Evaluation of the immunogenicity and efficacy of BCG and MTBVAC vaccines using a natural transmission model of tuberculosis
In this study, we evaluated the immunogenicity and efficacy of two attenuated vaccines, BCG and MTBVAC, after each was given to 17 goats (2  months old) and then exposed for 9 months to goats infected withM. caprae. In general, MTBVAC-vaccinated goats showed higher interferon-gamma release than BCG vaccinated goats in response to bovine protein purified derivative and ESAT-6/CFP-10 antigens and the response was significantly higher than that observed in the control group until challenge. All animals showed lesions consistent with TB at the end of the study. Goats that received either vaccine showed significantly ...
Source: Veterinary Research - October 15, 2019 Category: Veterinary Research Source Type: research

Correction to: Effects of  challenge dose and inoculation route of the virulent Neospora caninum Nc-Spain7 isolate in pregnant cattle at mid-gestation
In the original publication of this article [1], there are error in the Fig.  5, the “ml” should be replaced by “mL” (Fig. 5A) and “IFNγ” should be “IFN-γ” in Fig. 5A, B. The correct figure is below: (Source: Veterinary Research)
Source: Veterinary Research - October 14, 2019 Category: Veterinary Research Source Type: research

Bovine ephemeral fever virus triggers autophagy enhancing virus replication via upregulation of the Src/JNK/AP1 and PI3K/Akt/NF- κB pathways and suppression of the PI3K/Akt/mTOR pathway
AbstractAutophagy plays an important role in cellular response to pathogens. However, the impact of the autophagy machinery on bovine ephemeral fever virus (BEFV) infection is not yet determined. A recent study in our laboratory demonstrated that BEFV triggers simultaneously the PI3K/Akt/NF- κB and Src/JNK-AP1 pathways in the stage of virus binding to enhance virus entry. In this work, we report that BEFV induces autophagy via upregulation of the PI3K/Akt/NF-κB and Src/JNK/AP1 pathways in the early to middle stages of infection and suppresses the PI3K/Akt/mTOR pathway at the late stag e of infection. To activat...
Source: Veterinary Research - October 10, 2019 Category: Veterinary Research Source Type: research

Recent advances in delivery of veterinary DNA vaccines against avian pathogens
AbstractVeterinary vaccines need to have desired characteristics, such  as being effective, inexpensive, easy to administer, suitable for mass vaccination and stable under field conditions. DNA vaccines have been proposed as potential solutions for poultry diseases since they are subunit vaccines with no risk of infection or reversion to virulence. DNA vaccines can be utilized for simultaneous immunizations against multiple pathogens and are relatively easy to design and inexpensive to manufacture and store. Administration of DNA vaccines has been shown to stimulate immune responses and provide protection from challen...
Source: Veterinary Research - October 10, 2019 Category: Veterinary Research Source Type: research

Role of neuromedin B and its receptor in the innate immune responses against influenza A virus infection in vitro and in vivo
AbstractThe peptide neuromedin B (NMB) and its receptor (NMBR) represent a system (NMB/NMBR) of neuromodulation. Here, it was demonstrated that the expression of NMBR in cells or murine lung tissues was clearly upregulated in response to H1N1/PR8 influenza A virus infection. Furthermore, the in vitro and in vivo activities of NMB/NMBR during PR8 infection were investigated. It was observed that A549 cells lacking endogenous NMBR were more susceptible to virus infection than control cells, as evidenced by the increased virus production in the cells. Interestingly, a significant decrease in IFN- α and increased IL-6 ex...
Source: Veterinary Research - October 10, 2019 Category: Veterinary Research Source Type: research

Virus persistence in pig herds led to successive reassortment events between swine and human influenza A viruses, resulting in the emergence of a novel triple-reassortant swine influenza virus
This study illustrates how recurrent influenza infections increase the co-infection risk and facilitate evolutionary jumps by successive gene exchanges. It recalls the importance of appropriate biosecurity measures inside holdings to limit virus persistence and interspecies transmissi ons, which both contribute to the emergence of new potentially zoonotic viruses. (Source: Veterinary Research)
Source: Veterinary Research - October 7, 2019 Category: Veterinary Research Source Type: research

