scholarly journals Susceptibility of various animals to the vesiculovirus Piry

1984 ◽  
Vol 93 (1) ◽  
pp. 147-155 ◽  
Author(s):  
C. R. Wilks ◽  
J. A. House
Keyword(s):  
Elevated Temperature ◽  
Adult Female ◽  
Specific Antibody ◽  
Clinical Signs ◽  
Neutralizing Antibody ◽  
Domestic Animals ◽  
Post Inoculation ◽  
Pathogenic Potential ◽  
Vesicular Stomatitis ◽  
Chicken Eggs

SUMMARYTo determine the pathogenic potential of the vesiculovirus Piry for domestic animals, two ponies, two steers, three sheep, three goats and three pigs were inoculated intradermally in the tongue or, in the case of the pigs, in the snout, heel and coronary band. Inoculated animals were housed in one room and allowed to mingle freely with an equal number of uninoculated contact animals of each species. Clinical signs of infection, consisting of elevated temperature and ulcers at the inoculation sites, were only observed in the ponies, but all inoculated animals developed specific antibody following inoculation. In addition, one of the contact sheep had neutralizing antibody to Piry at 7 and 29 days post inoculation suggesting a contact infection. Virus was not demonstrated in tissues, other than tongue, of any animal.The failure of Piry virus to produce lesions in steers, sheep, goats and pigs and only limited ulcerations in ponies suggests that this virus is not similar pathogenically to New Jersey and Indiana strains of vesiculoviruses which produce classical vesicular stomatitis.Lethal infections were produced by inoculation into suckling mice and hamsters, adult hamsters and embryonating chicken eggs. Further, lethal infections followed contact of adult female hamsters with their inoculated litters.

scholarly journals Susceptibility of various animals to the vesiculoviruses Isfahan and Chandipura

1986 ◽  
Vol 97 (2) ◽  
pp. 359-368 ◽  
Author(s):  
C. R. Wilks ◽  
J. A. House
Keyword(s):  
Clinical Signs ◽  
Neutralizing Antibody ◽  
Post Inoculation ◽  
Serum Samples ◽  
Pathogenic Potential ◽  
Adult Mice ◽  
Antibody Titres ◽  
The Right ◽  
Chicken Eggs ◽  
Old Mice

SummaryTo determine the pathogenic potential of the vesiculoviruses Isfahan Chandipura for domestic animals, two ponies, two steers, three and three pigs were inoculated with each virus intradermally in the tongue or, in the case of the pigs, in the snout, heel and coronary band The Ponies were also inoculated intradcrmally in the right commissure o the mouth Animals inoculated with each virus were housed in one room and allowed to mingle freely with an equal number of uninoculated contact animals of each species.Clinical signs of infection, consisting of ulcers at the inoculation sites, were observed in the Chandipura study in two inoculated ponies, one inoculated steer and one inoculated goat. No elevated temperature was observed. Virus was isolated from the ulcerated tongue tissue but not from serial blood samples, oesophagcal-pharyngeal mucus samples, or from the tissues which were collected at necropsy. Precipitating antibody was not detected by the immunoelectro osmophoresis(IEOP) test in any of the pre- or post-serum samples except from two inoculated sheep at 29 days post-inoculation (D.P.I.). Low levels of neutralizing activity were dtedted in pre-inoculation serum from all steers, pigs, contact sheep, and one contact goa. By 15 D.P.I. all inoculated animals and contact ponies and steers exhibited increased neutralizing antibody titres.In studies with the Isfahan virus, lesions developed only at the inoculation sites in the two ponies, and the virus was isolated. No virus was isolated from any blood, oesophageal-pharyngeal mucus samples or tisues collected at necropsy. All pre-inoculation sera were negative for neutralizing and precipitating antibodies. By 14 D.P.I. all inoculated animals exhibited neutralizing antibody, while all the contacts remained negative. The IEOP test remained negative for all animals throughout the experiment. A subpassage of a suspension of Isfahan-infected tongue tissue injected in to ponies and steers also yielded only firm swellings of lesser extent than the original reaction at the inoculation sites.With both viruses, lethal infections were produced by intraacranial or intraperitoneal inoculation of day-old mice and hamsters, and by allantoic inoculation of embryonating chicken eggs. Adult mice, hamsters, guinea-pigs and rabbits produced serum antibodies but lacked clinical signs.

scholarly journals Chlamydia gallinacea: genetically armed as a pathogen however a phenotypical commensal?

