http://www.veterinaryresearch.org The latest research articles published by Veterinary Research 2013-06-13T00:00:00Z Avian influenza virus (AIV) is enzootic to wild birds, which are its natural reservoir. The virus exhibits a large degree of genetic diversity and most of the isolated strains are of low pathogenicity to poultry. Although AIV is nearly ubiquitous in wild bird populations, highly pathogenic H5N1 subtypes in poultry have been the focus of most modeling efforts. To better understand viral ecology of AIV, a predictive model should 1) include wild birds, 2) include all isolated subtypes, and 3) cover the host's natural range, unbounded by artificial country borders. As of this writing, there are few large-scale predictive models of AIV in wild birds. We used the Random Forests algorithm, an ensemble data-mining machine-learning method, to develop a global-scale predictive map of AIV, identify important predictors, and describe the environmental niche of AIV in wild bird populations. The model has an accuracy of 0.79 and identified northern areas as having the highest relative predicted risk of outbreak. The primary niche was described as regions of low annual rainfall and low temperatures. This study is the first global-scale model of low-pathogenicity avian influenza in wild birds and underscores the importance of largely unstudied northern regions in the persistence of AIV. http://www.veterinaryresearch.org/content/44/1/42 Keiko Herrick Falk Huettmann Michael Lindgren Veterinary Research 2013, null:42 2013-06-13T00:00:00Z doi:10.1186/1297-9716-44-42 A global model of avian influenza prediction in wild birds <p>Keiko Herrick and colleagues used machine-learning algorithms and data mining to form a predictive ecological model of Avian Influenza Virus in wild bird populations, identifying specific northern regions at high risk of outbreak.</p> /content/figures/1297-9716-44-42-toc.gif Veterinary Research 1297-9716 ${item.volume} 42 2013-06-13T00:00:00Z PDF Since the emergence of the 2009 pandemic (H1N1) virus (2009/H1N1) in April 2009, cases of transmission from humans to pigs have been reported frequently. In our previous studies, four 2009/H1N1 variants were isolated from pigs. To better understand the phenotypic differences of the pig isolates compared with the human isolate, in this study mice were inoculated intranasally with different 2009/H1N1 viruses, and monitored for morbidity, mortality, and viral replication, cytokine production and pathological changes in the lungs. The results show that all isolates show effective replication in lungs, but varying in their ability to cause morbidity. In particular, the strains of A/swine/Nanchang/3/2010 (H1N1) and A/swine/Nanchang/F9/2010 (H1N1) show the greatest virulence with a persisting replication in lungs and high lethality for mice, compared with the human isolate A/Liaoning /14/2009 (H1N1), which shows low virulence in mice. Furthermore, the lethal strains could induce more severe lung pathological changes and higher production of cytokines than that of other strains at an early stage. Amino acid sequence analysis illustrates prominent differences in viral surface glycoproteins and polymerase subunits between pig isolates and human strains that might correlate with their phenotypic differences. These studies demonstrate that the 2009/H1N1 pig isolates exhibit heterogeneous infectivity and pathogencity in mice, and some strains possess an enhanced pathogenicity compared with the human isolate. http://www.veterinaryresearch.org/content/44/1/41 Yongtao Li Wei Zou Guangmin Jia Jianjiang Ke Jiping Zhu Xian Lin Hongbo Zhou Meilin Jin Veterinary Research 2013, null:41 2013-06-11T00:00:00Z doi:10.1186/1297-9716-44-41 /content/figures/1297-9716-44-41-toc.gif Veterinary Research 1297-9716 ${item.volume} 41 2013-06-11T00:00:00Z PDF Mastitis caused by Escherichia coli and Staphylococcus aureus is a major pathology of dairy cows. To better understand the differential response of the mammary gland to these two pathogens, we stimulated bovine mammary epithelial cells (bMEC) with either E. coli crude lipopolysaccharide (LPS) or with S. aureus culture supernatant (SaS) to compare the transcriptomic profiles of the initial bMEC response. By using HEK 293 reporter cells for pattern recognition receptors, the LPS preparation was found to stimulate TLR2 and TLR4 but not TLR5, Nod1 or Nod2, whereas SaS stimulated TLR2. Biochemical analysis revealed that lipoteichoic acid, protein A and alpha-hemolysin were all present in SaS, and bMEC were found to be responsive to each of