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1.
Two morbilliviruses were isolated from carcases of Mediterranean monk seals (Monachus monachus) which had died in coastal areas of Greece and Mauritania. They were characterised as being closely related to the previously identified dolphin and porpoise morbilliviruses on the basis of their serological cross-reactivities in immunofluorescence assays, and sequence homologies in their N and P genes. The results suggest that morbilliviruses of aquatic mammals may cross barriers between species of different orders.  相似文献   

2.
Since 1988 morbilliviruses have been increasingly recognized and held responsible for mass mortality amongst harbour seals (Phoca vitulina) and other seal species. Virus isolations and characterization proved that morbilliviruses from seals in Northwest Europe were genetically distinct from other known members of this group including canine distemper virus (CDV), rinderpest virus, peste des petits ruminants virus and measles virus. An epidemic in Baikal seals in 1987 was apparently caused by a morbillivirus closely related to CDV so that two morbilliviruses have now been identified in two geographically distant seal populations, with only the group of isolates from Northwest Europe forming a new member of the genus morbillivirus: phocid distemper virus (PDV). Because of distemper-like disease, the Baikal seal morbillivirus was tentatively named PDV-2 in spite of its possible identity with CDV. The appearance of morbilliviruses in the Mediterranean Sea causing high mortality amongst dolphins should further increase the research activities on protection strategies for endangered species of marine mammals.  相似文献   

3.
Monoclonal antibodies (MAbs) were obtained using a purified preparation of the RBOK strain of a rinderpest vaccine virus. The cytoplasmic immunofluorescent staining test showed that these clones had specificity for the nucleoprotein (N) of the virus. Six clones which immunoprecipitated the N protein corroborated these results. Thirteen anti-N MAbs were used to compare geographically widespread rinderpest viruses (RPV) and peste des petits ruminants viruses (PPRV) to two other morbilliviruses, measles (MV) and canine distemper (CDV). The N protein antigen profiles of the 23 isolates determined by immunofluorescent staining and enzyme linked immunosorbent assay (ELISA) on infected cells enabled us to classify the strains into groups. A differential identification of the morbilliviruses can be made using one MAb or associations of the MAbs. The potential to distinguish between RPV and PPRV and between virulent and avirulent strains of rinderpest is of primary interest.  相似文献   

4.
The nucleotide sequences of the phosphoprotein (P) gene of peste des petits ruminants (PPRV) vaccine virus (PPRV Sungri/96) belongs to Asian lineage have been determined and the deduced amino acid sequences were compared with another vaccine strain PPRV/Nigeria75/1 and with those of the other morbilliviruses. The 1652 nucleotides of the P gene encode a phosphoprotein of 509 amino acid residues (from nucleotide numbers 60 to 1587), which is 91% identical to that of PPRV/Nigeria75/1. The C protein consists of 177 amino acid residues and is 91% identical with that of PPRV/Nigeria75/1. The conserved mRNA editing site (5'TTAAAAGGGCACAG) was present at positions 742-756 in the P gene, which is conserved in all other morbilliviruses. The CTT trinucleotide sequence is present at the N/P and P/M intergenic region, which is totally conserved in morbilliviruses. This will be the third sequence for the P gene of PPRV since that of the vaccine strain and a wild-type Turkish isolate has been published already.  相似文献   

5.
The complete nucleotide sequence of the nucleocapsid (N) protein of the peste-des-petits ruminants vaccine virus (PPRV Sungri/96) belonging to the Asian lineage was determined. The gene was 1692 nucleotides in length and encoded a polypeptide of 525 amino acids. The PPRV Sungri/96 N gene has a nucleotide homology of 92% for PPRV Nigeria 75/1 to 55.5% for canine distemper virus. At amino acid level the homology was 94.1% with PPRV Nigeria 75/1, while with other morbilliviruses, PPRV Sungri/96 had only 71.4–64.9% amino acid identity. The phosphorylation prediction reveals eight conserved sites across morbilliviruses, whereas in the C-terminal portion of the protein the sites are not conserved. Phylogenetic analysis of different N proteins of morbilliviruses revealed five well-defined clusters as observed previously. To the best of our knowledge this is the first report describing the nucleocapsid gene sequence of PPRV Indian isolate. Muthuchelvan, D., Sanyal, A., Balamurugan,V., Dhar, P. and Bandyopadhyay, S.K., 2006. Sequence analysis of the nucleoprotein gene of Asian lineage peste des petits ruminants vaccine virus.Veterinary Research Communications, 30(8), 957–963  相似文献   

