Effects of cyadox and olaquindox on intestinal mucosal immunity and on fecal shedding of Escherichia coli in piglets

• Published in: Journal of animal science 2006-09, Vol.84 (9), p.2367-2373
• Main Authors: Ding, M.X, Wang, Y.L, Zhu, H.L, Yuan, Z.H
• Format: Article
• Language: English
• Subjects: Animal productions; Animals; antimicrobial agents; Bacteria; Biological and medical sciences; cyadox; Dietary supplements; disease transmission; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - isolation & purification; Escherichia coli - physiology; Escherichia infections; feces; Feces - microbiology; Fundamental and applied biological sciences. Psychology; heterocyclic nitrogen compounds; Hogs; Immunity (Disease); Immunity, Mucosal - drug effects; Immunoglobulins; Immunologic Factors - pharmacology; intestinal mucosa; Intestinal Mucosa - drug effects; Intestinal Mucosa - immunology; liveweight gain; lymphocytes; Male; medicated feeds; mucosal immunity; olaquindox; pathogen shedding; Physical growth; piglets; Quinoxalines - pharmacology; Swine - immunology; swine feeding; Terrestrial animal productions; Vertebrates; Weaning
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/jas.2005-564

A 2 x 3 factorial arrangement of treatments was used to determine the effects of olaquindox and cyadox on the intestinal mucosal immune response and on fecal shedding of Escherichia coli in Landrace x Large White barrows that had been orally given 10¹⁰ cfu of E. coli (O₁₃₉:K₈₈). Factors included 1) E. coli inoculation or no inoculation, and 2) no antimicrobial, 100 mg of olaquindox/kg, and 100 mg of cyadox/kg in the basal diet, respectively. The effects of cyadox and olaquindox were assessed in terms of fecal shedding of E. coli, the number of intraepithelial lymphocytes (IEL), immunoglobulin A-positive cells (APC) in the intestinal lamina propria, and ADG. There was no difference in the fecal shedding of total E. coli or the inoculated E. coli between olaquindox-supplemented pigs and cyadox-supplemented pigs during the experiment. However, fecal shedding of the inoculated E. coli in olaquindox- or cyadox-supplemented pigs was less (P < 0.05) than that in nonsupplemented pigs. Escherichia coli inoculation increased IEL and APC in the jejunum and ileum, but olaquindox or cyadox decreased IEL and APC (P < 0.05). Jejunal APC in cyadox-supplemented pigs was less (P < 0.05) than that in olaquindox-supplemented pigs. Escherichia coli inoculation reduced (P < 0.05) ADG, whereas the supplementations improved ADG (P < 0.01) during the experiment. Average daily gain in cyadox-supplemented pigs was greater (P < 0.05) than that in olaquindox-supplemented pigs. The data indicated that olaquindox and cyadox reduced the number of intestinal E. coli and suppressed E. coli-induced immune activation, which might be responsible for the enhanced growth that was observed.