The temperate climate of almost all of New Zealand suits European types of cattle. Most of the dairy farms are in lowland areas of the North Island, where naturally fertile or improved soils make for good grass growth. There is no good evidence to suggest that dairy cattle of the European breeds suffer from the direct effects of climate in these areas, but climate does play a large part in determining their productivity through its effects on the feed supply. Severe or prolonged winters, or droughts in summer, are the most usual causes of lowered yields of dairy produce.

Most dairy produce comes from specialised dairy farms where the main food for the cattle is pasture, in the main grazed directly, though some feed is stored as hay or silage in times of good growth against times of shortage. Only limited irrigation of grassland is carried out. Fodder crops are commonly used to provide extra food in the driest part of the summer and sometimes for winter feeding, but very little grain or other concentrate is given. New Zealand dairy farming is seasonal because it relies on pasture which grows best in the spring and early summer and least in the winter. Most of the cows calve in late July and August and are not lactating in the winter.

Herds supplying milk for towns and cities differ a little from this pattern. Because these herds must produce milk all the year round, some cows are calved in summer and others in autumn and winter; but even these farms rely mainly on pasture, and the peak of milk production is usually in the spring when pasture growth is most rapid.

The amount of labour used on New Zealand dairy farms per 100 cows is low compared with that of other countries. Because cows are grazed on pastures, little labour is needed for feeding stock, and labour-saving machinery is much used. In 1918–19 about half the cows were milked by machines; by 1941 the proportion was 86 per cent, even higher in intensive dairying areas.

The reasons for the predominance of the Jersey are not certain, but two may be suggested. Studies of the performances of dairy cows in different climates have shown that Jerseys can usually stand a little more heat than Friesians, which may give them an advantage in the wamer parts of New Zealand. Also, the Jersey produces less non-fatty milk solids per pound of butterfat than other breeds. This would be expected to make it a more efficient producer of butterfat, an advantage in a country where payment for dairy produce has usually been based on the number of pounds of butterfat contained in it.

Characteristic butterfat and non-fatty-solids content of the milks of the cows of the four main breeds in New Zealand are shown as follows:

The cattle brought to New Zealand by the early European settlers seem to have included many Shorthorns, originating in England, but some came through Australia. They were probably of mixed strains, some more suited to milk production, others to beef, and others intermediate. The developing trade in dairy produce demanded specialised dairy breeds; and the numbers of Ayrshires, Friesians, and Jerseys increased. Most of the change in the dairy cattle which occurred was brought about by using purebred bulls of the dairy breeds as sires in commercial herds. Their progeny were reared and used as replacements until, at the present time, many of the non-purebred or “grade” cattle differ very little from those of one or other of the pure breeds.

Of the total of 3,133,000 dairy cattle in New Zealand, 175,000 or 5½ per cent are registered pedigree stock, and the remainder are unregistered purebred and crossbred stock. Since 1950 there have been marked increases in the number of Friesians and Ayrshires, a marked decrease in the number of milking shorthorns and only a slight increase in the total number of Jerseys.

Other dairy breeds, such as the Guernsey, Red Dane, and Brown Swiss, which are important in other parts of the world, have very few, if any representatives in New Zealand.

New Zealand had no cattle prior to the European settlement. In the early nineteenth century a few European cattle were brought to the first settlements, usually coastal. The cows increased and their milk supplied local demands. But distance prohibited overseas trade in dairy produce until refrigeration made it possible. The first refrigerated cargo left New Zealand in 1882 and the volume of dairy produce exported from New Zealand has increased ever since. Centrifugal separators in dairy factories (1885) were another important innovation. These give an efficient recovery of butterfat from milk. The introduction of smaller separators on farms allows those some distance from factories to be used for dairying. In areas with poor roads it was easier to transport cream than the more bulky milk.

The new dairy industry grew rapidly. Large areas of new land were cleared for farming; the use of fertilisers, particularly phosphates, improved strains of pasture plants, and better methods of pasture management made possible the feeding of larger numbers of dairy cows. The rate of increase in cow numbers varied, but the total continued to increase until the Second World War when, chiefly because of labour shortages, it fell a little, only to rise again more rapidly immediately after the war. This expansion ended about 1950 and, during the decade 1950–60, dairy cow numbers varied between about 1,900,000 and the peak of about 2,000,000.

The increased dairy production was not due alone to increases in the number of cows. The average productivity of cows, too, has increased steadily rather than spectacularly, and has continued after the numbers of cows were stabilised. It has almost certainly been due largely to improved feeding, milking, and disease control.

The butter produced in New Zealand is of a salted type and, because the cows are fed almost entirely on grass, it has a high carotene content which makes it yellower than the butter from countries where cows are fed indoors for much of the year. The cheese exported is a cheddar, although a little of other kinds is made for local sale. Milk powders include those made from whole milk or from separated milk and buttermilk, by-products of buttermaking. Lactose is made from whey, a by product of cheesemaking. At one time skim milk, buttermilk, and whey were almost entirely fed to pigs; but in recent years more has been dried, and the pig industry, which depended on dairy by products, has been declining.

*Estimated.

The New Zealand national dairy herd of between 1,900,000 and 2,000,000 cows is unsurpassed for its contribution to world trade in dairy produce, though it ranks only twelfth compared with the herds of other countries. Of the 1,224 million gallons of milk produced in 1963–64, 88.4 per cent was used for making butter, cheese, milk powders, and casein, and most of this was exported. The part played by the dairy industry in world trade is shown by the figures in the following table:

Research into dairy manufacturing is done by the Dairy Research Institute—a body controlled by a board with representatives from the industry, the Government, Massey College, and the Dairy Factory Managers' Association. The Institute studies problems of manufacture and packaging, the development of new products, and improvements of machinery and methods. The Institute is housed at Massey University of Manawatu.

J.V.W.

There are two dairy associations, the National Dairy Association and the South Island Dairy Association. These were developed to do work similar to that later done by the Dairy Board, with more attention to some of the industry's technical problems, especially manufacture, packaging, and transport, also the training of staff. The National Dairy Association did, however, interest itself generally in marketing and in specific matters, such as the arranging of freight contracts and the allocation of shipping space.

When, however, the Dairy Board was formed. the dairy associations became trading-type concerns specialising in the supply of machinery and other dairy-factory needs. They later became, as they are at present, limited liability companies with dairy companies the shareholders. They have undoubtedly saved the industry much money by buying supplies wholesale and, although they are not greatly in the public eye, they have an important place in the organisation of the dairy industry.

Apart from its marketing activities, the New Zealand Dairy Production and Marketing Board has many important technical functions, the most important being its herd-improvement work. The Board employs about 12 consulting officers, who advise farmers on production. It carries out all testing of dairy cows and does much research into statistics which serve to guide farmers in the selection of suitable breeding stock, including a continuing survey of the production records of the progeny of selected bulls. The Board runs on a business basis the Artificial Breeding Service at Newtead, near Ruakura, a service taken over from the Department of Agriculture, which had set it up. The Board administers the Bobby Calf Marketing Regulations, which organise the sale of bobby calves through a pooling system, to ensure that farmers receive full returns for their calves.

In New Zealand pig meat is a by-product of the dairy industry, for almost all pigs are fattened mainly on skimmed milk. The New Zealand Pig Producers' Council, responsible for the development and welfare of the pig industry, works therefore under the New Zealand Dairy Production and Marketing Board Act. The Council also runs a National Pig Breeding Centre to improve the quality of breeding stock.