An atypical weakly haemolytic strain of Brachyspira hyodysenteriae is avirulent and can be used to protect pigs from developing swine dysentery
AbstractThe anaerobic intestinal spirochaeteBrachyspira hyodysenteriae colonises the large intestine of pigs and causes swine dysentery (SD), a severe mucohaemorrhagic colitis. SD occurs worldwide, and control is hampered by a lack of vaccines and increasing antimicrobial resistance.B. hyodysenteriae strains typically produce strong beta-haemolysis on blood agar, and the haemolytic activity is thought to contribute to the pathogenesis of SD. Recently, weakly haemolytic variants ofB. hyodysenteriae have been identified in Europe and Australia, and weakly haemolytic strain D28 from Belgium failed to cause disease when used e...
Source: Veterinary Research - June 18, 2019 Category: Veterinary Research Source Type: research

Weaned piglets: another factor to be considered for the control of Salmonella infection in breeding pig farms
AbstractField studies onSalmonella infection in suckling piglets are scarce due to the intrinsic difficulties of collecting proper samples (i.e. tonsils or mesenteric lymph nodes), and most of them rely on the analysis of rectal swabs that limit their accuracy. We used 495 slaughtered 4-weeks-old male piglets intended for human consumption from 5Salmonella-seropositive breeding farms to collect gastrointestinal packages and perform a thorough detection ofSalmonella on mesenteric lymph nodes and intestinal content. The overall prevalence of both infection and shedding was high ( ≈ 36%) indicating that piglets p...
Source: Veterinary Research - June 17, 2019 Category: Veterinary Research Source Type: research

Host intestinal biomarker identification in a gut leakage model in broilers
AbstractIntestinal health problems are a major issue in the poultry industry. Quantifiable easy-to-measure biomarkers for intestinal health would be of great value to monitor subclinical intestinal entities that cause performance problems and to evaluate control methods for intestinal health. The aim of the study was to identify host protein biomarkers for intestinal inflammation and intestinal barrier damage. Proteomic analysis was conducted on ileal and colonic content samples of broilers under an experimental gut damage and inflammation model. Effects of the challenge treatment resulted in a worse gut condition based on...
Source: Veterinary Research - June 17, 2019 Category: Veterinary Research Source Type: research

Bovine milk microbiome: a more complex issue than expected
AbstractThe aim of this study was to analyze bacterial profiles of bovine mastitic milk samples and samples from healthy quarters using Next Generation Sequencing of amplicons from 16S rRNA genes and to compare results with microbiological results by PCR assays of the same samples. A total of 49 samples were collected from one single dairy herd during the same day. The samples were divided in two sample sets, which were used in this study. The DNA extraction as well as the library preparation and sequencing of these two sets were performed separately, and results of the two datasets were then compared. The vast majority of...
Source: Veterinary Research - June 5, 2019 Category: Veterinary Research Source Type: research

Riemerella anatipestifer GldM is required for bacterial gliding motility, protein secretion, and virulence
In this study, Western blotting analysis demonstrated thatR. anatipestifer GldM was localized to the cytomembrane. Further study revealed that the adhesion and invasion capacities of the mutant strain RA2281 (designated Yb2 ΔgldM) in Vero cells and the bacterial loads in the blood of infected ducks were significantly reduced. RNA-Seq and PCR analyses showed that six genes were upregulated and five genes were downregulated in the mutant strain Yb2 ΔgldM and that these genes were mainly involved in the secretion of proteins. Yb2 ΔgldM was also found to be defective in gliding motility and protein secretion....
Source: Veterinary Research - June 3, 2019 Category: Veterinary Research Source Type: research

Hc TTR: a novel antagonist against goat interleukin 4 derived from the excretory and secretory products of Haemonchus contortus
In this study, three proteins, glutathioneS-transferase domain containing protein (HcGST), transthyretin domain containing protein (HcTTR) and calponin actin-binding domain containing protein (HcCab), were identified to bind to goat IL4 by co-immunoprecipitation (Co-IP) assays and yeast two-hybrid screening. Additionally, cell proliferation analysis showed thatHcTTR blocked the IL4-induced proliferation of peripheral blood mononuclear cells in goats, whileHcGST andHcCab did not. In addition,HcTTR could also downregulate the transcription of candidate genes in the IL4-induced JAK/STAT pathway. These results indicated thatHc...
Source: Veterinary Research - June 3, 2019 Category: Veterinary Research Source Type: research

