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Viral haemorrhagic septicaemia ( VHS) is a notifiable fish disease, whose causative agent is a rhabdovirus isolated from a wide range of fish species, not only in fresh but also in marine and brackish waters. Phylogenetic studies have identified four major genotypes, with a strong geographical relationship. In this study, we have designed and validated a new procedure - named binary multiplex RT- qPCR (bm RT- qPCR) - for simultaneous detection and typing of all four genotypes of VHSV by real-time RT- PCR based on dual-labelled probes and composed by two multiplex systems designed for European and American/Asiatic isolates, respectively, using a combination of three different fluorophores. The specificity of the procedure was assessed by including a panel of 81 VHSV isolates covering all known genotypes and subtypes of the virus, and tissue material from experimentally infected rainbow trout, resulting in a correct detection and typing of all strains. The analytical sensitivity was evaluated in a comparative assay with titration in cell culture, observing that both methods provided similar limits of detection. The proposed method can be a powerful tool for epidemiological analysis of VHSV by genotyping unknown samples within a few hours. [ABSTRACT FROM AUTHOR]

Viral haemorrhagic septicaemia (VHS) is an infectious disease of farmed and wild fish and has an extensive host range in both freshwater and marine environments. In December 2012, a wrasse population consisting of ballan, Labrus bergylta (Ascanius), corkwing, Symphodus melops (L.), cuckoo, Labrus mixtus L., goldsinny, Ctenolabrus rupestris (L.), and rock cook, Centrolabrus exoletus (L.), held at a marine hatchery in the Shetland Isles, Scotland, experienced a mortality event. Approximately 10 000 wrasse were being held at the facility on behalf of an Atlantic salmon, Salmo salar L., aquaculture company prior to being deployed for the biological control of parasites on marine pen Atlantic salmon, aquaculture sites. Fish Health Inspectors from Marine Scotland Science initiated a diagnostic investigation, and subsequent diagnostic testing confirmed the site to be VHSV positive by q RT-PCR and virus isolation followed by ELISA. A VHSV genotype-specific q RT-PCR assay revealed that the isolates belonged to genotype III, the European marine strain of the virus. The virus genotype was further confirmed by nucleic acid sequencing of the partial nucleoprotein (N) and glycoprotein (G) genes followed by BLAST nucleotide searches. This study reports for the first time the detection of VHSV within multiple wrasse species and highlights the need for a comprehensive risk-based approach to the use of wrasse and other finfish species as biological controls within the aquaculture industry. [ABSTRACT FROM AUTHOR]

Viral haemorrhagic septicaemia ( VHS), caused by the novirhabdovirus viral haemorrhagic septicaemia virus ( VHSV), causes significant economic problems to European rainbow trout, Oncorhynchus mykiss ( Walbaum), production. The virus isolates can be divided into four distinct genotypes with additional subgroups. The main source of outbreaks in European rainbow trout farming is sublineage Ia isolates. Recently, this group of isolates has been further subdivided in to two subclades of which the Ia-2 consists of isolates occurring mainly in Continental Europe outside of Denmark. In this study, we sequenced the full-length G-gene sequences of 24 VHSV isolates that caused VHS outbreaks in Polish trout farms between 2005 and 2009. All these isolates were identified as genotype Ia-2; they divided however into two genetically distinct subgroups, that we name Pol I and Pol II. The Pol I isolates mainly caused outbreaks in the southern part of Poland, while Pol II isolates predominantly were sampled in the north of Poland, although it seems that they have been transmitted to other parts of the country. Molecular epidemiology was used for characterization of transmission pathways. This study shows that a main cause of virus transmission appears to be movement of fish. At least in Polish circumstances trading practices appear to have significant impact on spreading of VHSV infection. [ABSTRACT FROM AUTHOR]

