|ROH, SANGGUN - Tohoku University
|Carroll, Jeffery - Jeff Carroll
|KIM, SUNG - North Carolina State University
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/30/2014
Publication Date: 5/20/2015
Citation: Roh, S.G., Carroll, J.A., Kim, S.W. 2015. Effects of fermented soybean meal on innate immune responses of nursery pigs acutely challenged with lipopolysaccharide. Livestock Science. 86(5):508-516.
Interpretive Summary: Scientists within the Livestock Issues Research Unit participated in a collaborative study with scientists from North Carolina State University and industry to determine the innate immune response of pigs acutely challenged with a bacterial toxin as affected by dietary protein sources either from fermented soybean meal or spray dried plasma protein compared to soybean meal. The primary focus was to evaluate changes in gene expression associated with immunological markers. Collectively, most of the genes regulated in the current study by feeding dietary fermented soybean meal are potentially related to the reduction of inflammatory response and anti-oxidative activity in pigs after exposure to a bacterial challenge. It is anticipated that this response may benefit the growth of nursery pigs during the postweaning period as observed in previous studies from this group. Potential reduction in inflammatory responses may be one of the reasons for the decreased serum cortisol release that has been observed in pigs feed fermented soybean meal after exposure to a bacterial endotoxin compared with pigs fed control diets containing soybean meal. Future studies should focus on determination of functional responses at the level of the actual cytokines and enzymes related to affected genes to further support the results found in this study. Further studies are also needed to investigate whether or not the alterations in gene expression and decrease cortisol secretion associated with feeding fermented soybean meal will be beneficial with regard to decreasing the severity and duration associated with an immunological challenge in the weaned pig.
Technical Abstract: This experiment was conducted to determine if replacing soybean meal (SBM) with fermented soybean meal (FSBM) would reduce the innate immune response of nursery pigs to an immune challenge with lipopolysaccharide (LPS) and to examine the changes of gene expression profiles associated with this response using oligonucleotide microarray analysis. Forty-eight pigs (21.8 ± 0.7 days of age) were weaned, housed individually, and fed 3 diets (n = 16/dietary group) for 15 days: CON (a control diet without FSBM and spray dried plasma protein; SDPP), PP7 (a diet with 7% SDPP), and FS10 (a diet with 10% FSBM). Pigs were fitted with a jugular vein catheter on day 14, and received a systemic challenge of LPS (25 micrograms/kilogram of body weight) on day 15. Blood samples were collected for 5 hour at 30-minute intervals to measure serum concentration of cortisol. Expressions of gene transcripts in total RNA from leukocytes were compared between CON and FS10 using an oligonucleotide microarray at 210 minutes after LPS injection. The average dailey gain and gain:feed did not differ among treatments during the 15-day period. Average serum cortisol concentration of FS10 was lower (P < 0.05) than CON but did not differ from PP7 after the LPS challenge. The expression levels of 17 transcripts including cytosolic glutathione peroxidase, hydroxyacylglutathione hydrolase, and glutathione S-transferase A4-4 were increased (P < 0.05) in leukocytes of pigs fed with 10% FSBM. However, mRNA levels of 23 genes including adiponectin, neonatal Fc receptor and TNF ligand superfamily member 5 (CD 40 ligand), were decreased (P < 0.05) in FS10. Results from this study suggest that FSBM fed pigs can modulate expression of genes related to inflammatory response and anti-oxidant activity which can be a potential reason for reduced serum cortisol even though determination of functional responses at the level of actual cytokines and enzymes related to affected genes would further warrant the results found in this study.