Scrutinizing the triad of Vibrio tapetis , the skin barrier and pigmentation as determining factors in the development of skin ulcerations in wild common dab ( Limanda limanda )
AbstractRecently,Vibrio tapetis was isolated for the first time from skin ulcerations in wild-caught common dab (Limanda limanda). To further examine its role in the development of these skin lesions, an in vivo experiment was performed. The significance of the skin barrier and in addition the difference between pigmented and non-pigmented side were investigated. Hence, the skin of common dab was treated in three different ways on both the pigmented and non-pigmented side. On a first “treatment zone”, the scales and overlying epidermal tissue were removed whereas in a second zone only the mucus was discarded. T...
Source: Veterinary Research - June 2, 2019 Category: Veterinary Research Source Type: research

Characterization of the non-glandular gastric region microbiota in Helicobacter suis -infected versus non-infected pigs identifies a potential role for Fusobacterium gastrosuis in gastric ulceration
AbstractHelicobacter suis has been associated with development of gastric ulcers in the non-glandular part of the porcine stomach, possibly by affecting gastric acid secretion and altering the gastric microbiota.Fusobacterium gastrosuis is highly abundant in the gastric microbiota ofH. suis-infected pigs and it was hypothesized that this micro-organism could play a role in the development of gastric ulceration. The aim of this study was to obtain further insights in the influence of a naturally acquiredH. suis infection on the microbiota of the non-glandular part of the porcine stomach and in the pathogenic potential ofF. ...
Source: Veterinary Research - May 23, 2019 Category: Veterinary Research Source Type: research

The CpxR regulates type VI secretion system 2 expression and facilitates the interbacterial competition activity and virulence of avian pathogenic Escherichia coli
This study broadens understanding of the regulatory effect of Cpx TCS, thus elucidating the mechanisms through which Cpx TCS involved in bacterial virulence. (Source: Veterinary Research)
Source: Veterinary Research - May 23, 2019 Category: Veterinary Research Source Type: research

Correlation between footpad lesions and systemic bacterial infections in broiler breeders
AbstractFootpad lesions are an important factor in evaluation of animal welfare in broilers regulated by law; however, no legal requirements have been set for the parent birds. Nevertheless, the present study confirms that foot health in broiler breeders declines significantly with increasing age, thus potentially impairing the animal welfare due to pain and discomfort from footpad dermatitis. Furthermore, this is the first report demonstrating a correlation between the presence of footpad lesions and systemic bacterial infections with Gram-positive cocci in broiler breeder birds. (Source: Veterinary Research)
Source: Veterinary Research - May 21, 2019 Category: Veterinary Research Source Type: research

Longitudinal field studies reveal early infection and persistence of influenza A virus in piglets despite the presence of maternally derived antibodies
AbstractA longitudinal study was performed in three Danish farrow to grower (30 kilos) herds over a 4-month period to investigate the dynamics and clinical impacts of influenza A virus (IAV) infections. In each herd, four batches consisting of four sows each with five ear-tagged piglets were included. Nasal swabs and/or blood were sampled from the sows and/or the piglets prior to farrowing and at weeks 1, 3, and 5 and at the end of the nursery period. Clinical examinations were performed at each sampling time. The sows and piglets were tested for IAV and IAV antibodies in nasal swabs and blood samples, respectively. The re...
Source: Veterinary Research - May 21, 2019 Category: Veterinary Research Source Type: research

Hemagglutinin-neuraminidase and fusion proteins of virulent Newcastle disease virus cooperatively disturb fusion –fission homeostasis to enhance mitochondrial function by activating the unfolded protein response of endoplasmic reticulum and mitochondrial stress
AbstractThe fusogenically activated F and HN proteins of virulent NDV induce complete autophagic flux in DF-1 and A549 cells. However, the effect of both glycoproteins on mitochondria remains elusive. Here, we found that F and HN cooperation increases mitochondrial biogenesis but does not cause the mitochondria damage. We observed that both glycoproteins change the morphological characteristics and spatial distribution of intracellular mitochondria. F and HN cooperate cooperatively to induce ER stress and UPRmt. Our preliminary data suggested that F and HN cooperatively disturb mitochondrial fusion –fission homeostas...
Source: Veterinary Research - May 21, 2019 Category: Veterinary Research Source Type: research

The first reptilian circovirus identified infects gut and liver tissues of black-headed pythons
AbstractViral metagenomic analysis of the liver of a black headed python (Aspidites melanocephalus) euthanized for a proliferative spinal lesion of unknown etiology yielded the first characterized genome of a reptile-infecting circovirus (black-headed python circovirus or BhPyCV). BhPyCV-specific in situ hybridization (ISH) showed that viral nucleic acids were strongly expressed in the intestinal lining and mucosa and multifocally in the liver. To investigate the presence of this virus in other snakes and its possible pathogenicity, 17 snakes in the python family with spinal disease were screened with ISH yielding a second...
Source: Veterinary Research - May 15, 2019 Category: Veterinary Research Source Type: research

