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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Poultry Microbiological Safety and Processing Research Unit » Research » Publications at this Location » Publication #311483

Title: Impact of extended stun duration and voltage on the recovery of consciousness in broilers

item HARRIS, CAITLIN - University Of Georgia
item Bourassa, Dianna
item WILSON, KIMBERLY - University Of Georgia
item Buhr, Richard - Jeff

Submitted to: International Poultry Scientific Forum
Publication Type: Abstract Only
Publication Acceptance Date: 11/20/2014
Publication Date: 1/26/2015
Citation: Harris, C., Bourassa, D.V., Wilson, K., Buhr, R.J. 2015. Impact of extended stun duration and voltage on the recovery of consciousness in broilers [abstract]. International Poultry Scientific Forum. 94:(E-Suppl.1)M48. p.15, 2015.

Interpretive Summary:

Technical Abstract: Typical electrical stun duration for broilers in the United States is from 5 to 15 s (depending on voltage), but would be considerably longer if and when the kill-line stopped. The welfare and conscious/unconscious status of broilers within the stunner cabinet is a concern while the line is stopped and when the line restarts. Therefore, the effect of stun duration (60, 90, or 120 s) at two voltages (15 or 20 V pulse DC at 550 Hz) was investigated in a pilot processing facility. Two d prior broilers were selected by weight between 2.9 to 3.1 Kg and were subjected to a 12 h feed withdrawal. Individual broilers were hung on the shackle line, feet wet to maximize ground contact, and line was started. The standard stun duration in this pilot plant stunner is 10 s, so at 5 s when the broilers were at the middle of the stunner cabinet (brine depth 2.5 cm) the line was stopped for an additional 50, 80, or 110 s. The line was then restarted and the broilers stunned for the remaining 5 s. Upon exiting the stunner cabinet the broilers were immediately removed from the shackle line and placed on the floor on their side to enable observation of ventilation and/or mandibular movements. Within 120 s, if the broiler did not exhibit any skeletal muscle movements and the comb became pale, they were recorded as not recovered. Recovered broilers initiated movement within 15 s and were able to maintain vertical posture at 120 s when placed on their feet. Broilers were individually stunned in sequential batches of 5 broilers at the same voltage setting and duration before changing parameters. All broilers stunned at 15 V for 60 s recovered (5/5 broilers). However, broilers stunned at 15 V for 90 s did not recover (0/5 broilers) and no broilers stunned at 15 V for 120 s recovered (0/5 broilers). Broilers stunned at 20 V for 60 s only 3/6 broilers recovered, unexpectedly those broilers stunned at 20 V for 90 s 2/10 recovered, and no broilers were tested at 20 v for 120 s. For stun durations of 60, 90, or 120 s for either 15 or 20 V, recovery of consciousness did not appear to be related to a lower stunning amperage (21 to 49 mA) compared to those that did not recover (23 to 44 mA).