Summary

Transport is a stressor of poultry but when this is compounded with heat stress; the challenges to the birds can result in dehydration, increased mortality and decreased carcass yield and meat quality. Under Australian summer conditions transport heat stress, can be severe. While much effort has been given to improving production efficiency on farm, some of this improvement is lost during processing. Previous RIRDC funded work in ducks has given a 3-4% increase in processed carcass weight when the birds were supplied with electrolytes for 32h before pick-up.
The current proposal will investigate the use of electrolyte and betaine supplementation of broilers for a short period prior to transport, as a strategy to help reduce bird dehydration and minimise the effects on carcass yield and meat quality. The project will also determine the effect that transport crate density has on these measures.
Two studies are proposed, one during the summer and one during winter, using the facilities of the Poultry research Unit, The University of Sydney, which has a strong record of providing research for the chicken meat industry.
The expected outcomes are, improved bird welfare by reducing the physiological stress load imposed on broilers during transport and lirage. To limit the degree of dehydration the birds suffer during transport and a reduction in carcass weight loss. To limit the adverse effects of transport on meat quality and to identify the most appropriate crate density during transport.
The treatment effects on faecal and litter moisture content will also be determined.

Program

Chicken Meat

Research Organisation

The University of Sydney

Objective Summary

An over reaching objective is to address management and physiology issues that constrain production and productivity in the chicken meat industry and/or which result in adverse animal welfare outcomes.
The research strategy will address some husbandry and physiological issues that constrain carcass yield efficiency and result in adverse animal welfare during transport and processing.

The industry acknowledges that bird welfare is a legitimate community concern that warrants research. The transportation process has been considered the most stressful environmental challenge experienced by broilers (Mitchell and Kettlewell, 1998). This is especially the case where heat stress is also experienced during transport, and this is common under Australian conditions. Heat stress during transport is the main cause of mortalities during the processing process. While there can be good environmental control in the grow-out sheds, this control is lacking during transport.

While transport stress is not directly a food safety issue, it does result in birds dehydration, changes in energy metabolism, increased muscle pH, and these can result in reduced meat quality. Direct competition of chicken meat with other meats, can’t simply depend on price; the product quality needs to be at least comparable. Improved meat quality would have an influence on consumer acceptance and continued support for the industry and its sustainability.

Mitchell, M.H. and Kettewell, P.J. (1998) Poultry Science, 77, 1803-1811.