Since 2001 France has seen its swine herd reduced, especially the sows, by approximately 0,6% and 1,6% per year, respectively. This decrease has been accompanied by a restructuring of swine farms. Farms with less than 20 pigs represent 58% of the farms as opposed to 68% in 2000, while the number of farms with more than 2000 pigs increased by 32%, and the herd by 36%, so that in 2009 these farms represented 46% of French swine livestock.
It is also worth noting that the geographical concentration of these farms has been aggravated; actually, 72% of the farms with more than 2000 animals are located in Brittany.
http://www.agreste.agriculture.gouv.fr/IMG/file/Gaf10p123-143.pdf