Canine distemper virus (CDV) is a pantropic morbillivirus with a worldwide distribution, which causes fatal disease in dogs. Affected animals develop dyspnea, diarrhea, neurological signs and ...profound immunosuppression. Systemic CDV infection, resembling distemper in domestic dogs, can be found also in wild canids (e.g. wolves, foxes), procyonids (e.g. raccoons, kinkajous), ailurids (e.g. red pandas), ursids (e.g. black bears, giant pandas), mustelids (e.g. ferrets, minks), viverrids (e.g. civets, genets), hyaenids (e.g. spotted hyenas), and large felids (e.g. lions, tigers). Furthermore, besides infection with the closely related phocine distemper virus, seals can become infected by CDV. In some CDV outbreaks including the mass mortalities among Baikal and Caspian seals and large felids in the Serengeti Park, terrestrial carnivores including dogs and wolves have been suspected as vectors for the infectious agent. In addition, lethal infections have been described in non-carnivore species such as peccaries and non-human primates demonstrating the remarkable ability of the pathogen to cross species barriers. Mutations affecting the CDV H protein required for virus attachment to host-cell receptors are associated with virulence and disease emergence in novel host species. The broad and expanding host range of CDV and its maintenance within wildlife reservoir hosts considerably hampers disease eradication.
A virus isolated from a Natterer's bat (Myotis nattererii) in Germany was differentiated from other lyssaviruses on the basis of the reaction pattern of a panel of monoclonal antibodies. Phylogenetic ...analysis supported the assumption that the isolated virus, Bokeloh bat lyssavirus, may represent a new member of the genus Lyssavirus.
A wide range of viruses from different virus families in different geographical areas, may cause immediate or delayed neuropathological changes and neurological manifestations in humans and animals. ...Infection by neurotropic viruses as well as the resulting immune response can irreversibly disrupt the complex structural and functional architecture of the central nervous system, frequently leaving the patient or affected animal with a poor or fatal prognosis. Mechanisms that govern neuropathogenesis and immunopathogenesis of viral infections are highlighted, using examples of well-studied virus infections that are associated with these alterations in different populations throughout the world. A better understanding of the molecular, epidemiological and biological characteristics of these infections and in particular of mechanisms that underlie their clinical manifestations may be expected to provide tools for the development of more effective intervention strategies and treatment regimens.
Retrospective investigation of archived tissue samples from 3 lions displaying nonsuppurative meningoencephalitis and vasculitis led to the detection of rustrela virus (RusV). We confirmed RusV ...antigen and RNA in cortical neurons, axons, astrocytes and Purkinje cells by reverse transcription quantitative PCR, immunohistochemistry, and in situ hybridization.
This retrospective study provides an overview on spontaneous diseases occurring in 38 captive wild felids submitted for necropsy by German zoological gardens between 2004 and 2013. Species included ...18 tigers, 8 leopards, 7 lions, 3 cheetahs and 2 cougars with an age ranging from 0.5 to 22 years. Renal lesions, predominantly tubular alterations (intra-tubular concrements, tubular degeneration, necrosis, intra-tubular cellular debris, proteinaceous casts, dilated tubuli) followed by interstitial (lympho-plasmacytic inflammation, fibrosis, metastatic-suppurative inflammation, eosinophilic inflammation) and glomerular lesions (glomerulonephritis, glomerulosclerosis, amyloidosis) were detected in 33 out of 38 animals (87%). Tumors were found in 19 of 38 felids (50%) with 12 animals showing more than one neoplasm. The tumor prevalence increased with age. Neoplasms originated from endocrine (11), genital (8), lympho-hematopoietic (5) and alimentary organs (4) as well as the mesothelium (3). Most common neoplasms comprised uterine/ovarian leiomyomas (5/2), thyroid adenomas/adenocarcinoma (5/1), pleural mesotheliomas (3), hemangiosarcomas (2) and glossal papillomas (2). Inflammatory changes were frequently encountered in the intestine and the lung. Two young animals displayed metastatic mineralization suggestive of a vitamin D- or calcium intoxication. One tiger exhibited degenerative white matter changes consistent with an entity termed large felid leukoencephalomyelopathy. Various hyperplastic, degenerative and inflammatory changes with minor clinical significance were found in several organs. Summarized, renal lesions followed by neoplastic changes as well as inflammatory changes in lung and gastrointestinal tract represent the most frequent findings in captive wild felids living in German zoological gardens.
The assumed definitive host of the heartworm Acanthocheilonema spirocauda (Onchocerdidae; Filarioidea) is the harbour seal (Phoca vitulina). This filaroid nematode parasitizing in cardiac ventricles ...and blood vessel lumina of harbour seals (P. vitulina) has a low prevalence and seldom causes severe health impacts. The seal louse (Echinophthirius horridus) is the assumed intermediate host for transmission of A. spirocauda filariae between seals, comprising a unique parasite assembly conveyed from the terrestrial ancestors of pinnipeds. Although grey seals (Halichoerus grypus) are infected by seal lice, heartworm infection was not verified. Analysing a longterm dataset compiled over decades (1996–2021) of health monitoring seals along the German coasts comprising post mortem investigations and archived parasites, 2 cases of A. spirocauda infected male grey seals were detected. Tentative morphological identification was confirmed with molecular tools by sequencing a section of mtDNA COI and comparing nucleotide data with available heartworm sequence. This is the first record of heartworm individuals collected from the heart of grey seals at necropsy. It remains puzzling why heartworm infection occur much less frequently in grey than in harbour seals, although both species use the same habitat, share mixed haul-outs and consume similar prey species. If transmission occurs directly via seal louse vectors on haul-outs, increasing seal populations in the North- and Baltic Sea could have density dependent effects on prevalence of heartworm and seal louse infections. It remains to be shown how species-specificity of filarial nematodes as well as immune system traits of grey seals influence infection patterns of A. spirocauda.
