| 1. |
- Blodörn, Krister, et al.
(författare)
-
A bovine respiratory syncytial virus model with high clinical expression in calves with specific passive immunity
- 2015
-
Ingår i: BMC Veterinary Research. - : Springer Science and Business Media LLC. - 1746-6148. ; 11
-
Tidskriftsartikel (refereegranskat)abstract
- Background Bovine respiratory syncytial virus (BRSV) is a major cause of respiratory disease in cattle worldwide. Calves are particularly affected, even with low to moderate levels of BRSV-specific maternally derived antibodies (MDA). Available BRSV vaccines have suboptimal efficacy in calves with MDA, and published infection models in this target group are lacking in clinical expression. Here, we refine and characterize such a model. Results In a first experiment, 2 groups of 3 calves with low levels of MDA were experimentally inoculated by inhalation of aerosolized BRSV, either: the Snook strain, passaged in gnotobiotic calves (BRSV-Snk), or isolate no. 9402022 Denmark, passaged in cell culture (BRSV-Dk). All calves developed clinical signs of respiratory disease and shed high titers of virus, but BRSV-Snk induced more severe disease, which was then reproduced in a second experiment in 5 calves with moderate levels of MDA. These 5 calves shed high titers of virus and developed severe clinical signs of disease and extensive macroscopic lung lesions (mean+/−SD, 48.3+/−12.0% of lung), with a pulmonary influx of inflammatory cells, characterized by interferon gamma secretion and a marked effect on lung function. Conclusions We present a BRSV-infection model, with consistently high clinical expression in young calves with low to moderate levels of BRSV-specific MDA, that may prove useful in studies into disease pathogenesis, or evaluations of vaccines and antivirals. Additionally, refined tools to assess the outcome of BRSV infection are described, including passive measurement of lung function and a refined system to score clinical signs of disease. Using this cognate host calf model might also provide answers to elusive questions about human RSV (HRSV), a major cause of morbidity in children worldwide.
|
|
| 2. |
- Bröjer, Caroline, et al.
(författare)
-
Pathobiology and virus shedding of low-pathogenic avian influenza virus (A/H1N1) infection in mallards exposed to oseltamivir
- 2013
-
Ingår i: Journal of Wildlife Diseases. - : Wildlife Disease Association. - 0090-3558 .- 1943-3700. ; 49:1, s. 103-113
-
Tidskriftsartikel (refereegranskat)abstract
- Low-pathogenic avian influenza (LPAI) viruses in wild birds are important as they can constitute the basis for the development of highly pathogenic avian influenza viruses or form part of human-adapted strains with pandemic potential. However, the pathogenesis of LPAI viruses is not well characterized in dabbling ducks, one of the natural reservoirs of LPAI viruses. Between 21 September 2009 and 21 December 2009, we used real-time reverse transcriptase polymerase chain reaction (q-PCR), histopathology, and immunohistochemistry (IHC) to study Mallards (Anas platyrhynchos) infected with an influenza A/H1N1 virus isolated from a wild Mallard in Sweden. The ducks were either inoculated intraesophageally ("artificial infection") or infected by virus shed by other ducks in the experiment ("contact infection"). The ducks were subjected to three low concentrations (80 ng/L, 1 mu g/L, and 80 mu g/L) of the active metabolite of oseltamivir (Tamiflu (R)), oseltamivir carboxylate (OC), which resulted in the development of the viral resistance mutation H274Y at 1 and 80 mu g/L. The LPAI virus infection was localized to the intestinal tract and cloacal bursa except in one Mallard. The exception was a duck euthanized 1 day postinoculation, whose infection was located solely in the lung, possibly due to intratracheal deposition of virus. The intestinal infection was characterized by occasional degenerating cells in the lamina propria and presence of viral antigen as detected by IHC, as well as positive q-PCR performed on samples from feces and intestinal contents. Histopathologic changes, IHC positivity, and viral shedding all indicated that the infection peaked early, around 2 days postinfection. Furthermore, more viral antigen and viral RNA were detected with IHC and q-PCR in the proximal parts early in the infection. There was no obvious difference in the course of the infection in artificial versus contact infection, when the level of OC was increased from 80 ng/L to 1 mu g/L (based on IHC and q-PCR), when the level of OC was increased to 80 mu/L, or when the resistance mutation H274Y developed (based on q-PCR).
