stated Mr Lamont, “that local Departmental officers have suspected the existence of local deficiency for some time and during last summer a special effort was made to explore the position. This preliminary investigation took the form of a survey of pasture cobalt content with the object of determining what areas, and if possible what soil types, were likely to be deficient so that confirmatory experiments could be planned to good effect. These samples were collected in such a way as to provide us with information relating to all the major soil types in the district although naturally special attention was devoted to localities where farmers’ accounts of trouble led us to suspect a deficiency. “I wish to make it quite clear however,” continued Mr Lamont, “that the analysis of the pasture samples I have collected, are not accepted as final and positive diagnosis, and we are proposing to conduct special experiments this coming summer in order to finally confirm the indications resulting from the pasture survey. I may say, however, that there are at least two intensive soil types in the Wairarapa which have consistently yielded low pasture analysis and where there is also a substantial amount of corroborative evidence forthcoming from farmers themselves.

“These soils are first the ‘brown-yel-low loams’ typical of that stretch of country lying along the foot of the Tararuas from Kaiparoro, through Rongokokako and Nireaha to Hukanui —and secondly, the shingle flats found in the Taratahi, Moroa and Tauherenikau plains. Such evidence as we have at present suggests that no trouble is likely to be found on any type of hill country but there are other areas of ploughable country, in addition to the two main classes mentioned above, where further investigation is desirable. “It is, of course, rather unsatisfactory to be unable to present a final and comprehensive report on this subject but I feel that we know enough already to advise farmers to at least experiment with -cobalt where they have any reason to suspect cobalt deficiency —and certainly this should be done by sheep farmers whose properties are located on either of the two more suspected soil types above. “Briefly, cobalt deficiency—in the Wairarapa at least —is evidenced by rather vague and indefinite symptoms which can hardly be described any more accurately than as a general unthriftiness in young sheep. It is known from work in other parts of New Zealand that young sheep—particularly weaned lambs —are more susceptible to cobalt deficiency than are any other .class of stock. Older sheep are next, then young cattle while there is no evidence in the Wairarapa that mature cattle are in any way affected. Cobalt is, in fact, in no sense a “cure-all” or a tonic and any farmei' whose young sheep thrive satisfactorily through the late spring and summer, may as well forget about it. If lambs go back season after season during the late spring and summer, and fail to respond to worm drenches, etc., then cobalt deficiency may be suspected. “The most satisfactory way for a farmer to determine for himself whether cobalt will be of any use to him, is to select a small average lot —say ten weaned lambs and drench these with cobalt at least once a week for, say four oi’ five weeks. If possible these and a corresponding group of untreated lambs should be weighed, and if as a result of treatment the lambs respond clearly, then cobalt licks and topdressing should be freely employed.

“An essential feature of the treatment of cobalt deficiency is the fact that it must be administered in small but very frequent doses, foi* this reason, drenching is impracticable as a remedial measure although very valuable for diagnosis. Licks are more satisfactory if the stock take to them readily but topdressing with cobaltised manure is the best method of all. Unfortunately, cobaltised topdressing must be carried out annually to be successful but in spite of this it is the most efficient corrective treatment. One hundredweight per acre of cobaltised superphosphate is sufficient, but ..where, as a result of super rationing, even this small quantity is not available, it may be practicable to apply cobalt sulphate to the pastures in some other way. As only about half a pound or less of cobalt sulphate per acre is required, some spreader is obviously necessary. In this connection, although our «knowledge is not yet complete by any means, we must warn farmers that lime may not prove satisfactory as a spreader for the cobalt sulphate and if possible some other substance e.g., sand should be used. Cobaltised manure should also be used for crops at least with those to be fed to sheep during the summer. “In conclusion,” said Mr Lamont, “I cannot emphasise too strongly the fact that cobalt is not a cure-all that can be expected to produce marvellous results for each and every complaint of farm stock. There is, I know, a tendency for a ‘run’ on such a substance as cobalt following a preliminary report of an investigation such as we are carrying out. Except for possibly using cobaltised licks and manure for calf and young heifer paddocks, dairy farmers need not concern themselves with cobalt —and all pur present knowledge confirms this fact. Sheep farmers who have experienced unthrift in young sheep, particularly, on the classes of country mentioned,

are on the other hand strongly advised to experiment with cobalt. “Cobalt sulphate for drenching and cobaltised salt for incorporation in home mixed licks are available from the Department’s office in Masterton. Both Mr Armstrong, our Department’s veterinarian and myself would appreciate hearing from farmers who feel that they are getting results by using cobalt supplements.”