Quantifying bluetongue vertical transmission in French cattle from surveillance data
AbstractBluetongue is a vector-borne disease of ruminants with economic consequences for the livestock industry. Bluetongue virus serotype 8 (BTV-8) caused a massive outbreak in Europe in 2006/2009 and re-emerged in France in 2015. Given the unprecedented epidemiological features of this serotype in cattle, the importance of secondary routes of transmission was reconsidered and transplacental transmission of BTV-8 was demonstrated in naturally and experimentally infected cattle. Here we used surveillance data from the on-going outbreak to quantify BTV-8 vertical transmission in French cattle. We used RT-PCR pre-export test...
Source: Veterinary Research - May 13, 2019 Category: Veterinary Research Source Type: research

Knowledge and risk factors for foot-and-mouth disease among small-scale dairy farmers in an endemic setting
This study reports risk factors associated with clinical FMD at the farm level in a densely populated smallholder farming area of Kenya. These results can be used to inform the development of risk-based strategic plans for FMD control and as a baseline for evaluating interventions and control strategies. (Source: Veterinary Research)
Source: Veterinary Research - May 13, 2019 Category: Veterinary Research Source Type: research

Acetate metabolic requirement of avian pathogenic Escherichia coli promotes its intracellular proliferation within macrophage
In this study, we identified that APECacs-yjcH-actP operon, encoding acetate assimilation system, presented the host-induced transcription during its proliferation in macrophages. Our result showed that this acetate assimilation system acted as a novel intracellular survival factor to promote APEC replication within macrophages. Furthermore, deletion ofacs-yjcH-actP operon in APEC decreased its cytotoxic level to macrophages. qRT-PCR results showed that the production of pro-inflammatory cytokines (IL-1 β, IL-6, IL-8, IL-12β, and TNF-α) and iNOS in FY26∆acs-yjcH-actP infected macrophages were obviously do...
Source: Veterinary Research - May 1, 2019 Category: Veterinary Research Source Type: research

Spleen and head kidney differential gene expression patterns in trout infected with Lactococcus garvieae correlate with spleen granulomas
AbstractLactococcus garvieae is a significant pathogen in aquaculture with a potential zoonotic risk. To begin to characterize the late immune response of trout to lactococcosis, we selected infected individuals showing clinical signs of lactococcosis. At the time lactococcosis clinical signs appeared, infection byL. garvieae induced a robust inflammatory response in the spleen of rainbow trout, which correlated with abundant granulomatous lesions. The response in kidney goes in parallel with that of spleen, and most of the gene regulations are similar in both organs. A correlation existed between the early inflammatory gr...
Source: Veterinary Research - May 1, 2019 Category: Veterinary Research Source Type: research

Neighbourhood contacts and trade movements drive the regional spread of bovine viral diarrhoea virus (BVDV)
AbstractTo explore the regional spread of endemic pathogens, investigations are required both at within and between population levels. The bovine viral diarrhoea virus (BVDV) is such a pathogen, spreading among cattle herds mainly due to trade movements and neighbourhood contacts, and causing an endemic disease with economic consequences. To assess the contribution of both transmission routes on BVDV regional and local spread, we developed an original epidemiological model combining data-driven and mechanistic approaches, accounting for heterogeneous within-herd dynamics, animal movements and neighbourhood contacts. Extens...
Source: Veterinary Research - April 28, 2019 Category: Veterinary Research Source Type: research

UBXN1 interacts with the S1 protein of transmissible gastroenteritis coronavirus and plays a role in viral replication
AbstractTransmissible gastroenteritis coronavirus (TGEV) is an enteropathogenic coronavirus that causes diarrhea in pigs and is associated with high morbidity and mortality in sucking piglets. S1 is one of two protein domains in the spike (S) glycoprotein and is responsible for enteric tropism, sialic acid recognition, and host receptor binding. Although there has been extensive research on the S1 protein of TGEV, little is known about the intracellular role of TGEV-S1. In the present study, we used yeast two-hybrid screening of a cDNA library from porcine intestinal cells to identify proteins that interact with TGEV-S1. A...
Source: Veterinary Research - April 26, 2019 Category: Veterinary Research Source Type: research

