Effects of Lactobacillus plantarum 15-1 and fructooligosaccharide on the response of broilers to pathogenic Escherichia coli O₇₈ challenge

Abstract

21One-day-old broilers were randomly allocated to 5 treatments: basal diet 22 challenged by saline (negative control, n-control); basal diet and challenged by E.coil 23 O 78 (positive control, p-control); supplementation with L. plantarum 15-1 at 1×10 8 24 CFU/kg challenged with E.coil O 78 (LP); supplementation with FOS at 5 g/kg 25 challenged with E.coil O 78 (FOS); supplementation with L. plantarum 15-1 and FOS 26 challenged with E.coil O 78 (LP+FOS). L. plantarum 15-1 or FOS had a lowered effect 27 (P＜0.05) on crypt depth on d 14 compared with two controls, and L. plantarum 15-1, 28 FOS and L. plantarum 15-1+FOS also reduced relative to p-control on d 21. L. 29 plantarum 15-1 reduced the level of diamine oxidase (DAO) at d 14 and 21 compared 30 with p-control (P＜0.05), the broilers with L. plantarum 15-1 and FOS increased the 31 concentration of IgA and IgG relative to two control, and decreased diamine oxidase 32 (DAO) compared with p-control (P＜ 0.05). L. plantarum 15-1 increased the 33 concentration of acetic acid and total short-chain fatty acid (SCFA) in comparison with 34 p-control at d 14 (P＜0.05), FOS improved the level of valeric acid and total SCFA 35 relative to p-control at d 21 (P<0.001), the broilers fed L. plantarum 15-1 and FOS 36 were increased the level of butyric acid at d 14 (P＜0.05). FOS enhanced bursal index 37 of broilers at d 21 (P＜0.05). L. plantarum 15-1 and FOS did no effect on the growth 38 performance. In conclusion, FOS can promote average daily gain, L. plantarum 15-1 39 and FOS can improve intestinal morphology, and increase the concentration of SCFA 40 in cecal contents in broilers challenged with E.coil O 78 . These results suggest that L. 41 plantarum 15-1 and FOS have effective mitigation to E. coil O 78 via lowing reducing 42 the intestinal injury and enhancing the immune responses. 43 Key words: animal models of infection, immunology, animal performance 44 45 Introduction 46 Escherichia coli (E. coli)-induced diarrhoea has become a global public health 47 problem, both in developed and developing countries. At present, the prevention and 48 treatment of the disease is mainly based on drugs and vaccines. In addition, dietary 49intervention has also become an important means [1]. E. coli can produce the 50 enterotoxin that causes colibacillosis, which brings untold damage for the poultry 51 production [2, 3]. E. coli whose serotypes are O1, O2, O78, O15 and O55 had been 52 found to be related to colibacillosis in chickens [4, 5], which may undermine immune 53 function to predispose host animals to the colonization of the pathogens, placing the 54 threat to health and food safety. Although antibiotic therapy is effective for 55 colibacillosis，there are increasing restriction and ban to limit the use of antibiotic to 56 poultry. Therefore, prebiotic and probiotic as candidates to replace antibiotics are 57 available, they are more secure to prevent and control colibacillosis, thus protecting 58 livestock species. Short-chain fatty acids produced by intestinal microbiota are o...

Immunomodulation of Avian Dendritic Cells under the Induction of Prebiotics

“…Short-chain fatty acids (SCFAs) are FOS metabolites produced by microbiota in chicken ceca, and some of them show anti-inflammatory properties that can explain the indirect influence of FOS on the gastrointestinal immune system [134]. Ding et al [135] evaluated butyrate, propionate, valerate, and acetate production in chickens supplemented with FOS. They found increased production of all evaluated SCFAs, but the highest production was of butyrate.…”