|
|
| 3. |
- Gavier-Widén, Dolores
(författare)
-
Prioritisation of wildlife pathogens to be targeted in European surveillance programmes: Expert-based risk analysis focus on ruminants
- 2015
-
Ingår i: Preventive Veterinary Medicine. - : Elsevier BV. - 0167-5877 .- 1873-1716. ; 118, s. 271-284
-
Tidskriftsartikel (refereegranskat)abstract
- This study attempted to develop a list of priority pathogens. It is part of a European Union (EU) project dedicated to the surveillance of emerging or re-emerging pathogens of wildlife. Partners of the consortium established an initial list of 138 pathogens of concern, which was reduced to a smaller list of 65 pathogens likely to affect ruminants (i.e., the most costly animal group in the EU over the last 15 years). These 65 pathogens underwent a two-step, expert-based risk analysis: 92 experts graded them with respect to their global importance for animal welfare, species conservation, trade/economic impacts and public health. In step 2, the top 15 pathogens from step 1 were assessed by 69 experts considering seven weighted epidemiological criteria (pathogen variability, host specificity, potential for contagion, speed of spread, presence in Europe, difficulty of surveillance in wildlife and persistence in the environment) for which four options were possible. The responses concerned a wide geographic coverage. The resulting top-list pathogens were ranked as follows: 1. Salmonella enterica, 2. Coxiella burnetii, 3. foot-and-mouth disease virus, 4. Mycobacterium bovis, 5. bluetongue virus, and 6. European tick-borne encephalitis virus. The influence of the characteristics of the respondents, the importance of the levels of uncertainty/variability and the implication of the results are discussed. This work highlights the relevance of developing such lists for preparedness. (C) 2014 Elsevier B.V. All rights reserved.
|
|
| 4. |
- Axner, Eva, et al.
(författare)
-
Macroscopic and microscopic evaluation of Eurasian lynx (Lynx lynx) female tubular reproductive organs in relation to ovarian structures
- 2015
-
Ingår i: Theriogenology. - : Elsevier BV. - 0093-691X .- 1879-3231. ; 84, s. 710-715
-
Tidskriftsartikel (refereegranskat)abstract
- Although monitoring wild animals in the field is essential for estimations of population size and development, there are pitfalls associated with field monitoring. In addition, some detailed data about reproductive physiology can be difficult to obtain in wild live animals. Studying reproductive organs from the Eurasian lynx killed at hunting or found dead could be used as a valuable addition to other field data. We evaluated reproductive organs from 39 Eurasian lynx females (Lynx lynx) killed in Sweden during the hunting seasons in 2009, 2010, and 2011. According to notes on ovarian structures, the animals were categorized as being in one of four different reproductive stages: juvenile (n = 10), follicular stage (n = 8), luteal stage (n = 11), and anestrus (n = 10). Corpora lutea were classified as fresh CL from the present season or as luteal bodies from previous cycles. Microscopic evaluations were blindly coded while the outer measurements of the vagina and uterus were taken at the time of organ retrieval. The width of the endometrium, myometrium, outer width of the uterine horns, and the diameter of the vagina differed significantly with the reproductive stage (P < 0.001) and were largest in the follicular and luteal phases. The number of endometrial glands evaluated blindly coded on a subjective scale was significantly associated with the reproductive stage (P < 0.0001) and was significantly higher in the luteal phase than that in any other reproductive stages (P < 0.05). Cornification of the vaginal epithelium was only observed in females in the follicular stage or in females with signs of a recent ovulation. In conclusion, both macroscopic and histologic measurements are useful for a correct classification of the reproductive stage when evaluating reproductive organs in the Eurasian lynx killed during the hunting season. Routine evaluation of reproductive organs has a potential to be a useful additional tool to field studies of live lynx to monitor their reproduction. (C) 2015 Elsevier Inc. All rights reserved.
