Growth Rate Depressed By Cobalt And Copper

Press, Volume XCIX, Issue 29378, 3 December 1960, Page 8

Growth Rate Depressed By Cobalt And Copper

COBALT and copper have been responsible for a depression in the growth rate of young sheep in trials conducted by the Ashburton Veterinary Club. For six months from the middle of last March a group of ewe hoggets was given copper and their progress was compared with a similar untreated group of sheep. All of the hoggets were in first-class condition when the trial started and there was no question of ill-thrift in them. In the six months the copper group put on an average of 271 b while the untreated group gained 341 b. At that stage it was quite apparent which sheep had been treated. Ilie hoggets had been shorn in January and when they were shorn again in October the

treated group clipped an average of 6.81 b, compared with 7,41 b for the controls. On another property the club obtained similar results. In another trial where lambs were treated with cobalt over a period of 92 days from last January there was a 42 per cent, depression in the growth rate of the treated lambs. A club spokesman said it was often assumed by farmers that treatments of stock or pastures, even if they did not do any good, would at least do no harm. Here, however, were two treatments that had had an adverse effect on the ability of stock to grow, and if it was a waste of time and money doing something that did not give a return, then it was even more so if an actual loss was involved. In the light of these experiments it would be prudent for farmers to evaluate critically what they did. This meant a trial in which half a particular group of animals were given the treatment and these were compared with the untreated animals on the basis of weight gains.