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1.
Marine turtle fibropapillomatosis (FP) is a devastating neoplastic disease characterized by single or multiple cutaneous and visceral fibrovascular tumors. Chelonid alphaherpesvirus 5 (ChHV5) has been identified as the most likely etiologic agent. From 2010 to 2013, the presence of ChHV5 DNA was determined in apparently normal skin, tumors and swab samples (ocular, nasal and cloacal) collected from 114 olive ridley ( Lepidochelys olivacea) and 101 green ( Chelonia mydas) turtles, with and without FP tumors, on the Pacific coasts of Costa Rica and Nicaragua. For nesting olive ridley turtles from Costa Rica without FP, 13.5% were found to be positive for ChHV5 DNA in at least one sample, while in Nicaragua, all olive ridley turtles had FP tumors, and 77.5% tested positive for ChHV5 DNA. For green turtles without FP, 19.8% were found to be positive for ChHV5 DNA in at least one of the samples. In turtles without FP tumors, ChHV5 DNA was detected more readily in skin biopsies than swabs. Juvenile green turtles caught at the foraging site had a higher prevalence of ChHV5 DNA than adults. The presence of ChHV5 DNA in swabs suggests a possible route of viral transmission through viral secretion and excretion via corporal fluids. 相似文献
2.
Past studies of free-ranging green turtles Chelonia mydas with fibropapillomatosis (FP) in Hawaii have shown that animals become immunosuppressed with increasing severity of this disease. Additionally, preliminary clinical examination of moribund turtles with FP revealed that some animals were also bacteraemic. We tested the hypothesis that bacteraemia in sea turtles is associated with the severity of FP. We captured free-ranging green turtles from areas in Hawaii where FP is absent, and areas where FP has been endemic since the late 1950s. Each turtle was given an FP severity score ranging from 0 (no tumours) to 3 (severely affected). A fifth category included turtles that were stranded ashore and moribund with FP. We found that the percentage of turtles with bacteraemia increased with the severity of FP, and that the majority of bacteria cultured were Vibrio spp. Turtles with severe FP were more susceptible to bactaeremia, probably in part due to immunosuppression. The pattern of bacteraemia in relation to severity of disease strengthens the hypothesis that immunosuppression is a sequel to FP. 相似文献
3.
Sea turtle fibropapillomatosis (FP) is a disease marked by proliferation of benign but debilitating cutaneous fibropapillomas and occasional visceral fibromas. Transmission experiments have implicated a chloroform-sensitive transforming agent present in filtered cell-free tumor homogenates in the etiology of FP. In this study, consensus primer PCR methodology was used to test the association of a chelonian herpesvirus with fibropapillomatosis. Fibropapilloma and skin samples were obtained from 17 green and 2 loggerhead turtles affected with FP stranded along the Florida coastline. Ninety-three cutaneous and visceral tumors from the 19 turtles, and 33 skin samples from 16 of the turtles, were tested. All turtles affected with FP had herpesvirus associated with their tumors as detected by PCR. Ninety-six percent (89/93) of the tumors, but only 9% (3/33) of the skin samples, from affected turtles contained detectable herpesvirus. The skin samples that contained herpesvirus were all within 2 cm of a fibropapilloma. Also, 1 of 11 scar tissue samples from sites where fibropapillomas had been removed 2 to 51 wk earlier from 5 green turtles contained detectable herpesvirus. None of 18 normal skin samples from 2 green and 2 loggerhead turtles stranded without FP contained herpesvirus. The data indicated that herpesvirus was detectable only within or close to tumors. To determine if the same virus infected both turtle species, partial nucleotide sequences of the herpesvirus DNA polymerase gene were determined from 6 loggerhead and 2 green turtle samples. The sequences predicted that herpesvirus of loggerhead turtles differed from those of green turtles by only 1 of 60 amino acids in the sequence examined, indicating that a chelonian herpesvirus exhibiting minor intratypic variation was the only herpesvirus present in tumors of both green and loggerhead turtles. The FP-associated herpesvirus resisted cultivation on chelonian cell lines which support the replication of other chelonian herpesviruses. These results lead to the conclusion that a chelonian herpesvirus is regularly associated with fibropapillomatosis and is not merely an incidental finding in affected turtles. 相似文献
4.