HutZ is required for biofilm formation and contributes to the pathogenicity of Edwardsiella piscicida
This study is the first functional characterization of HutZ in a fish pathogen, and these findings suggested that HutZEp is essential forE. piscicida biofilm formation and contributes to host infection. (Source: Veterinary Research)
Source: Veterinary Research - October 2, 2019 Category: Veterinary Research Source Type: research

Lactoferrin translocates to the nucleus of bovine rectal epithelial cells in the presence of Escherichia coli O157:H7
AbstractEnterohemorrhagicEscherichia coli (EHEC) O157:H7 is a foodborne pathogen which causes illness in humans. Ruminants are the main reservoirs and EHEC predominantly colonizes the epithelium of the recto-anal junction of cattle. Immunosuppression by EHEC promotes re-infection of cattle. However, bovine lactoferrin (bLF) apparently can overrule the immunosuppression by inducing EHEC-specific IgA responses at the mucosal site. The IgA responses are significantly correlated with reduced EHEC shedding and the absence of colonization at the rectal mucosa following re-infection. Therefore, to examine the interaction between ...
Source: Veterinary Research - October 1, 2019 Category: Veterinary Research Source Type: research

Assessing biases in phylodynamic inferences in the presence of super-spreaders
AbstractPhylodynamic analyses using pathogen genetic data have become popular for making epidemiological inferences. However, many methods assume that the underlying host population follows homogenous mixing patterns. Nevertheless, in real disease outbreaks, a small number of individuals infect a disproportionately large number of others (super-spreaders). Our objective was to quantify the degree of bias in estimating the epidemic starting date in the presence of super-spreaders using different sample selection strategies. We simulated 100 epidemics of a hypothetical pathogen (fast evolving foot and mouth disease virus-lik...
Source: Veterinary Research - September 27, 2019 Category: Veterinary Research Source Type: research

In vivo passage of Salmonella Typhimurium results in minor mutations in the bacterial genome and increases in vitro invasiveness
AbstractEggs and raw or undercooked egg-containing food items are frequently identified as the bacterial source during epidemiolocal investigation ofSalmonella outbreaks. Multi-locus variable number of tandem repeats analysis (MLVA) is a widely usedSalmonella typing method enabling the study of diversity within populations of the same serotype. In vivo passage, however, has been linked with changes in MLVA type and more broadly theSalmonella genome. We sought to investigate whether in vivo passage through layer hens had an effect on MLVA type as well as the bacterial genome and whether any mutations affected bacterial viru...
Source: Veterinary Research - September 24, 2019 Category: Veterinary Research Source Type: research

Early Neospora caninum infection dynamics in cattle after inoculation at mid-gestation with high (Nc-Spain7)- or low (Nc-Spain1H)-virulence isolates
AbstractEarlyNeospora caninum infection dynamics were investigated in pregnant heifers intravenously inoculated with PBS (G-Control) or 107 tachyzoites of high (G-NcSpain7)- or low (G-NcSpain1H)-virulence isolates at 110  days of gestation. Serial culling at 10 and 20 days post-infection (dpi) was performed. Fever was detected at 1 dpi in both infected groups (P 
Source: Veterinary Research - September 24, 2019 Category: Veterinary Research Source Type: research

Spatial and seasonal patterns of FMD primary outbreaks in cattle in Zimbabwe between 1931 and 2016
This study investigated FMD primary outbreak data in Zimbabwe from 1931 to 2016 to describe the spatio-temporal distribution of FMD outbreaks and their potential drivers. The results suggest that: (i) FMD outbreaks were not randomly distributed in space across Zimbabwe but are clustered in the Southeast Lowveld (SEL); (ii) the proximity of protected areas with African buffalos was potentially responsible for primary FMD outbreaks in cattle; (iii) rainfall per se was not associated with FMD outbreaks, but seasons impacted the temporal occurrence of FMD outbreaks across regions; (iv) the frequency of FMD outbreaks increased ...
Source: Veterinary Research - September 24, 2019 Category: Veterinary Research Source Type: research