these molecules. Transcriptome profiling revealed a core innate immune response partly shared by LPS and SaS. However, LPS induced expression of a significant higher number of genes and the fold changes were of greater magnitude than those induced by SaS. Microarray data analysis suggests that the activation pathways and the early chemokine and cytokine production preceded the defense and stress responses. A major differential response was the activation of the type I IFN pathway by LPS but not by SaS. The higher upregulation of chemokines (Cxcl10, Ccl2, Ccl5 and Ccl20) that target mononuclear leucocytes by LPS than by SaS is likely to be related to the differential activation of the type I IFN pathway, and could induce a different profile of the initial recruitment of leucocytes. The MEC responses to the two stimuli were different, as LPS was associated with NF-kappaB and Fas signaling pathways, whereas SaS was associated with AP-1 and IL-17A signaling pathways. It is noteworthy that at the protein level secretion of TNF-alpha and IL-1beta was not induced by either stimulus. These results suggest that the response of MEC to diffusible stimuli from E. coli and S. aureus contributes to the onset of the response with differential leucocyte recruitment and distinct inflammatory and innate immune reactions of the mammary gland to infection. http://www.veterinaryresearch.org/content/44/1/40 Florence Gilbert Patricia Cunha Kirsty Jensen Elizabeth Glass Gilles Foucras Christèle Robert-Granié Rachel Rupp Pascal Rainard Veterinary Research 2013, null:40 2013-06-11T00:00:00Z doi:10.1186/1297-9716-44-40 /content/figures/1297-9716-44-40-toc.gif Veterinary Research 1297-9716 ${item.volume} 40 2013-06-11T00:00:00Z PDF : West Nile virus (WNV) is a globally distributed arthropod-borne flavivirus capable of infecting a wide variety of vertebrates, with birds as its natural reservoir. Although it had been considered a pathogen of little importance for birds, from the 1990's, and especially after its introduction in the North American continent in 1999, thousands of birds have succumbed to West Nile infection. This review summarizes the pathogenesis and pathology of WNV infection in birds highlighting differences in lesion and antigen distribution and severity among bird orders and families. Despite significant species differences in susceptibility to infection, WNV associated lesions and viral antigen are present in the majority of organs of infected birds. The non-progressive, acute or more prolonged course of the disease accounts for part of the differences in lesion and viral antigen distribution and lesion severity. Most likely a combination of host variables and environmental factors in addition to the intrinsic virulence and pathogenicity of the infecting WNV strain influence the pathogenesis of the infection. http://www.veterinaryresearch.org/content/44/1/39 Virginia Gamino Ursula Höfle Veterinary Research 2013, null:39 2013-06-03T00:00:00Z doi:10.1186/1297-9716-44-39 /content/figures/1297-9716-44-39-toc.gif Veterinary Research 1297-9716 ${item.volume} 39 2013-06-03T00:00:00Z PDF In the present study day-old specific-pathogen-free (SPF) and commercial broilers with maternally derived fowl adenovirus serotype 1 (FAdV-1) antibodies were orally infected with a European “pathogenic” FAdV-1, isolated from broilers showing signs of gizzard erosion. During the experiment, broilers were observed and weighed daily up to 17 days post infection (dpi). Clinically, both infected groups showed significant decrease of weight compared to respective negative control groups. Birds were examined by necropsy at 3, 7, 10, 14 and 17 dpi. Pathological changes in the gizzards were noticed in both experimentally infected groups from 7 dpi onwards. Macroscopically, erosion of the koilin layer and inflammation or ulceration of the gizzard mucosa were observed. Histologically, presence of FAdV-1 in intranuclear inclusion bodies of degenerated glandular epithelial cells was demonstrated by in-situ hybridization and inflammatory cell infiltration of the lamina propria, submucosa and muscle layer was detected. Tissue samples were investigated by a recently developed real-time PCR and the viral DNA load was calculated from gizzard, liver, spleen and cloacal swabs with the highest amounts of FAdV-1 DNA found in the gizzard. For the first time, successful reproduction of clinical signs in broilers as well as pathological lesions in the gizzard were achieved with a European FAdV-1 isolate displaying some genetic differences to so far reported virulent FAdV-1 from