Pigs and poultry have this in common in their place on the farm, they can both exist as separate and distinct units, more or less divorced from the general economy of the farm as a whole. Except in special circumstances, pigs cannot exist solely on farm grown foods and must rely on purchased foods, which in most cases have to be imported into this country. Egg production can, however, be maintained at a reasonably high level on home produced feeding stuffs. This is well illustrated by what has happened in Northern Ireland during the war years. During the seven years prior to the war, there was a remarkable increase in pig population, and in 1939 the number of pigs was approximately two and a half times what it was in 1932. This expansion was due to more or less stable prices brought about by the operation of the Northern Ireland Pigs Marketing Board, and was based on imported cereal foods, maize from the Argentine and wheat offals from Australia. A poultry population of some ten million also consumed large quantities of imported feeding stuffs. In the autumn of 1939, the rapid decrease in supplies of feeding stuffs operated immediately against the pigs, and by June 1940 there was a reduction of 41 per cent, in the pigs under two months old and an overall reduction in pigs of 24 per cent, as compared with June 1939. This reduction continued until 1944, but there are signs of some improvement this year with promises of better supplies of feeding stuffs.

The problems of pig breeding in this country can be treated under two headings : those affecting (1) the commercial producer and (2) the pedigree breeder. It is only by proper organization and co-operation between the two that the best results can be obtained for the pig industry as a whole. As it should be the object of the pedigree breeder to produce animals suitable for commercial production, the commercial breeding of pigs will be dealt with first and the special problems of the pedigree breeder later.