The effect of Escherichia coli ŽP strain with a conjugation-based colicin E7 delivery on growth performance, hematological, biochemical, and histological parameters, gut microbiota, and nonspecific immunity of broilers

• Published in: Canadian journal of microbiology Vol. 68; no. 11; pp. 687 - 702
• Main Authors: Orlova, E.G, Maslennikova, I.L, Pospelova, J.S, Erjave, M. Starcic, Loginova, N.P, Troinich, Y.N, Kuznetsova, M.V
• Format: Journal Article
• Language: English
• Published: Ottawa NRC Research Press 01.11.2022; Canadian Science Publishing NRC Research Press
• Subjects: Bacillus; Bacteria; Biochemistry; Broilers (Poultry); Chromosomes; Clostridium; Colibacillosis; Colicin E7; Conjugation; Deoxyribonuclease; Digestive system; E coli; Erythrocytes; Escherichia coli; Gastrointestinal tract; Genetic aspects; Genetic modification; Genetically modified organisms; Health aspects; Hematology; Hemoglobin; Immunity; Immunoglobulin Y; Inflammation; Intestinal microflora; Intestine; Leukocytes; Lysozyme; Microbiota; Microbiota (Symbiotic organisms); Oral administration; Parameters; Peyer's patches; Phagocytes; Physiological aspects; Plaques; Probiotics; Prophylaxis; Reactive oxygen species; Russia
• ISSN: 0008-4166; 1480-3275
• DOI: 10.1139/cjm-2022-0044

The Escherichia coli ZP strain (ZP) was constructed based on the known probiotic E. coli strain Nissle 1917. It was genetically modified to carry the colicin E7 synthesis gene encoding DNase on a conjugative plasmid and the colicin E7 immunity gene in the chromosome. The aim of this study was to evaluate the effects of the daily ZP per oral administration (5 x [10.sup.8] or 5 x [10.sup.10] CFU per bird) on the growth performance, hematological, biochemical, histological parameters, gut microbiota, and nonspecific immunity of the 4-24 days old broilers. The ZP administration increased the abundance of genera Bacillus, Butyrivibrio, and Clostridium and did not influence the weight gain of 4-16 days old broilers. The biochemical parameters were within normal ranges for poultry in experimental and control groups. The ZP administration had no effect on the erythrocyte numbers, hemoglobin and immunoglobulin Y concentrations, but significantly increased the serum lysozyme concentration, leukocyte numbers, and reactive oxygen species production by phagocytes compared with the control group. It did not cause inflammatory changes in intestinal mucosa, Peyer's patches, and spleen. Thus, the ZP had no detrimental effects on broiler health and could be an efficient probiotic for the broiler colibacillosis prophylaxis.