beta-1-3-Glucan Effect on Sow Antibody Production and Passive Immunization of the Piglet

Beta-1, 3-glucans (beta-glucan) are complex, glucose homopolymers known to modulate immune capabilities when administered intravenously, intramuscularly or orally. This study investigated the beta-glucan effect on sow antibody production and subsequent passive immunization of neonatal piglets. Crossbred sows (n = 24; parity3-9) were mated and 5 weeks prior to farrowing assigned to one of four treatments (n = 2 sows/treatment within each farrowing groups; n = 8 total sows/treatment). Treatments included: Corn-soy fed Control group, beta-glucan (5 mg kg(-1) body weight), App (Actinobacillus pleuropneumoniae; Pneu-Pac (TM); Schering-Plough) vaccination (5 and 2 weeks pre-farrowing) and beta-glucan (5 mg kg(-1) body weight) + App vaccination (5 and 2 weeks pre-farrowing). All sows were maintained on treatments from 5 weeks pre-farrowing to 2 weeks post-farrowing. Piglet performance was not affected (p>0.05) by treatment as indicated by similar birth and weaning weights between treatment groups. Independent of treatment, IgA, IgG and IgM in colostrum were elevated and declined rapidly as the age at weaning approached. The concentration and rate of decline in IgA, IgG and IgM in colostrum, milk and piglet serum were not affected (p>0.05) by treatment. Vaccination against App (treatments 3 and 4) resulted in an increase (p<0.05) in IgG and IgA specific for App serotypes 1, 5 and 7 in colostrum and milk and a corresponding increase (p<0.05) in serum in piglets at 4 d of age. However, beta-glucan did not enhance specific App antibodies in piglet serum.