2020 ◽  
Author(s):  
Marloes Heijne ◽  
Martina Jelocnik ◽  
Alexander Umanets ◽  
Michael S.M. Brouwer ◽  
Annemieke Dinkla ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Clinical Signs ◽  
Chlamydia Psittaci ◽  
Pathogenic Potential ◽  
Animal Pathogens ◽  
The Family ◽  
Chicken Eggs ◽  
Sequence Types ◽  
Embryonated Chicken ◽  
Infection Experiments

AbstractChlamydia gallinacea is an obligate intracellular bacterium that has recently been added to the family of Chlamydiaceae. C. gallinacea is genetically diverse, widespread in poultry and a suspected cause of pneumonia in slaughterhouse workers. In poultry, C. gallinacea infections appear asymptomatic, but studies about the pathogenic potential are limited. In this study two novel sequence types of C. gallinacea were isolated from apparently healthy chickens. Both isolates (NL_G47 and NL_F725) were closely related to each other and showed 99.1% DNA sequence identity to C. gallinacea Type strain 08-1274/3. To gain further insight in the pathogenic potential, infection experiments in embryonated chicken eggs and comparative genomics with Chlamydia psittaci were performed. C. psittaci is an ubiquitous zoonotic pathogen of birds and mammals, and infection in poultry can result in severe systemic illness. In experiments with embryonated chicken eggs C. gallinacea induced mortality was observed, potentially strain dependent but lower compared to C. psittaci induced mortality. Comparative analyses confirmed all currently available C. gallinacea genomes possess the hallmark genes coding for known and potential virulence factors as found in C. psittaci albeit to a reduced number of orthologues or paralogs. The presence of (potential) virulence factors and the observed mortality in embryonated eggs indicates C. gallinacea should rather be considered as a (conditional) pathogen than an innocuous commensal.ImportanceChlamydiaceae are a family of bacteria comprising human and animal pathogens including the recently recognized Chlamydia gallinacea. C. gallinacea is widespread in poultry without causing clinical signs, which raises questions about its pathogenic potential. To assess this potential, two novel C. gallinacea strains were isolated, tested in infection experiments in embryonated chicken eggs and compared to C. psittaci. C. psittaci infection in poultry can result in severe systemic illness, depending on the conditions, and infections can be transmitted to humans. In the experiments C. gallinacea infection induced mortality of the embryo, but to a lower extent than infection with C. psittaci. Subsequent genome comparisons confirmed both C. gallinacea strains possess potential virulence genes typical for chlamydia, but fewer than C. psittaci. These results indicate C. gallinacea does have a pathogenic potential which warrants further research to elucidate its role as a poultry pathogen.

scholarly journals Characterisation of some Ornithobacterium rhinotracheale strains and examination of their transmission via eggs

2001 ◽  
Vol 49 (2) ◽  
pp. 125-130 ◽  
Author(s):  
J. Varga ◽  
L. Fodor ◽  
L. Makrai
Keyword(s):  
Clinical Signs ◽  
Polymyxin B ◽  
Penicillin G ◽  
Post Inoculation ◽  
Biochemical Characteristics ◽  
High Concentrations ◽  
Egg Shell ◽  
Chicken Eggs ◽  
Embryonated Chicken ◽  
Ornithobacterium Rhinotracheale

The biochemical characteristics and antibiotic susceptibility of 12 Ornithobacterium rhinotracheale strains isolated from chickens and turkeys suffering from respiratory clinical signs and the survival of some isolates on egg-shell and within chicken eggs during hatching were examined. All O. rhinotracheale strains showed typical biochemical characteristics. Among the 16 drugs examined, penicillin G, ampicillin (MICs ranging from ≤ 0.06 μg/ml to 1 μg/ml), ceftazidim (with MICs from ≤ 0.06 μg/ml to 0.12 μg/ml), erythromycin, tylosin, tilmicosin (with some exceptions MICs ranged from ≤ 0.06 μg/ml to 1 μg/ml) and tiamulin (MICs varied from ≤ 0.06 μg/ml to 2 μg/ml) were the most effective. Lincomycin, oxytetracycline and enrofloxacin also gave good inhibitions, but with most strains in a higher concentration (MICs ranged in most cases from 2 μg/ml to 8 μg/ml). The other antibiotics inhibited the growth of O. rhinotracheale only in very high concentrations (colistin) or not at all (apramycin, spectinomycin, polymyxin B). At 37 °C, O. rhinotracheale did not survive on egg-shell for more than 24 hours, while upon inoculation into embryonated chicken eggs it killed embryos by the ninth day, and from the 14th day post-inoculation no O. rhinotracheale could be cultured from the eggs at all. These results suggest that O. rhinotracheale is not transmitted via eggs during hatching.