Two experiments were performed to determine the persistence of viral hemorrhagic septicemia virus (VHSV) genotype IVb on WalleyeSander vitreuseggs. Fertilized Walleye eggs were exposed for 30 min to 105plaque-forming units/mL VHSV genotype IVb, and control eggs were exposed to phosphate-buffered saline. In the first experiment, the eggs were treated with 0 and 50 mg/L iodophor and incubated at 12±1°C until the first fry emerged. In the second experiment, a treatment of 100 mg/L iodophor was also tested. Periodic samples were taken during embryo development and tested for VHSV by viral isolation and quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The effect of tannic acid, an inhibitor of qRT-PCR testing, was evaluated in the second experiment. In both experiments no virus was detected in any control eggs by either test. In the first experiment, virus was isolated in 0-mg/L iodophor-treated eggs up to 3 d postinfection (DPI). Virus was also isolated in the 50-mg/L iodophor-treated group at 1 DPI. Testing by qRT-PCR detected viral RNA at all time points throughout the first experiment. In the second experiment, no VHSV was isolated after the initial 0-DPI sample. Viral RNA was again detected at all time points, including samples collected at the end of the experiment. Inhibition was found in 34 of 36 samples at 0 DPI and 21 of 36 samples at 1 DPI. The number of inhibited samples decreased over time, but virus was still detected in three samples at 24 DPI. These experiments show that VHSV persists on Walleye eggs for longer than was previously known. At early time points VHSV was still detected despite disinfection, and viral RNA was detected at all time points; however, it is unknown whether the virus detected by this qRT-PCR is viable. These experiments reinforce the need for careful disinfection of eggs. Received November 28, 2011; accepted February 26, 2012 [ABSTRACT FROM PUBLISHER]

The article discusses the development of DNA vaccine for the treatment of viral haemorrhagic septicaemia virus (VHSV) and infectious haematopoietic necrosis virus (IHNV). It says that Oncorhynchus mykiss was vaccinated with one μg of either viral haemorrhagic septicaemia (VHS) or IHN vaccine. It mentions that subsamples of fish were removed from each holding tank to determine the relative protection of the treatments against VHS.

The efficacy of an intranasal haemorrhagic septicaemia vaccine containing live gdhA derivative Pasteurella multocida B:2 was tested in buffaloes in Sabah. Sixty buffaloes, kept grazing in the field with minimal human intervention were devided into three groups of buffaloes per group. Buffaloes of group 1 were exposed intranasal to 5 ml vaccine containing 106 CFU/ml of live gdhA derivative P multocida B:2. Buffaloes of group 2 were not exposed to the vaccine but exposed to PBS and were allowed to commingle and graze in the same field as the buffaloes of group 1 while buffaloes of group 3 were similarly exposed to PBS and were grazing separately. Booster was on group 1, two weeks later. Twelve months after the first vaccination, three buffaloes from each group were brought into the experimental house and challenged subcutaneously with 109 CFU/ml of live wild-type P multocida B:2. All challenged buffaloes of groups 1 and 2 survived with only mild, transient signs while all control unvaccinated buffaloes developed severe signs of haemorrhagic septicaemia and were euthanased between 28 hours and 38 hours postchallenge with signs and lesions typical of haemorrhagic septicaemia. These data showed that the gdhA mutant strain, given intranasally as two doses two weeks apart, successfully induced systemic immunity in exposed buffaloes and also led to spread of vaccine strain to the in-contact animals, where it acted as an effective live vaccine to protect both exposed buffaloes and in-contact buffaloes against challenge with the virulent parent strain. [ABSTRACT FROM AUTHOR]

ABSTRACT Background and aim: Pasteurella multocida B:2, which causes hemorrhagic septicemia of ruminants, is believed to enter the host via respiratory and oral routes. While the role of respiratory route of infection has been established, the present study describes the clinical and pathological alterations following oral exposure of buffalo calves to live wild-type Pasteurella multocida B:2. Methods: Nine 8-month-old buffalo calves were selected and divided into three groups. Calves of group 1 were exposed orally to 50 mL of the inoculums containing 109 colony-forming unit (CFU)/mL of live Pasteurella multocida B:2. Calves of group 2 were exposed intra-tracheal to 5 mL of the same inoculums while calves of group 3 were exposed orally to 50 mL of phosphate-buffered saline. Results: Only one calf had to be euthanized at 48 h post-intra-tracheal exposure due to persistent clinical signs of hemorrhagic septicemia. The mean respiratory rate and rectal temperature had significantly increased in calves of groups 1 and 2. The pathological alterations included submandibular and brisket edema, generalized lymphadenopathy, acute fibrinous pneumonia, acute colitis and hemorrhagic typhilitis and proctitis. Nevertheless, oral infection with 109 CFU/mL of live wild-type P. multocida B:2 failed to produce a typical clinical disease. However, P. multocida B:2 was present along the gastro-intestinal tract, including the rectum of the calf that succumbed to the infection at 48 h post-intra-tracheal exposure. Conclusions: The presence of P. multocida B:2 along the gastro-intestinal tract is of concern since transmission via the gastro-intestinal tract of diseased animals is strongly possible. [ABSTRACT FROM AUTHOR]

