The Effects of Different Waveforms and Frequency Values in Pre-slaughter Stunning by Electricity on Some Welfare Parameters and Carcass Defects

Objective: In this study, the effects of electric current application including different wave types and frequency values on welfare parameters and carcass defects to render broilers unconscious before slaughter were examined. Material and Methods: In study, a total of 180 forty three-day-old broilers were divided into 9 treatment groups with 20 chickens (10♀-10♂) each. Treatment groups consist of a control group without electricity and eight groups stunned by using the electric current. Broilers were stunned in water bath with the electric currents, sine wave alternating current (AC) and pulsed direct current (pDC) of 120 mA and frequencies of 50, 200, 400, and 1000 Hz. To reveal the condition of chickens after the electric treatment, electrocardiogram (ECG) was recorded. Besides, the reflexes of eye, comb, foot, and the responses of breathing, wing flapping, shaking, cardiac fibrillation in chickens were also determined. Amount of blood loss in chickens during bleeding was measured. Also, carcass defects assessed. Results: The applied electrical current for stunning affected significantly the reflexes of eye, comb, and foot, the behavior of wing flapping and respiratory of broilers. The electrical stunning was generally increased carcass defects in broilers. Carcass defects caused by electric application occurred in the form of hemorrhagic spots in the middle part of wings and thighs in broilers (P<0.05). Conclusion: The results of research showed that chickens were better effectively stunned at the frequencies of 50 and 200 Hz, AC.