Biofilm formation in Streptococcus suis: in vitro impact of serovars and assessment of coinfections with other porcine respiratory disease complex bacterial pathogens.

Streptococcus suis is a worldwide pathogen that impacts the swine industry, causing severe clinical signs, including meningitis and arthritis, in postweaning piglets. A key virulence mechanism of S. suis is biofilm formation, which improves its persistence and resistance to external factors.

TbpB-based oral mucosal vaccine provides heterologous protection against Glässer's disease caused by different serovars of Spanish field isolates of Glaesserella parasuis.

Background: Glaesserella parasuis (G. parasuis) is the primary agent of Glässer's disease, significantly affecting nursery and early fattening piglets. Current prophylactic measures, mainly serovar-specific bacterins administered to sows, are limited by maternal immunity, which can interfere with active immunization in piglets.

Insights into the Virulence and Antimicrobial Resistance of Isolates from Spanish Swine Farms.

is a significant pathogen in swine, primarily causing exudative epidermitis. Addressing infections requires both the characterization of virulence and antimicrobial resistance (AMR) in farm-recovered isolates. This study aimed to characterize the virulence, AMR, and biofilm formation of isolates from Spanish swine farms.

Virulence and Antimicrobial Resistance Characterization of Isolates Recovered from Spanish Swine Farms.

() , the causative agent of Glässer's disease, is present in most pig farms as an early colonizer of the upper respiratory tract. It exhibits remarkable variability in virulence and antimicrobial resistance (AMR), with virulent strains capable of inducing respiratory or systemic disease. This study aimed to characterize the virulence and the AMR profiles in 65 isolates recovered from Spanish swine farms.

Detection of Macrolide and/or Tetracycline Genetic Resistance Determinants by PCR.

Globally, the main molecular trials being developed to study the genetic determinants responsible for conferring resistance to bacterial organisms are amplification-based methods, hybridization-based methods, and sequence-based methods. In the specific case of Streptococcus suis, polymerase chain reaction is the only test tuned up until now for detecting resistant clinical isolates to macrolides and/or tetracyclines, the two main groups of antibiotics being ineffective against this human and animal pathogen.

Analysis of Susceptibility or Resistance to Antimicrobial Agents.

Here were described the main three methods being used for analysis of antibiotic susceptibility or resistance of Streptococcus suis clinical isolates to antimicrobial agents: the Kirby-Bauer disk diffusion, the epsilometer test (E test), and the broth microdilution test. In each case, procedures, results, and interpretation are described, as well as their advantages or limitations when proceeds.

Research Update: Serotype Prevalence and Antimicrobial Resistance Distribution in Swine Isolates Recovered in Spain from 2020 to 2022.

This study aimed to update the serotype distribution in Spain by analysing 302 clinical isolates recovered from diseased pigs between 2020 and 2022. The main objectives were to identify prevalent serotypes, differentiate specific serotypes 1, 14, 2, and 1/2, investigate specific genotypic and phenotypic antimicrobial resistance features, and explore associations between resistance genes and phenotypic resistances. Serotypes 9 (21.

TbpB-Based Vaccine Can Protect Pigs against Glässer's Disease Triggered by SV7 Expressing TbpB Cluster I.

is the etiological agent of Glässer's disease (GD), one of the most important diseases afflicting pigs in the nursery phase. We analyzed the genetic and immunological properties of the TbpB protein naturally expressed by 27 different clinical isolates of that were typed as serovar 7 and isolated from pigs suffering from GD. All the strains were classified as virulent by LS-PCR.

Antimicrobial Resistance Genes in Porcine Are Not Associated with Its Antimicrobial Susceptibility Pattern.

Forty-eight isolates were recovered from porcine pneumonic lungs collected from farms in "Castilla y León" (north-western Spain) in 2017-2019. These isolates were characterized for their minimal inhibition concentrations to twelve antimicrobial agents and for the appearance of eight resistance genes: , , , , , , and . Relevant resistance percentages were shown against tetracyclines (52.

Molecular serotyping of clinical strains of brings new insights regarding Glässer's disease outbreaks in Brazil.