Impacts of breed type and vaccination on Teladorsagia circumcincta infection in native sheep in Gran Canaria
AbstractVaccines and genetic resistance offer potential future alternatives to the exclusive use of anthelmintics to control gastrointestinal nematodes (GIN). Here, aTeladorsagia circumcincta prototype vaccine was administered to two sheep breeds which differ in their relative levels of resistance to infection with GIN. Vaccination of the more susceptible Canaria Sheep (CS) breed induced significant reductions in worm length and numbers of worm eggs in utero (EIU) when compared to control CS sheep. In the more resistant Canaria Hair Breed (CHB), although vaccination induced a reduction in all parasitological parameters ana...
Source: Veterinary Research - April 26, 2019 Category: Veterinary Research Source Type: research

Newcastle disease virus selectively infects dividing cells and promotes viral proliferation
AbstractNewcastle disease virus (NDV) can select cells to infect, but the mechanism of its cell selectivity has not been comprehensively investigated. Here, we use HeLa cells to establish that NDV can selectively infect cells at the single-cell level. We labeled proliferating cells with 5 ′-bromo-2-deoxyuridine (BrdU) and examined the colocalization of BrdU with NDV in cells to clarify the relationships between NDV infection and cell proliferation. Receptors at the plasma membrane mediate NDV entry into host cells. We labeled sialic acid receptor isoforms, compared their densities between different cell types and mea...
Source: Veterinary Research - April 17, 2019 Category: Veterinary Research Source Type: research

Thioredoxin H (TrxH) contributes to adversity adaptation and pathogenicity of Edwardsiella piscicida
In this study, we characterized TrxH ofE. piscicida (named TrxHEp) and examined its expression and function. TrxHEp is composed of 125 residues and possesses typical thioredoxin H motifs. Expression oftrxHEp was upregulated under conditions of oxidative stress, iron starvation, low pH, and during infection of host cells.trxHEp expression was also regulated by ferric uptake regulator (Fur), an important global regulatory ofE. piscicida. Compared to the wild type TX01, a markerlesstrxHEp in-frame mutant strain TX01 ∆trxH exhibited markedly compromised tolerance of the pathogen to hydrogen peroxide, acid stress, and iron de...
Source: Veterinary Research - April 14, 2019 Category: Veterinary Research Source Type: research

Bovine fetal mesenchymal stem cells exert antiproliferative effect against mastitis causing pathogen Staphylococcus aureus
AbstractStaphylococcus aureus is the most commonly isolated pathogen from clinical bovine mastitis samples and a difficult pathogen to combat. Mesenchymal stem cells (MSC) are multipotent progenitor cells equipped with a variety of factors that inhibit bacterial growth. The aim of the present study was to evaluate the in vitro antibacterial potential againstS. aureus of conditioned medium (CM) from MSC derived from fetal bovine bone marrow (BM-MSC) and adipose tissue (AT-MSC). BM-MSC, AT-MSC and fetal fibroblasts (FB) cultures were activated by infection withS. aureus. Bacterial growth was evaluated in presence of CM, conc...
Source: Veterinary Research - April 10, 2019 Category: Veterinary Research Source Type: research

Evidence that the stress hormone cortisol regulates biofilm formation differently among Flavobacterium columnare isolates
AbstractThe impact of cortisol onFlavobacterium columnare biofilm formation was explored. Firstly, the dynamics of biofilm formation by one highly (HV) and one low virulent (LV)F. columnare isolate with and without the stress hormone cortisol under microfluidic flow conditions was characterized. This to confirm thatF. columnare cells could form biofilm under cortisol supplementation, and to compare the temporal and structural differences between different treatment groups. One trial revealed that in both isolates cell aggregates resembling biofilms occurred within 7-h post-inoculation. Consequently, cell clusters were slou...
Source: Veterinary Research - April 10, 2019 Category: Veterinary Research Source Type: research

Comprehensive analysis of miRNA profiles reveals the role of Schistosoma japonicum miRNAs at different developmental stages
AbstractSchistosomiasis is an important zoonotic disease affecting up to 40 kinds of animals and 250 million people. It has been reported that the miRNAs play a role in the metabolism, differentiation, development and reproduction in many organisms. However, the roles of miRNAs regulating the development, maturation and production in schistosome in both females and males remains unclear. Here we present the dynamic transcriptome analysis of all 79 knownSchistosoma japonicum miRNAs from pairing to production, including 14  days post-infection (dpi), 16, 18, 20, 22, 24, 26, 28 dpi female and male, by small RNA sequ...
Source: Veterinary Research - April 3, 2019 Category: Veterinary Research Source Type: research

