#02-124

Complete

Date Full Report Received

06/13/2003

Date Abstract Report Received

06/24/2009

Sub-therapeutic antibiotics attenuate bacterial growth and intestinal inflammation. These positive effects of anti-microbial agents result in increased feed efficiency and reduced time to market. The development of anti-microbial resistant bacteria pathogenic to humans has been linked to adding sub-therapeutic antimicrobials in pig dietary formulations. For instance, according to government surveys, most Salmonella isolates recovered from swine are antibiotic resistant. The results of this and previous studies from our laboratory demonstrate that, in similar action to antibiotics, conjugated linoleic acid (CLA) ameliorates intestinal inflammation in pigs. In contrast to sub-therapeutic antibiotics, CLA is not linked to the development of antibiotic-resistant bacteria. Hence, CLA may be a viable nutritional alternative to sub-therapeutic anti-microbial usage. This project has demonstrated that the anti-inflammatory effects of fish oil are very limited when compared to CLA. Furthermore, when both CLA and fish oil are added, the fish oil interferes with the anti-inflammatory effects of CLA. The economical benefits of dietary CLA-supplementation associated to G:F improvements during a bacterial infection average $6.72 per pig. These benefits can offset the initial cost of adding CLA in the diet (i.e., $5/pig). The next step of our line of research involves direct comparisons of the effects of CLA versus sub-therapeutic antibiotics in commercial hog operations.