The Slaughter of Broiler Chickens

SummarySome of the research results from which poultry slaughter methods were developed were wrong. Because of this, only about one third of broiler chickens are stunned in stunners as they are used today; the others are either killed outright or not stunned sufficiently. Although dead birds bleed slightly more slowly than stunned birds during the first 90 seconds after venesection, there is no difference between blood losses of the two groups after 180 seconds. Different amounts of blood left in the carcase make no detectable difference to the carcases, and the amount of blood left in the carcase does not affect the keeping quality. It is suggested that this lack of correlation between blood draining from the carcase and the quality of the carcase may be because the capillary bed of the muscles does not lose any blood—all the blood coming from the neck may be from viscera and large blood vessels. These findings indicate that all birds should be killed in the stunner, thus preventing the cruelty which is associated with present methods of slaughter. To do this, the voltage in the stunner should be set to a height which ensures that at least 120 mA pass through each bird. This can generally be achieved by 200 V—but the stunner dials often grossly overstate the voltage which actually passes through the stunner; the actual voltage and amperage in the working stunner (which may be less than half that in the idling stunner) should be measured by an electrician.