Immunological Response of Pigs By Lymphocyte Proliferation By the Supplementation of Beta-Glucans

With increasing pressure to reduce of in-feed antibiotics, many swine producers have looked for alternatives to maintain pig health immediately after weaning. The objective of the study was to evaluate the immunological response to graded levels of beta-glucans (CitriStim, ADM, Quincy, IL) in comparison to in-feed antibiotics in diets fed to weaned pigs. A total of 96 weaned pigs (7.74 ± 0.31 kg, 21 d of age) were used in a 14-d study to evaluate the effects of beta-glucans on growth performance and immune responses in weaned pigs. Allotment was done randomly to 1 of 4 dietary treatments (6 pens/treatment) according to intial BW: negative control (NEG) containing no antibiotics or beta-glucans, the NEG with feed grade antibiotics (POS), the NEG with the inclusion rate 20 lbs/ton of beta-glucans (BG₁) and the NEG with the inclusion rate of 60 lbs/ton of beta-glucans (BG₂). Experimental diet was a standard nursery Phase II diet (d 1-14 post wean). Assesment of immune response was based on lymphocyte proliferation in response to mitogens Concanavalin A (ConA) and Phytohaemagglutinin (PHA-P) (d 7, 14). No significant difference was detected between treatments for ADG (0.25, 0.23 0.27, 0.25 kg/d, pooled SEM 0.06, respectively, in NEG, POS, BG₁, and BG₂), ADFI (0.34, 0.29 0.37, 0.31kg/d, pooled SEM 0.10, respectively) and feed to gain ration (0.57, 0.51 0.55, 0.49 kg, pooled SEM 0.05, respectively). No significant response difference in lymphocyte proliferation amongst all treatments occured at both evaluated time points ConA (P-value ≥ 0.672 d 7, P-value ≥ 0.770 d 14) and PHA-P (P-value ≥ 0.586 d 7, P-value ≥ 0.692 d 14). In conclusion, no significant impact was found by using various rates of beta-glucans within the feed on the immunological response measured by lymphocyte proliferation.