The European Union already faces a significant blow to its credibility as at least a third of member countries will not be fully compliant with the January 2013 partial stalls ban.

And now some sources are suggesting that concrete slats with a slot width of over 18mm are commonplace in pig units across the continent and are still being installed, even though the ban on slot widths over 18mm is only nine months away.

If this proves to be the case, the cost to Europe's pig producers of fitting new flooring could be well over 3500m.

However, hopes are growing that the European Union will see fit to allow a manufacturing tolerance, as outlined in the European Standard for precast concrete products.

This will help producers with a slot width of 20mm between concrete slats. But those with a slot width of over 20mm will likely have to replace their concrete slats, at a total cost of around 345 a metre.

The reasoning behind the rule on slot widths is that widths over 18mm are considered by European Union legislators to increase the risk of injury to pigs.

However, feedback to date suggests pig producers dispute this view and consider the case for narrower slot widths is not proven.

The 18mm rule was introduced in European welfare legislation in 2003, but with a period of grace for existing pig housing until January 2013.

But it now appears that not only did the new rule go unnoticed by European pig-keepers with existing housing, but it may also not have been spotted by producers who have put up new pig housing between 2003 and the current date.

In Britain, the NPA is working with Defra to find out whether or not a significant number of producers have concrete slats with slot widths over 18mm, and whether a tolerance, to allow for manufacturing variability should be considered.

BPEX is investigating whether, if necessary, it will be possible to use some form of insert to reduce existing slot widths to 18mm, although even if a solution is found, it will come at a cost.

The European Union's problem is that it already faces a shortage of pigmeat next year as a result of its January 2013 partial stalls ban. If it places any added financial burden on European pig producers, the results could be dire.