Vibrio anguillarum, also known as Listonella anguillarum, is the causative agent of vibriosis, a deadly haemorrhagic septicaemic disease affecting various marine and fresh/brackish water fish, bivalves and crustaceans. In both aquaculture and larviculture, this disease is responsible for severe economic losses worldwide. Because of its high morbidity and mortality rates, substantial research has been carried out to elucidate the virulence mechanisms of this pathogen and to develop rapid detection techniques and effective disease-prevention strategies. This review summarizes the current state of knowledge pertaining to V. anguillarum, focusing on pathogenesis, known virulence factors, diagnosis, prevention and treatment. [ABSTRACT FROM AUTHOR]

Surface de-adhesion and disinfection of eggs at hatcheries are critical steps in successful fry culture; however, little is known about the effects of the combination of these compounds on the efficacy of egg surface disinfection. We examined the effect of tannic acid on detection of viral hemorrhagic septicemia virus (VHSV) type IVb alone and in the presence of iodophor under in vitro conditions. We confirmed that tannic acid inhibits the quantitative reverse-transcriptase polymerase chain reaction assay developed in our laboratory and that it binds to VHSV, reversibly decreasing infectivity. Surprisingly, we also found that when combined with iodophor, tannic acid destroys the ability of either compound to inhibit infectivity. While we still strongly encourage the use of iodophor for its antiviral, bactericidal, and fungicidal properties, our results suggest that when tannic acid is used prior to disinfection with iodophor, it must be very thoroughly rinsed to ensure that it does not interfere with the disinfectant properties of iodophor. [ABSTRACT FROM AUTHOR]

The article highlights issues discussed in the disease surveillance report for October 2007 from the Scottish Agricultural College Veterinary Services (SAC VS). These include outbreaks of systemic pasteurellosis recorded in sheep, polydactyly in newborn Belgian blue cross Holstein calves, incidence of fasciolosis in cattle, and haemonchosis diagnosed in four Dumfriesshire flocks.

Haemorrhagic septicaemia (HS) is an acute disease of cattle and buffaloes caused by Pasteurella multocida 6:B. Outbreaks of the disease have been closely associated with carrier animals that transmit the organism to susceptible animals during stressful condition. This study was conducted to determine whether goats exposed intranasally to P. multocida 6:B can transmit the organism to contact goats. Thirty-six healthy local Katjang goats were divided into four groups and goats of groups 1 and 3 were each inoculated intranasally with a 1-ml inoculum that contained 1 × 109 CFU/ml of live P. multocida 6:B. Following the exposure, all goats of groups 3 and 4 were injected with dexamethasone at the rate of 1 mg/kg for three consecutive days. At the end of the dexamethasone treatment, goats of groups 1 and 2 were commingled but kept separate from goats of groups 3 and 4, which were commingled in another pen. Three surviving goats from each group were killed on days 7, 14 and 21 post-exposure for postmortem examination. Naso-pharyngeal mucus and heart blood were collected on swabs. Tissues from lungs, lymph nodes and tonsils were collected for bacteriological isolation and identification. Only one goat of group 3 died 6 days post-exposure showing clinical signs and lesions typical of HS. Other goats showed mild signs of upper respiratory tract infection. Goats of all groups developed acute mild pneumonic lesions, however, those treated with dexamethasone had significantly ( P < 0.05) more extensive lesion scoring based on the lesion scoring system. P. multocida 6:B was isolated from the nasal mucosa and lung lesions of exposed and contact goats not treated with dexamethasone. Exposed and contact goats treated with dexamethasone carried the organism for 21 days. P. multocida isolation from heart blood was made only from exposed and contact goats treated with dexamethasone. P. multocida was isolated from the lymph node of the goat that died during the experiment. [ABSTRACT FROM AUTHOR]

Information about the topics discussed during the Scottish Animal Health and Welfare conference held on November 29-30, 2006 in Pitlochry, Scotland is presented. Increase in the number of cases of pasteurellosis in sheep, seasonal rise in cases of Salmonella in cattle, and infectious bovine rhinotracheitis the most common cause of bovine pneumonia, are among the topics discussed in the conference.