scholarly journals Experimental infection of broiler chicks with Salmonella Typhimurium from pigeon (Columba livia)

2016 ◽  
Vol 37 (4) ◽  
pp. 1919
Author(s):  
Átilla Holanda de Albuquerque ◽  
Régis Siqueira de Castro Teixeira ◽  
Débora Nishi Machado ◽  
Elisângela De Souza Lopes ◽  
Ruben Horn Vasconcelos ◽  
...  
Keyword(s):  
Salmonella Typhimurium ◽  
Clinical Signs ◽  
Columba Livia ◽  
Poultry Feed ◽  
Economic Losses ◽  
Control Group ◽  
Broiler Chicks ◽  
Post Inoculation ◽  
Microbiological Analysis ◽  
Fecal Samples

Several cases of animal and human salmonellosis caused by the Salmonella serotype Typhimurium have been reported. In animals, subclinical infection favors pathogen dissemination through feces. In this context, the domestic pigeon (Columba livia) with an asymptomatic condition may play an important role in the transmission of salmonellosis, through the elimination of contaminated feces in commercial aviaries or in poultry feed facilities, causing economic losses to the poultry industry and presenting a risk to public health. This study aimed to evaluate the mortality, clinical signs and the presence of Salmonella Typhimurium in the feces and organs of chicks previously inoculated with bacteria isolated from a pigeon. One-day-old chicks were distributed in two experimental groups (G1 and G2) of 32 birds each, and a control group of six birds. Two inocula of 0.4 and 0.7 mL with 105 and 106 colony forming units were used in G1 and G2 birds, respectively. At 1, 4, 7 and 14 days post-inoculation (dpi) fecal samples were pooled from each cage and individual cloacal swabs were collected. At 14 dpi, all chicks were euthanized and samples were collected from the liver, spleen, lung, cecum and intestine for microbiological analysis. Mortality was only observed among G2 birds (6.25%). Most birds presented clinical signs of diarrhea at 4 dpi and no symptom as observed at 14 dpi. The results from cloacal swabs demonstrated bacterial elimination in 68.8% and 53.1% of G2 and G1 birds, respectively at 1 dpi. Additionally, fecal samples had elevated bacterial shedding in all four periods of observation , with a higher excretion at 4 dpi (62.5%) for both groups. Among G2 birds, 74.2% were positive for the pathogen in the intestine; G1 birds presented the lowest rate of lung infection (29%), and both groups had more than 50% positivity for liver and caeca. The results revealed that infected chicks with a Salmonella Typhimurium strains isolated from pigeons may host the pathogen in several organs, and simultaneously present diarrheic disorders with significant levels of bacterial excretion in feces.

scholarly journals Vaccination against Canine Distemper Virus Infection in Infant Ferrets with and without Maternal Antibody Protection, Using Recombinant Attenuated Poxvirus Vaccines

2000 ◽  
Vol 74 (14) ◽  
pp. 6358-6367 ◽  
Author(s):  
Janet Welter ◽  
Jill Taylor ◽  
James Tartaglia ◽  
Enzo Paoletti ◽  
Charles B. Stephensen
Keyword(s):  
Canine Distemper Virus ◽  
Clinical Signs ◽  
Neutralizing Antibody ◽  
Maternal Antibody ◽  
Canine Distemper ◽  
Parenteral Immunization ◽  
Multiple Routes ◽  
Antibody Titers ◽  
Group 3 ◽  
Rabies Glycoprotein