Glässer's disease (GD) is an important infectious disease of swine caused by . Vaccination with inactivated whole cell vaccines is the major approach for prevention of infection worldwide, but the immunity induced is predominantly against the specific polysaccharide capsule. As a consequence, the available vaccines may not induce adequate protection against the field strains, when the capsules present in the vaccine strains are different from those in strains isolated from the farms.

TLR2, Siglec-3 and CD163 expressions on porcine peripheral blood monocytes are increased during sepsis caused by Haemophilus parasuis.

TLRs, Siglecs and CD163 are cell surface receptors that play an important role in immune response and sepsis. The objective of this study was to assess changes in the expression levels of several of these receptors (TLR2, TLR4, CD163, Siglec-1, Siglec-3, Siglec-5 and Siglec-10) on the surface of peripheral blood mononuclear cells from pigs with sepsis caused by Haemophilus parasuis. Flow cytometry was employed to analyze samples from an experimental infection and from cell cultures.

Transcriptomics of Haemophilus (Glässerella) parasuis serovar 5 subjected to culture conditions partially mimetic to natural infection for the search of new vaccine antigens.

Background: Haemophilus (Glässerella) parasuis is the etiological agent of Glässer's disease in pigs. Control of this disorder has been traditionally based on bacterins. The search for alternative vaccines has focused mainly on the study of outer membrane proteins.

Correction to: Mixed-method tutoring support improves learning outcomes of veterinary students in basic subjects.

The original article [1] contains an error whereby Fig. 2a and b are mistakenly swapped with each other, and thus do not correspond to their correct respective sub-headings in the caption.

Mixed-method tutoring support improves learning outcomes of veterinary students in basic subjects.

Background: Tutoring is a useful tool in the university teaching-learning binomial, although its development is impaired in large classes. Recent improvements in information and communication technologies have made tutoring possible via the Internet. The aim of this study was to evaluate the efficacy of mixed-method academic tutoring in two basic subjects in Veterinary Science studies at the University of León (Spain) to optimize the usefulness of tutoring support in the college environment.

New insights about functional and cross-reactive properties of antibodies generated against recombinant TbpBs of Haemophilus parasuis.

Vaccines have become fundamental in the control and elimination of Glässer Disease, a systemic disease of pigs caused by Haemophilus parasuis. The classic vaccines available for prevention of this infection were developed without a robust knowledge about host immunological mechanisms. In this study, we demonstrated the presence of cross-reactive epitopes on both the N-lobe and C-lobe of variants of transferrin binding protein B (TbpBs) expressed on the surface of 6 virulent serovars of H.

Nonbinding site-directed mutants of transferrin binding protein B exhibit enhanced immunogenicity and protective capabilities.

Host-adapted Gram-negative bacterial pathogens from the Pasteurellaceae, Neisseriaceae, and Moraxellaceae families normally reside in the upper respiratory or genitourinary tracts of their hosts and rely on utilizing iron from host transferrin (Tf) for growth and survival. The surface receptor proteins that mediate this critical iron acquisition pathway have been proposed as ideal vaccine targets due to the critical role that they play in survival and disease pathogenesis in vivo. In particular, the surface lipoprotein component of the receptor, Tf binding protein B (TbpB), had received considerable attention as a potential antigen for vaccines in humans and food production animals but this has not translated into the series of successful vaccine products originally envisioned.

Differences in Haemophilus parasuis adherence to and invasion of AOC-45 porcine aorta endothelial cells.

Background: The pathogenesis of Haemophilus parasuis depends on the bacterium's ability to interact with endothelial cells and invade adjacent tissues. In this study, we investigated the abilities of eight H. parasuis reference strains belonging to serovars 1, 2, 4, 5, 7, 9, 10 and 13 to adhere to and invade porcine aortic endothelial cells (AOC-45 cell line).

Immunoproteomic analysis of the protective response obtained with subunit and commercial vaccines against Glässer's disease in pigs.