Nuclear localization of Newcastle disease virus matrix protein promotes virus replication by affecting viral RNA synthesis and transcription and inhibiting host cell transcription
In this study, the potential functions of the M protein in the nucleus were investigated. We first demonstrate that nuclear localization of the M protein could not only promote the cytopathogenicity of NDV but also increase viral RNA synthesis and transcription efficiency in DF-1 cells. Using microarray analysis, we found that nuclear localization of the M protein might inhibit host cell transcription, represented by numerous up-regulating genes associated with transcriptional repressor activity and down-regulating genes associated with transcriptional activator activity. The role of representative up-regulated gene prospe...
Source: Veterinary Research - March 19, 2019 Category: Veterinary Research Source Type: research

Weakly haemolytic variants of Brachyspira hyodysenteriae newly emerged in Europe belong to a distinct subclade with unique genetic properties
In this study, 34 European whBh and 82 strongly haemolytic isolates were subjected to comparative genomic analysis. A phylogenetic tree constructed using core single nucleotide polymorphisms showed that the whBh formed a distinct sub-clade. All eight genes previously associated with haemolysis inB. hyodysenteriae were present in the whBh. No consistent patterns of amino acid substitutions for all whBh were found in these genes. In contrast, a genome region containing six coding sequences (CDSs) had consistent nucleotide sequence differences between strongly and whBh isolates. Two CDSs were predicted to encode ABC transport...
Source: Veterinary Research - March 6, 2019 Category: Veterinary Research Source Type: research

A balanced game: chicken macrophage response to ALV-J infection
In this study, we discovered an interesting phenomenon: ALV-J replication is weakened from 3  hours post-infection (hpi) to 36 hpi, which was verified using Western blotting and RT-PCR. To further investigate the interaction between ALV-J and macrophages, transcriptome analysis was performed to analyze the host genes’ function in chicken primary monocyte-derived macrophages (MDM). Compa red to the uninfected control, 624 up-regulated differentially expressed genes (DEG) and 341 down-regulated DEG at 3 hpi, and 174 up-regulated DEG and 87 down-regulated DEG at 36 hpi were identified in chicken MDM, respectiv...
Source: Veterinary Research - March 5, 2019 Category: Veterinary Research Source Type: research

PCV2 replication promoted by oxidative stress is dependent on the regulation of autophagy on apoptosis
AbstractPorcine circovirus type 2 (PCV2) is an economically important swine pathogen but some extra trigger factors are required for the development of PCV2-associated diseases. By evaluating cap protein expression, viral DNA copies and the number of infected cells, the present study further confirmed that oxidative stress can promote PCV2 replication. The results showed that oxidative stress induced autophagy in PCV2-infected PK15 cells. Blocking autophagy with inhibitor 3-methyladenine or ATG5-specific siRNA significantly inhibited oxidative stress-promoted PCV2 replication. Importantly, autophagy inhibition significantl...
Source: Veterinary Research - March 4, 2019 Category: Veterinary Research Source Type: research

Study of the underlying mechanisms and consequences of pathogenicity differences between two in vitro selected G1-H9N2 clones originating from a single isolate
AbstractThe G1-H9N2 avian influenza virus (AIV) has caused significant economic losses in the commercial poultry industry due to reduced egg production and increased mortality. The field observations have shown that H9N2 viruses circulate and naturally mix with other pathogens and these simultaneous infections can exacerbate disease. To avoid an incorrect virus characterization, due to co-infection, isolates were purified by in vitro plaque assays. Two plaque purified G1-H9N2 clones, selected on different cell types, named MDCK-and CEF-clone in regards to the cell culture used, were studied in vivo, revealing two different...
Source: Veterinary Research - March 1, 2019 Category: Veterinary Research Source Type: research

Suppression of lymphocyte apoptosis in spleen by CXCL13 after porcine circovirus type 2 infection and regulatory mechanism of CXCL13 expression in pigs
In this study, we found that the YL pigs showed more severe lymphocyte apoptosis and higher viral load in the spleen tissue than LW pigs. To illustrate the differential gene expression between healthy and infected spleens, transcriptome profiling of spleen tissues from PC V2-infected and control YL pigs was compared by RNA sequencing. A total of 90 differentially expressed genes (DEGs) was identified, includingCD207,RSAD2,OAS1,OAS2,MX2,ADRB3,CXCL13,CCR1, andADRA2C, which were significantly enriched in gene ontology (GO) terms related to the defense response to virus and cell –cell signaling, and another nine DEGs,KLF...
Source: Veterinary Research - February 28, 2019 Category: Veterinary Research Source Type: research