ABSTRACT Canine distemper virus (CDV) infection of ferrets is clinically and immunologically similar to measles, making this a useful model for the human disease. The model was used to determine if parenteral or mucosal immunization of infant ferrets at 3 and 6 weeks of age with attenuated vaccinia virus (NYVAC) or canarypox virus (ALVAC) vaccine strains expressing the CDV hemagglutinin (H) and fusion (F) protein genes (NYVAC-HF and ALVAC-HF) would induce serum neutralizing antibody and protect against challenge infection at 12 weeks of age. Ferrets without maternal antibody that were vaccinated parenterally with NYVAC-HF (n = 5) or ALVAC-HF (n = 4) developed significant neutralizing titers (log10 inverse mean titer ± standard deviation of 2.30 ± 0.12 and 2.20 ± 0.34, respectively) by the day of challenge, and all survived with no clinical or virologic evidence of infection. Ferrets without maternal antibody that were vaccinated intranasally (i.n.) developed lower neutralizing titers, with NYVAC-HF producing higher titers at challenge (1.11 ± 0.57 versus 0.40 ± 0.37, P = 0.02) and a better survival rate (6/7 versus 0/5, P = 0.008) than ALVAC-HF. Ferrets with maternal antibody that were vaccinated parenterally with NYVAC-HF (n = 7) and ALVAC-HF (n = 7) developed significantly higher antibody titers (1.64 ± 0.54 and 1.28 ± 0.40, respectively) than did ferrets immunized with an attenuated CDV vaccine (0.46 ± 0.59;n = 7) or the recombinant vectors expressing rabies glycoprotein (RG) (0.19 ± 0.32; n = 8,P = 7 × 10−6). The NYVAC vaccine also protected against weight loss, and both the NYVAC and attenuated CDV vaccines protected against the development of some clinical signs of infection, although survival in each of the three vaccine groups was low (one of seven) and not significantly different from the RG controls (none of eight). Combined i.n.-parenteral immunization of ferrets with maternal antibody using NYVAC-HF (n = 9) produced higher titers (1.63 ± 0.25) than did i.n. immunization with NYVAC-HF (0.88 ± 0.36; n = 9) and ALVAC-HF (0.61 ± 0.43; n = 9, P = 3 × 10−7), and survival was also significantly better in the i.n.-parenteral group (3 of 9) than in the other HF-vaccinated animals (none of 18) or in controls immunized with RG (none of 5) (P = 0.0374). Multiple routes were not tested with the ALVAC vaccine. The results suggest that infant ferrets are less responsive to i.n. vaccination than are older ferrets and raises questions about the appropriateness of this route of immunization in infant ferrets or infants of other species.

Histopathologic lesions in conventional pigs experimentally infected with Haemophilus parasuis serovar 5

2015 ◽  
Vol 43 (02) ◽  
pp. 91-96 ◽  
Author(s):  
R.-L. Austin-Busse ◽  
A. Ladinig ◽  
G. Balka ◽  
S. Zoels ◽  
M. Ritzmann ◽  
...  
Keyword(s):  
Clinical Signs ◽  
Control Group ◽  
Post Inoculation ◽  
Haemophilus Parasuis ◽  
Tissue Samples ◽  
Group A ◽  
Pathologic Lesions ◽  
Group B ◽  
Kidney Lesions ◽  
Challenge Group

Summary Objective: In the present study various tissues of pigs were investigated for the presence of histopathologic lesions after an experimental infection with Haemophilus (H.) parasuis serovar 5. Material and methods: Conventional pigs (n = 36) were divided into a control group B (n = 9) and a challenge group A (n = 27), which was infected intratracheally. Pigs that did not die prior to study termination were euthanized on day 14 post inoculation. Postmortem samples of the lung, heart, liver, kidney, spleen, left tarsal joint capsule and brain were collected. Results: All but one pig with detectable histopathologic lesions (n = 11) showed typical macroscopic changes. Histopatho logic examination of all tissue samples identified pyelitis (n = 10), synovitis (n = 7) and meningitis (n = 7) and all those animals were euthanized prior to study termination. No histopathologic lesions were found in pigs of the control group. The correlations between pyelitis and meningitis, pyelitis and synovitis and synovitis and meningitis were significant (p < 0.001). No significant correlation could be observed between the histopathologic and the clinical examination of the joints. The investigation of samples from the joints by PCR was not significantly correlated with the observed synovitis. The clinical observation of neurologic signs was significantly correlated with meningitis (p = 0.03). A significant correlation (p < 0.001) could be detected between meningitis and the detection of H. parasuis by PCR in brain samples. Conclusions: H. parasuis constantly causes clinical signs and pathologic lesions as soon as it infects the brain while it can infect the joints without causing histopathologic lesions. Pigs with histopathologic lesions do not always show typical clinical signs. Only few studies described the finding of kidney lesions in pigs with Glässer’s disease and this is the first study to describe a pyelitis in pigs experimentally infected with H. parasuis. The observed pyelitis mainly occurred in acute cases.