We examined data collected by the US Sea Turtle Stranding and Salvage Network on 4,328 green turtles (Chelonia mydas) found dead or debilitated (i.e., stranded) in the eastern half of the USA from Massachusetts to Texas during the period extending from 1980 to 1998. Fibropapillomatosis (FP) was reported only on green turtles in the southern half of Florida (south of 29 degrees N latitude). Within this region, 22.6% (682/3,016) of the turtles had tumors. Fibropapillomatosis was more prevalent in turtles found along the western (Gulf) coast of Florida (51.9%) than in turtles found along the eastern (Atlantic) coast of Florida (11.9%) and was more prevalent in turtles found in inshore areas (38.9%) than in turtles found in offshore areas (14.6%). A high prevalence of FP corresponded to coastal waters characterized by habitat degradation and pollution, a large extent of shallow-water area, and low wave energy, supporting speculation that one or more of these factors could serve as an environmental cofactor in the expression of FP. A high prevalence of FP did not correspond to high-density green turtle assemblages. Turtles with tumors were found most commonly during the fall and winter months, and the occurrence of tumors was most common in turtles of intermediate size (40-70-cm curved carapace length). Stranded green turtles with tumors were more likely to be emaciated or entangled in fishing line and less likely to have propeller wounds than were stranded green turtles without tumors. Turtles with and without tumors were equally likely to show evidence of a shark attack. The percent occurrence of tumors in stranded green turtles increased from approximately 10% in the early 1980s to over 30% in the late 1990s. Fibropapillomatosis was first documented in southernmost Florida in the late 1930s and spread throughout the southern half of Florida and the Caribbean during the mid-1980s. Because green turtles living in south Florida are known to move throughout much of the Caribbean, but are not known to move to other parts of the USA or to Bermuda, the spread and current distribution of FP in the western Atlantic, Gulf of Mexico, and Caribbean can be explained by assuming FP is caused by an infectious agent that first appeared in southern Florida. Aberrant movements of captive-reared turtles or of turtles that are released into areas where they were not originally found could spread FP beyond its current distribution. 相似文献
5.
The relationship between hematologic status and severity of tumor affliction in green turtles (Chelonia mydas) with fibropapillomatosis (FP) was examined. During 1 wk periods in July 1997 and July 1998, we bled 108 free-ranging green turtles from Pala'au (Molokai, Hawaii, USA) where FP is endemic. Blood was analyzed for hematocrit, estimated total solids, total white blood cell (WBC) count and differential WBC count. Each turtle was assigned a subjective tumor score ranging from 0 (no visible external tumors) to 3 (heavily tumored) that indicated the severity of FP. There was a progressive increase in monocytes and a decrease in all other hematologic parameters except heterophils and total numbers of white blood cells as tumor score increased. These data indicate that tumor score can relate to physiologic status of green turtles afflicted with FP, and that tumor score is a useful field monitor of severity of FP in this species. 相似文献
6.
Fibropapillomatosis (FP) threatens the survival of green turtle (Chelonia mydas) populations at a global scale, and human activities are regularly pointed as causes of high FP prevalence. However, the association of ecological factors with the disease’s severity in complex coastal systems has not been well established and requires further studies. Based on a set of 405 individuals caught over ten years, this preliminary study provides the first insight of FP in Martinique Island, which is a critical development area for immature green turtles. Our main results are: (i) 12.8% of the individuals were affected by FP, (ii) FP has different prevalence and temporal evolution between very close sites, (iii) green turtles are more frequently affected on the upper body part such as eyes (41.4%), fore flippers (21.9%), and the neck (9.4%), and (iv) high densities of individuals are observed on restricted areas. We hypothesise that turtle’s aggregation enhances horizontal transmission of the disease. FP could represent a risk for immature green turtles’ survival in the French West Indies, a critical development area, which replenishes the entire Atlantic population. Continuing scientific monitoring is required to identify which factors are implicated in this panzootic disease and ensure the conservation of the green turtle at an international scale. 相似文献
7.
