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The Journal of Veterinary Medical... Jan 2024Suncus murinus is gaining prominence as a laboratory animal; however, there is no generally accepted method for microbiological monitoring. This study aimed to apply...
Suncus murinus is gaining prominence as a laboratory animal; however, there is no generally accepted method for microbiological monitoring. This study aimed to apply non-serological microbiological monitoring of laboratory mice for S. murinus and identify the subdominant species obtained by culture methods for microbial assessment. Culture and PCR were used to test S. murinus for the laboratory mice test panels including 10 bacterial species and orthohantaviruses, all of which were negative. The species that grew sub-dominantly in rectal feces were identified as Aeromonas hydrophila, which is pathogenic to mammals. These results indicate that microbiological monitoring should be used to detect pathogens directly from S. murinus, not from sentinel animals, due to the host-specific microbial environment.
Topics: Mice; Animals; Animals, Laboratory; Shrews
PubMed: 38008441
DOI: 10.1292/jvms.23-0373 -
Microorganisms Oct 2023is the causative agent of septicemia in fish, and it is associated with significant economic losses in the aquaculture industry. While piscine infections are mainly...
is the causative agent of septicemia in fish, and it is associated with significant economic losses in the aquaculture industry. While piscine infections are mainly treated with antibiotics, the emergence of resistance in bacterial populations requires the development of alternative methods of treatment. The use of phages can be one of them. A novel jumbo phage, AerS_266, was isolated and characterized. This phage infects only mesophilic strains and demonstrates a slow lytic life cycle. Its genome contains 243,674 bp and 253 putative genes: 84 encode proteins with predicted functions, and 3 correspond to tRNAs. Genes encoding two multisubunit RNA polymerases, chimallin and PhuZ, were identified, and AerS_266 was thus defined as a phiKZ-like phage. While similar phages with genomes >200 kb specific to and have been previously described, AerS_266 is the first phiKZ-like phage found to infect .
PubMed: 38004661
DOI: 10.3390/microorganisms11112649 -
Animals : An Open Access Journal From... Nov 2023The objective of this study was to investigate the bactericidal activity of blood plasma from cultured rainbow trout obtained from two different fish farms. Plasma from...
The objective of this study was to investigate the bactericidal activity of blood plasma from cultured rainbow trout obtained from two different fish farms. Plasma from trout naturally infected with the bacterial pathogen was found to inhibit the growth of in vitro. Incubation of in bacteriostatic trout plasma resulted in agglutination and growth retardation, without causing massive damage to the cell membrane. The proteome of the plasma with high antimicrobial activity revealed an abundance of high-density apolipoproteins, some isoforms of immunoglobulins, complement components C1q and C4, coagulation factors, lectins, periostin, and hemoglobin. Analysis of trout proteins retained on cells revealed the presence of fish immunoglobulins, lectins, and complement components on bacteria whose growth was inhibited, although the native membrane attack complex of immunised trout plasma did not assemble effectively, resulting in a weak bactericidal effect. Furthermore, this study examined the bacterial response to trout plasma and suggested that the protein synthesis pathway was the target of antimicrobial proteins from fish blood. Taken together, these findings illustrate the advantages of the affinity approach for understanding the role of plasma proteins in host defence against pathogens.
PubMed: 38003182
DOI: 10.3390/ani13223565 -
Virus Research Jan 2024Aeromonas hydrophila is an opportunistic pathogen that frequently leads to significant mortality in various commercially cultured aquatic species. Bacteriophages offer...
Aeromonas hydrophila is an opportunistic pathogen that frequently leads to significant mortality in various commercially cultured aquatic species. Bacteriophages offer an alternative strategy for pathogens elimination. In this study, we isolated, identified, and characterized a novel temperate A. hydrophila phage, designated as P05B. The bacteriophage P05B is a myovirus based on its morphological features, and possesses the capability to lyse A. hydrophila strains isolated from shrimp. The optimal multiplicity of infection (MOI), adsorption rate, latent period, and burst size for phage P05B were determined to be 0.001, 91.7 %, 20 min, and 483 PFU/cell, respectively. Phage P05B displayed stability across a range of temperatures (28-50 °C) and pH values (4.0-10.0). Sequence analysis unveiled that the genome of phage P05B comprises 32,302 base pairs with an average G + C content of 59.4 %. A total of 40 open reading frames (ORF) were encoded within the phage P05B genome. The comparative genomic analyses clearly implied that P05B might represent a novel species of the genus Bielevirus under Peduoviridae family. A phylogenetic tree was reconstructed, demonstrating that P05B shares a close evolutionary relationship with other Aeromonas and Aeromonas phages. In conclusion, this study increased our knowledge about a new temperate phage of A. hydrophila with strong lytic ability.
