BUTTER FLAVOURS

Dominion, Volume 30, Issue 255, 24 July 1937, Page 10 (Supplement)

BUTTER FLAVOURS

Effect of Grazing Cows on Different Pastures RESEARCH AT RUAKURA The problem of feed flavour in cream, resulting from the grazing of dairy stock on certain types of pasture, especially in the Auckland province, is being investigated by the Department of Agriculture at the Ruakura State Farm, and although the investigations have already yielded valuable results, the researches are being continued in the hope that further information for the guidance of farmers may be obtained, states a bulletin just issued. The Waikato investigations were instigated by Mr. A. M. Sterling, late manger of the Morrinsville Co-opera-tive Dairy Company, and were taken up by the Dairy Research Committee and the Dairy and Fields Divisions of the Department of Agriculture, working in collaboration. Research work was instituted at Massey Agricultural College, where individual cows were stall-fed on different types of pasture, aud at Morrinsville, in co-operation with the dairy company’s suppliers. Up to the present, although the cause of feed flavour is still unknown, the conditions which bring about strong feed flavour have been confirmed and reconfirmed. These conditions are: (1) The time of the year; (2) the weather; and (3) the proportion of grasses to clovers in the herbage which the cows eat.

It has been found that the strongest feed flavour in cream occurs during the period of most rapid active growth In the spring, and that the strongest flavours come from the more clovery pastures, while the mildest flavours emanate, from the least or most grassy pastures. Furthermore, annual clovers such as suckling clover or subterranean clover cause stronger flavour than does white clover. It follows then that feed flavour is reducible by increasing the gross growth and reducing the clover growth of pastures. This does not mean a reduction in number of plants, but simply a reduction In growth. Guiding Principles. Although the feed flavour investigation has not yet progressed sufficiently to show exactly how this can best be done, the following guiding principles have been established:— (1) Never hard graze a pasture for long periods, particularly in the early winter and early spring. Hard grazing weakens the ryegrass and encourages the clover. On the other hand, very lenient grazing in the winter and early spring strengthens the ryegrgss by increasing the root s’ystems and weakens the clover by smother. Therefore a system of long spells between rapid but lenient grazings should be adopted. (2) Topdress with superphosphate and lime in the autumn. Topdressing is effective only if there is sufficient white clover in the sward to make use of it. and only when the increased growth passes through live stock. Phosphate manuring starts a cycle of clover, phosphates., more clover, more stock, more consolidation of light lanrj by tramping, more stock nitrogen, more grass, more phosphates, still more clover, still more stock, still more hoof cultivation, still more stock nitrogen, still more grass. While the carrying capacity and production are being built up in this way, the pasture is likely to remain clover dominant for some years, and feed flavour will persist, but although the phosphate-elover-stock-mtrogen method, plus controlled grazing, is slow, it is also sure, ant! from other points of view the most practical at the present time. For the purpose of having some pastures dominant in ryegrass in the spring, artificial nitrogen may be used on areas intended for spring grazing. Several fields may be topdressed in May with ammoniated super, 3cwt. to the acre. These fields should then be shut up for early spring use. and only very lightly grazed in the winter.

8. Feed good bay in periods of strong feed flavour. 4. In periods of strong feed flavour graze the most grassy pastures during the day. and the most eloverv nt night Keep the cows off clovery pastures "for about four hours prior to the afternoon milking. In general feed flavour is much stronger in night’s cream than in mornings cream. This w mainly due to the fact thnt cows ration themselves at night when they are adequately fed That is to say. they usually graze up to abrntt midnight ’but thereafter, until morning milkin", they may be down. 5. Cool the cream properly and keep it as free ns possible from bacteria. It cannot, be too, strongly stressed that rhe basic principle is not to over-redtice the ' Th nt clover, which is essential for the well-being of the ryegrass, but to increase the growth of the ryegrass. Farmers Co-operate. At Morrinsville the department is co--1 operating with a number of farmers and ha s extensively investigated the possibilities of using artificial nitrogenous manures for altering the grass to clover ratio of pastures. The work has now heen transferred to Ruakura because it has reached, a stage where the refined research required cannot be done co-operatively. I'he i chief aim at present is to find out the I fundamental principles of grazing mani ngement of pastures. Observations at i Morrinsville indicate that a greater ; change in the grass-clover ratio can be made by controlled grazing than by the use of expensive artificial fertilisers. For the purpose of continuing the investigation a 15-aere field at Ruakura. where the soil is representative of the flat land of the IVaina ■ and Waikato counties, and the pastures typical of the districts which give strong feed flavour, has been subdivided into a small dairv farm of twelve fields of equal size. A two-bail milking shed is being erected, and about fifteen cows will be used for trrazing. The twelve fields are not intended to carry the fifteen cows all the time, and other grazing will be available if required. The idea is not to run the area as a self-contained dairy farm, but to graze the fields according to a definite pre-determined programme. Some differential top dressing is being carried out. The cream from the herd will be critically graded for feed flavour from each grazing, and in addition to the Ruakura work regular contact will be made with the experiments still being carried out at Morrinsville. In addition to the investigations with the special herd of fifteen cows, it is hoped to divide the main herd at Rnakurn into two equal-sized herds. It is suggested that both herds should be adequately fed up till midday, but that after middav one of the herds will be run on a hare paddock. The object is to discover whether a herd fed adequately up to middav maintains its yield of milk when taken off pasture until the afternoon milking, for the spell from grazing definitely reduces feed flavour. Whether such a spell also reduces the quantity of milk produced is a point yet uof settled.