Japan. Furthermore, highest viral load in gizzards could be linked with macroscopical and histological lesions. Therefore, the conducted analyses provide important insights into the pathogenesis of adenoviral gizzard erosion. http://www.veterinaryresearch.org/content/44/1/38 Beatrice Grafl Dieter Liebhart Ayse Günes Patricia Wernsdorf Franz Aigner Josef Bachmeier Michael Hess Veterinary Research 2013, null:38 2013-05-24T00:00:00Z doi:10.1186/1297-9716-44-38 /content/figures/1297-9716-44-38-toc.gif Veterinary Research 1297-9716 ${item.volume} 38 2013-05-24T00:00:00Z XML The characterization of the immune response of chickens to Salmonella infection is usually limited to the quantification of expression of genes coding for cytokines, chemokines or antimicrobial peptides. However, processes occurring in the cecum of infected chickens are likely to be much more diverse. In this study we have therefore characterized the transcriptome and proteome in the chicken cecum after infection with Salmonella Enteritidis. Using a combination of 454 pyrosequencing, protein mass spectrometry and quantitative real-time PCR, we identified 48 down- and 56 up-regulated chicken genes after Salmonella Enteritidis infection. The most inducible gene was that coding for MMP7, exhibiting a 5952 fold induction 9 days post-infection. An induction of greater than 100 fold was observed for IgG, IRG1, SAA, ExFABP, IL-22, TRAP6, MRP126, IFNγ, iNOS, ES1, IL-1β, LYG2, IFIT5, IL-17, AVD, AH221 and SERPIN B. Since prostaglandin D2 synthase was upregulated and degrading hydroxyprostaglandin dehydrogenase was downregulated after the infection, prostaglandin must accumulate in the cecum of chickens infected with Salmonella Enteritidis. Finally, above mentioned signaling was dependent on the presence of a SPI1-encoded type III secretion system in Salmonella Enteritidis. The inflammation lasted for 2 weeks after which time the expression of the “inflammatory” genes returned back to basal levels and, instead, the expression of IgA and IgG increased. This points to an important role for immunoglobulins in the restoration of homeostasis in the cecum after infection. http://www.veterinaryresearch.org/content/44/1/37 Marta Matulova Karolina Varmuzova Frantisek Sisak Hana Havlickova Vladimir Babak Karel Stejskal Zbynek Zdrahal Ivan Rychlik Veterinary Research 2013, null:37 2013-05-20T00:00:00Z doi:10.1186/1297-9716-44-37 /content/figures/1297-9716-44-37-toc.gif Veterinary Research 1297-9716 ${item.volume} 37 2013-05-20T00:00:00Z XML Pet birds are a not-so-well known veterinarian’s clientship fraction. Bought individually or in couples, as families often do (which is a lucrative business for pet shops or local breeders) or traded (sometimes illegally) for their very high genetic or exotic value, these birds, commonly canaries, parakeets or parrots, are regularly sold at high prices. These animals, however, are potential carriers and/or transmitters of zoonotic diseases. Some of them could have an important impact on human health, like chlamydophilosis, salmonellosis or even highly pathogenic avian influenza A H5N1. This review paper, although non exhaustive, aims at enlightening, by the description of several cases of bird-human transmission, the risks encountered by bird owners, including children. Public health consequences will be discussed and emphasis will be made on some vector-borne diseases, known to be emergent or which are underestimated, like those transmitted by the red mite Dermanyssus gallinae. Finally, biosecurity and hygiene, as well as prevention guidelines will be developed and perspectives proposed. http://www.veterinaryresearch.org/content/44/1/36 Geraldine Boseret Bertrand Losson Jacques Mainil Etienne Thiry Claude Saegerman Veterinary Research 2013, null:36 2013-05-20T00:00:00Z doi:10.1186/1297-9716-44-36 Zoonoses in pet birds <p>Geraldine Boseret and colleagues address the biosecurity and hygiene concerns of human contact with pet birds, describing the risk of zoonotic infection with salmonellosis, avian influenza A H5N1 and other diseases.