A recently developed enzyme-linked immunosorbent assay (ELISA) was used to assess exposure of Florida wild green turtles Chelonia mydas to LETV, the herpesvirus associated with lung-eye-trachea disease (LETD). Plasma samples from 329 wild juvenile green turtles netted in the Indian River lagoon, along the Sebastian reef, or in the Trident basin (Indian River and Brevard Counties, Florida) were tested by ELISA for the presence of antibodies to LETV. Plasma samples from 180 wild juvenile green turtles were tested from these study sites to compare the prevalence of anti-LETV antibodies. While some plasma samples from each site contained anti-LETV antibodies (confirmed by Western blot analysis), plasma samples collected from the Indian River lagoon had statistically higher optical density values measured in the ELISA. No statistical differences were observed when these same plasma samples were analyzed for changes in the level of anti-LETV antibodies over 3 years (1997, 1998, and 1999). To explore the relationship between anti-LETV antibodies and fibropapillomatosis (FP), plasma from 133 green turtles scored for fibropapilloma tumor severity were tested by ELISA. There was no correlation between tumor severity and the presence of antibodies against LETV. Additional plasma samples collected from 16 tagged green turtles captured and sampled more than once (recaptures) were also tested to monitor antibody levels to LETV relative to the FP status of individual turtles over time. Again there was no clear relationship between FP tumor status and the presence of antibodies to LETV. Finally, ELISA tests on plasma from 13 nesting female turtles (9 green and 4 loggerhead) revealed high levels of anti-LETV antibodies in 11 individuals, including 2 loggerhead turtles. These results provide strong evidence that wild Florida green turtle populations at these 3 study sites are exposed to LETV or a closely related virus and that loggerhead turtles may be exposed as well. Based on a cutoff optical density value of 0.310, 71 out of the 329 wild Florida green turtles tested were seropositive for LETV antibodies (seroprevalence = 21.6%). In addition, no relationship between FP tumor severity or status and the presence of anti-LETV antibodies was found, further supporting the hypothesis that LETV and the FP-associated herpesvirus (FPHV) are separate infections of marine turtles. 相似文献
8.
Cell-mediated and humoral immune status of free-ranging green turtles (Chelonia mydas) in Hawaii (USA) with and without fibropapillornatosis (FP) were assessed. Tumored and non-tumored turtles from Kaneohe Bay (KB) on the island of Oahu and from FP-free areas on the west (Kona/Kohala) coast of the island of Hawaii were sampled from April 1998 through February 1999. Turtles on Oahu were grouped (0-3) for severity of tumors with 0 for absence of tumors, 1 for light, 2 for moderate, and 3 for most severe. Turtles were weighed, straight carapace length measured and the regression slope of weight to straight carapace length compared between groups (KB0, KB1, KB2, KB3, Kona). Blood was assayed for differential white blood cell count, hematocrit, in vitro peripheral blood mononuclear cell (PBMC) proliferation in the presence of concanavalin A (ConA) and phytohaemagglutinin (PHA), and protein electrophoresis. On Oahu, heterophil/lymphocyte ratio increased while eosinophil/monocyte ratio decreased with increasing tumors score. Peripheral blood mononuclear cell proliferation indices for ConA and PHA were significantly lower for turtles with tumor scores 2 and 3. Tumor score 3 turtles (KB3) had significantly lower hematocrit, total protein, alpha 1, alpha 2, and gamma globulins than the other four groups. No significant differences in immune status were seen between non-tumored (or KB1) turtles from Oahu and Hawaii. There was no significant difference between groups in regression slopes of body condition to carapace length. We conclude that turtles with severe FP are imunosuppressed. Furthermore, the lack of significant difference in immune status between non-tumored (and KB1) turtles from Oahu and Kona/Kohala indicates that immunosuppression may not be a prerequisite for development of FP. 相似文献
9.
