The effect of methionine and aflatoxin on immune function in weanling pigs

• Published in: Journal of animal science Vol. 72; no. 3; p. 658
• Main Authors: Van Heugten, E, Spears, J.W, Coffey, M.T, Kegley, E.B, Qureshi, M.A
• Format: Journal Article
• Language: English
• Published: United States 01.03.1994
• Subjects: AFLATOXINAS; AFLATOXINE; Aflatoxins - pharmacology; Animals; Antibody Formation - drug effects; DIETA; Female; Immune System - drug effects; IMMUNITE CELLULAIRE; Immunity, Cellular - drug effects; Immunoglobulin G - biosynthesis; Immunoglobulin M - biosynthesis; IMMUNOGLOBULINE; INMUNIDAD CELULAR; INMUNOGLOBULINA; LECHON; Lymphocyte Activation; Male; METHIONINE; Methionine - pharmacology; METIONINA; PORCELET; Random Allocation; REGIME ALIMENTAIRE; REPONSE IMMUNITAIRE; RESPUESTA INMUNOLOGICA; SERUM SANGUIN; Skin Tests; SUERO SANGUINEO; Swine - immunology; Weaning
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/1994.723658x

To investigate the effect of aflatoxin (AF) and dietary methionine (MET) on immune responses of swine, a total of 288 pigs weaned at 21 d of age were allotted to 12 dietary treatments arranged in a 3 x 4 factorial arrangement in a randomized complete block design. Diets consisted of a corn-soybean meal diet (.95% lysine, 0.30% MET, and 0.32% cystine) containing either 0, 140, or 280 ppb of AF and supplemented with either 0, 0.15, 0.30, or 0.45% DL-MET. Immune response measurements were made after the pigs had received their diet for 3 wk. Antibody response to sheep red blood cells (SRBC) was measured 0, 7, and 14 d after i.m. injection of 2.5 mL of a 20% SRBC suspension. Total serum immunoglobulin (Ig) M and IgG were measured using an ELISA. In vivo cellular immunity was measured using a phytohemagglutinin (PHA) skin test. Skin thickness was measured 0, 6, 12, 24, and 36 h after s.c. injection of 0.1 mL of PHA (1.50 mg/mL). In vitro cellular immunity was measured using a lymphocyte blastogenesis assay. Antibody response to SRBC and serum IgM and IgG concentrations were not affected by dietary treatments. Skin thickness response at 6 h after injection was maximal when 0.45% MET was added to diets containing 280 ppb of AF, whereas the response was maximal at 0.30% supplemental MET for the 0 and 140 ppb of AF diets (AF X MET interaction, P 0.10). Skin thickness was reduced linearly (P 0.10) with increasing dietary AF at 12 and 24 h after PHA injection. In vitro lymphocyte blastogenesis was decreased ( P 0. 10) with increasing levels of MET. No differences in blastogenesis were observed due to AF. These results indicated that low levels of AF may depress certain aspects of cellular immunity Supplementation of MET did not improve immune function in pigs fed aflatoxin