I'm going to mostly let the video above speak for itself. It does a pretty good job of again showing the inherently cruel conditions in factory farms, as well as giving a graphic example of why apologists for raising animals in such conditions would like to see photography of farms banned.
Be warned that the leading image of the video is about the most pleasant image. Be prepared for seeing piglets having their tails and testicles chopped off without anesthesia, lots of bloody pigs in gestation crates, and more.
Background to the video: The Humane Society of the United States has just released the video resulting from an undercover investigation of Seaboard Foods and Prestige Farms, both located in Goodwell, Oklahoma and the third and fifth largest pork producers in the US. Seaboard is a supplier to Walmart.
Because the abuse documented at the Seaboard facility is in stark contrast to statements on the company's website about animal care, The HSUS filed legal complaints against the company with the SEC and FTC urging the agencies to require that Seaboard stop misleading its shareholders and the public.
The HSUS notes that Seaboard and Prestage are lagging behind their competitors in the pork industry when it comes to animal welfare. Cargill has transitioned 50 percent of its sow operations from gestation crates to group housing, and Smithfield Foods has pledged to be gestation crate-free by 2017.
If you live in the US, unless you know for a confirmed fact that the meat you eat was produced differently than in the conditions shown the video above, you can safely assume the animals were raised in undoubtedly inhumane conditions.