Come on Clint. That's not strickly true. They use anesthetic first then a clamp, for 30/40 seconds. Some use bands, similar to human hemorrhoid banding treatment.
In the article below it says we have made progress it doesn't say its banned here -
Some countries, like the
UK and Ireland, have made progress toward that goal by slaughtering pigs before puberty, which reduces pork yields.
Right now, surgical castration of pigs without anesthetic is the norm in many countries, including the US. Its defenders, including the dominant US pork producer
Smithfield Foods, argue that the procedure is necessary to avoid “boar taint,” an unpleasant odor and taste produced by the hormone androstenone and the digestive compound skatole.
But castration without anesthetic is, obviously, incredibly painful. A literature review from the
American Veterinary Medical Association in 2013 documents extensive evidence that piglets experience pain during castration, from their high levels of stress hormones like cortisol, their squealing, and their trembling and lying alone for days following the procedure.
Policymakers in the European Union have been trying to abandon surgical castration for years; a
2010 declaration by an EU panel called for its abandonment in all EU member states by 2018, a goal that was very clearly not reached. Some countries, like the
UK and Ireland, have made progress toward that goal by slaughtering pigs before puberty, which reduces pork yields.
Full article -
https://www.vox.com/future-perfect/2019/11/22/20974479/pig-castration-pain-humane-pork