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item Wells, James - Jim
item Yen, Jong Tseng

Submitted to: Conference on Gastrointestinal Function
Publication Type: Abstract Only
Publication Acceptance Date: 2/16/2005
Publication Date: 4/13/2005
Citation: Wells, J., Yen, J. 2005. The effects of larch extract on performance and fecal flora in nursery pigs. Proceedings of the 2005 Conference on Gastrointestinal Function. p. 18.

Interpretive Summary:

Technical Abstract: The swine industry is under pressure to minimize synthetic antimicrobial growth promoters in diets. Larch extract is predominantly a polymer of arabinogalactan containing up to 20% taxifolin, which exhibits antibacterial properties. To determine the potential benefit of larch extract in young swine diets, 192 nursery piglets were sorted by weaning weight into one of four treatment diets: 1) no growth promoters (negative control, NC); 2) Mecadox + copper sulfate (positive control, PC); 3) 0.1% larch extract (LE); or 4) 0.2% larch extract and were fed for a 4-week period. The PC group consumed significantly more feed over the 4-week period relative to the other three diet groups (200 g vs 183 g per animal, P < 0.05), but did not gain significantly more weight (110 g vs 105 g per animal, P > 0.1). Gain to feed was significantly lower at week 2 for the PC group relative to all treatments, but 0.1% LE was significantly higher (0.64 g/g) than the PC or NC groups (0.58 and 0.61 g/g, respectively). No effect on gain to feed was observed from week 2 to week 4. At week 4, fecal Lactobacillus spp., coliforms, and Escherichia coli were similar (approximately 8.56, 4.99, and 4.87 log10 CFUs per g feces, respectively) for NC and both LE groups. However, for the PC diet group, the Lactobacillus spp. CFUs (7.59 log10) were nearly 1 log lower, and the coliform and Escherichia coli CFUs (6.02 and 6.02 log10, respectively) were more than 1 log greater than the other three treatments. Fecal shedding of pathogens (Salmonella spp. and Campylobacter spp.) was lowest for the LE groups (15%) and highest for the NC group (25%). From this study, larch extract may be a beneficial feed additive to nursery swine at less than 0.2% of diet.