MANGELS FOR STOCK.

Dominion, Volume 5, Issue 1271, 28 October 1911, Page 8

MANGELS FOR STOCK.

THE MORTALITY QUESTION. In a preliminary note in the. .latest issue of the "Agricultural Journal,'" Mr. B. C. Aston, referring to the matter of the mortality of stock on mangels reported last month, says:— "The samples of mangels referred to in ths last isiue were analysed during September, when, in spito of having been kept for several weeks after the. mortality had occurred (early in August), there was found te be a greater amount of nitrogen as nitrates and nitrites than was found by ProfessoT Wood (Cambridge) in November, seasonable with May in New Zealand. Wood found 0.013 per cent, nitrogen as nitrates (Jour. Roy. Ag. Sec. Bag., IS'JS, p. 535). Tho juice of ths Waitotara mangels coataincd p.Oli jer oei.t.—the average of sovsn roots examinod—of nitrogen as nitrites and nitrates. Nitrites are present in traces, a fact which seems not to have been recordrd before in mangels, although mentioned as keing found in other plant-juices in small amounts (Watts's Diet., Morley and Muir, Vol. iii, p. 567). The amount of nitrogen found is equivalent to 0.43 per cent, of potassium-nitrate, and a cow eating COlb. of mangel-juice would consume 116 grams (40z.) potassium-nitrate (mangels contain 95 per cent, of juics). Finlay Dun ("Veterinary Medicine") gives 1.20z. as the medicinal dose for cattle. Hazard found that largo doses killed cattle (Nunn, Veterinary Tor.icology). "The presence of nitrites must, however, be considered, as they are far more toxic than nitratesi' It is-believed that the toxic action of .'nitrates is. to be partly explained by their -reduction to nitrites, and circulating in the blood as such (Wyuter Blyfch "Poisons"). The medicinal dose of sodium nitrite for cattle is stated by Finlay Dun to be the same o.i arnyl nitrite (10-1G minims). Sodiumnitrite was found by Barth to be a more powerful poison than sodium-nitrate, less than 6m?s. (0.1 grain), when subcutaneously injected, being sufficient to kill a rabbit of -155.5 grams weight. Rabbits and guinea-pigs refuse to cat tho Waitotara mangels. 1 "Tho investigation is being continued. In tlie-moautimo it will bo sufficient to warn farmers not to feed stock too free ly on mangels; not moro than one-half the dry matter required by stock should be fed to them as mangels. They contain about 10 per cent, of dry matter."