Reply #6: here is a quote

[rumpel]

from the same article undergroundpanther links to

The condemned livestock carcasses treated with these toxic chemicals can then become meat and bone meal for the pet food industry. Worse yet, since rendering facilities are not government-controlled, any animal carcasses can be rendered, including those of cats and dogs. Eckhouse quotes Eileen Layne of the California Veterinary Medical Association: "When you read pet-food labels and it says meat or bone meal, that's what it is -- cooked and converted animals, including some dogs and cats."

Some of these dead pets -- those who were euthanized by veterinarians -- already have sodium pentobarbital in their bodies before being treated with the denaturing substances. In veterinary offices most cats and dogs are put to sleep with this chemical. According to Eckhouse, veterinarians at the University of Minnesota warned that the sodium pentobarbital used to put pets to sleep "survived rendering without undergoing degradation," but they concluded that the residue amount would be too small to cause problems if the carcasses of euthanized pets were mixed with other raw materials during a day's production run. No mention was made of the cumulative effects on a cat or dog from ingesting this small amount daily for years. Thus far we have come across the denaturing chemicals and the sodium pentobarbital, and I have only just begun.

In the finished rendered product, a fat stabilizer is introduced to prevent rancidity. The common chemicals used are BHA (butylated hydroxyanisole) and BHT (butylated hydroxytolulene), both known to cause liver and kidney dysfunction. Some European countries prohibit the use and importation of these preservatives. Another fat stabilizer often used is Ethoxyquin, suspected of being a cancer-causing agent. Propylene glycol, first cousin to ethylene glycol (antifreeze), is found in many semimoist dog foods. It causes the destruction of red blood cells.

http://www.belfield.com/article3.html