scholarly journals Pathogenicity of an African swine fever virus strain isolated in Vietnam and alternative diagnostic specimens for early detection of viral infection

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Hu Suk Lee ◽  
Vuong Nghia Bui ◽  
Duy Tung Dao ◽  
Ngoc Anh Bui ◽  
Thanh Duy Le ◽  
...  
Keyword(s):  
Early Detection ◽  
Oral Fluid ◽  
African Swine Fever Virus ◽  
Fluid Collection ◽  
Clinical Signs ◽  
African Swine Fever ◽  
Post Inoculation ◽  
Tissue Samples ◽  
Viral Loads ◽  
Specimen Collection

Abstract Background African swine fever (ASF), caused by the ASF virus (ASFV), was first reported in Vietnam in 2019 and spread rapidly thereafter. Better insights into ASFV characteristics and early detection by surveillance could help control its spread. However, the pathogenicity and methods for early detection of ASFV isolates from Vietnam have not been established. Therefore, we investigated the pathogenicity of ASFV and explored alternative sampling methods for early detection. Results Ten pigs were intramuscularly inoculated with an ASFV strain from Vietnam (titer, 103.5 HAD50/mL), and their temperature, clinical signs, and virus excretion patterns were recorded. In addition, herd and environmental samples were collected daily. The pigs died 5–8 days-post-inoculation (dpi), and the incubation period was 3.7 ± 0.5 dpi. ASFV genome was first detected in the blood (2.2 ± 0.8) and then in rectal (3.1 ± 0.7), nasal (3.2 ± 0.4), and oral (3.6 ± 0.7 dpi) swab samples. ASFV was detected in oral fluid samples collected using a chewed rope from 3 dpi. The liver showed the highest viral loads, and ear tissue also exhibited high viral loads among 11 tissues obtained from dead pigs. Overall, ASFV from Vietnam was classified as peracute to acute form. The rope-based oral fluid collection method could be useful for early ASFV detection and allows successful ASF surveillance in large pig farms. Furthermore, ear tissue samples might be a simple alternative specimen for diagnosing ASF infection in dead pigs. Conclusions Our data provide valuable insights into the characteristics of a typical ASFV strain isolated in Vietnam and suggest an alternative, non-invasive specimen collection strategy for early detection.

scholarly journals Genetic and phenotypic analysis of the pathogenic potential of two novel Chlamydia gallinacea strains compared to Chlamydia psittaci

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marloes Heijne ◽  
Martina Jelocnik ◽  
Alexander Umanets ◽  
Michael S. M. Brouwer ◽  
Annemieke Dinkla ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Opportunistic Pathogen ◽  
Chlamydia Psittaci ◽  
Phenotypic Analysis ◽  
Pathogenic Potential ◽  
The Family ◽  
Chicken Eggs ◽  
Sequence Types ◽  
Insight Into ◽  
Embryonated Chicken

AbstractChlamydia gallinacea is an obligate intracellular bacterium that has recently been added to the family of Chlamydiaceae. C. gallinacea is genetically diverse, widespread in poultry and a suspected cause of pneumonia in slaughterhouse workers. In poultry, C. gallinacea infections appear asymptomatic, but studies about the pathogenic potential are limited. In this study two novel sequence types of C. gallinacea were isolated from apparently healthy chickens. Both isolates (NL_G47 and NL_F725) were closely related to each other and have at least 99.5% DNA sequence identity to C. gallinacea Type strain 08-1274/3. To gain further insight into the pathogenic potential, infection experiments in embryonated chicken eggs and comparative genomics with Chlamydia psittaci were performed. C. psittaci is a ubiquitous zoonotic pathogen of birds and mammals, and infection in poultry can result in severe systemic illness. In experiments with embryonated chicken eggs, C. gallinacea induced mortality was observed, potentially strain dependent, but lower compared to C. psittaci induced mortality. Comparative analyses confirmed all currently available C. gallinacea genomes possess the hallmark genes coding for known and potential virulence factors as found in C. psittaci albeit to a reduced number of orthologues or paralogs. The presence of potential virulence factors and the observed mortality in embryonated eggs indicates C. gallinacea should rather be considered as an opportunistic pathogen than an innocuous commensal.