Vibrio anguillarum, part of the normal flora of the aquatic milieu, causes a fatal haemorrhagic septicaemia in marine fish. In this study, a rainbow trout model was used to characterize the colonization of fish skin by V. anguillarum. Within 5 h after infection, the bacterium penetrated the skin mucosal layer, attached to the scales within 12 h, and formed a biofilm by 24–48 h. Two divergently transcribed putative operons, orf1-wbfD-wbfC-wbfB and wza-wzb-wzc, were shown to play a role in skin colonization and virulence. The first operon encodes proteins of unknown function. The wza-wzb-wzc genes encode a secretin, tyrosine kinase and tyrosine phosphatase, respectively, which are similar to proteins in polysaccharide transport complexes. Compared with the wild type, polar mutations in wza, orf1 and wbfD caused a decrease in exopolysaccharide biosynthesis but not lipopolysaccharide biosynthesis. The wza and orf1 mutants did not attach to fish scales; whereas, the wbfD mutant had a wild-type phenotype. Moreover, the wza and orf1 mutants had decreased exoprotease activity, in particular the extracellular metalloprotease EmpA, as well as mucinase activity suggesting that these mutations also affect exoenzyme secretion. Thus, the exopolysaccharide transport system in V. anguillarum is required for attachment to fish skin, possibly preventing mechanical removal of bacteria via natural sloughing of mucus. [ABSTRACT FROM AUTHOR]

A survey based on clinical, pathological and microbiological investigations was performed on 11 Brown Swiss cattle affected with depression, anorexia, agalaxia, ruminal hypomotility, abdominal pain and melaena. In eight animals, macroscopical lesions consisted in haemorrhagic enteritis in the small intestine. Seven of eight isolates from tissue samples were identified as Clostridum perfringens type A, and four were identified as C. perfringens type A with the β2 toxin gene. Based on these observations, animals were considered affected with haemorrhagic bowel syndrome. [ABSTRACT FROM AUTHOR]

The safety, efficacy and cross-protectivity of a live intranasal aerosol haemorrhagic septicaemia vaccine containing Pasteurella multocida serotype B:3,4 were tested in young cattle and buffaloes in Myanmar, where more than 15 million animals had been inoculated with this vaccine between 1989 and 1999. A recommended dose of 2 × 107 viable organisms was used for the efficacy test. The administration of 100 times the recommended dose to 50 cattle and 39 buffalo calves was innocuous. Seven months after they were vaccinated, three of three buffaloes were protected and 12 months after they were vaccinated, three of four buffaloes were protected against a subcutaneous challenge with serotype B:2 which killed three of three unvaccinated buffaloes. Twelve months after they were vaccinated, eight of eight cattle survived a serotype B:2 challenge, which killed four of four unvaccinated controls. The vaccinated cattle had developed serum antibodies detectable by the passive mouse protection test. Indirect haemagglutination tests on sera taken from cattle 10 days and five weeks after they were vaccinated showed high titres of antibodies. The serum of vaccinated cattle cross-protected passively immunised mice against infection with P multocida serotypes E:2, F:3,4 and A:3,4. [ABSTRACT FROM AUTHOR]

The biochemical properties and antibiotic sensitivity patterns of 13 Pasteurella piscicida isolates from Greece are described and compared with 10 Japanese and five European (Italian and French) isolates. Morphologically and biochemically, all isolates of P. piscicida tested were nearly identical and only minor differences could be detected with reference to the level of acid production from sugars (especially from glucose). Greek, Italian and French isolates showed similar antibiotic sensitivity patterns, being resistant to erythromycin, kanamycin and streptomycin, and sensitive to most of the other antibiotics tested. Resistance was also demonstrated for some isolates towards the potentiated sulphonamides. The Japanese isolates appeared to be resistant to a larger range of antibiotics including erythromycin, kanamycin, streptomycin, oxolinic acid, oxytetracycline and chloramphenicol. Multiple resistance of Japanese strains was also noted. These results are discussed in the light of future measures for the control of pasteurellosis. [ABSTRACT FROM AUTHOR]