Topics: Animals; Bacteriophages; Aeromonas hydrophila; Palaemonidae; Larva; Phylogeny; Ponds; Genome, Viral
PubMed: 37992971
DOI: 10.1016/j.virusres.2023.199279 -
Access Microbiology 2023is an opportunistic pathogen that can cause various infections, including pneumonia, in immunocompromised individuals. This case report presents a rare occurrence of...
INTRODUCTION
is an opportunistic pathogen that can cause various infections, including pneumonia, in immunocompromised individuals. This case report presents a rare occurrence of ventilator-associated pneumonia (VAP) caused by in an apparently non-immunocompromised patient.
CASE PRESENTATION
The patient exhibited signs and symptoms of VAP and was successfully treated with intravenous ciprofloxacin. The discussion highlights the characteristics of species, its virulence factors, risk factors for infection, and antibiotic profile.
CONCLUSION
It emphasizes the need for awareness and suspicion of as a potential cause of VAP in ICU settings, as well as the importance of early detection and appropriate treatment for improved outcomes.
PubMed: 37970092
DOI: 10.1099/acmi.0.000672.v3 -
Animals : An Open Access Journal From... Oct 2023One of the main factors limiting tilapia's production is the occurrence of infections caused by and species. This work intended to evaluate a bivalent vaccine against...
One of the main factors limiting tilapia's production is the occurrence of infections caused by and species. This work intended to evaluate a bivalent vaccine against and by intraperitoneal (i.p) administration in Nile tilapia () in Brazil. The study was carried out in two phases: one in the laboratory, on a small scale, and from the results obtained, the study was expanded to a large scale in a production system in cages. The vaccine proved to be safe and effective in laboratory tests, with a vaccine efficacy (VE) of 93.66%. However, in large-scale tests with 12,000 tilapias, the VE was 59.14%, with a better food conversion ratio (1.54 kg) in the vaccinated group compared to the control group (1.27 kg). These results corroborate the efficiency of this tested vaccine; however, they indicate the need for field tests to attest to real protection.
PubMed: 37958093
DOI: 10.3390/ani13213338 -
Animals : An Open Access Journal From... Oct 2023The use of functional feeds in aquaculture is currently increasing. This study aimed to assess the combined impact of dietary green microalgae and ethanol-inactivated...
The use of functional feeds in aquaculture is currently increasing. This study aimed to assess the combined impact of dietary green microalgae and ethanol-inactivated DCF12.2 (CVP diet) on thick-lipped grey mullet () juvenile fish. The effects on intestinal microbiota and the transcription of genes related to metabolism, stress, and the immune system were investigated after 90 days of feeding. Additionally, the fish were challenged with and polyinosinic-polycytidylic acid (poly I:C) to evaluate the immune response. Microbiota analysis revealed no significant differences in alpha and beta diversity between the anterior and posterior intestinal sections of fish fed the control (CT) and CVP diets. The dominant genera varied between the groups; and were most abundant in the CVP group, whereas , , and were predominant in the CT group. However, microbial functionality remained unaltered. Gene expression analysis indicated notable changes in , , , , and genes in different fish organs on the CVP diet. In the head kidney, gene expression variations were observed following challenges with or poly I:C, with higher peak values seen in fish injected with poly I:C. Moreover, mRNA levels were significantly up-regulated in the CVP group 72 h post- challenge. To conclude, incorporating with in diet affected the microbial species composition in the intestine while preserving its functionality. In terms of gene expression, the combined diet effectively regulated the transcription of stress and immune-related genes, suggesting potential enhancement of fish resistance against stress and infections.
PubMed: 37958080
DOI: 10.3390/ani13213325 -
Animals : An Open Access Journal From... Oct 2023R-(+)-limonene is a monoterpene from plants of the genus with diverse biological properties. This research evaluated the effects of dietary supplementation with...
