The use of halothane and succinylcholine to identify broilers prone to developing pale, soft, exudative meat

Abstract

Within the last several years, the poultry industry has seen a dramatic increase in the occurrence of pale, soft, and exudative (PSE) meat. This problem is known to be associated with a rapid decline in postmortem (PM) muscle pH, which results in inferior protein functionality similar to that found in PSE pork. Many factors such as seasonal changes have been known to influence the occurrence of PSE meat in poultry and swine. Halothane and succinylcholine have been used within the pork industry to identify animals susceptible to stress and prone to developing PSE meat. The mechanism for the triggering of the PSE gene in poultry has not been fully understood. Therefore, a study was conducted to determine the effectiveness of screening broilers with halothane to identify those prone to developing PSE meat. Succinylcholine was used before slaughter to serve as a triggering agent for the PSE condition. At 4 wk of age, broilers from 4 commercial strains (n = 1,000) were subjected to 3% halothane gas and classified as either halothane positive (HAL+) or negative (HAL-) based on muscle rigidity within the legs. Although halothane sensitivity varied slightly among the strains, approximately 14% of the birds overall were classified as HAL+. All HAL- birds (n = 163) and an equal number of HAL-birds (n = 163) in each strain were grown to market age (7 wk) and were commercially processed. At the time of processing, half of the HAL+ and HAL- birds were injected intravenously with succinylcholine and were slaughtered at 0.25 h postinjection. Pectoralis muscle samples were collected at 0.25, 2, 5, and 24 h PM for the evaluation of rigor development (muscle pH) and meat quality (L* value, moisture, drip loss, and cook loss). Halothane sensitivity had no effect on rigor development, muscle color, or water-holding capacity in the 4 broiler strains. Although birds exhibited reactions to the halothane gas, the halothane sensitivity, along with the use of succinylcholine, was not able to identify birds prone to developing PSE meat.