Constant current electronarcosis of market poultry
This study was conducted to optimize the parameters involved in the electronarcosis of market chicken and turkeys. A prototype constant current stunner designed at the Department of Electrical Engineering of Virginia Polytechnic Institute and State University was used. Broilers were electrically stunned with 8, 29 and 50 mA per bird. Turkeys were electrically stunned with 10, 30 and 50 mA per bird. Three weight classes, controlled by age, were used as treatment levels. Broiler males were grown for 36, 43 and 50 days while females were grown for 37, 44 and 51 days. Turkey hens were grown for 84, 98 and 112 days, while toms were grown for 112, 126 and 140 days. Pre-stun levels of 3, 5 and 8 hours of feed and water withdrawal were used for each weight class and sex. The effect of sex, weight and feed and water withdrawal on stunning efficiency, recovery time, blood splatter, bone breakage, color and pH of the breast meat was determined. The experimental unit for each specie, sex, weight and feed withdrawal class used was a "pen" comprised of 10 birds. A total of 130 birds, by gender and specie are used for each repetition. Two repetitions of all experiments were accomplished. A third repetition was done in turkeys, but this time a cooping time of three hours prior to slaughter was added. All data was statistically analyzed with ANOVA and a Box-Behnken response surface design was used to optimize the current for the different experimental variables. Results indicated a significant (p < 0.0001) gender difference in resistance, recovery time and prevalence of defects in both broilers and turkeys. Optimization of the stunning process parameters was not achieved due to inability of the model to express logistic regression equations at the levels used in this study.