Haemophilus parasuis VtaA2 is involved in adhesion to extracellular proteins
AbstractHaemophilus parasuis is part of the microbiota of the upper respiratory tract in swine. However, virulent strains can cause a systemic disease known as Gl ässer’s disease. Several virulence factors have been described inH. parasuis including the virulence-associated trimeric autotransporters (VtaAs). VtaA2 is up-regulated during infection and is only found in virulent strains. In order to determine its biological function, thevtaA2 gene was cloned with its native promotor region in pACYC184, and the transformedEscherichia coli was used to perform functional in vitro assays. VtaA2 was found to have a role...
Source: Veterinary Research - September 23, 2019 Category: Veterinary Research Source Type: research

Label-free quantitative proteomic analysis of molting-related proteins of Trichinella spiralis intestinal infective larvae
AbstractMolting is a key step for body-size expansion and environmental adaptation of parasitic nematodes, and it is extremely important forTrichinella spiralis growth and development, but the molting mechanism is not fully understood. In this work, label-free LC –MS/MS was used to determine the proteome differences betweenT. spiralis muscle larvae (ML) at the encapsulated stage and intestinal infective larvae (IIL) at the molting stage. The results showed that a total of 2885T. spiralis proteins were identified, 323 of which were differentially expressed. These proteins were involved in cuticle structural elements, ...
Source: Veterinary Research - September 23, 2019 Category: Veterinary Research Source Type: research

Effects of challenge dose and inoculation route of the virulent Neospora caninum Nc-Spain7 isolate in pregnant cattle at mid-gestation
AbstractParameters such as pathogen dose and inoculation route are paramount in animal models when studying disease pathogenesis. Here, clinical findings, including foetal mortality, parasite transmission rates and lesion severity, and immune responses were evaluated in Asturiana pregnant heifers at day 110 of gestation challenged with a virulent (Nc-Spain7)Neospora caninum isolate. Four different doses of parasite tachyzoites were inoculated intravenously (IV1, 107 parasites,n = 6; IV2, 105,n = 6; IV3, 103,n = 6; and IV4, 102,n = 5), and the subcutaneous (SC) inocula...
Source: Veterinary Research - September 23, 2019 Category: Veterinary Research Source Type: research

Diverse effects of nitric oxide reductase NorV on Aeromonas hydrophila virulence-associated traits under aerobic and anaerobic conditions
This study provides insights into an unexplored area of NorV, which will contribute to our understanding of bacterial pathogenesis and the development of new control strategies forA. hydrophila infection. (Source: Veterinary Research)
Source: Veterinary Research - September 23, 2019 Category: Veterinary Research Source Type: research

The potential of acetylsalicylic acid and vitamin E in modulating inflammatory cascades in chickens under lipopolysaccharide -induced inflammation
AbstractDistinct enzymes, including cyclooxygenase 1 and 2 (COX-1 and COX-2), lipoxygenase (LOXs), and cytochrome P450 monooxygenase (CYP450), produce different stress mediators and mediate inflammation in birds. Bioactive agents such as acetylsalicylic acid (ASA) and vitamin E (vE) may affect enzyme activities and could be used in poultry production to control the magnitude of acute phase inflammation. Here, we characterized COX, LOX, and CYP450 mRNA expression levels in chicken immune tissues in response toEscherichia coli lipopolysaccharide (LPS) challenge and investigated whether ASA and vE could alter gene expression....
Source: Veterinary Research - September 18, 2019 Category: Veterinary Research Source Type: research

The immunomodulatory functions and molecular mechanism of a new bursal heptapeptide (BP7) in immune responses and immature B cells
AbstractThe bursa of Fabricius (BF) is the acknowledged central humoural immune organ unique to birds and plays a vital role in B lymphocyte development. In addition, the unique molecular immune features of bursal-derived biological peptides involved in B cell development are rarely reported. In this paper, a novel bursal heptapeptide (BP7) with the sequence GGCDGAA was isolated from the BF and was shown to enhance the monoclonal antibody production of a hybridoma. A mouse immunization experiment showed that mice immunized with an AIV antigen and BP7 produced strong antibody responses and cell-mediated immune responses. Ad...
Source: Veterinary Research - September 18, 2019 Category: Veterinary Research Source Type: research