6.
This work aimed at applying geometric morphometric analysis techniques to the skull of the Mediterranean monk seal ( Monachus monachus , Hermann, 1779). Inferential analyses were performed using a non-parameteric permutation framework based on a series of skulls of different age classes belonging to individuals of both sexes. Our goal was to establish whether a statistical approach based on osteometric measurements and surface analysis of photographs of the left lateral plane of the skull may lead to a different and scientifically sound method of age and sex classification in this critically endangered marine mammal. Our data indicate that non-parametric combination methodology enables the researcher to give local assessment using a combination with domains. Developing geometric morphometric techniques in a non-parametric permutation framework could be useful in solving high dimensional and small sample size problems as well as classification problems, including zoological classification of specimens within a specific population. The Mediterranean monk seal is believed to be the world's rarest pinniped and one of the most endangered mammals of the world, with fewer than 600 individuals currently surviving. The use of shape analysis would allow new insights into the biological characteristics of the monk seal by simply extracting potentially new information on age and size from museal specimens.  相似文献   

7.
Outbreaks of a canine distemper-like acute disease brought high mortalities to seal populations in north-west Europe and Lake Baikal from late 1987 to 1988. During these outbreaks three seals which were introduced from Lake Baikal to an aquarium in Japan developed a distemper-like disease and other seals raised in the same room were similarly affected. Clinical signs of dead seals were anorexia, diphasic fever, dyspnea, and neuromuscular tics. Characteristic microscopic lesions of acute interstitial pneumonia seen in the lung were accompanied with hyperplasia and syncytial giant cell formation of type II pneumocytes. Eosinophilic intranuclear and cytoplasmic inclusion bodies were present in bronchial epithelial cells, type II pneumocytes, epithelial cells of bile ducts and interlobular ducts of pancreas, transitional epithelium of renal pelvis, and reticular cells of lymph nodes. Ultrastructure of inclusion bodies was similar to that seen in cells infected with morbilliviruses. Serum samples from recovered seals had virus-neutralization antibodies against canine distemper virus. The present cases were the first report of morbillivirus infection of aquarium seals in Japan.  相似文献   

8.
Recently the isolation and characterisation of a morbillivirus which caused high mortality in common seals (Phoca vitulina) in 1988 have been reported. Because of the clinical and pathological similarity of the disease in seals to that of distemper in dogs, the name phocine distemper virus (PDV) has been proposed. There are marked differences in the virus-induced proteins of PDV compared to other morbilliviruses and the humoral immune response of moribund and dead seals to PDV was restricted to some of the internal antigens of PDV, similar to the response described earlier for canine distemper virus infection in dogs.  相似文献   

9.
A review of the 1988 European seal morbillivirus epizootic   总被引：2，自引：0，他引：2  
An epizootic of morbillivirus infection killed thousands of common seals (Phoca vitulina) in European seas in 1988. Most of the affected seals had respiratory signs and the main post mortem finding was acute pneumonia. The histopathological changes were similar to those of canine distemper. Six common porpoises (Phocoena phocoena) found stranded on the coast of Northern Ireland in late 1988 had similar lesions. Morbillivirus infection also killed several thousand Siberian seals (Phoca siberica) in Lake Baikal in 1987 and 1988. A morbillivirus (phocine distemper virus) has been isolated from affected seals in several European countries and studies of the antigenicity of the virus indicate that it has several unique epitopes that distinguish it from the other known morbilliviruses. Biochemical studies of the viral proteins, RNA and nucleotide sequence confirm that it is a new morbillivirus. There is seroepizootiological evidence of morbillivirus infection in Greenland harp seals (Pagophilus groenlandicus), ringed seals (Phoca hispida) and Dutch common seals several years before the 1988 epizootic. Antibodies to a morbillivirus have also been found in bottlenose dolphins (Tursiops truncatus) from the eastern coast of the USA. Further studies are required to determine whether these sea mammal populations have been infected with phocine distemper virus.  相似文献   

