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At Tokoroa, which is situated on pumice soil affected with bush sickness, the average butterfatproduction per cow has shown a remarkable increase as a result of the relative using of limonite lick. On one farm the following Jesuits were secured : — 1931 1932 (No Limonite). (Limonite). September . . .. .. 17 lb. per cow. 32 lb. per cow. October .. .. .. • .. 24 „ 45 It has been found that not all forms of limonite give satisfactory results. Up to the present time that secured from Whangarei, provided it is sufficiently finely ground, has given consistently good results. Sheep Experiments. The sheep used in the experiment at Atiamuri have continued to respond very favourably to the limonite treatment. Ewe hoggets reared in 1931-32 developed into perfectly grown specimens and yielded, on the average, 11-5 lb. of good-quality wool. The mothers of these hoggets, after rearing their second lot of lambs, were killed for consumption, and provided dressed-carcass weights ranging between 80 lb. and 98 lb. In an experiment in the Kaharoa district, where the soil was of a character which rendered it particularly bad as regards the incidence of bush sickness, thirty limonite-fed ewes, which were mostly broken-mouthed and had failed to rear any lambs the previous year, in the following season developed excellent condition and reared 100 per cent, of lambs, the wethers from which averaged, when dressed, about 32 lb. The ewe lambs are being retained for breeding purposes. A comparative line of ewes kept on the same farm, and not treated, have shown a 90-per-cent. mortality, and their progeny suffered a still higher mortality. Instances may be quoted of the successful use of limonite in areas bordering the distinctly bushsick areas. At Putaruru a farmer who in 1931-32 was able to send only 600 out of a line of 3,000 lambs to the freezing-works was able, after he adopted the limonite treatment in the following year, to send all his 3,000 lambs away fat. The cost of treatment for the entire flock, ewes and lambs, was under £20. Further reports of the good results attaching to limonite treatment have been received from the Bay of Plenty and Gisbornc districts. In these cases good results are appearing where the lick has been used for stock which were not definitely liable to bush sickness. One of the drawbacks of the entirely efficient use of the limonite salt mixture is attributable to the spread of ragwort in districts affected with bush sickness. In these instances the toxic effects of the ragwort outweigh the benefits of the lick. Consequently trials are also being conducted with various sprays, in particular with ammonium thiocyanate, as a means of combating the ragwort menance. Mairoa Experiments. Stock experiments in the Mairoa district, where " dopiness " was prevalent and attributable to lime and phosphate deficiency, were brought to a conclusion. Briefly, the results of the experiment showed that sheep grazed on a plot which had been treated with 40 cwt. carbonate of lime plus 4 cwt. superphosphate per acre stood out well above others in appearance, being healthier and stronger, their average increase in weight over the period of the trial being 32 lb. Other treatments consisted of 5 cwt. of lime plus 2 cwt. of super and 3 cwt. of lime plus 2 cwt. of super, but with these lighter dressings a certain amount of unthriftiness appeared. The conclusion was reached that the Mairoa type of soil required both lime and phosphate, with a considerable excess of lime, in order to secure maximum healthiness. Morton Mains District Southland. Deficiency diseases have also appeared in this district. The use of the limonite salt lick has, however, given good results, and it has been possible to secure drafts of fat lambs from flocks which have been given access to this lick while grazing on those blocks. Analyses of the pastures grown in the district have shown them to contain a high content of manganese, and it has been thought that this element may play some part in withholding the iron from being assimilated. Metabolism Experiments with Sheep. These have been conducted by Dr. I. J. Cunningham at the Wallaceville Veterinary Laboratory. Investigations have been directed to test the supplementary value of various calcium and phosphorus containing materials, these being fed to supplement a basal diet of poor-quality hay. The conclusions reached may be summarized as follows : Lambs fed a hay of low nutritive value, deficient chiefly in phosphorus and protein, showed positive calcium balances, but negative balances of phosphorus and nitrogen. Supplementary feeding of potassium phosphate decreased the calcium balances to a negative value. Supplements of dried blood enabled the animals to retain nitrogen and at the same time improved the retention of calcium and phosphorus. The calcium and phosphorus balances were not improved by feeding Nauru rock phosphate as an addition to the hay and driedblood diet. The work, though only preliminary in nature, suggests that sheep feeding on a pasture similar in nature to the hay used (e.g., high country or drought conditions) will not benefit by supplementary feeding of mineral mixtures to the same extent as they would by improvement of the nitrogen intake.

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