|
|
| 5. |
- Gavier-Widén, Dolores
(författare)
-
Characterization of tuberculous lesions in naturally infected African buffalo (Syncerus caffer)
- 2011
-
Ingår i: Journal of Veterinary Diagnostic Investigation. - : SAGE Publications. - 1040-6387 .- 1943-4936. ; 23, s. 1022-1027
-
Tidskriftsartikel (refereegranskat)abstract
- Tuberculosis pathology was studied on 19 African buffalo (Syncerus caffer) from a herd in the Hluhluwe-iMfolozi Park in South Africa. The animals tested positive with the comparative intradermal tuberculin test and were euthanized during a test-and-cull operation to decrease prevalence of bovine tuberculosis (bTB) in the park. The lymph nodes and lungs were examined grossly for presence of tuberculous lesions, which were scored on a 0-5 scale for macroscopic changes. The gross lesions were examined histologically and classified into grade I, II, III, or IV according to a grading system used for bTB lesions in domestic cattle. Macroscopic lesions were limited to the retropharyngeal, bronchial, and mediastinal lymph nodes and the lungs. The most frequently affected lymph nodes were the bronchial (in 16 animals) and mediastinal (in 11 animals). All four grades of microscopic lesions were observed, grade II lesions were the most frequent. Mycobacterium bovis was detected by PCR in 8 out of 19 animals, and acid-fast bacilli were seen in 7 out of 19 animals, together both techniques identified mycobacteria in 5 out of 19 animals. Lesions were paucibacillary, as acid-fast bacilli were only rarely observed. The absence of lesions in the mesenteric lymph nodes and the high frequency of lesions in respiratory tract associated lymph nodes suggest that the main route of M. bovis infection in African buffalo is by inhalation.
|
|
| 6. |
- Gavier-Widén, Dolores
(författare)
-
Tularaemia in Norwegian dogs
- 2014
-
Ingår i: Veterinary Microbiology. - : Elsevier BV. - 0378-1135 .- 1873-2542. ; 173, s. 318-322
-
Tidskriftsartikel (refereegranskat)abstract
- We describe tularaemia in a Norwegian dog caused by Francisella tularensis subspecies holarctica. A Hamilton Hound and his owner developed tulaeremia after hunting an infected mountain hare (Lepus timidus). The dog showed signs of lethargy, anorexia and fever during a period two to four days after hunting and thereafter fully recovered. Its antibody titers increased 32-fold from one to three weeks post exposure. Thereafter, the titer declined and leveled off at moderate positive values up to one year after exposure (end of study). This is believed to be the first case report of clinical F. tularensis subspecies holarctica infection in a European dog.In 2011, enormous numbers of Norway lemmings (Lemmus lemmus) occurred in Finnmark, the northernmost county of Norway and many dogs caught and swallowed lemmings. Some of these dogs developed non-specific signs of disease and the owners consulted a veterinary surgeon, who suspected tularaemia. In order to investigate this hypothesis, serum samples from 33 dogs were examined for antibodies to F. tularensis. The dogs were allocated into three groups: Dogs from Finnmark that became sick (Group 1) or remained healthy following contact with lemmings (Group 2), and healthy control dogs from Oslo without known contact with lemmings (Group 3). All the serum samples were analyzed with a tube agglutination assay. Among dogs exposed to lemmings, 10/11 and 3/12 were antibody positive in Group 1 and Group 2, respectively, whereas none of the control dogs (n = 10) were positive for antibodies against F. tularensis. These results strongly indicate that the non-specific disease seen in the dogs in Finnmark was linked to F. tularensis infection acquired through contact with lemmings. (C) 2014 Elsevier B.V. All rights reserved.
|
|
| 7. |
- Hestvik, Gete, et al.
(författare)
-
The status of tularemia in Europe in a one-health context: a review
- 2015
-
Ingår i: Epidemiology and Infection. - 0950-2688 .- 1469-4409. ; 143, s. 2137-2160
-
Tidskriftsartikel (refereegranskat)abstract
- The bacterium Francisella tularensis causes the vector-borne zoonotic disease tularemia, and may infect a wide range of hosts including invertebrates, mammals and birds. Transmission to humans occurs through contact with infected animals or contaminated environments, or through arthropod vectors. Tularemia has a broad geographical distribution, and there is evidence which suggests local emergence or re-emergence of this disease in Europe. This review was developed to provide an update on the geographical distribution of F. tularensis in humans, wildlife, domestic animals and vector species, to identify potential public health hazards, and to characterize the epidemiology of tularemia in Europe. Information was collated on cases in humans, domestic animals and wildlife, and on reports of detection of the bacterium in arthropod vectors, from 38 European countries for the period 1992-2012. Multiple international databases on human and animal health were consulted, as well as published reports in the literature. Tularemia is a disease of complex epidemiology that is challenging to understand and therefore to control. Many aspects of this disease remain poorly understood. Better understanding is needed of the epidemiological role of animal hosts, potential vectors, mechanisms of maintenance in the different ecosystems, and routes of transmission of the disease.
|
|
| 8. |
- Malmsten, Jonas, et al.