Peripheral and placental immune responses in sheep after experimental infection with Toxoplasma gondii at the three terms of gestation
AbstractAlthough it is known that gestation could influence the clinical course of ovine toxoplasmosis, the precise effect of the term of gestation when sheep are infected are yet mostly unknown. The aim of this study was to evaluate the peripheral and placental immune responses developed in pregnant sheep after experimental infection withToxoplasma gondii at different times of gestation. Thirty-six pregnant sheep were allocated in different groups, orally inoculated with sporulated oocysts ofT. gondii at early, mid and late gestation and culled within 30  days post-infection. The peripheral humoral and cytokine respo...
Source: Veterinary Research - September 18, 2019 Category: Veterinary Research Source Type: research

Assessing exhibition swine as potential disseminators of infectious disease through the detection of five respiratory pathogens at agricultural exhibitions
AbstractWidespread geographic movement and extensive comingling of exhibition swine facilitates the spread and transmission of infectious pathogens. Nasal samples were collected from 2862 pigs at 102 exhibitions and tested for five pathogens. At least one pathogen was molecularly detected in pigs at 63 (61.8%) exhibitions. Influenza A virus was most prevalent and was detected in 498 (17.4%) samples. Influenza D virus was detected in two (0.07%) samples. More than one pathogen was detected in 165 (5.8%) samples. Influenza A virus remains a top threat to animal and human health, but other pathogens may be disseminated throug...
Source: Veterinary Research - September 18, 2019 Category: Veterinary Research Source Type: research

Correction to: Genomic comparisons of Streptococcus suis serotype 9 strains recovered from diseased pigs in Spain and Canada
In the original publication of this article [1], the author name ‘Pengchen Du’ in author list should be ‘Pengcheng Du’. (Source: Veterinary Research)
Source: Veterinary Research - September 16, 2019 Category: Veterinary Research Source Type: research

Xanthohumol inhibits PRRSV proliferation and alleviates oxidative stress induced by PRRSV via the Nrf2 –HMOX1 axis
In this study, we first screened a library of 386 natural products and found that xanthohumol (Xn), a prenylated flavonoid found in hops, displayed high anti-PRRSV activity by inhibiting PRRSV adsorption onto and internalization into cells. Transcriptome sequencing revealed that Xn treatment stimulates genes associated with the antioxidant response in the nuclear factor-erythroid 2-related factor 2 (Nrf2) signalling pathway. Xn causes increased expression of Nrf2, HMOX1, GCLC, GCLM, and NQO1 in Marc-145 cells. The action of Xn against PRRSV proliferation depends on Nrf2 in Marc-145 cells and porcine alveolar macrophages (P...
Source: Veterinary Research - September 11, 2019 Category: Veterinary Research Source Type: research

Quantifying transmission of Mycobacterium avium subsp. paratuberculosis among group-housed dairy calves
AbstractJohne ’s disease (JD) is a chronic enteritis caused byMycobacterium avium subsp.paratuberculosis (MAP), with control primarily aimed at preventing new infections among calves. The aim of the current study was to quantify calf-to-calf transmission of MAP among penmates in an experimental trial. Newborn Holstein bull calves (n = 32) were allocated into pens of 4, with 2 inoculated (IN) calves and 2 calves that were contact exposed (CE). Calves were group-housed for 3 months, with frequent collection of fecal and blood samples and tissue collection after euthanasia. The basic reproduction rati...
Source: Veterinary Research - August 20, 2019 Category: Veterinary Research Source Type: research

Variation in the prion protein gene ( PRNP ) sequence of wild deer in Great Britain and mainland Europe
AbstractSusceptibility to prion diseases is largely determined by the sequence of the prion protein gene (PRNP), which encodes the prion protein (PrP). The recent emergence of chronic wasting disease (CWD) in Europe has highlighted the need to investigatePRNP gene diversity in European deer species, to better predict their susceptibility to CWD. Here we report a large genetic survey of six British deer species, including red (Cervus elaphus), sika (Cervus nippon), roe (Capreolus capreolus), fallow (Dama dama), muntjac (Muntiacus reevesii), and Chinese water deer (Hydropotes inermis), which establishesPRNP haplotype and gen...
Source: Veterinary Research - July 31, 2019 Category: Veterinary Research Source Type: research

