Date Full Report Received05/01/2014
Date Abstract Report Received05/01/2014
InvestigationInstitution: Iowa State University
Primary Investigator: Alejandro Ramirez, Scott Hurd
Funded ByNational Pork Board
The objectives of this study were three-fold: (i) develop a national estimate for peelout prevalence in swine carcasses, (ii) determine if common respiratory pig pathogens are associated with peelouts (specifically Streptococcus suis, Pasteurella multocida, Bordetella bronchiseptica, Actinobacillus suis, Actinobacillus pleuropneumoniae, and Haemophilus parasuis) and (iii) determine if peelouts are associated with Salmonella contamination. Six abattoirs were selected from different geographical areas of the United States, and samples were evaluated at two time periods. At each abattoir visit, 50 lesioned (peel-out present) and 50 non-lesioned (peel-out absent) carcasses were sampled. Lung samples and pleural swabs were taken from each carcass. A standard bacteriological identification and culture was performed. A national prevalence estimate was obtained. Peelout prevalence ranged from 2.64% to 28.39%, with an average of 9.78% (95% CI 5.33% to 14.23%). Contamination rates for respiratory pathogens varied greatly, and there was no consistent pattern among lesioned/non-lesioned carcasses. The prevalence of respiratory contamination for lesioned and non-lesioned carcasses was as follows: Streptococcus suis, 5.45% to 50%, 2.04% to 56.76%, Pasteurella multocida, 0% to 33.33%, 0% to 42%, and Bordetella bronchiseptica 0% to 6.12%, 0% to 2.22%. Salmonella prevalence ranged from 0% to 23.53% in lesioned carcasses, and 0% to 16% in non-lesioned carcasses. While there appears to be little association between respiratory bacterial contamination and peelouts, these pathogens still play a significant role in swine health. While a significant association was not found between peelouts and Salmonella contamination in all abattoirs, the effect that peelouts can have on animal health and carcass contamination, and therefore public health, should not be ruled out. This is especially true in abattoirs that have a high Salmonella prevalence.