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drawn, but the indications _ are that chronic cases do not respond to the treatment. One or two acute cases have shown rapid recovery, but it is impossible without many more trials to say whether he recovery was spontaneous or due to phage action. Phage treatment of streptococcal mastitis has not yet been tried. Cheese-manufacture. During the past season experiments in the manufacture of two types of cheese with reduced fat content have been made :— (1) Cheese with a fat content of ,30 per cent, in the dry matter. This may possibly be required for supply to liberated areas in Europe. Its manufacture would make possible the export as a valuable human food of much milk protein at present being converted into pig-meat: 6 (2) Cheese with a fat content of 52 per cent, in the dry matter. Although years ago the manufacture of standardized cheese was tried commercially and abandoned, there is the possibility that at some time in the future it may be made in New Zealand in order to render economic the use of high-testing milk. The present experiments were designed to determine whether there were any technical difficulties in the production of high-quality standardized cheese. It was found that the removal of fat from cheese-milk leads to the production of a curd which loses its moisture much more readily in the cheesemaking process than a normal curd Unless variations from the normal procedure are adopted, therefore, the result is a dry and harsh cheese. Ihe variations necessary are all in the direction of reducing cooking temperature and the period of cooking. I his helps to retain the requisite amount of moisture in the cheese so that it will mature normally and develop the usual smooth plastic " body." ni. Ij Wa f f ° Und tllat ttlore was 110 difficulty, given these variations, in making a high-quality Cheddar cheese containing 52 per cent, of fat in the dry matter. When once the correct procedure had been determined it was possible to make a standardized cheese indistinguishable from a normal full-cream cheese. _ There was greater difficulty in the manufacture of 30 per cent, fat cheese. Even with extreme variations on manufacturing procedure the cheese was always rather harsh when examined soon alter manufacture and it suffered from marked mechanical openness. However, after a maturing period of three to four months the body mellowed to a remarkable degree and it ultimately proved quite edible cheese, although always easily distinguishable from the full-cream product. meet of Feeding of Cows on Characteristics of Cheese-milk,—ln nutrition experiments two groups of cows paired as equally as possible from a production point of view had been fed on pasture, silage nay, and roots, and one group had in addition received a ration of concentrates. On three different occasions the milks from the two groups were made separately into cheese and their differences in behaviour were observed. It was found that after a prolonged dry-weather period milk from cows on normal pasture gave the usual soft curd which was difficult to " cook." Milk from the other group receiving an extra ration of concentrates gave much better, _ although not quite normal, curd. At periods when pasture was m plentiful supply there was no difference between the curds produced from the two milk-supplies : ey both cooked normally. It was observed, also, that differences between the two curds in a drought period were much more marked than the slight differences in chemical composition between the milk would have led one to expect. Curd characteristics in the cheese-vat seem to be a very sensitive indicator of milk variations due to feed variation and/or environment of the cow Cleaning of Milking-machines.-The shortage of electric power for use in electric water-heaters on dairy-farms has attention towards methods for cleaning milking-machines using the minimum of hot water. During the past season trials have been made of a method used for the last ten years m America a,nd Canada which consists in immersing teat-cups and milk-tubes in a 0-5 per cent, solution of caustic soda between milkings. The soaking treatment in cold caustic soda takes the place of the rinsing treatment with hot caustic solution and boiling water, the present standard practice m New Zealand. So far as the teat-cups and rubber milk-tubes are concerned, the cold-soak treatment gives good results, but in New Zealand there is also an overhead metal milk-pipe and releaser to be cleaned ; American machines are almost all of the bucket type. In our trials with two milking-machines a treatment of the overhead pipe with warm caustic-soda solution and rinse o hypochlorite solution was tried. So far as bacteriological quality of the milk was concerned the results were promising, but there was an undesirable formation of scale in the metal pipe due to the hypochlorite solution which would ultimately cause trouble. Further trials with different overhead milk-pipes are projected. Dairy Cow Nutrition.-The 1944-45 season is the fourth in which the production and composition of milk from cows receiving pasture and normal farm supplement—i.e., silage, hay, roots, and green fodder crops-has been contrasted with that from cows which have been fed meal in addition to the above foods. This experiment is designed to determine whether animals fed according to good New Zealand dairy practice produce at a level comparable with that of animals offered an adequate plane of nutrition throughout their entire lactation. It is designed also to determine whether it is possible period U g alone, to maintain the normal composition of milk throughout a hot dry summer The results in the seasons (including the current one) when conditions have been very favourable for pasture growth are m marked contrast to those obtained in the 1943-44 season—one in which extremely dry summer and autumn conditions were experienced. Throughout the work in seasons when a plentiful supply of leafy pasture has been available, no outstanding difference has been observed m the production level and in the composition of the milk from the two groups of animals RTZi v I a f bn ™% tot dry summer (1943-44) which occurred during the four years of trial', the S.N.r. content of the milk from both groups declined to abnormally low levels. This last point is of special interest, as m previous work at the Institute it has been shown that a low plane of nutrition may depress the S.N.F. percentage of milk. Apparently the availability of sufficient nutrients is not the only factor influencing the decline in the S.N.F. content of milk of cows at pasture m a hot dry summer period. However, it is interesting to note that, although the S.N.F.

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