We necropsied 255 stranded green turtles Chelonia mydas with fibropapillomatosis (FP) from the Hawaiian Islands, North Pacific, from August 1993 through May 2003. Of these, 214 (84 %) were euthanized due to advanced FP and the remainder were found dead in fresh condition. Turtles were assigned a standardized tumor severity score ranging from 1 (lightly tumored) to 3 (heavily tumored). Tumors were counted and measured and categorized as external, oral, or internal and tissues evaluated by light microscopy. Turtles in tumor score 2 and 3 categories predominated, and tumor score 3 turtles were significantly larger than the other 2 categories. More juveniles stranded than subadults or adults. Total cross-sectional area of tumors increased significantly with straight carapace length (SCL). Frequency distribution of total number of external tumors per turtle was significantly skewed to the right, and there were significantly more tumors at the front than rear of turtles. Eighty percent of turtles had oral tumors, and 51% of turtles with oral tumors had tumors in the glottis. Thirty-nine percent of turtles had internal tumors, most of them in the lung, kidney and heart. Fibromas predominated in lung, kidney and musculoskeletal system whereas myxofibromas were more common in intestines and spleen. Fibrosarcomas of low-grade malignancy were most frequent in the heart, and heart tumors had a predilection for the right atrium. Turtles with FP had significant additional complications including inflammation with vascular flukes, bacterial infections, poor body condition, and necrosis of salt gland. Turtles with oral tumors were more likely to have secondary complications such as pneumonia. Most turtles came from the island of Oahu (74%) followed by Maui (20 %), Hawaii, Molokai, and Lanai (<3 % each). On Oahu, significantly more turtles we necropsied stranded along the northwestern and northeastern shores. 相似文献
10.
Marine turtle fibropapillomatosis (FP) is a disease primarily affecting green turtles ( Chelonia mydas) that is characterized by multiple cutaneous masses. In addition, the condition has been confirmed in other species of sea turtles. The disease has a worldwide, circumtropical distribution and has been observed in all major oceans. Although reported since the late 1930s in Florida, it was not until the late 1980s that it reached epizootic proportions in several sea turtle populations. Long-term studies have shown that pelagic turtles recruiting to near shore environments are free of the disease. After exposure to these benthic ecosystems, FP manifests itself with primary growths in the corner of the eyes spreading to other epithelial tissue. One or more herpesviruses, a papillomavirus, and a retrovirus have been found associated with tumors using electron microscopy and molecular techniques; however, the primary etiological agent remains to be isolated and characterized. Field observations support that the prevalence of the disease is associated with heavily polluted coastal areas, areas of high human density, agricultural runoff, and/or biotoxin-producing algae. Marine turtles can serve as excellent sentinels of ecosystem health in these benthic environments. FP can possibly be used as an indicator but correlations with physical and chemical characteristics of water and other factors need to be made. Further research in identifying the etiologic agent and its association with other environmental variables can provide sufficient parameters to measure the health of coastal marine ecosystems, which serve not only as ecotourism spots but also as primary feeding areas for sea turtles. 相似文献
11.
Lyngbya majuscula, a benthic filamentous cyanobacterium found throughout tropical and subtropical oceans, has been shown to contain the tumour promoting compounds lyngbyatoxin A (LA) and debromoaplysiatoxin (DAT). It grows epiphytically on seagrass and macroalgae, which also form the basis of the diet of the herbivorous green turtle ( Chelonia mydas). This toxic cyanobacterium has been observed growing in regions where turtles suffer from fibropapillomatosis (FP), a potentially fatal neoplastic disease. The purpose of this study was to determine whether green turtles consume L. majuscula in Queensland, Australia and the Hawaiian Islands, USA, resulting in potential exposure to tumour promoting compounds produced by this cyanobacterium. L. majuscula was present, though not in bloom, at nine sites examined and LA and DAT were detected in variable concentrations both within and between sites. Although common in green turtle diets, L. majuscula was found to contribute less than 2% of total dietary intake, indicating that turtles may be exposed to low concentrations of tumour promoting compounds during non-bloom conditions. Tissue collected from dead green turtles in Moreton Bay tested positive for LA. An estimated dose, based on dietary intake and average toxin concentration at each site, showed a positive correlation for LA with the proportion of the population observed with external FP lesions. No such relationship was observed for DAT. This does not necessarily demonstrate a cause and effect relationship, but does suggest that naturally produced compounds should be considered in the aetiology of marine turtle FP. 相似文献
12.