From hatch to egg grading: monitoring of Salmonella shedding in free-range egg production systems
In this study, two free-range flocks were sampled from hatch to the end of production. At hatch, all chicks wereSalmonella negative and remained negative during rearing. During production, the proportion of positive samples was low on both farms.Salmonella positive samples were detected intermittently for Flock A. Dust, nest box, and egg belt swabs had the highest proportion of positive samples and highest overall loads ofSalmonella. The egg grading floor was swabbed at different points following the processing of eggs from Flock A. Only the suction cups that handle eggs prior to egg washing tested positive forSalmonella. ...
Source: Veterinary Research - July 30, 2019 Category: Veterinary Research Source Type: research

Evaluation of mouse enteroids as a model for Lawsonia intracellularis infection
AbstractLawsonia intracellularis, an obligate intracellular bacterium, is an important enteric pathogen in pig herds and horse farms worldwide. The hallmark feature ofL. intracellularis infection is the proliferation of epithelial cells in intestinal crypts. A major limitation to the study ofL. intracellularis infection is the lack of an in vitro model that reproduces the changes observed in proliferative enteropathy. Here we investigated the suitability of mouse enteroids as a model to studyL. intracellularis infection. Mouse enteroids were microinjected withL. intracellularis, filter-sterilizedL. intracellularis culture ...
Source: Veterinary Research - July 19, 2019 Category: Veterinary Research Source Type: research

Tn-sequencing of Mycoplasma hyopneumoniae and Mycoplasma hyorhinis mutant libraries reveals non-essential genes of porcine mycoplasmas differing in pathogenicity
AbstractMycoplasma hyopneumoniae andMycoplasma hyorhinis are two phylogenetically related species colonizing the respiratory tract of pigs but differing in pathogenicity, the basis of which is not well resolved. We hypothesize that genes belonging to the species-specific portion of the genome and being non-essential during ideal laboratory growth conditions encode possible virulent determinants and are the driver of interspecies differences. To investigate this, transposon mutant libraries were generated for both species and a transposon sequencing (Tn-seq) method for mycoplasmas was established to identify non-essential g...
Source: Veterinary Research - July 19, 2019 Category: Veterinary Research Source Type: research

Intraepithelial neutrophils in mammary, urinary and gall bladder infections
AbstractNeutrophil mobilization is a crucial response to protect the host against invading microorganisms. Neutrophil recruitment and removal have to be tightly regulated to prevent uncontrolled inflammation and excessive release of their toxic content causing tissue damage and subsequent organ dysfunctions. We show here the presence of live and apoptotic neutrophils in the cytoplasm of inflamed mammary, urinary and gall bladder epithelial cells following infection withE. coli and Salmonella bacteria. The entry process commenced with adherence of transmigrated neutrophils to the apical membrane of inflamed epithelial cells...
Source: Veterinary Research - July 19, 2019 Category: Veterinary Research Source Type: research

Modulation of posterior intestinal mucosal proteome in rainbow trout ( Oncorhynchus mykiss ) after Yersinia ruckeri infection
This study showed thatY. ruckeri infection can alter protein abundance involved in serine-type carboxypeptidase, cysteine and aspartic-type endopeptidases, metallopeptidases, antioxidant defense, calcium ion binding, glycolytic and carbohydrate metabolic processes in the proteome of the intestinal mucosa of rainbow trout. (Source: Veterinary Research)
Source: Veterinary Research - July 17, 2019 Category: Veterinary Research Source Type: research

Matrine inhibits IL-1 β secretion in primary porcine alveolar macrophages through the MyD88/NF-κB pathway and NLRP3 inflammasome
In this study, we investigated the anti-IL-1β mechanism of matrine, as IL-1β is a major inflammatory cytokine, in p orcine alveolar macrophages (PAMs) stimulated with 4 μg PRRSV 5′-untranslated region (UTR) RNA and 1 μg/mL LPS. After 5′UTR RNA and LPS co-stimulation of PAMs for 12 h, the expression of IL-1β, IL-6, IL-8 and TNF-α was significantly increased. The results also showed that co-stimulation i nduced the expression of MyD88, and activated the NF-κB signalling pathway and NLRP3 inflammasome. Furthermore, matrine treatment downregulated MyD88, NLRP3 and cas...
Source: Veterinary Research - July 12, 2019 Category: Veterinary Research Source Type: research