R-(+)-limonene is a monoterpene from plants of the genus with diverse biological properties. This research evaluated the effects of dietary supplementation with R-(+)-limonene on growth, metabolic parameters in plasma and liver, and the antioxidant and stress responses in silver catfish, , challenged or not with . Fish were fed for 67 days with different doses of R-(+)-limonene in the diet (control 0.0, L0.5, L1.0, and L2.0 mL/kg of diet). On the 60th day, a challenge with was performed. R-(+)-limonene in the diet potentiated the productive performance of the fish. The metabolic and antioxidant responses indicate that R-(+)-limonene did not harm the health of the animals and made them more resistant to the bacterial challenge. Histological findings showed the hepatoprotective effect of dietary R-(+)-limonene against . mRNA levels were upregulated in the liver of fish fed with an L2.0 diet but downregulated with bacterial challenge. The expression levels of mRNA were higher in the brains of fish fed with the L2.0 diet. However, the L2.0 diet downregulated and mRNA expression in the brains of infected fish. In conclusion, the results indicated that R-(+)-limonene can be considered a good dietary supplement for silver catfish.
PubMed: 37958062
DOI: 10.3390/ani13213307 -
BMC Research Notes Nov 2023Eel (Anguilla bicolor bicolor) is an Indonesian export commodity. However, it is facing a problem related to Aeromonas hydrophila, which can cause motile aeromonas...
The potential of shallot skin powder and actinomycetes metabolites as antimicrobe and antibiofilm in the treatment of eel (Anguilla bicolor bicolor) infected with Aeromonas hydrophila.
BACKGROUND
Eel (Anguilla bicolor bicolor) is an Indonesian export commodity. However, it is facing a problem related to Aeromonas hydrophila, which can cause motile aeromonas septicemia (MAS) and produce biofilm formation. Problem with antibiotic resistance challenges the need of an alternative treatment. Therefore, it is important to explore a solution to treat infection and the biofilm formed by A. hydrophila.
OBJECTIVES
In this study, we used shallot skin powder and actinomycetes metabolite 20 PM as antimicrobe and antibiofilm to treated eels infected with A. hydrophila.
RESULTS
Shallot skin powder (6.25 g 100 g feed) and Actinomycetes 20 PM metabolite (2 mL 100 g feed) were found to be effective as antimicrobe and antibiofilm agent in treating eels infected with A. hydrophila. Eel treated with antibiotic, shallot skin powder, and actinomycetes metabolite had 80%, 66%, and 73% survival rates, respectively. Other indicators such as red blood cell count, hemoglobin, and hematocrit were increased, but white blood cell count and phagocytic activity were dropped. Biofilm destruction were analyzed using scanning electron microscopy to determined antibiofilm activity of actinomycetes metabolite against biofilm of A. Hydrophila.
CONCLUSIONS
Shallot skin powder and actinomycetes metabolite were potential to treat infection of A. hydrophila in eel as an alternative treatment to antibiotics.
Topics: Animals; Anguilla; Aeromonas hydrophila; Powders; Shallots; Actinobacteria; Actinomyces; Biofilms; Gram-Negative Bacterial Infections
PubMed: 37946241
DOI: 10.1186/s13104-023-06611-9 -
Frontiers in Microbiology 2023species have been identified as agents responsible for various diseases in both humans and animals. Multidrug-resistant strains pose a significant public health threat...
BACKGROUND
species have been identified as agents responsible for various diseases in both humans and animals. Multidrug-resistant strains pose a significant public health threat due to their emergence and spread in clinical settings and the environment. The aim of this study was to determine a novel resistance mechanism against aminoglycoside antimicrobials in a clinical isolate.
METHODS
The function of was verified by gene cloning and antibiotic susceptibility tests. To explore the activity of the enzyme, recombinant proteins were expressed, and enzyme kinetics were tested. To determine the molecular background and mechanism of , whole-genome sequencing and bioinformatic analysis were performed.
RESULTS
The novel aminoglycoside -acetyltransferase gene confers resistance to several aminoglycosides. Among the antimicrobials tested, ribostamycin showed the highest increase (128-fold) in the minimum inhibitory concentration (MIC) compared with the control strains. According to the MIC results of the cloned , AAC(6')-Va also showed the highest catalytic efficiency for ribostamycin [/ ratio = (3.35 ± 0.17) × 10 M s]. Sharing the highest amino acid identity of 54.68% with AAC(6')-VaIc, the novel aminoglycoside -acetyltransferase constituted a new branch of the AAC(6') family due to its different resistance profiles. The gene context of and its close relatives was conserved in the genomes of species of the genus .
CONCLUSION
The novel resistance gene confers resistance to several aminoglycosides, especially ribostamycin. Our finding of a novel resistance gene in clinical will help us develop more effective treatments for this pathogen's infections.
PubMed: 37920263
DOI: 10.3389/fmicb.2023.1229593