Relationship to growth performance of pneumonia and atrophic rhinitis lesions detected in pigs at slaughter among four seasons
Scheidt, A.B.; Mayrose, V.B.; Hill, M.A.; Clark, L.K.; Einstein, M.E.; Frantz, S.F.; Runnels, L.J.; Knox, K.E.
Journal of the American Veterinary Medical Association 200(10): 1492-1496
1992
ISSN/ISBN: 0003-1488 PMID: 1612984 Document Number: 396123
Pneumonia lesion scores and growth indicators did not correlate significantly during any of 4 seasonal investigations. Atrophic rhinitis lesion grades and growth indicators did not correlate significantly during the summer, autumn, and spring investigations. Correlation coefficients for average daily gain-total and grade for snout lesions (-0.37, P < 0.001) and for days to attain 104.5 kg and grades for snout lesions (0.40, P < 0.001) were significant during the winter investigation. Prevalence of lesions in lungs was highest during the winter and lowest during the autumn investigations. Prevalence of lesions in lungs was significantly (P < 0.05) higher between winter and spring vs summer and autumn investigations. Mean score for lesions in lungs was highest during the spring and lowest during the autumn investigations. Significant differences (P < 0.05) were noticed among all but the summer and autumn investigations. Prevalence of lesions in snouts was highest during the spring and lowest during the autumn investigations. Mean grades for lesions in snouts was highest during the spring and lowest during the autumn investigations. Significant differences (P < 0.05) were detected among the 4 seasonal investigations. Pigs from 1 herd were individually identified and weighed at birth and monthly thereafter up to and including slaughter. Lungs and snouts were retrieved at slaughter and examined later for gross lesions of pneumonia and atrophic rhinitis. Veterinary practitioners and researchers should realize the inherent limitations of slaughter examination data when trying to determine the benefit of vaccination, antimicrobial, or management programs implemented in herds.