There are various possibilities for traditional forms of housing for fattening pigs which can satisfy the maximum legally permissible threshold value for ammonia by 2013 by means of relatively simple combined measures (feed/nutrition, simple housing measures, management measures). These were some of the conclusions of research carried out by Wageningen UR Livestock Research, funded by the Dutch Product Board for Livestock and Meat (Productschap Vee en Vlees, PVV).
In 2013, all farms must have low ammonia emissions. For farms with fattening pigs, this means a maximum ammonia emission level of 1.4 kg per annum per animal space. Wageningen UR Livestock Research has made an inventory of the possible ways of reducing ammonia emissions on pig farms through combinations of relatively simple measures such as feed/nutrition in combination with inexpensive modifications to the housing and management measures. In this way, the ammonia emissions can be reduced without the necessity for major interventions or expensive modifications to the housing. This is particularly important for pig farms that do not opt to increase their scale and therefore do not invest in large new housing units, but instead opt to continue their operations at the current scale with the existing animal housing.
A few promising combination measures are: the reduction of the protein content of the feed, the addition of benzoic acid to feed (VevoVitall®), the application of an odour trap in the case of manure pits being constructed underneath, the replacement of concrete grids with metal triangular grids, the acidification of the manure, the installation of a system of floating balls in the manure pit acting as a cover, leaving sections empty, and earlier delivery. A simple model has been set up to calculate the effect of combinations of measures on ammonia emissions. By combining measures, ammonia emission reduction can be achieved varying between around 30 and 70%. Pig farmers will need to weigh up for themselves which combined or individual measures are most suitable for their own farms.
Most combinations of simple measures have still not been included in the statutory procedures for ammonia and livestock farming (RAV). It would cost a great deal of time to continuously measure all the promising combinations of measures. For this reason, the report includes the recommendation to continuously measure the emission reduction in a number of promising combinations. The data can then be used to check whether the model provides good predictions. In addition, the model can be used to derive emission factors for other combinations of measures.
The report also offers tools for the monitoring and enforcement of the measures mentioned.
Report available for download free of charge
Report 366 ‘Reductie van ammoniakemissie op vleesvarkensbedrijven via gecombineerde maatregelen’ (Reduction of ammonia emission from houses for growing-finishing pigs by combined measures) by A.J.A. Aarnink et al. can be downloaded free of charge from http://edepot.wur.nl/155192
For further information about this study, please contact project leader Hilko Ellen, e-mail: hilko.ellen@wur.nl, tel.: +31 (0)320-293504