</p> /content/figures/1297-9716-44-36-toc.gif Veterinary Research 1297-9716 ${item.volume} 36 2013-05-20T00:00:00Z XML Salmonella enterica serovar Typhimurium (Salmonella Typhimurium) infection of chickens that are more than a few days old results in asymptomatic cecal colonization with persistent shedding of bacteria. We hypothesized that while the bacterium colonizes and persists locally in the cecum it has systemic effects, including changes to metabolic pathways of skeletal muscle, influencing the physiology of the avian host. Using species-specific peptide arrays to perform kinome analysis on metabolic signaling pathways in skeletal muscle of Salmonella Typhimurium infected chickens, we have observed key metabolic changes that affected fatty acid and glucose metabolism through the 5'-adenosine monophosphate-activated protein kinase (AMPK) and the insulin/mammalian target of rapamycin (mTOR) signaling pathway. Over a three week time course of infection, we observed changes in the phosphorylation state of the AMPK protein, and proteins up and down the pathway. In addition, changes to a large subset of the protein intermediates of the insulin/mTOR pathway in the skeletal muscle were altered by infection. These changes occur in pathways with direct effects on fatty acid and glucose metabolism. This is the first report of significant cellular metabolic changes occurring systemically in chicken due to a Salmonella infection. These results have implications not only for animal production and health but also for the understanding of how Salmonella infection in the intestine can have widespread, systemic effects on the metabolism of chickens without disease-like symptoms. http://www.veterinaryresearch.org/content/44/1/35 Ryan Arsenault Scott Napper Michael Kogut Veterinary Research 2013, null:35 2013-05-17T00:00:00Z doi:10.1186/1297-9716-44-35 /content/figures/1297-9716-44-35-toc.gif Veterinary Research 1297-9716 ${item.volume} 35 2013-05-17T00:00:00Z XML The bacterium Flavobacterium psychrophilum is a serious problem for salmonid farming worldwide. This study investigates by multilocus sequence typing (MLST) the population structure of this pathogen in Japan where it is also a major concern for ayu, a popular game fish related to salmoniforms. A total of 34 isolates collected across the country and 80 isolates sampled in a single model river by electrofishing were genotyped. The data accounting for 15 fish species allowed identifying 35 distinct sequence types (ST) in Japan. These ST are distinct from those reported elsewhere, except for some ST found in rainbow trout and coho salmon, two fish that have been the subject of intensive international trade. The pattern of polymorphism is, however, strikingly similar across geographical scales (model river, Japan, world) in terms of the fraction of molecular variance linked to the fish host (~50%) and of pairwise nucleotide diversity between ST (~5 Kbp-1). These observations go against the hypothesis of a recent introduction of F. psychrophilum in Japan. Two findings were made that are important for disease control: 1) at least two independent F. psychrophilum lineages infect ayu and 2) co-infections of the same individual fish by different strains occur. http://www.veterinaryresearch.org/content/44/1/34 Erina Fujiwara-Nagata Céline Chantry-Darmon Jean-François Bernardet Mitsuru Eguchi Eric Duchaud Pierre Nicolas Veterinary Research 2013, null:34 2013-05-17T00:00:00Z doi:10.1186/1297-9716-44-34 /content/figures/1297-9716-44-34-toc.gif Veterinary Research 1297-9716 ${item.volume} 34 2013-05-17T00:00:00Z XML After the unexpected emergence of Bluetongue virus serotype 8 (BTV-8) in northern Europe in 2006, another arbovirus, Schmallenberg virus (SBV), emerged in Europe in 2011 causing a new economically important disease in ruminants. The virus, belonging to the Orthobunyavirus genus in the Bunyaviridae family, was first detected in Germany, in The Netherlands and in Belgium in 2011 and soon after in the United Kingdom, France, Italy, Luxembourg, Spain, Denmark and Switzerland. This review describes the current knowledge on the emergence, epidemiology, clinical signs, molecular virology and diagnosis of SBV infection. http://www.veterinaryresearch.org/content/44/1/31 Virginie Doceul Estelle Lara Corinne Sailleau Guillaume Belbis Jennifer Richardson Emmanuel Bréard Cyril Viarouge Morgane Dominguez Pascal Hendrikx Didier Calavas Alexandra Desprat Jérôme Languille Loïc Comtet Philippe Pourquier Jean-François Eléouët Bernard Delmas Philippe Marianneau Damien Vitour Stéphan Zientara Veterinary Research 2013, null:31 2013-05-15T00:00:00Z doi:10.1186/1297-9716-44-31 Epidemiology and molecular virology of Schmallenberg virus <p>Schmallenberg virus (SBV) emerged in 2011 as a new livestock disease, causing&nbsp;late abortion or birth defects in cattle, goats and sheep. Virginie Doceul and colleagues review the emergence, epidemiology, clinical signs and molecular virology of SBV.</p> /content/figures/1297-9716-44-31-toc.gif Veterinary Research 1297-9716 ${item.volume} 31 2013-05-15T00:00:00Z XML