A recent letter written by members of the US-based Equine Welfare Alliance (EWA) in the online publication HarnessLink states that horses from the US that are sold for slaughter in Mexico and Canada are transported with complete records of all the medications each horse received.

As the slaughtered horse meat is currently imported into Europe, the letter raises concern that these administered substances include toxic wormer drugs such as phenylbutazone (PBZ), which is a known carcinogen as well as fertility drugs that can cause miscarriages in women, both of which are banned from animals slaughtered for food.

The letter concludes with an appeal to the US Congress to pass existing bills that would outlaw the killing of horses for meat altogether, saying that equines should be preserved as companions rather than slaughtered.
We join in saddened shock, Equine Welfare Alliance members, along with our thanks to you and HarnessLink for bringing this matter to public attention.

Let us quickly turn to the wholesome and humane meat-free diet for our health and peaceful co-existence with the majestic horse and all animal co-inhabitants.

http://www.harnesslink.com/www/Article.cgi?ID=77195
http://www.horsetalk.co.nz/news/2009/12/051.shtml