Environmental impact of pig meat production

Abstract

The aim of this paper is to examine the environmental effects of pig production and possibilities at farm level to limit these effects. According to the ‘EC Nitrate Directive’ the application of animal manure should not exceed 170 kg N/ha. Supply of animal manure in the 12 European member states exceeds 170 kg N per ha, approximately 13% of the number of holdings. The production of nitrogen from animal manure at member state level exceeds 170 kg N/ha in Belgium and The Netherlands. The performance and mineral excretion per sow and per fattening pig on Dutch farms in 1995 were estimated using data from 362 sow farms and 631 farms with growing-finishing pigs. Average annual P 2O 5 excretion per sow and per fattening pig amounted to 14.0 and 5.0 kg year −1, respectively. Average annual N-excretion per sow and per fattening pig amounted to 30.8 and 13.1 kg/ year respectively. Observed differences between farms in annual mineral excretion per animal are large. Farms with low annual mineral excretion have better productivity figures. The possibilities of reducing the mineral excretion are mainly dependent on the onset of the situation. In many cases lowering the mineral content in the feed alone will not be sufficient. There are possibilities for reducing the mineral excretion level but it takes time to implement the appropriate measures and they are not feasible for all farms. The emission of ammonia from animals which is produced in the barn can only be reduced by allowing new housing systems that meet specific environmental requirements. The emission of ammonia can be diminished by reducing the emitting surface, the slurry temperature, the air movement above the emission surface, the N contents and the pH of the slurry. Over the last few years, low emission housing systems for each pig category have been developed.