Duty cycle and high-frequency effects on welfare and meat quality of broilers chicken: compliance with European animal stunning regulation

Abstract

ABSTRACT: European market regulates that poultry electronarcosis stunning in abattoirs must be performed with a minimal required current (mA per animal) and correlative frequency (Hz), to promote animal welfare and meat quality. In this way, Brazilian abattoirs must adjust the stunning parameters so that they can meet the requirements of that market. This study evaluated the effect of stunning parameters using frequency and duty cycle variables. For this, nine treatments were performed, whose results showed that the analyzed frequencies (700, 1100, and 1500 Hz) had a higher incidence of indicators of animal welfare (AW). Thus, stunning had low efficiency in AW terms. However, the 25% and 40% duty cycles had the best stunning efficiency. There was no significant difference (P > 0.05) for pH 24 h, bruises, and drip loss. Color and pH 2 h were significantly affected (P < 0.05). The shear force was higher in birds subjected to higher frequencies and interaction between 1500 Hz and 15% and 25% duty cycles. Water-holding capacity was lower at 1100 Hz and in the 25% duty cycle interactions. The treatments affected the evaluated indicators, except for the 40% duty cycle, which had a positive influence. Therefore, the duty cycle applicability must be elucidated due to its direct influence on stunning efficiency.