Hi
To be honest I have no idea if the slapmark was visible on the carcase as we had the pigs butchered by the abattoir so never saw the complete side. I haven't had any comments back from the abattoir to say there was a problem, though the abattoir is fairly small and our pigs were not in amongst a whole load of other pigs so identification problems didn't seem to be much of an issue.
Tish