Vet World Vol.17 March Article - 13
Research Article
Veterinary World, 17(3): 612-619
https://doi.org/10.14202/vetworld.2024.612-619
Anatomical, pathological, and histological features of experimental respiratory infection of birds by biofilm-forming bacteria Staphylococcus aureus
1 Department of Veterinary Medicine, Russian Biotechnological University (BIOTECH University), 125080, Moscow, Russia.
2 Department of Veterinary Medicine, Agrarian Technological Institute, Peoples' Friendship University of Russia (RUDN University), 117198 Moscow, Russia.
3 Department of Technosphere Security, Agrarian Technological Institute, Peoples' Friendship University of Russia (RUDN University), 117198, Moscow, Russia.
4 Department of Foreign Languages, Institute of Medicine, Peoples' Friendship University of Russia (RUDN University), 117198, Moscow, Russia.
5 Department of Linguistics and Intercultural Communication of the Faculty of Distance Learning and Part-Time Education of Moscow State Linguistic University, 119034 Moscow, Russia..
Background and Aim: The pathogenesis of staphylococcal infections is mediated by virulence factors, such as enzymes, toxins, and biofilms, which increase the resistance of microorganisms to host immune system evasion. Testing and searching for standardized multi-level algorithms for the indication and differentiation of biofilms at the early stages of diagnosis will contribute to the development of preventive measures to control the critical points of technology and manage dangerous risk factors for the spread of infectious diseases. This research aimed to study the main stages of Staphylococcus aureus biofilm formation in in vitro experiments and to analyze the dynamics of respiratory syndrome development in chickens infected with these bacteria.
Materials and Methods: Experimental reproduction of the infectious process was performed using laboratory models: 10-day-old White Leghorn chickens (n = 20). Before the experiments, the birds were divided into two groups according to the principle of analogs: Group I (control, n = 10): the birds were intranasally inoculated with 0.5 cm3 of 0.9% NaCl solution; Group II (experiment, n = 10): the birds were intranasally inoculated with a suspension of S. aureus bacteria, 0.5 cm3, concentration 1 billion/cm3.
Results: Colonization of individual areas of the substrate under study in vitro occurred gradually from the sedimentation and adhesion of single motile planktonic cells to the attachment stage of microcolony development. Staining preparations with gentian violet due to the “metachromosia” property of this dye are a quick and fairly simple way to differentiate cells and the intercellular matrix of biofilms. Fixation with vapors of glutaraldehyde and osmium tetroxide preserves the natural architecture of biofilms under optical and scanning electron microscopy. Pure cultures of S. aureus microorganisms were isolated from the blood, lungs, small intestine, liver, kidneys, and spleen after 5–10 days during experimental infection of chickens. Clinical signs of respiratory syndrome developed within 5–6 days after infection. Acute and subacute serousfibrinous airsacculitis, characterized by edema and thickening of the membranes of the air sacs and the presence of turbid, watery, foamy contents in the cavity, was the most characteristic pathomorphological sign. The signs of acute congestive hyperemia and one-sided serous-fibrinous pneumonia developed with significant thickening of fibrinous deposits. In Garder’s gland, there was an increase in the number of secretory sections, indicating hypersecretion of the glands. In the lymphoid follicles of Meckel’s diverticulum, leukocytes, usually lymphocytes, and pseudoeosinophils were detected.
Conclusion: Hydration and heteromorphism of the internal environment of biofilms determine the localization of differentiated cells in a three-dimensional matrix for protection against adverse factors. The most characteristic pathomorphological sign was the development of acute and subacute serous-fibrinous airsacculitis when reproducing the infectious process in susceptible models. There was a significant thickening of fibrinous deposits and signs of acute congestive hyperemia and one or two serous-fibrinous pneumonia developed.
Keywords: airsacculitis, avian, biofilm, pathogenesis, respiratory syndrome pneumonia, Staphylococcus aureus.
How to cite this article: Lenchenko E, Sachivkina N, Petrukhina O, Petukhov N, Zharov A, Zhabo N, and Avdonina M (2024) Anatomical, pathological, and histological features of experimental respiratory infection of birds by biofilm-forming bacteria Staphylococcus aureus, Veterinary World, 17(3): 612-619.
Received: 05-12-2023 Accepted: 20-02-2024 Published online: 17-03-2024
Corresponding author: E-mail:
DOI: 10.14202/vetworld.2024.612-619
Copyright: Lenchenko, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/ by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