An immunoproteomic analysis of the protective response of subunit and commercial vaccines in colostrum-deprived pigs against Glässer's disease was carried out. A mixture of proteins with affinity to porcine transferrin (PAPT) from Haemophilus parasuis Nagasaki strain (serovar 5) was inoculated intramuscularly (PAPT(M)) and intratracheally (PAPT(Cp)), along with a commercial bacterin. PAPT were separated using 2 dimensional electrophoresis (2DE) gels and with them, 2DE Western blots were carried out.

Haemophilus parasuis serovar 5 Nagasaki strain adheres and invades PK-15 cells.

Haemophilus parasuis is the agent responsible for causing Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs. The purpose of this study was to investigate the in vitro ability of two H. parasuis serovars of different virulence (serovar 5, Nagasaki strain, highly virulent, belonging to serovar 5, and SW114 strain, nonvirulent, belonging to serovar 3) to adhere to and invade porcine kidney epithelial cells (PK-15 line).

Acute phase protein concentrations in colostrum-deprived pigs immunized with subunit and commercial vaccines against Glässer's disease.

Haemophilus parasuis is the etiological agent of Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs. This study was focused on the characterization of the acute-phase response after immunization and infection of colostrum-deprived pigs with H. parasuis serovar 5, by measuring serum concentrations of three positive acute-phase proteins (APPs) (pig major acute-phase protein pig, MAP; haptoglobin, HPG; C-reactive protein, CRP) and one negative APP (apolipoprotein A-I, ApoA-I).

Evaluation of efficacy of several disinfectants against Campylobacter jejuni strains by a suspension test.

The objective of this study was to determine the efficacy of 16 active compounds and 11 commercial disinfectants against Campylobacter jejuni. Two reference strains (one of avian origin and the other isolated from bovine) and two avian field strains were tested in suspension test in the presence and absence of serum. Chloramine-T, povidone-iodine (1% available iodine), cetylpiridinium chloride, ethanol, isopropanol, chlorhexidine digluconate, formaldehyde, phenol, and 10 of the 11 commercial formulations (eight of them based on quaternary ammonium compounds) showed an excellent disinfectant capability, resulting in the highest level of reduction (>6-log(10)) in colony-forming units of the four C.

Development and characterization of protective Haemophilus parasuis subunit vaccines based on native proteins with affinity to porcine transferrin and comparison with other subunit and commercial vaccines.

Haemophilus parasuis is the agent responsible for causing Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis, and meningitis in pigs. In this study, we have characterized native outer membrane proteins with affinity to porcine transferrin (NPAPT) from H. parasuis serovar 5, Nagasaki strain.

Characterization of a recombinant transferrin-binding protein A (TbpA) fragment from Haemophilus parasuis serovar 5.

Haemophilus parasuis, the etiological agent of Glässer's disease in pigs, possesses iron acquisition pathways mediated by a surface receptor that specifically bind porcine transferrin. This receptor is composed of transferrin-binding protein A (TbpA) and TbpB. As it has been reported for other gram-negative organisms, H.

Nucleotide sequence and transfer properties of two novel types of Actinobacillus pleuropneumoniae plasmids carrying the tetracycline resistance gene tet(H).

Objectives: To analyse the sequence and transfer properties of two tetracycline resistance plasmids found in clinical isolates of Actinobacillus pleuropneumoniae in order to assess their role in the spread of tetracycline resistance.

Methods: The plasmids designated p9956 and p12494 were purified from A. pleuropneumoniae and completely sequenced.

Evaluation of changes in antimicrobial susceptibility patterns of Pasteurella multocida subsp multocida isolates from pigs in Spain in 1987-1988 and 2003-2004.

Objective: To determine the susceptibility of strains of Pasteurella multocida subsp multocida isolated from lung specimens of pigs with pneumonia to 20 antimicrobials and to evaluate the emergence of resistance to those antimicrobials in Spain during the past 2 decades.

Sample Population: 63 isolates recovered from 1987 to 1988 and 132 isolates recovered from 2003 to 2004.

Procedure: A broth microdilution method was used to determine minimal inhibitory concentration (MIC) range and values for MIC50 and MIC90.