14-3-3 ε acts as a proviral factor in highly pathogenic porcine reproductive and respiratory syndrome virus infection
AbstractThe highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) emerged in 2006 in China and caused great economic losses for the swine industry because of the lack of an effective vaccine. 14-3-3 proteins are generating significant interest as potential drug targets by allowing the targeting of specific pathways to elicit therapeutic effects in human diseases. In a previous study, 14-3-3s were identified to interact with non-structural protein 2 (NSP2) of PRRSV. In the present study, the specific subtype 14-3-3 ε was confirmed to interact with NSP2 and play a role in the replication of...
Source: Veterinary Research - February 28, 2019 Category: Veterinary Research Source Type: research

In-feed resin acids reduce matrix metalloproteinase activity in the ileal mucosa of healthy broilers without inducing major effects on the gut microbiota
AbstractThe chicken gut is constantly exposed to harmful molecules and microorganisms which endanger the integrity of the intestinal wall. Strengthening intestinal mucosal integrity is a key target for feed additives that aim to promote intestinal health in broilers. Recently, dietary inclusion of resin-based products has been shown to increase broiler performance. However, the mode of action is still largely unexplored. Coniferous resin acids are known for their anti-microbial, anti-inflammatory and wound-healing properties, all properties that might support broiler intestinal health. In the current study, the effect of p...
Source: Veterinary Research - February 22, 2019 Category: Veterinary Research Source Type: research

Piscine orthoreovirus subtype 3 (PRV-3) causes heart inflammation in rainbow trout ( Oncorhynchus mykiss )
In this study, we conducted a 10-week long experimental infection trial in rainbow trout with purified PRV-3 particles to assess the causal relationship between the virus and development of heart inflammation. The monitoring the PRV-3 load in heart and spleen by RT-qPCR shows a progressive increase of viral RNA to a peak, followed by clearance without a measurable change in haematocrit. The development of characteristic cardiac histopathological findings occurred in the late phase of the trial and was associated with increased expression of CD8+, indicating cytotoxic T cell proliferation. The findings indicate that, under ...
Source: Veterinary Research - February 18, 2019 Category: Veterinary Research Source Type: research

Unravelling the first key steps in equine herpesvirus type 5 (EHV5) pathogenesis using ex vivo and in vitro equine models
AbstractEquine herpesvirus type 5 (EHV5) is a ubiquitous, yet obscure pathogen in the horse population and is commonly associated with fatal equine multinodular pulmonary fibrosis (EMPF). To date, little is known about the precise pathogenesis of EHV5. Here, we evaluated the dynamics of EHV5 infection in representative ex vivo and in vitro equine models, using immunofluorescence staining and virus titration. EHV5 was unable to infect epithelial cells lining the mucosa of nasal and tracheal explants. Similarly, primary equine respiratory epithelial cells (EREC) were not susceptible to EHV5 following inoculation at the apica...
Source: Veterinary Research - February 18, 2019 Category: Veterinary Research Source Type: research

Development of a recombinant Newcastle disease virus-vectored vaccine for infectious bronchitis virus variant strains circulating in Egypt
AbstractInfectious bronchitis virus (IBV) causes a major disease problem for the poultry industry worldwide. The currently used live-attenuated vaccines have the tendency to mutate and/or recombine with circulating field strains resulting in the emergence of vaccine-derived variant viruses. In order to circumvent these issues, and to develop a vaccine that is more relevant to Egypt and its neighboring countries, a recombinant avirulent Newcastle disease virus (rNDV) strain LaSota was constructed to express the codon-optimized S glycoprotein of the Egyptian IBV variant strain IBV/Ck/EG/CU/4/2014 belonging to GI-23 lineage, ...
Source: Veterinary Research - February 11, 2019 Category: Veterinary Research Source Type: research

Gammaherpesvirus BoHV-4 infects bovine respiratory epithelial cells mainly at the basolateral side
AbstractBovine herpesvirus 4 (BoHV-4) is a gammaherpesvirus that is widespread in cattle. However, only a few studies about the pathogenesis of BoHV-4 primary infection have been reported. In the present study, ex vivo models with bovine nasal and tracheal mucosa explants were used to study the cellular BoHV-4-host interactions. Infection was observed in nasal but not in tracheal epithelial cells. To find a possible correlation between the integrity and restricted infection of the respiratory epithelium, both nasal mucosal and tracheal explants were treated with EGTA, a drug that disrupts the intercellular junctions, befor...
Source: Veterinary Research - February 8, 2019 Category: Veterinary Research Source Type: research