An epizootic in juvenile turbol reared on a farm located in the Ria de Vigo, Galicia, Northwest Spain, is described. The diseased turbot did not display unusual swimming behaviour; the external signs of the disease were abdominal distension and haemorrhagic in the peritoneal cavity. Microbiological analysis of the diseased fish revealed the presence, in pure culture in all the organs and lesions examined, of a bacterium which was characterized biochemically as Vibrio splendidus biotype 1. The virulence tests showed that the V. splendidus biotype 1 isolate was pathogenic for rainbow trout (LD50: 2.2 × 104') and also for turbot (LD50: 12 × 104). The treatment of the fish using flumequine incorporated into the feed was effective in offsetting the mortality rate. [ABSTRACT FROM AUTHOR]

The article focuses on seasonal increase in pasteurellosis in lambs in Scotland. The disease surveillance report for September 2006 from Scottish Agricultural College Veterinary Services discussed topics including outbreak of neonatal enteritis in calves due to attaching and effacing Escherichia coli infection.

Mass mortality events in wildlife are a growing concern. Under conditions of rapid global change, opportunistic responses in bacterial commensals, triggered by environmental stressors, may be increasingly implicated in die‐offs. In 2015, over 200,000 saiga antelope died of hemorrhagic septicemia caused by the pathogen Pasteurella multocida serotype B. We use this case to explore die‐offs from commensal bacteria more broadly, looking at factors which might favor such extreme events. We review other recorded disease outbreaks caused by Pasteurellaceae organisms, firstly in saiga and secondly in other wild ungulates, and ask whether the 2015 die‐off was unprecedented in terms of mortality rates, numbers dead, spatial scale, and in the nature of the predisposing or environmental factors involved. We also compare these outbreaks with mass mortality events associated with commensal bacteria in wildlife more generally. We identify three additional major die‐offs in saiga in which Pasteurellaceae organisms may be implicated, of which one in 1988 closely resembles the 2015 hemorrhagic septicemia event. No other recorded cases in wild ungulates approach the magnitude of these cases for any of the metrics considered, possible exceptions being die‐offs in Mongolian gazelles, in which the role of these pathogens is poorly substantiated. Environmental triggers were the most commonly suggested factor leading to pathogenesis, with warm humid conditions most commonly associated with hemorrhagic septicemia. Life history may also be significant—saigas are migratory and the largest pasteurellosis outbreaks outside this species also occur in migratory species of bird or other temperate ungulates aggregating in large numbers. Cases provoked by other commensals tend to be small in magnitude. Exceptions involve interactions between multiple pathogens and climatic conditions or sets of climatic conditions acting on different stages of the host–pathogen life cycle, leading to time lags between infection and subsequent disease. Overall, the scale and rapidity of the saiga die‐offs appear unprecedented among mortality events caused by bacterial commensals in wild mammals. Experimental research into the genetics and microbiology of host–pathogen interactions upon changes in the external environment, and monitoring of animals and conditions at calving sites, may eventually reveal the underlying causes of these die‐offs. [ABSTRACT FROM AUTHOR]

The article reports on the effectiveness of danofloxacin in the treatment of pneumonic pasteurellosis in specific pathogen-free lams. It is demonstrated through injection in order to reduce the lung pathology, bacterial infection and clinical signs of respiratory disease. An overview of its experimental model is offered.

The article discusses the haemorrhagic speticaemia (HS) re-emergence in ungulates in Lower-Saxony, Germany. It mentions that the infectious disease, also known as acute pasteurellosis, is determined through high mortality and morbidity which affects pigs and cattle. It notes its symptoms, such as fibrinous pleuropneumonia, fever and subcutaneous oedema, and its causative agent Pasteurella multocida gram-negative bacteria. It also emphasizes the nature of the HS as a virulent bacterial disease.

The article offers information on the press event of the Moredun Research Institute on December 13, 2011. It says that Moredun had a round up of several researches such as the vaccine for haemorrhagic septicaemia (HS) in cattle and a diagnostic test for liver fluke. It states that Julie Fitzpatrick of Moredun discussed the issue on food security. It also mentions that Moredun Foundation introduced a scholarship scheme for livestock health and welfare projects.

The article discusses the report published within the issue by Kevin Godinho and colleagues on the efficacy of a single dose of danoflaxacin in lambs with pasteurellosis.