Dietary supplementation with Atractylodes Macrophala Koidz polysaccharides ameliorate metabolic status and improve immune function in early-weaned pigs

Abstract

The effects of Atractylodes Macrophala Koidz polysaccharides on metabolic status and immune function in early-weaned pigs were determined. 25 [Duroc×(Landrace×Yorkshire)] crossbred pigs, weaned at the age of 21days (body weight 5.30±0.25kg), were randomly allocated to 5 dietary treatments, with 5 pigs in each treatment. The dietary treatments were: the basal diet (BD)-fed group, the pure Atractylodes Macrocephala Koidz polysaccharides (PAMKPS)-fed group (BD+0.3% PAMKPS), the crude polysaccharides mixture (CPSM)-fed group (BD+0.6% CPSM), the crude Atractylodes Macrocephala Koidz polysaccharides (CAMKPS)-fed group (BD+0.6% CAMKPS) and the antibiotics (AN)-fed group (BD+0.015% chlortetracycline+0.005% flavomycin). Diarrhea scores were recorded daily, and the average daily gain (ADG), average daily feed intake (ADFI) and feed/gain ratio (F/G) were measured weekly. Blood samples were obtained for the measurement of serum metabolites and immune function related parameters, contents from ileum, cecum and colon were collected for enumeration of coliform and lactobacillus counts, and tissue samples were collected for the determination of cAMP contents and mRNA abundances of cytokines. Diets supplemented with the PAMKPS, CPSM and CAMKPS increased ADG (P<0.05) and decreased F/G (P<0.05) compared with the BD. The diarrhea incidence in pigs of the PAMKPS-fed group was lower (P<0.05) than that in both the AN and BD-fed group, and that in the CPSM and AN-fed group was lower (P<0.05) than in the CAMPKS and BD-fed group, respectively. The counts of coliform in ileum contents of the PAMKPS-fed group, that in cecum contents of the PAMKPS, CPSM, CAMKPS and AN-fed group, and that in colon contents of the PAMKPS and AN-fed group were lower (P<0.05) than that in the BD-fed group; the counts of lactobacillus in ileum contents of the PAMKPS-fed group, that in cecum contents of the PAMKPS, CPSM and CAMKPS-fed group, and that in colon contents of the PAMKPS, CPSM, CAMKPS and AN-fed group were higher (P<0.05) than that in the BD-fed group, respectively. Diet supplemented with the PAMKPS ameliorated (P<0.05) the metabolic status of blood urea nitrogen, alanine amiotransterase and aspartate amiotransterase compared with the BD, and diets supplemented with the CAMKPS and CPSM improved (P<0.05) the glucose metabolic process compared with the AN-added diet. Diet supplemented with the PAMKPS increased (P<0.05) the serum concentrations of immunoglobin (Ig) G, IgM, tumor necrosis factor (TNF)-α, interferon (IFN)-γ and cyclic adenosine monophosphate (cAMP), and spleen and liver contents of the cAMP compared with the BD. Diets supplemented with the PAMKPS and CPSM increased (P<0.05) the peripheral blood lymphocyte transformation rates and mRNA abundances of the interleukin-6, TNF-α, IFN-γ, and the nuclear factor of activated T cells transcription factor (NF-AT) in spleen compared with the AN-added and BD diets. We concluded that the PAMKPS, CAMKPS and CPSM could ameliorate the metabolic status and regulate immune function to beneficially improve the growth performance in pigs, and such function was better than that of antibiotics.