Nitrogen losses and hygiene for finishing pigs

Last changed: 06 December 2023

Organic growing finishing pigs with access to outdoor concrete areas

Project manager: Jos Botermans, Rural Buildings and Animal Husbandry, SLU
Project group: Knut-Håkan Jeppsson and Anne-Charlotte Olsson, Rural Buildings and Animal Husbandry, SLU.

In order to be able to create a sustainable organic pig production in all aspects it is necessary to find practical solutions for the problems with ammonia emissions and hygiene observed on the outdoor concrete areas. This is particularly important since organic production systems with outdoor concrete areas are most commonly used. During eight months of the year, the pigs have access to outdoor concrete areas without access to pasture areas. In year 2003, 70% of the piglet production and 60 % of the finishing pigs were kept in such systems.

Results from a previous organic pig project (part of SLU’s EcoPig project) showed that the total nitrogen losses were much higher (by about a factor of 4) in organic pig production as compared to conventional pig production. A main reason was the larger dirty area, especially, the outside concrete area in organic production.

The objectives of the present project are to explore possible ways for improving the hygiene and reducing the ammonia emission and nitrogen losses (N) from the outdoor concrete areas in organic growing-finishing pig production. The planned measures are to cover parts of the concrete area (= the animal activity area) with different types of rooting material.

The hypothesis is that animal activity will be increased in the area with rooting material while at the same time dunging and urinating will be concentrated to a more limited part (= the dunging area) of the outdoor area. This will decrease the total area with manure and decrease ammonia emission. In addition, the rooting material is also expected to have the ability to bind ammonia.

  1. A total of four different treatments will be applied and compared:
    control (no rooting material)
  2. wood shavings
  3. peat
  4. peat daily enriched with green feed pellets, sugar beet pellets, etc.
  • Evaluation of the different treatments will be made by means of observations of:  growth and feed utilization, 
    animal health, 
  • behaviour and 
  • hygiene and by 
  • measuring the ammonia emission from the outside concrete area.