BEWARE THE CURE!

Evening Post, Volume CXVI, Issue 80, 2 October 1933, Page 16

BEWARE THE CURE!

-lODIMTIS'*

WGHT IN RIGHT PLACE

INDISCRIMINATION BAD

? While deficiency of iodine causes joitrej it does not seem to be the only ,'c;ausc of goitre; and. goitre in itself is not ovidenco that one must rush in -with "iodine. i ' 'Further, among farm animals the indiscriminate use of iodine "is not to ,iie encouraged" unless. an iodinb de•lieiency is definitely known to exist. -Colonel McCarrison and X.,13. Madliava, working in India, state that the causes of goitre are many and include hereditary, physiological, psychic, nutritional, and Hiicrobic influences. Goitre may occur under conditions of insaniUtibn and badly balanced diet, or ot ■vitamin deficiency. Too much lime, i-abbage, bran, inaizoy and possibly cerlairi cereals may all have a goitrogeme action. There are goitrogeme agencies, '•and there are antt-goitrogonie agencies; oVery one of the latter may not be effec- ■ live against each one of the former. • VtO GOITRE IN WAIBABAPA 1 , SHEEP. • This 'work in India is summarised .is a paper read recently before the ■New>Zealand Instituo of Chemistry by Miss E. M. Mason, M.S.C., of the Department of Agriculture Chemical 'laboratory. Miss Mason told how, in 'New Zealand and Australia investigation is being carried on, regionally, fimong farm animals. Sheep bred and i.ed on alluvial soils in Southland have .sheen found to, have thyroid glands greatly enlarged and extremely deficient in iodine. But in Wairarapa not Jone case of goitre was found among feheep. . !':.The Department's method is'to collect numbers of glands from sheep ' itnd lambs all over the region-under test, together with details regarding Conditions of climate, soil, etc., under Svhich they yrcxe reared. This work is ;\>ased on.. the assumption, that- tho ■'amount of iodine an animal has at its iJlisppsal for nutritional purposes is rcirftected-. in. the thyroid gland, and that if /the amount falls below a certain minifmum value, enlargement of the gland Will follow. In New Zealand so far -.'JtUree districts have been completed in '.detail—the Wairarapa, Otago, and ,:'•■• . • :/ Miss Mason stated that "the main factor influencing the distribution of .iodine in the thyroids of lambs from the fjAVairarapa district appears to be the Isoil. formations, of wlich there are four main, types .corresponding to the underlying rocks,:-which njay be loosely described, as limestone, greywacke, papa, ;and alluvium—these in order of deceasing iodine in the gland. The alluvial.soils are the lowest, and swampy poilsj irrespective of geological formation, are the richest in iodine. : lODINE FED WITHOUT GAIN. • ."Not, one case of goitre was found .Hi*., this district, and an experiment car'hied out on'a farm on. alluvial soil -bibrinatioii, on the feeding, of iodine to did not reveal any advantages hvhatsoever; hence it is concluded that {supplementary iodine feeding in the [Wairarapa is not required." Indeed, indicated elsowhere in the ■tjiaper* there is a possibility—not yet proved to finality—that feeding of iodine' where there is not iodine-defi-Viency may cause-1 goitre. "The case of Southland is different. Sheep bred on alluvial soils there have 'glands often greatly enlarged and ex'tromely deficient in iodine. This soil , ;.,£b a light -typo -with a gravel substrata ■£tnd is subject to a constant and fairly fiieavy rainfall with the result that a great deal of the soluble salts including {iodides must be leached away. Thus it (follows that the pastures will be low in ,fodine, and sheep grazing hero will be /unable to obtain an adequate supply in ithe normal manner, so that asuppleiment of iodised tlalt would almost undoubtedly have beneficial results. The i^reywacke type of soil is not as heavily Reached as the alluvial, but even so is .^onsiderably lower in iodine than that pt the Wairarapa. . I _ _ "The main soils of Otago are schist > Vr derived from schist. Here the annual Rainfall is very small and in some parts, jrfrpught conditions predominate. Here V.f .course no leaching action can take jiilace; in ,fact, iv places solublo, salts fire, exuded; from the earth, and form jtlcposits which are readily eaten by ptock. i. Some of these deposits contain ji<3atively large quantities of iodine, ■/ri'oitre is.npt entirely absent from the fcheep in- this district, odd cases occur :I hroughout Otago, more particularly tofcvards the.East Coast, but the average Soclinc content of the thyroid glands is pyno means deficient, and approximates that jbf glands, from the Wairarapa. NEED FOB CAUTION. ■■• ''New Zealand has always popularly 1 sen known as an iodine deficient eoun-h-y,. hence has had her share of. 'iodine propaganda', with the result l hat all over the country farmers have I icen feeding' iodised licks whether ■jiheir stock require it or not. In.some ti-ases, even they Wive: been iodising hbemielves. Evidence has been ob'jl aimed that the feeding of iodine when jit is not .deficient may actually cause coitre, but.the evidence is as yet not fimclusive. lodine is an. element that •as. required only in the most minute (Quantities. Stock are 'usually given it |at the rate of.a few ounces-por ton of >;bmmoß nalt. There is no real proof h hat under normal conditions it improves the fleece or increases milk ' bne>l&, butterfat output, etc., bo. that, Jnceepfc where a deficiency is definitely iiTjown- to exif<t, the indiscriminate use yf. iodine is not to be encouraged." Investigation in. Australia", though 'Australia is popularly supposed to bo Jk4 iodine-deficient country, has so far VAownno trace of this deficiency. "The j^Unds are all small and contain an £frnount of iodine very much above the moiiting; value. •'' ' 'Speaking generally, Miss Mason finds [Chat "the idea that goitre is due to \f, deficiency of iodine has become so jfirmly fixed in the minds of the people jfliat it has provided quite a serious wifcumbUng block to the advance of knowledge of the conditions under .'which the gland may become ijabaormal,"