If the effect of amino acids is calculated in isolation, one pig (a 2019 pig in breeding terms) fed on 2019 feed will excrete 31 percentage points less nitrogen than if the same pig were to be fed typical feed from the end of the 1980s. The corresponding figure for ammonia evaporation is 36 percentage points lower for a pig on 2019 feed compared to the same pig and feed from the end of the 1980s. 

• Breeding for higher daily gain and an improved feed conversion ratio as well as breeding for more live born pigs per litter has also contributed to the positive development. The switch from solid manure and liquid manure to special housing systems has also reduced ammonia loss.
• Breeding for more live born pigs per litter contributes to sustainable development with less resource consumption per produced piglet.  

With regard to phosphorus, the widespread use of the enzyme phytase has contributed to a decrease in excreted phosphorus per pig. The reduced use of artificial fertiliser and the increased use of nitrogen in livestock manure have resulted in the fact that since 1990, agriculture has almost halved the leaching of nitrogen into the aquatic environment.