Reproduction of contagious caprine pleuropneumonia reveals the ability of convalescent sera to reduce hydrogen peroxide production in vitro
AbstractContagious caprine pleuropneumonia (CCPP), caused byMycoplasma capricolum subsp.capripneumoniae is a severe disease widespread in Africa and Asia. Limited knowledge is available on the pathogenesis of this organism, mainly due to the lack of a robust in vivo challenge model and the means to do site-directed mutagenesis. This work describes the establishment of a novel caprine challenge model for CCPP that resulted in 100% morbidity using a combination of repeated intranasal spray infection followed by a single transtracheal infection employing the recent Kenyan outbreak strain ILRI181. Diseased animals displayed CC...
Source: Veterinary Research - February 8, 2019 Category: Veterinary Research Source Type: research

Role of p53 in pseudorabies virus replication, pathogenicity, and host immune responses
AbstractAs a key cellular transcription factor that plays a central role in cellular responses to a broad range of stress factors, p53 has generally been considered as a host cell restriction factor for various viral infections. However, the defined roles of p53 in pseudorabies virus (PRV) replication, pathogenesis, and host responses remain unclear. In the present study, we initially constructed a p53 overexpressing a porcine kidney epithelial cell line (PK-15) to detect the effect of p53 on PRV replication in vitro. The results show that viral glycoprotein B (gB) gene copies and the titers of virus were significantly hig...
Source: Veterinary Research - February 4, 2019 Category: Veterinary Research Source Type: research

Saccharomyces cerevisiae mannan induces sheep beta-defensin-1 expression via Dectin-2-Syk-p38 pathways in ovine ruminal epithelial cells
AbstractThe rumen epithelium of sheep serves as an immune interface with the environment and secretes antimicrobial peptides with bactericidal function against various pathogens. Sheep beta-defensin-1 (SBD-1), an antimicrobial peptide, is secreted from ovine ruminal epithelial cells (OREC) in response to microbial infections. Mannan, the main component of theSaccharomyces cerevisiae cell wall can stimulate innate and regulatory immune responses that could improve the gastrointestinal environment. We aimed at investigating the effects of mannan on SBD-1 expression and the downstream signaling pathways stimulated in OREC. We...
Source: Veterinary Research - February 4, 2019 Category: Veterinary Research Source Type: research

Transcriptome analysis unraveled potential mechanisms of resistance to Haemonchus contortus infection in Merino sheep populations bred for parasite resistance
AbstractHaemonchus contortus is one of the most pathogenic gastrointestinal nematodes in small ruminants. To understand molecular mechanisms underlying host resistance to this parasite, we used RNA-sequencing technology to compare the transcriptomic response of the abomasal tissue, the site of the host-parasite interaction, of Merino sheep bred to be either genetically resistant or susceptible toH. contortus infection. Two different selection flocks, theHaemonchus selection flock (HSF) and theTrichostrongylus selection flock (TSF), and each contains a resistant and susceptible line, were studied. The TSF flock was seemingl...
Source: Veterinary Research - January 24, 2019 Category: Veterinary Research Source Type: research

Transmission studies of chronic wasting disease to transgenic mice overexpressing human prion protein using the RT-QuIC assay
AbstractChronic wasting disease (CWD) is a fatal prion disease which infects deer, elk and moose. CWD was first described as a wasting syndrome in captive deer in Colorado and Wyoming wildlife facilities from 1967 to 1979. Currently, CWD has been reported in 26 states of the USA, three Canadian provinces, South Korea, Norway and Finland. Since human consumption of cervids is common, it is critical to determine if CWD can infect humans. Published research, including epidemiologic studies and transmission studies using animal models, including transgenic mice that express human prion protein, have suggested existence of a st...
Source: Veterinary Research - January 22, 2019 Category: Veterinary Research Source Type: research

Antiviral activity of itraconazole against type I feline coronavirus infection
In this study, we demonstrated that itraconazole (ICZ), practically used for fungal infections in cats, inhibits the type I FCoV infection. ICZ also exhibited antiviral effect in cells after viral in fection, suggesting that ICZ could potentially be used as a therapeutic. (Source: Veterinary Research)
Source: Veterinary Research - January 18, 2019 Category: Veterinary Research Source Type: research

