USE OF PAIRED CARCASS HALVES IN TESTING OF ANTIBACTERIAL TREATMENTS

Authors: Cason Jr, John; Young, Louis; Berrang, Mark

Submitted to: European Symposium on Quality of Poultry Meat
Publication Type: Proceedings
Publication Acceptance Date: 5/15/2003
Publication Date: 9/23/2003
Citation: Cason Jr, J.A., Young, L.L., Berrang, M.E. 2003. Use of paired carcass halves in testing of antibacterial treatments. European Symposium on Quality of Poultry Meat. September 23-26, 2003. St. Brieuc, France. 1:243-246.

Interpretive Summary: Two methods of testing experimental agents for controlling germs on poultry meat were compared. In one method, a chicken is exposed to the experimental agent, and then germ counts on the meat are compared to similar counts on another chicken which was not exposed to the test agent. In the second method, half of one chicken is exposed to the experimental agent, and germ counts on that half are compared to germ counts on the other half which was not exposed to the experimental agent. Results of these studies indicate that the second method is the more sensitive of the two

Technical Abstract: Using counts of chicken carcass bacteria from a previous experiment, 100 data sets were generated to test the efficiency of a completely randomized design (using counts from whole carcasses) versus a random block design (using paired left and right carcass halves) for testing effects of treatments on numbers of bacteria. Mean reductions in counts to obtain a significant difference between control and treatment groups for aerobic bacteria, coliforms, and E. coli were 0.44, 0.51, and 0.63 for the randomized design and 0.25, 0.26, and 0.35 for the random block design, respectively, with significant differences between the two designs for all three types of bacteria. Correlations between counts on opposite halves of carcasses make random block designs more sensitive for testing.