Fibropapillomatosis (FP) of marine turtles is an emerging neoplastic disease associated with infection by a novel turtle herpesvirus, fibropapilloma-associated turtle herpesvirus (FPTHV). This report presents 23 kb of the genome of an FPTHV infecting a Hawaiian green turtle (Chelonia mydas). By sequence homology, the open reading frames in this contig correspond to herpes simplex virus genes UL23 through UL36. The order, orientation, and homology of these putative genes indicate that FPTHV is a member of the Alphaherpesvirinae. The UL27-, UL30-, and UL34-homologous open reading frames from FPTHVs infecting nine FP-affected marine turtles from seven geographic areas and three turtle species (C. mydas, Caretta caretta, and Lepidochelys olivacea) were compared. A high degree of nucleotide sequence conservation was found among these virus variants. However, geographic variations were also found: the FPTHVs examined here form four groups, corresponding to the Atlantic Ocean, West pacific, mid-Pacific, and east Pacific. Our results indicate that FPTHV was established in marine turtle populations prior to the emergence of FP as it is currently known. 相似文献
14.
Herpesviruses are associated with several diseases of marine turtles including lung-eye-trachea disease (LETD) and gray patch disease (GPD) of green turtles (Chelonia mydas) and fibropapillomatosis (FP) of green, loggerhead (Caretta caretta), and olive ridley turtles (Lepidochelys olivacea). The stability of chelonian herpesviruses in the marine environment, which may influence transmission, has not been previously studied. In these experiments, LETD-associated herpesvirus (LETV) was used as a model chelonian herpesvirus to test viral infectivity after exposure to seawater. The LETV virus preparations grown in terrapene heart (TH-1) cells were dialyzed for 24 to 120 hr against aerated artificial or natural seawater or Hank's balanced salt solution (HBBS). Fresh TH-1 cells were inoculated with dialyzed LETV, and on day 10 post-infection cells were scored for cytopathic effect. Virus samples dialyzed up to 120 hr were positive for the herpesvirus DNA polymerase gene by polymerase chain reaction. Electron microscopy revealed intact LETV nucleocapsids after exposure of LETV to artificial seawater or HBSS for 24 hr at 23 C. LETV preparations remained infectious as long as 120 hr in natural and artificial seawater at 23 C. Similar results were obtained with a second culturable chelonian herpesvirus, HV2245. LETV infectivity could not be detected after 48 hr exposure to artificial seawater at 30 C. Since LETV and HV2245 remain infectious for extended periods of time in the marine environment, it is possible that FP-associated and GPD-associated herpesviruses also may be stable. These findings are significant both for researchers studying the epidemiological association of herpesviruses with diseases of marine turtles and for individuals who handle turtles in marine turtle conservation efforts. 相似文献
15.
Abstract: To examine effects of relocation on eastern box turtles ( Terrapene carolina), we compared home ranges and movement patterns of 10 resident and 10 relocated box turtles in Davidson, North Carolina, USA. Home ranges of relocated turtles were approximately 3 times larger than those of resident turtles when measured by minimum convex polygons, 6 times larger than resident turtles when measured with 95% kernels and 7.5 times larger than resident turtles when measured by 50% kernels. Relocated turtles also moved a greater average distance per day than resident turtles. Additionally, 5 relocated turtles experienced mortality or disappearance compared to no mortality or disappearance of resident turtles. Our results raise questions about the success of relocation as a management strategy for eastern box turtles. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):772–777; 2008) 相似文献
17.
NADPH-cytochrome P-450 reductase (FP1) and NADH-cytochrome b5 reductase (FP2) involved in the microsomal fraction of rat liver have been modified chemically by periodate-oxidized NADP+ and NAD+ (o-NAD(P]. Despite its low Ki values (approximately 30 microM) o-NADP is not covalently bound with FP1, although o-NAD with Ki greater than 100 microM chemically modifies FP1 by suppressing its activity. The protective effect of NADP+ against FP1 inactivation indicates that FP1 is modified in the NADP+ binding site. An active centre of FP2 is modified by o-NAD in the same manner as FP1 (NAD+ prevents FP2 from inactivation). FP2 is slightly inactivated when the concentration of o-NADP is one order of magnitude higher than that of o-NAD. As found, the o-NAD-modified microsomal FP1 inhibits the oxidation of cytochrome P-450 substrates (acetanilide and p-nitroanisole). 相似文献
18.
