Cobalt Gave Mainly Weight Depression

Press, Volume C, Issue 29554, 1 July 1961, Page 6

Cobalt Gave Mainly Weight Depression

In general the trials < eondvcted by the Depart- t went «t Agriculture have t shewn • RenMMten In 1 live-weight gains to cobalt ’ treatment. . Mr T. G. Robertson, bio- J metriaiah of the department « in Wellington, told the Msssey College sheepfarmers' con- s ference this week that no 8 large-scale areas had been j discovered where a cobalt ] deficiency occurred that were t not previously known. Many i of the areas which had been : known to be cobalt deficient t in the past now appeared to i be no longer deficient Over i the years a considerable • amount of cobalt had been j applied in these areas and ; the deficiency had been over- x come, at least temporarily, t But cobalt did not stay in t the soil. It leached out and any balance now reached was i probably a pretty precarious c one. t This series of trials did. x however, show that there t might still be small pockets 1 where a cobalt response could x be obtained. There had been x one spectacular example of.v this this year at Matamata j r The cobalt treated animals d gained 191 b over two and a t half months while the un- v treated animals gained only • 51b. Commenting on the incidence of a small, but fairly general depression in live-i weight gains to cobalt, Mri Robertson said it had been | suggested that this might be ; due to the presence of the bullet itself and that the

effect might not show up if the cobalt was supplied in other ways. On the other hand, in a group of trials which compared cobalt given as a sulphate drench with the bullets, depressions of about the same size were shown. While this did not necessarily mean that farmers should stop applying cobalt in any form anywhere, Mr Robertson said it did mean that it should not be applied indiscriminately to the animal as a drench or bullet. Further work was needed to look at the effect of applying cobalt as a topdressing. "In the meantime I think a good rule would be to have a talk to your local farm advisory officer before starting to use cobalt on your farm for the first time.” Copper had been included as a treatment in a number of trials. In a few cases there were responses in weight gains and one or two trials showed depressions. I Most showed no effect. It; was known, however, that! weight responses to copper were rare. Responses to cop- 1 per drenching, where marked ( deficiencies occurred, showed up in other ways such as in wool quality.