Experimental trial of the effect of fumonisin B1 and the PRRS virus in swine

Abstract

Fumonisin B1 (FB1) belongs to a group of mycotoxins produced by fungi of the genus Fusarium. In swine farms, the presence of the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) causes significant economic losses in Mexican swine industry. In this experiment, the effect of the presence of FB1 and PRRSV was evaluated in five groups of 5 pigs; Group A: Negative control; Group B: Inoculated with 12 ppm of FB1 starting from day 0; Group C: Inoculated with PRRSV on day 8; Group D: Inoculated with PRRSV and 12 ppm of FB1 starting from day 0, respectively and Group E: Inoculated with 12 ppm of FB1 starting from day 0 and inoculated with PRRSV on day 8. Daily Weight Gain (DWG) and pathologic and histopathologic changes in the lung, liver and kidney were evaluated and the presence or absence of PRRSV was determined by the RT-PCR test in the groups treated. A negative slope effect was observed in weight gain in groups D and E (-0.103 and -0.37, respectively) indicating weight loss with the presence of PRRSV and FB1 Regarding the percentage of macroscopic lung lesions, it was found that group B had reddish consolidation, 1.4%; group C showed diffuse consolidation, 9.42%; group D had diffuse consolidation, 5.41% and reddish consolidation, 1.63% and group E had diffuse consolidation, 5.91% and reddish consolidation, 3.50%. The histopatologic findings in the lungs were: thickened alveolar septa with mononuclear infiltrate, with vascular changes and clean alveoli characteristic of interstitial pneumonia. In group D in which the pathogens were administered on day 0, moderate diffuse interstitial pneumonia was observed. Group E showed severe interstitial lung lesion. Polyploidy and binuclear cells were observed in the liver, suggesting mycotoxicosis in groups B, D and E. Another organ that showed alterations was the kmdney in groups B, D, E and a mononuclear cell infiltrate was found in only one piglet in group C. Proliferative glomerulonephritis was observed in association with these damaged parts of nephrons as well as size-reduced, shrinked and atrophied glomeruli. On the other hand, the results obtained to prove the presence of PRRSV by the RT-PCR technique were negative for group A and group B and were positive for groups C, D and E, which were inoculated with PRRSV according to the experimental design. Based on the results obtained in this study, it could be observed that PRRSV and FB1 have an additive effect in swine. It was also observed that group E had a greater lung damage histologically. © Medwell Journals, 2010.