"FOOD IRON"

Evening Post, Volume CXII, Issue 11, 13 July 1931, Page 10

"FOOD IRON"

A SHEPHERD-CHEMIST

STATE OPTION ON IRON ORE

It is one of tho romances of the Twentieth Century that the shepherd must also be a chemist; and must quarry the rock and pass it through his laboratory in order that stock may eat what the pasture denies them.The supply of food iron to sheep in iron-starvation ("bush-sick") districts is the subject of a further article in the "New Zealand Journal of Agriculture" by Mr. B. C. Aston. If food iron could bo successfully supplied to sheep, an enormous area of iron-atarva-. tiou land, now more or less waste, could be used profitably. It is, of course, important that the food iron, should be cheap and that the-feeding should bo cheaply done. Mr. Aston,' as Chief Chemist, has for years been seeking a Now Zealand supply of "an iron compound which might take the place of the comparatively costly double citrate of iron and ammonium for the prevention and cure of bush-sickness." He found that hydrated oxide of iron was being turned out in two places (Onakaka and Whangarei) "as a commercial product which is being used by gas-works in the purification of eoalgas. "It appeared, however, that carbonate of iron would probably be more assimilable by the animal than, the hydrated oxide would be. LOCATING NATIVE IRON ORE. Native carbonate of iron is recorded as occurring at various spots in both islands. In 1926 Mr. Aston identified a largo deposit of carbonate if iron at Huutly. At a clay-pit there he found a large quantity of discarded boulders, which were crushed with difficulty, and the resultant iron carbonate was experimented with by feeding to sheep as a lick. "The Department of Agriculture obtained an option over this ■• deposit, and the option is still in force." That was five years ago. Followed "tho usual delay in getting positive results." Some of th© crushing and grinding appliances were very inadequate. To reach the best crushing and grinding plants meant transport cost. There were certain "objections to the use of this water-insoluble material. It was not till 1929 that encouraging results . began to be obtained, from the use of the material as a lick." In 1930 tho Department of Agriculture was able to report to the Empire Marketing Board that "quite a number of more reliable farmers have been supplied with this carbonate ov iron compound, and nearly all report some good results from its use. In most eases molasses had to be mixed with the salt and iron in the first instance to induce the animals to take the lick, but once accustomed to it the molasses was gradually .reduced until only the salt and carbonate remained . . . With cattle in another district a reliable settler reports having had excellent results over two seasons with carbonate o£ iron, and has used no citrate of iron during all that time, notwithstanding which his stock are all in perfect condition." • A NOTABLE SUCCESS. In tho same report (1930) to the Empire Marketing Board mention was made of "a very extensive experiment with sheep on iron, lick treatment" at Atiamuri. Tho sheep numbered 1600. Mr. Aston now is able to report the further success of that experiment: "On this sheep-run it had never; bofore been possible to raise lambs to. maturity without treatment. The 1600 ewes were allowed full access .to some carbonate-of-iron lick from May, 1930, to November. Forty other owes were selected as controls, and these had no access to the lick. On 14th November, when the controls wore shorn, their I average weight was 96.411b. On the other hand, the. weight of twelve sheep taken at random from the 1600 ewes was 1191b. Mr. Taylor reported on 10th March last that .the forty control sheep, with their lambs, had completely gone to pieces, only eleven surviving; and that three .others"would probably have diecl, but in order to save unnecessary loss to tho owners they were drenched with a solution of iron ammonium citrate and put on a slagged paddock, where their response to the iron treatment was immediate. The 1600 ewes, on the other hand, survived in good healthy condition, and the majority raised their lambs successfully. LESS THAN A PENNY A SHEEP. "Tho efficacy of the iron carbonate mixed with salt as a lick for sheep has so impressed itself on tho minds of the owners that they have purchased a ton of the iron carbonate and ordered another ' ton. As to the quantity roquired, it may be said that on this sheep station 2000 sheep consumed only 16 cwt of-the carbonate in eight months (June to January), or less than lib per sheep, at a cost of Jd each.?' The material that is tints being supplied in the treatment of bush sickness is an extremely floury powder, and when mixed with salt in equal weights tho carbonate -which, when fresh, is of a grey colour, partly oxidises to a brownish colour. , Considerable success in feeding ironcontaining pellets (made by machinery) to sheep (which are educated to cat them), and certain experiments with iron carbonate in ensilage, are features of Mr. Aston's/article. ;