Long-term avian influenza virus epidemiology in a small Spanish wetland ecosystem is driven by the breeding Anseriformes community
AbstractDuring 2007 –2009 and 2012–2014, avian influenza virus (AIV) was studied in a wild avian community of a northern Spanish wetland using non-invasive sampling methods and host identification byCOI barcoding. The aim of this longitudinal study was to evaluate AIV dynamics in a natural wetland ecosystem, taking into account both virological aspects and ecological traits of hosts. Global AIV prevalence decreased significantly during the second sampling period (0.3%) compared to the first (6.6%). Circulating subtype distributions were also different between periods, with a noteworthy H5 and H7 subtype richnes...
Source: Veterinary Research - January 17, 2019 Category: Veterinary Research Source Type: research

Effect of anacardic acid against echinococcosis through inhibition of VEGF-induced angiogenesis
AbstractEchinococcosis is a zoonotic infection caused by cestode species of the genusEchinococcus, with limited treatment options. It is urgent to develop new anti-hydatid agent. In this paper, we reported anacardic acid (AA), a natural product isolated from the Brazilian cashew-nut shell liquid, which presented a high activity against metacestodes ofEchinococcus multilocularis (E. multilocularis) andEchinococcus granulosus sensu stricto (E. granulosus s.s.) in vitro and in vivo. AA exerted a better efficacy onE. granulosus s.s. protoscoleces andE. multilocularis metacestodes than that of albendazole (ABZ) and dihydroartem...
Source: Veterinary Research - January 14, 2019 Category: Veterinary Research Source Type: research

CD4: a vital player in the teleost fish immune system
AbstractCD4 is a nonpolymorphic transmembrane glycoprotein molecule that is expressed on the surface of T-helper cells and plays an essential role in the immune response. It functions as a coreceptor with the T-cell receptor by binding to major histocompatibility complex class II on the surface of dendritic cells that present antigens. CD4+ T cells hold a key position in coordinating the immune system through production of several cytokines after activation and differentiation. The CD4+ T helper subtypes (T-helper 1, T-helper 2, T-helper 17, T-helper 9, and regulatory-T cells) perform different immune functions subsequent ...
Source: Veterinary Research - January 7, 2019 Category: Veterinary Research Source Type: research

Development of a live attenuated trivalent porcine rotavirus A vaccine against disease caused by recent strains most prevalent in South Korea
AbstractPorcine rotaviruses cause severe economic losses in the Korean swine industry due to G- and P-genotype mismatches between the predominant field and vaccine strains. Here, we developed a live attenuated trivalent porcine group A rotavirus vaccine using 80 cell culture passages of the representative Korean predominant strains G8P[7] 174-1, G9P[23] PRG942, and G5P[7] K71. Vaccination with the trivalent vaccine or its individual components induced no diarrhea during the first 2  weeks post-vaccination, i.e., the vaccines were attenuated. Challenge of trivalent-vaccinated or component-vaccinated piglets with homolo...
Source: Veterinary Research - January 7, 2019 Category: Veterinary Research Source Type: research

Gut colonization by a novel Clostridium species is associated with the onset of epizootic rabbit enteropathy
AbstractEpizootic rabbit enteropathy (ERE) represents one of the most devastating diseases affecting rabbit farms. Previous studies showing transmissibility of disease symptoms through oral inoculation of intestinal contents from sick animals suggested a bacterial infectious origin for ERE. However, no etiological agent has been identified yet. On the other hand, ERE is associated with major changes in intestinal microbial communities, pinpointing dysbiosis as an alternative cause for the disease. To better understand the role of intestinal bacteria in ERE development, we have performed a prospective longitudinal study in ...
Source: Veterinary Research - December 20, 2018 Category: Veterinary Research Source Type: research

Low levels of classical BSE infectivity in rendered fat tissue
This study, although not representative, provides a proof of principle, indicating the potential contamination of melted mesenteric fat by embedded nervous structures during standard tallow production. (Source: Veterinary Research)
Source: Veterinary Research - December 20, 2018 Category: Veterinary Research Source Type: research

Regulators of Salmonella -host interaction identified by peripheral blood transcriptome profiling: roles of TGFB1 and TRP53 in intracellular Salmonella replication in pigs
AbstractPeripheral blood transcriptome is an important intermediate data source for investigating the mechanism ofSalmonella invasion, proliferation, and transmission. We challenged 4-week old piglets withSalmonella enterica serovar Typhimurium LT2 and investigated the peripheral blood gene expression profile before treatment (d0) and at 2 and 7  days post-inoculation (dpi) using deep sequencing. Regulator pathways were first predicted in silico and validated by wet-lab experiments. In total, 1255, 765, and 853 genes were differentially expressed between 2 dpi/d0, 7 dpi/d0, and 7 dpi/2 dpi, respectively. Additionally,...
Source: Veterinary Research - December 12, 2018 Category: Veterinary Research Source Type: research