Susceptibility of Common Family Anatidae Bird Species to Clade 2.3.4.4e H5N6 High Pathogenicity Avian Influenza Virus: An Experimental Infection Study

2021 ◽  
Author(s):  
Kosuke Soda ◽  
Yukiko Tomioka ◽  
Chiharu Hidaka ◽  
Mayu Matsushita ◽  
Tatsufumi Usui ◽  
...  
Keyword(s):  
Avian Influenza ◽  
Late Phase ◽  
Clinical Signs ◽  
Bird Species ◽  
Oral Route ◽  
Post Inoculation ◽  
Infectious Dose ◽  
Epidemic Season ◽  
Source Of Infection ◽  
High Pathogenicity

Abstract Background: There were large outbreaks of high pathogenicity avian influenza (HPAI) caused by clade 2.3.4.4e H5N6 viruses in the winter of 2016–2017 in Japan, which caused large numbers of deaths among several endangered bird species including cranes, raptors, and birds in Family Anatidae. In this study, susceptibility of common Anatidae to a clade 2.3.4.4e H5N6 HPAI virus was assessed to evaluate their potential to be a source of infection for other birds. Eurasian wigeons (Mareca penelope), mallards (Anas platyrhynchos), and Northern pintails (Anas acuta) were intranasally inoculated with 106, 104, or 102 50% egg infectious dose (EID50) of clade 2.3.4.4e A/teal/Tottori/1/2016 (H5N6). Results: All birds survived for 10 days without showing any clinical signs of infection. Most ducks inoculated with ≥104 EID50 of virus seroconverted within 10 days post-inoculation (dpi). Virus was mainly shed via the oral route for a maximum of 10 days, followed by cloacal route in late phase of infection. Virus remained in the pancreas of some ducks at 10 dpi. Viremia was observed in some ducks euthanized at 3 dpi, and ≤106.3 EID50 of virus was recovered from systemic tissues and swab samples including eyeballs and conjunctival swabs. Conclusions: These results indicate that the subject duck species have a potential to be a source of infection of clade 2.3.4.4e HPAI virus to the environment and other birds sharing their habitats. Captive ducks should be reared under isolated or separated circumstances during the HPAI epidemic season to prevent infection and further viral dissemination.

scholarly journals Experimental exposure of pregnant mares to the asinine-94 strain of equine arteritis virus

1997 ◽  
Vol 68 (2) ◽  
Author(s):  
J.T. Paweska ◽  
M.M. Henton ◽  
J.J. Van der Lugt
Keyword(s):  
Close Contact ◽  
Post Partum ◽  
Clinical Signs ◽  
Buffy Coat ◽  
Equine Arteritis Virus ◽  
Post Inoculation ◽  
Challenge Virus ◽  
Clinically Normal ◽  
Detectable Concentration ◽  
Specific Igg

Clinical, virological and serological responses were evaluated in 10 pregnant mares after different challenge exposures to the asinine-94 strain of equine arteritis virus (EAV). The outcome of maternal infection on the progeny was also investigated. Mares were inoculated intranasally (n = 4), intramuscularly (n = 2), intravenously (n = 1), or contact-exposed (n = 3). All inoculated mares developed pyrexia, 5 showed mild clinical signs related to EAV infection and 2 remained asymptomatic. Viraemia was detected in all the inoculated animals and shedding of virus from the respiratory tract occurred in 6. Five mares were re-challenged intranasally 7 and 15 weeks after inoculation. Clinical signs of the disease in these mares were limited to mild conjunctivitis. After re-challenge, virus was recovered from buffy coat cultures of 2 mares 2-6 days after re-infection. EAV was not recovered from colostrum and milk samples during the 1st week post partum. All inoculated mares seroconverted to EAV 8-12 days post inoculation and also seroconverted after re-challenge. No clinical signs of EAV infection were observed in the 3 mares kept in close contact during the post-inoculation and re-challenge periods. Serum neutralising antibody to the virus was detected in 1 in-contact mare only, while a detectable concentration of specific IgG was found by ELISA in the colostrum of 1 of the other in-contact mares. Eight of the mares gave birth to clinically normal foals, although 1 was born prematurely. Shortly after birth, 7 foals developed fever and variable clinical signs; 5 foals became septicaemic and 3 of them died 2-5 days after birth, while the remaining 2 were euthanased at 1 month of age. EAV was not recovered from the placenta, from buffy coat fractions of blood collected from foals immediately after birth and 1-3 days later, or from a range of tissues taken from the 3 foals that died and 2 that were euthanased. Virus was not isolated from tissues collected from 1 mare and her foetus 3 weeks after this mare was re-challenged.

Sign in / Sign up

Export Citation Format

Share Document