(författare)
-
Temporal and spatial variation in Anaplasma phagocytophilum infection in Swedish moose (Alces alces)
- 2014
-
Ingår i: Epidemiology and Infection. - 0950-2688 .- 1469-4409. ; 142, s. 1205-1213
-
Tidskriftsartikel (refereegranskat)abstract
- The occurrence of Anaplasma phagocytophilum was investigated in spleen and serum samples from Swedish moose (Alces alces) in southern Sweden (island and mainland). Samples were analysed for presence of A. phagocytophilum DNA by real-time PCR (n=263), and for Anaplasma antibodies with ELISA serology (n=234). All serum samples had antibodies against A. phagocytophilum. The mean DNA-based prevalence was 26 center dot 3%, and significant (P<0 center dot 01) temporal, and spatial variation was found. Island moose had significantly (P<0 center dot 001) higher prevalence of A. phagocytophilum DNA than moose from the mainland areas. Two samples were sequenced to determine genetic variation in the 16S rRNA and groESL genes. Genetic sequence similarity with the human granulocytic anaplasmosis agent, equine granulocytic ehrlichiosis agent, and different wildlife-associated A. phagocytophilum variants were observed in the 16S rRNA and groESL genes. Our study shows that moose are exposed to A. phagocytophilum in Sweden, and represent a potential wildlife reservoir of the pathogen.
|
|
| 9. |
- Ottinger, Therese, et al.
(författare)
-
Forensic veterinary pathology, today's situation and perspectives
- 2014
-
Ingår i: Veterinary Record. - : Wiley. - 0042-4900 .- 2042-7670. ; 175
-
Tidskriftsartikel (refereegranskat)abstract
- To investigate the current status of forensic veterinary pathology, a survey was composed directed at pathology laboratories and institutes, mostly in Europe. The questions included number of and type of cases, resources available, level of special training of the investigating pathologists and the general view on the current status and future of the discipline. The surveys were sent to 134 laboratories and were returned by 72 respondents of which 93 per cent work on forensic pathology cases. The results indicate scarcity of training opportunities and special education, and insufficient veterinary-specific reference data and information on forensic analyses. More cooperation with human forensic pathology was desired by many respondents, as was more interaction across country borders.
|
|
| 10. |
- Artois, M., et al.
(författare)
-
Outbreaks of highly pathogenic avian influenza in Europe : the risks associated with wild birds
- 2009
-
Ingår i: Revue scientifique et technique (International Office of Epizootics). - : O.I.E (World Organisation for Animal Health). - 0253-1933 .- 1608-0637. ; 28:1, s. 69-92
-
Forskningsöversikt (refereegranskat)abstract
- The infection of wild birds by highly pathogenic strains of avian influenza (Al) virus was virtually unknown--apart from one instance of the disease appearing in common terns in South Africa in 1961--before the Asian strain of highly pathogenic AI virus (AIV), H5N1, began to expand across the world. Outbreaks of clinical disease in Eurasia have resulted in visible mortality among populations of free-ranging wild birds in a multitude of species. The circulation pattern of influenza viruses in natural ecosystems results from a selection pressure towards strains which are indirectly transmitted by droppings from water birds and contaminated fomites, and which exhibit low pathogenicity. Some of these viruses, of the subtypes H5 or H7, can mutate into highly pathogenic strains after being introduced into domestic poultry farms. The maintenance of highly pathogenic AIV (HPAIV) H5N1 in several parts of the world exposes wild birds to infected poultry, resulting in long-distance virus transmission. There is great concern that these wild birds may, in turn, propagate these HPAIV or introduce them into domestic birds. Rigorous disease control and biosecurity measures to protect poultry farms are the only solution presently available to mitigate such a risk.
|
|