Interleukin-1 signaling induced by Streptococcus suis serotype 2 is strain-dependent and contributes to bacterial clearance and inflammation during systemic disease in a mouse model of infection
AbstractStreptococcus suis serotype 2 is an important porcine pathogen and zoonotic agent causing sudden death, septic shock and meningitis, with exacerbated inflammation being a hallmark of the infection. A rapid, effective and balanced innate immune response againstS. suis is critical to control bacterial growth without causing excessive inflammation. Even though interleukin (IL)-1 is one of the most potent and earliest pro-inflammatory mediators produced, its role in theS. suis pathogenesis has not been studied. We demonstrated that a classical virulent European sequence type (ST) 1 strain and the highly virulent ST7 st...
Source: Veterinary Research - July 1, 2019 Category: Veterinary Research Source Type: research

Mycoplasma hyopneumoniae evades phagocytic uptake by porcine alveolar macrophages in vitro
AbstractMycoplasma hyopneumoniae, the agent of porcine enzootic pneumonia (EP), is able to persist in the lung tissue and evade destruction by the host for several weeks. To understand the mechanism of pathogen survival, phagocytic uptake ofM. hyopneumoniae by primary porcine alveolar macrophages was investigated. Intracellular location and survival of the pathogen were explored using gentamicin survival assays, flow cytometry and confocal microscopy ofM. hyopneumoniae 232 labelled with green fluorescent protein (GFP). Following 1  h and 16 h of co-incubation, few viableM. hyopneumoniae were recovered from inside...
Source: Veterinary Research - June 24, 2019 Category: Veterinary Research Source Type: research

Amino acidic substitutions in the polymerase N-terminal region of a reassortant betanodavirus strain causing poor adaptation to temperature increase
AbstractNervous necrosis virus (NNV), GenusBetanodavirus, is the causative agent of viral encephalopathy and retinopathy (VER), a neuropathological disease that causes fish mortalities worldwide. The NNV genome is composed of two single-stranded RNA molecules, RNA1 and RNA2, encoding the RNA polymerase and the coat protein, respectively. Betanodaviruses are classified into four genotypes: red-spotted grouper nervous necrosis virus (RGNNV), striped jack nervous necrosis virus (SJNNV), barfin flounder nervous necrosis virus (BFNNV) and tiger puffer nervous necrosis virus (TPNNV). In Southern Europe the presence of RGNNV, SJN...
Source: Veterinary Research - June 21, 2019 Category: Veterinary Research Source Type: research

Toll-like receptor 5-mediated IL-17C expression in intestinal epithelial cells enhances epithelial host defense against F4 + ETEC infection
In this study, we demonstrate that F4+ ETEC induce IL-17C mRNA and protein expression in intestinal tissues as well as in porcine intestinal epithelial cells (IPEC-J2). This IL-17C production is largely dependent on TLR5 signaling in IPEC-J2 cells. Both F4+ ETEC infection and exogenous IL-17C increased the expression of antimicrobial peptides and tight junction proteins, such as porcine beta-defensin (pBD)-2, claudin-1, claudin-2 and occludin in IPEC-J2 cells. Taken together, our data demonstrate that TLR5-mediated IL-17C expression in intestinal epithelial cells enhances mucosal host defense responses in a unique autocrin...
Source: Veterinary Research - June 20, 2019 Category: Veterinary Research Source Type: research

Evaluation of a Rhodomyrtus tomentosa ethanolic extract for its therapeutic potential on Staphylococcus aureus infections using in vitro and in vivo models of mastitis
AbstractAn ethanolic extract fromRhodomyrtus tomentosa leaves (RTL) was studied as a natural alternative to controlStaphylococcus aureus, which is an important pathogen responsible for bovine mastitis. The minimal inhibitory concentrations (MICs) of the RTL extract and of rhodomyrtone, a pure compound isolated from the plant, were determined by a microdilution method. Rhodomyrtone and the RTL extract exhibited antibacterial activity againstS. aureus, including its persistent phenotype (SCV: small-colony variant) and a biofilm hyperproducer strain, with MICs of 0.25 –0.5 and 8–16 µg/mL, respectively. ...
Source: Veterinary Research - June 20, 2019 Category: Veterinary Research Source Type: research

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 19, 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 18, 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 18, 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 6, 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 4, 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 4, 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 3, 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 24, 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 24, 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 22, 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 22, 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 22, 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 16, 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 14, 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 14, 2019 Category: Veterinary Research Source Type: research