Friday, 11 February 2011
Food withdrawal prior to slaughter helps to reduce cross-contamination with salmonella and other organisms at the abattoir. If a pig has a full gut and the bowel opens during or just after slaughter, the faecal matter will go into the polisher and the water tank. The next pig going through will then get leftovers spread on its surface.
If the faecal matter was infected with salmonella it means that, instead of just one pig with salmonella on the carcase, it can spread to other potentially clean carcases. Staff and equipment handling the contaminated carcase could also contribute its spread.
BUT it is important to get the length of the pre-slaughter fasting period right. When a pig is fasted it will mobilize body tissues to provide energy for maintaining the vital functions of the body.
Fasting pigs for 24 hours is too long as it can result in a loss of 3.8% of their initial liveweight and 2.1% of carcase weight, compared with a fasting period of only four hours. The optimal fasting period is 8–12 hours.
For more information, please click here and download 2TS Action for Productivity no. 7: Factors affecting killing out percent.