10.
To evaluate potential factors related to avian atherosclerosis, plasma cholesterol and triglyceride values were measured in 35 apparently healthy captive monk parakeets (Myiopsitta monachus). Birds were categorized as healthy or at risk based on body condition score and weight and were also evaluated based on their aviary environmental conditions. Plasma cholesterol mean was 8.008 mmol/L (range: 4.655 to 20.33 mmol/L) or 309.65 mg/dl (range: 180 to 786 mg/dl) for all birds sampled. Plasma triglyceride mean for all birds sampled was 4.364 mmol/L (range: 0.960 to 44.62 mmol/L) or 386.54 mg/dl (range: 85 to 3952 mg/dl). Thirty plasma samples were evaluated through density gradient ultracentrifugation lipid profiling techniques used to examine risk of cardiovascular disease in humans. The resultant lipid density profile graph was determined from the hydrated densities of the following lipids: triglyceride-rich lipoproteins, low-density lipoproteins (LDL) and subfractions, and high-density lipoproteins and subfractions. When analyzed using linear discriminant analysis, lipid profiles of triglyceride-rich lipoproteins, LDL1, LDL2, and high-density lipoprotein 2b subfractions were increased (P < 0.05) in at-risk monk parakeets when compared with healthy cohorts. Gender and diet had no apparent effect on plasma cholesterol or triglyceride concentrations. Cholesterol and triglyceride concentrations and lipoprotein density profiles from captive monk parakeets, a species known to be affected by atherosclerosis, may prove useful as markers for use in future investigation of atherosclerosis in birds. However, the consequence of increased plasma lipid concentrations and changes of lipoprotein profiles on avian health requires additional investigation.  相似文献   

11.
Morbillivirus group: genome organisation and proteins   总被引：1，自引：0，他引：1  
The Paramyxoviridae family is divided into three genera: Paramyxovirus, Pneumovirus and Morbillivirus. In the last group, there are four closely related viruses which are seriously pathogenic for man and animals, and usually cause acute diseases. At least two of them (measles and canine distemper viruses) can cause a persistent infection which leads to a chronic disease of the nervous system that, in the end, is fatal. For a long time, the biochemical analysis of morbilliviruses was hampered by the high susceptibility of some of their proteins to proteolysis. With cloning and sequencing technology, more data on the biology of those viruses are now available.  相似文献   

12.
Since 1987, at least eight morbillivirus infection (MI) epidemics have caused mass mortality of several free-living pinniped and cetacean populations around the world. The responsible agents, all belonging to the genus Morbillivirus (family Paramyxoviridae), have been characterized as either "canine distemper virus" strains, infecting pinnipeds, or as three new morbilliviruses, namely "phocid (phocine) distemper virus" , "porpoise morbillivirus" and "dolphin morbillivirus" . The last two agents are currently gathered under the common denomination of "cetacean morbillivirus". At post-mortem examination, a commonly occurring macroscopic lesion is represented by more or less severe bilateral pneumonia, with consolidation, congestion and oedema of both lungs, which fail to collapse. Histologically, a non-suppurative broncho-interstitial pneumonia, characterized by type II pneumocyte hyperplasia and by formation of endobronchial, endobronchiolar and endoalveolar "Warthin-Finkeldey type" syncytia, as well as a multifocal, non-suppurative encephalitis, associated with a severe and generalized lymphoid tissue depletion, are common pathological findings. Furthermore, eosinophilic viral inclusions are often detected, at both the intracytoplasmic and intranuclear level, within bronchial and bronchiolar epithelial, pulmonary syncytial, neuronal and other cell types. These inclusions, along with lymphoid and other cellular elements, are often found to be immunohistochemically positive for morbillivirus antigen. Among the still debated, or even controversial issues regarding MI in sea mammals, the one related to the origin of their causative agents is of particular concern. Another intriguing issue regards the synergistic effects, if any, associated with chronic exposure to a number of environmental pollutants, such as organochlorines and heavy metals. In fact, it is also unknown whether and how these chemicals contribute towards modulating the pathogenic and pathogenetic activity primarily displayed by sea mammal morbilliviruses.  相似文献   