- 1. 1. Sea turtles have a high fecundity, high mortality, great longevity life history strategy.
- 2. 2. With the exception of the leatherback, turtle distribution is constrained by the 20°C surface isotherm.
- 3. 3. All sea turtles exhibit temperature-dependent sex determination (TSD) with pivotal temperatures close to 29°C.
- 4. 4. It is suggested that hatchling sex ratio will vary chaotically because of TSD.
- 5. 5. Because of TSD and natal homing, sea turtles are likely to be adversely affected by global warming.
- 6. 6. TSD and global warming have implications for conservation/management of sea turtles.
相似文献
19.
HIV infection is initiated by the fusion of the viral membrane with the target T-cell membrane. The HIV envelope glycoprotein, gp41, contains a fusion peptide (FP) in the N terminus that functions together with other gp41 domains to fuse the virion with the host cell membrane. We recently reported that FP co-localizes with CD4 and T-cell receptor (TCR) molecules, co-precipitates with TCR, and inhibits antigen-specific T-cell proliferation and pro-inflammatory cytokine secretion. Molecular dynamic simulation implicated an interaction between an alpha-helical transmembrane domain (TM) of the TCRalpha chain (designated CP) and the beta-sheet 5-13 region of the 16 N-terminal amino acids of FP (FP(1-16)). To correlate between the theoretical prediction and experimental data, we synthesized a series of mutants derived from the interacting motif GALFLGFLG stretch (FP(5-13)) and investigated them structurally and functionally. The data reveal a direct correlation between the beta-sheet structure of FP(5-13) and its mutants and their ability to interact with CP and induce immunosuppressive activity; the phenylalanines play an important role. Furthermore, studies with fluorescently labeled peptides revealed that this interaction leads to penetration of the N terminus of FP and its active analogues into the hydrophobic core of the membrane. A detailed understanding of the molecular interactions mediating the immunosuppressive activity of the FP(5-13) motif should facilitate evaluating its contribution to HIV pathology and its exploitation as an immunotherapeutic tool. 相似文献
20.
The rich diversity of the world’s reptiles is at risk due to significant population declines of broad taxonomic and geographic scope. Significant factors attributed to these declines include habitat loss, pollution, unsustainable collection and infectious disease. To investigate the presence and significance of a potential pathogen on populations of critically endangered bog turtles ( Glyptemys muhlenbergii) as well sympatric endangered wood ( G. insculpta) and endangered spotted ( Clemmys guttata) turtles in the northeastern United States, choanal and cloacal swabs collected from 230 turtles from 19 sites in 5 states were screened for herpesvirus by polymerase chain reaction. We found a high incidence of herpesvirus infection in bog turtles (51.5%; 105/204) and smaller numbers of positive wood (5) and spotted (1) turtles. Sequence and phylogenetic analysis revealed three previously uncharacterized alphaherpesviruses. Glyptemys herpesvirus 1 was the predominant herpesvirus detected and was found exclusively in bog turtles in all states sampled. Glyptemys herpesvirus 2 was found only in wood turtles. Emydid herpesvirus 2 was found in a small number of bog turtles and a single spotted turtle from one state. Based on these findings, Glyptemys herpesvirus 1 appears to be a common infection in the study population, whereas Glyptemys herpesvirus 2 and Emydid herpesvirus 2 were not as frequently detected. Emydid herpesvirus 2 was the only virus detected in more than one species. Herpesviruses are most often associated with subclinical or mild infections in their natural hosts, and no sampled turtles showed overt signs of disease at sampling. However, infection of host-adapted viruses in closely related species can result in significant disease. The pathogenic potential of these viruses, particularly Emydid herpesvirus 2, in sympatric chelonians warrants additional study in order to better understand the relationship of these viruses with their endangered hosts. 相似文献
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