•First study on effects of clearance of ammunition dumped in large amounts into the sea during and after World War II.•Harbour porpoises highly endangered in the Baltic Seas.•Severe lesions due to ...blast trauma found in porpoises from the Baltic Sea.•Microfractures and discolation of middle ear bone due to blast trauma.•Environmental effects need to be managed at international level.
Harbour porpoises are under pressure from increasing human activities. This includes the detonation of ammunition that was dumped in large amounts into the sea during and after World War II. In this context, forty-two British ground mines from World War II were cleared by means of blasting in the period from 28 to 31 August 2019 by a NATO unit in the German Exclusive Economic Zone within the marine protected area of Fehmarn Belt in the Baltic Sea, Germany. Between September and November 2019, 24 harbour porpoises were found dead in the period after those clearing events along the coastline of the federal state of Schleswig-Holstein and were investigated for direct and indirect effects of blast injury. Health evaluations were conducted including examinations of the brain, the air-filled (lungs and gastrointestinal tract) and acoustic organs (melon, acoustic fat in the lower jaw, ears and their surrounding tissues). The bone structure of the tympano-periotic complexes was examined using high-resolution peripheral quantitative computed tomography (HR-pQCT). In 8/24 harbour porpoises, microfractures of the malleus, dislocation of middle ear bones, bleeding, and haemorrhages in the melon, lower jaw and peribullar acoustic fat were detected, suggesting blast injury. In addition, one bycaught animal and another porpoise with signs of blunt force trauma also showed evidence of blast injury. The cause of death of the other 14 animals varied and remained unclear in two individuals. Due to the vulnerability and the conservation status of harbour porpoise populations in the Baltic Sea, noise mitigation measures must be improved to prevent any risk of injury. The data presented here highlight the importance of systematic investigations into the acute and chronic effects of blast and acoustic trauma in harbour porpoises, improving the understanding of underwater noise effects and herewith develop effective measures to protect the population level.
We recovered the first full-length poxvirus genome, including the terminal hairpin region, directly from complex clinical material using a combination of second generation short read and third ...generation nanopore sequencing technologies. The complete viral genome sequence was directly recovered from a skin lesion of a grey seal thereby preventing sequence changes due to in vitro passaging of the virus. Subsequent analysis of the proteins encoded by this virus identified genes specific for skin adaptation and pathogenesis of parapoxviruses. These data warrant the classification of seal parapoxvirus, tentatively designated SePPV, as a new species within the genus Parapoxvirus.
In a 1-year survey of wild terrestrial predators in northern Germany, we found that 5 of 110 foxes were infected with contemporary avian influenza A(H5N1) viruses, forming a temporal cluster during ...January‒March 2023. Encephalitis and strong cerebral virus replication but only sporadic mammalian-adaptive viral polymerase basic 2 protein E627K mutations were seen.
•We analyzed liver histology of 191 Baltic grey seals during 1981–2015.•Cell infiltrations were the most common finding.•Portal cell infiltrations decreased, whereas lipid granulomas increased over ...the study period.•Hepatic stellate cells showed a positive trend with PCB concentrations.
The liver plays an important role in the metabolism and elimination of endogenic and exogenic lipid-soluble compounds. Multiple studies have shown that polychlorinated biphenyls (PCB) and dichlorodiphenyl trichloroethane (DDT) lead to morphological changes in liver cells. The aim of the present study was therefore to analyse liver changes over time in Baltic grey seals (Halichoerus grypus) and to correlate these with historical PCB and DDT contaminations. A total of 191 liver samples were collected between 1981 and 2015 in the Gulf of Bothnia and northern Baltic Proper. Six histological features were evaluated, including portal mononuclear cell infiltration, random mononuclear cell infiltration, lipid granulomas, hepatocellular fat vacuoles, hepatic stellate cells and mild multifocal bile duct hyperplasia accompanied by portal fibrosis. Three of the six lesions showed a significant correlation with age. Furthermore, a positive correlation between portal mononuclear cell infiltration and mild multifocal bile duct hyperplasia was found. Additionally, lipid granulomas were significantly correlated with hepatic stellate cells. More importantly, hepatic stellate cells and mild multifocal bile duct hyperplasia were correlated with adipose tissue (blubber) concentrations of ƩPCB, measured in a subsample (n = 34) of all individuals. No correlation with lesions and ƩDDT concentrations were found. These results show that age is an important factor for the development of these liver lesions, but PCBs burden may be an influencing factor. This is in agreement with previous studies of marine mammals in the Baltic Sea as well as in the Arctic. We therefore conclude that not only age of the animals, but also exposure to PCBs should be taken into account when understanding and evaluating the current health status of Baltic grey seals.
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