H.—29.

by a conference fully representative of rubber-manufacturers, the milking-machine industry, the Dairy Board, and Government Departments concerned, and they have now been made mandatory. Laboratory and field tests have indicated that, when made in accordance with the specifications and used intelligently, the standard rubberware performs satisfactorily. Investigations are being continued with' a view to effecting further saving, and every effort is being made to assist both manufacturers and dairy-farmers to achieve the greatest possible rubber economy consistent with efficient milking. Bull Sterility.—Tlie semen-testing service was again available at Ruakura. Samples were received from eighty bulls, of which thirteen proved to be sterile and a further twenty-three were of low fertility. Preliminary investigations were made in connection with the assessment of vitamin C in the blood and semen from bulls of low fertlity in view of American results which indicate that this is an important factor in some cases. Artificial Insemination. —In one herd at Ruakura, two yearling bulls were used, and, as might have been expected, the percentage of conceptions was rather low. In the other herd, using a mature bull, fifty-seven out of eighty-six cows (66 per cent.)_ held to the first insemination, and only seven remained empty after the third insemination. As indicated in last year's report, when the dairy industry is ready to organize artificial insemination, a satisfactory technique will be available, • Contagious Abortion.—This year free vaccination of calves with the strain which has proved so successful in America was made available to dairy-farmers, of whom 1,150 availed themselves of the Department's offer, and approximately 20,000 calves were vaccinated. The vaccination was carried out by officers of the Live-stock Division and veterinarians employed by dairy-farmers' organizations using vaccine prepared at Wallaceville. The importance of this problem is indicated by the abortions which occurred last year in the herds applying for vaccination. These averaged 25 per cent, in two-year-old heifers and 9 per cent, in cows three years and over. Parasitology.—lnvestigations into the relative susceptibility to internal parasites of various sheep breeds and crosses have been, continued, as have the experiments with pure artificial infestations of two of the more important parasite species. Phenothiazine is being tested in a number of field trials. Various aspects of the hydatid problem are being investigated in collaboration with the Hydatid Research Officer of the Otago Medical School. Nutrition Experiment at Ruakura. —Investigations into the nutrition of dairy cattle and pigs have been actively continued. A special technique has been devised for studying intake and digestibility in grazing cows and sows. Preliminary trials have been made with the chromium-oxide method of measuring digestibility in these animals. Ergot. Experiments have shown milk and flesh from cows fed ergot in toxic doses to be free from alkaloids, and no ill effects were produced when they were fed to rats or pigs. No importance need therefore be attached to propaganda suggesting that New Zealand animal produce is dangerous on account of ergot consumed by grazing stock. Copper Deficiency in Peat Areas.—lnvestigations have been commenced in areas where "peat scours" in cattle and ataxia in lambs occur. Preliminary work has revealed a deficiency of copper in the pasture, and experiments have been initiated Io deteimine the best methods of correcting this deficiency. Red Cell Characters in Dairy Cattle— The study has been commenced of inherited red cell characters in dairy cattle, recently reported from America, where it is suggested that this work may prove of considerable importance to breeders. Projects arising from Conditions created by the War. —To ensure that New Zealand would not be left without supplies, preliminary investigations have been conducted into emergency methods of preparing insulin, adrenalin, liver extract, and thyroid extract. Biological tests have been conducted to determine the best conditions for growth and harvesting of Digitalis purpurea, which is being grown in New Zealand for medicinal use. Digestive trials have been conducted with New Zealand dried meat. Samples of poison <>-as and camouflage paint have been produced for Army use. Chemical assays have been made of rubber-producing plants grown, experimentally in New Zealand. The survey of New Zealand fish-liver oils has been intensified with a view to their utilization as a source of vitamins, which are known to be in short supply. At Ruakura a large area has been devoted to vegetable-production for the armed forces, and several senior members of the staff have been released for this work. . . , Miscellaneous. —Experiments have been continued concerning bone-diseases of sheep, mangel poisoning in pigs, cobalt deficiency, zinc-poisoning, and bacterial preservation. Disinfectant tests have been carried out for the Stores Control Board.

FIELDS DIVISION REPORT OF P. W. SMALLFIELD, DIRECTOR Climatic conditions generally during the year ended 31st March, 1943, were in the main favourable from the agriculturist's point of view. The outstanding exceptions were in Southland, where one of the driest summers on record was experienced, and m Canterbury, where an excessive! rainfall has caused the harvest to be somewhat late. Arable Crops Wheat An intensive drive for an increased acreage of wheat for the season 1942-4o was made through the various District Councils of Primary Production in nrois The obiective was set at 300,000 acres, an increase of approximately 50,000 acres on'the area grown the previous season. While the objective was not fully attained, information on hand disclosed that approximately 283,000 acres were actually sown. Crops irive promise of vielding above average; the estimated yield per acre is 37 bushels, against an actual yield of 33-61 bushels the previous season. Basing emulations ori the above estimates, the total yield of wheat for the Dominion should approximate 10,500,000 bushels, compared with an actual yield last season of 8,611,244 bushels.

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