Incidence and economics of tuberculosis in swine slaughtered from 1976 to 1988.

The Swine Tuberculosis Regulations, revised in 1972, stipulated that all swine carcasses with mycobacterial lesions in more than 2 primary sites should be passed for cooking (PFC). Economic loss from a condemned carcass is 100%, whereas loss from a PFC carcass is 66%. Increased condemned and PFC swine carcass rates in 1972, 1973, and 1974, and the economic losses from them were attributed to changes in the regulations. An industrial organization estimated increased economic losses from swine tuberculosis, but detected decreased rates of condemned and PFC swine carcasses in 1975 and 1986. The federal meat inspection data for 1976 to 1988 indicated that the yearly condemned carcass rate remained < 8.0/100,000 swine slaughtered, whereas the PFC carcass rate decreased by 74.1%, from 52.4 to 13.6/100,000 swine slaughtered. The incidence (condemned + PFC) per 100,000 swine slaughtered decreased by 67.7%, from 58.03 in 1976 to 18.72 in 1988. The Agricultural Statistics indicated that a yearly loss from tuberculosis of $2.3 million in 1976 decreased by 73% to $0.97 million in 1988. A yearly loss of $41,580/$100 million of animal value decreased by 70% to $12,880/$100 million in 1988. The decreased incidence of swine tuberculosis and the economic losses with this disease indicate that the swine industry in the United States was not adversely affected by the change in the Swine Tuberculosis Regulations.