ENVIRONMENTAL-IMPACT OF PIG MEAT PRODUCTION

The aim of this paper is to examine the environmental effects of pig p roduction and possibilities at farm level to limit these effects. Acco rding to the 'EC Nitrate Directive' the application of animal manure s hould not exceed 170 kg N/ha. Supply of animal manure in the 12 Europe an member states exceeds 170 kg N per ha, approximately 13% of the num ber of holdings. The production of nitrogen from animal manure at memb er state level exceeds 170 kg N/ha in Belgium and The Netherlands. The performance and mineral excretion per sow and per fattening pig on Du tch farms in 1995 were estimated using data from 362 sow farms and 631 farms with growing-finishing pigs. Average annual P2O5 excretion per sow and per fattening pig amounted to 14.0 and 5.0 kg year(-1), respec tively. Average annual N-excretion per sow and per fattening pig amoun ted to 30.8 and 13.1 kg/year respectively. Observed differences betwee n farms in annual mineral excretion per animal are large. Farms with l ow annual mineral excretion have better productivity figures. The poss ibilities of reducing the mineral excretion are mainly dependent on th e onset of the situation. In many cases lowering the mineral content i n the feed alone will not be sufficient. There are possibilities for r educing the mineral excretion level but it takes time to implement the appropriate measures and they are not feasible for all farms. The emi ssion of ammonia from animals which is produced in the barn can only b e reduced by allowing new housing systems that meet specific environme ntal requirements. The emission of ammonia can be diminished by reduci ng the emitting surface, the slurry temperature, the air movement abov e 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. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.