EFFECT OF A Lactobacillus FERMENTATION PRODUCT ON GROWTH, IMMUNE RESPONSE AND FECAL ENZYME ACTIVITY IN WEANED PIGS

Abstract

Forty-eight crossbred piglets were weaned between 4 and 5 wk of age and assigned according to sex and body weight to a complete block design with a 2 × 3 factorial arrangement of treatments, to determine the effect of a Lactobacillus fermentation product (LFP) on growth, feed intake, diarrhea, serum IgG and IgA levels and activity of two fecal enzymes, β-glucuronidase and β-glucosidase. Two levels of LFP, none and 0.1% on an as-fed basis, and three vaccination treatments with transmissible gastroenteritis virus (TGE), none (NV), intramuscular (IMV) and oral (OV) were used. Vaccination treatments began at 7 wk of age. The addition of LFP improved body weight gain (P ≤ 0.04) and increased feed intake (P ≤ 0.04). At weaning, serum IgG and IgA levels were not significantly different between treatments. Piglets fed LFP had significantly higher serum IgG levels than piglets fed the control diet on the day of vaccination (P ≤ 0.05) and at the end of the feeding period (P ≤ 0.02); no effect was observed on serum IgA level. Vaccination with TGE, either OV or IMV, did not affect IgG or IgA titers in serum. Fecal enzymes, β-glucuronidase activity and β-glucosidase activity were not affected by diets. Results demonstrated that LFP stimulated growth, increased feed intake and slightly increased serum concentration of IgG. Mechanisms by which LFP exerts these effects on piglets are discussed. Key words: Lactobacillus, fermentation product, immune response, growth, swine