13.
米非司酮对早孕猕猴孕酮和雌二醇分泌的研究   总被引：1，自引：0，他引：1  
为开展生殖生物学研究工作提供理想的动物模型。进行了本项试验,分析了米非司酮(ＲＵ４８６)对猕猴妊娠早期血清中孕酮(Ｐ)和雌二醇(Ｅ２)的影响。结果表明,注射ＲＵ４８６－段时间内孕酮和雌二醇基本不交,但Ｅ２/Ｐ比值有所增加,说明米非司酮干扰内分泌激素之间的平衡,随着出血的发生,孕酮、雌二醇均显著下降。这种降低与出血的发生有着明确的先后关系,从而证实了激素的变化源于蜕膜受损。  相似文献   

14.
The nucleotide sequence of the matrixprotein (M) gene of the lapinized rinderpest virus (RPV-L) was determined. The full-length cDNA of the RPV-L M gene is composed of 1460 base pairs and is supposed to contain an open reading frame of 1005 nucleotides encoding on M protein of 335 amino acids. The homology of the predicted amino acid among congeneric morbilliviruses such as RPV Kabete 'O' strain (wild strain of RPV), RPV RBOK strain (vaccine strain of RPV for cattle), measles virus (MV), and canine distemper virus (CDV), is approximately 94%, 93%, 87% and 77%, respectively. In the present study, all coding regions of the RPV-L strain have been determined.  相似文献   

15.
The genus Morbillivirus is classified into the family Paramyxoviridae, and is composed of 6 members, namely measles virus (MV), rinderpest virus (RPV), peste-des-petits-ruminants virus (PPRV), canine distemper virus (CDV), phocine distemper virus (PDV) and cetacean morbillivirus (CeMV). The MV, RPV, PPRV and CDV have been successfully attenuated through their serial passages in vitro for the production of live vaccines. It has been demonstrated that the morbilliviral virulence in animals was progressively attenuated with their consecutive passages in vitro. However, only a few reports were involved in explanation of an attenuation-related mechanism on them until many years after the establishment of a quasispecies theory. RNA virus quasispecies arise from rapid evolution of viruses with high mutation rate during genomic replication, and play an important role in gradual loss of viral virulence by serial passages. Here, we overviewed the development of live-attenuated vaccine strains against morbilliviruses by consecutive passages in vitro, and further discussed a related mechanism concerning the relationship between virulence attenuation and viral evolution.  相似文献   

16.
Peste des petits ruminants (PPR) is an acute or subacute, highly contagious viral disease of small ruminants, characterized by fever, oculonasal discharges, stomatitis, diarrhoea and pneumonia. This disease is included in the OIE (Office International des Epizooties) list of notifiable terrestrial animal diseases. PPR was first described in the early 1940s in Côte d′Ivoire, and at present, PPR is mainly circulating in Western and Central Africa, the Arabian Peninsula and Southern Asia. Peste des petits ruminants virus (PPRV), the etiological agent of PPR, is classified into the genus Morbillivirus in the family Paramyxoviridae, as its biological and physicochemical features are closely related to the other morbilliviruses. The first homologous PPR vaccine was developed by an artificially attenuated PPRV, named as Nigeria 75/1, which has been widely used in the production of live attenuated vaccines to protect small ruminants. A new generation of PPR vaccine candidates can be genetically modified to differentiate infected from vaccinated animals (DIVA), which nevertheless is difficult to achieve by conventional vaccines. In this review, we systematically discussed a broad range of vaccines against PPR, including commercially available vaccines and potential vaccine candidates, and further DIVA strategies for immunization with the new generation vaccines.  相似文献   

