...I've heard about Mexican immigrant poultry workers fucking chicken carcasses on the processing line, but I'm not going to list it as porn I don't get.
Never seen the Mexican angle. At the AVN Awards in 2006(?), they had little video interludes where Randy Spears was calling a D/s phone sex line, and each whore got him to do some thing dumber and dumber each time. One was to fuck a whole chicken (processed, of course). It was actually pretty funny.