SHANGHAI: A second industrial chemical that regulators have found in contaminated pet food in the United States may also have been intentionally added to animal feed by producers seeking larger profits, according to interviews with chemical industry officials here. Three Chinese chemical makers said that animal feed producers often purchase, or seek to purchase, the chemical, cyanuric acid, from their factories to blend into animal feed. The chemical producers said it was common knowledge that for years cyanuric acid had been used in animal and fish feed. In the United States, cyanuric acid is often used as a disinfectant for...