17.
Canine distemper virus (CDV) was previously considered to have a host range restricted to the canid family. In 1994, the virus was associated with sporadic outbreaks of distemper in captive felids. However, after severe mortality occurred in the Serengeti lions (Panthera leo), attention became focused on the pathogenesis of the virus and a concerted effort was made to identify the virus as CDV or a closely related feline morbillivirus. The present study was designed to explore the susceptibility of ferrets to challenge with two morbilliviruses isolated from lions and the protective effects of a modified-live mink distemper vaccine. Because mortality in ferrets infected with pathogenic CDV approaches 100%, the ferret was selected as a test animal. Two strains of lion morbillivirus were used as a challenge, A92-27/20 (California lion isolate) and A94-11/13 (Serengeti lion isolate). The two strains of lion morbillivirus were antigenically related to CDV (Rockborn strain), and ferrets were susceptible to both of the viruses when inoculated intraperitoneally. The inoculated ferrets were anorectic at 5-6 days postinoculation (PI), exhibited oculonasal discharge at 9-12 days PI, and became moribund at 12-22 days PI. Severe bilateral conjunctivitis was the typical clinical sign. Inclusion bodies characteristic of morbillivirus (eosinophilic, intranuclear, and intracytoplasmic) were distributed in many epithelial cells, including those of the skin, conjunctiva, gallbladder, liver, pancreas, stomach, trachea, lung, urinary bladder, and kidney. Virus was reisolated from selected lung tissues collected at necropsy and identified by CDV-specific immunofluorescence. Ferrets vaccinated with the mink distemper vaccine (Onderstepoort strain) were protected from challenge with the two lion strains, adding further support to the premise that the viruses are closely related to CDV.  相似文献   

18.
借助弗洛伊德的人格结构学说来解读《西游记》，发现在魔界、人界、天界三个圈层活动存在的唐僧、猪八戒、沙和尚三人分别是超我、本我、自我人格的典型；而孙悟空则是本我、自我、超我糅合在一起的典型。本文从魔性、人性、神性三个层面分析四种典型的人格，指出这四人是作者吴承恩精神世界、内心情感移植、外射到先存的历史、佛教故事人物之结果，《西游记》是作者“心灵游历”的外在体现。  相似文献   

19.
Even though breeding of companion birds has increased continuously for years, the fecundity assessment of birds has hardly been acknowledged. Knowledge of the structure of spermatozoa is crucial for evaluation of the basic reproductive biology of any species as well as for phylogenetic research and cladistic analyses of internal relationships. Spermatozoa of six different psittacine species (Nymphicus hollandicus, Myiopsitta monachus, Agapornis roseicollis, Melopsittacus undulatus, Tanygnathus lucionensis, Guarouba guarouba) were examined using light microscopy. Head length (nucleus including acrosome), head width, midpiece length and tail length were measured and documented. Significant differences were obvious among almost all of the species for almost all four parameters. However, in all the six species a significant moderate correlation between spermatozoa midpiece lengths and tail lengths (r = 0.535, p ≤ 0.01), spermatozoa head lengths and midpiece lengths (r = 0.508, p ≤ 0.01) as well as tail lengths (r = 0.472, p ≤ 0.01) was found. The present results confirm that spermatozoa of cockatiels have shorter heads and midpieces than the other psittacines examined in this study. Spermatozoa characteristics in the monk parakeet, blue‐naped parrrot and golden conure are previously unreleased and documented for the first time.  相似文献   

20.
1. The effects of taking a blood sample from one bird in a caged group on plasma concentrations of corticosterone and glucose in birds from its own group and birds from other groups were investigated. 2. Two blood sampling protocols were used: successive (all birds within a group were sampled one immediately after another) and alternative (birds from different groups were sampled one after another until all birds in all groups had been sampled). 3. Neither sampling protocol nor between or within group sampling rank was related to plasma concentrations of corticosterone and glucose. 4. The time taken to remove a blood sample (generally more than 45 s but less than 2 min) did not influence circulating corticosterone and glucose. 5. In individual birds plasma concentrations of corticosterone and glucose were poorly correlated with one another. 6. It is concluded that it is possible to take blood samples from a bird, kept in a group, without affecting plasma concentrations of corticosterone and glucose in other birds from that group or in birds from other groups in other cages.  相似文献   

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