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The development of the dairy industry was closely linked with the development of better crops and animals and with a host of technological changes, such as improved transportation, refrigeration and advancements in milk processing. For example, in earlier times, one of the biggest problems was keeping milk fresh so that it would not spoil. Milk used to be kept cool by putting a container in the shade or in cold spring water near the farm or home. Today it is automatically cooled as soon as it is removed from the cow; it is carried long distances in large refrigerated tanks and then processed and packaged for placement in refrigerated showcases in grocery stores. The production of milk in many countries is now a large, scientifically based, highly mechanized industry.