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61.
The spread of both infectious and noninfectious diseases through wildlife populations is of increasing concern. Neoplastic diseases are rarely associated with population-level impacts in wildlife; however, impacts on individual health can be severe and might reflect deteriorating environmental conditions. An adult male free-ranging Blanding’s turtle (Emydoidea blandingii) originally captured in 2005 and deemed healthy, was recaptured in 2018 with a 1 × 1.5 cm intra-oral broad-based right mandibular mass. An excisional biopsy was performed, and histopathology revealed squamous cell carcinoma (SCC). Consensus herpesvirus PCR identified a novel herpesvirus (proposed name Emydoidea herpesvirus 2 [EBHV-2]) within the tumor. EBHV-2 shares 85% sequence homology with Terrapene herpesvirus 2 (TerHV-2), a herpesvirus linked to fibropapillomas in eastern box turtles (Terrapene carolina carolina). Virus-associated fibropapillomas have been identified in multiple marine turtle species and have had debilitating effects on their populations, but to date, virus-associated SCCs are rarely reported.  相似文献   
62.
A captive loggerhead turtle (Caretta caretta) of unknown sex, 3 years of age, presented with bilateral mucoid secretions, severe chemosis, conjunctival hyperemia, and globe retraction. The animal was evaluated ophthalmologically and systemically, and hematological, microbiological, and conjunctival cytological and biopsy samples were collected for complementary diagnosis. The histopathological examination showed amphophilic intranuclear inclusions associated with severe inflammatory infiltrate. The diagnosis of Chelonid alphaherpesvirus 5 (ChAHV 5) was confirmed with end point PCR. Following systemic treatment with L‐lysine, acyclovir and vitamin A, the ocular signs resolved. No amphophilic intranuclear inclusions were seen in a follow‐up biopsy 5 months later, and there has been no recurrence of clinical ophthalmic signs during a 4‐year follow‐up. It is suggested that ChAHV 5 be considered as a differential diagnosis in captive marine turtles that present for conjunctival disease other than fibropapillomatosis.  相似文献   
63.
64.
The green sea turtle is one of the long-lived species that comprise the charismatic marine megafauna. The green turtle has a long history of human exploitation with some stocks extinct. Here we report on a 30-year study of the nesting abundance of the green turtle stock endemic to the Hawaiian Archipelago. We show that there has been a substantial long-term increase in abundance of this once seriously depleted stock following cessation of harvesting since the 1970s. This population increase has occurred in a far shorter period of time than previously thought possible. There was also a distinct 3-4 year periodicity in annual nesting abundance that might be a function of regional environmental stochasticity that synchronises breeding behaviour throughout the Archipelago. This is one of the few reliable long-term population abundance time series for a large long-lived marine species, which are needed for gaining insights into the recovery process of long-lived marine species and long-term ecological processes.  相似文献   
65.
The fundamental conservation focus for Hobe Sound National Wildlife Refuge (HSNWR), Florida is to provide protected nesting habitat for three threatened or endangered marine turtle species. Turtle nesting and hatching spans from early spring to fall each year. Left unchecked, nest predation by raccoons and armadillos would destroy most turtle nests. Predators are removed to protect nests, primarily with a one person-month contract using control specialists. We maximized the efficiency of predator removal by using a passive tracking index to: (1) optimize the timing and strategy for predator removal, (2) minimize labor by identifying areas where predator removal would have maximal effect, (3) examine beach invasion patterns of predators, (4) assess efficacy of removal efforts, (5) provide anticipatory information for future turtle nesting seasons, and (6) serve as a detection method for invasion by additional species known to depredate turtle nests. An overall nest predation rate of 28% resulted, whereas the rate for the previous year was 42% when the same level of contracted predator removal was applied, but without monitoring predators. One year before that, predator removal was done without contracts with specialists and predation was 48%. Up to 95% of the nests were destroyed in the years prior to predator removal. Using 2000 data on numbers of nests, clutch sizes, and emergence rates, we estimated the number of hatchlings that would have been lost assuming that the predation rates observed from four predator removal scenarios at HSNWR would have occurred in 2000. Historical predation of 95% would have resulted in 120,597 hatchlings lost in 2000. Predator removal as part of regular refuge operations would have reduced this number to 62,481. Addition of a contract with control specialists would have further reduced the number lost to 53,778. Addition of temporal and spatial monitoring for predator removal reduced losses to 36,637.  相似文献   
66.
The distribution of glucagon-like peptide 1 (GLP-1)-positive cells in digestive tracts and pancreases of aquatic vertebrates was investigated by immunohistochemical staining method. The results suggested that GLP-1-positive cells were distributed in the columnar mucous epithelium and tubular glands of lamina propria in the digestive system. However, GLP-1-positive cells were also found in subepithelial lamina propria of the mucosae and muscularis in each segment of the digestive tract of Rana nigromaculata. The distribution densities of these cells reached peaks in the stomachs, and the middle or end segments of small intestines of Chinese softshell turtle, Bufo gargarizans, R. nigromaculata and catfish, and there was the third distribution density peak in the rectum of catfish. The total amount or overall density of GLP-1-positive cells varied a lot in the digestive tracts of different animal species. The distribution density was relatively low in the digestive tract of chub and reached the maximum in the digestive tracts of snakehead and catfish, but no GLP-1-positive cells were found in the digestive tract of bighead carp. GLP-1-positive cells were densely distributed in the pancreases of Chinese softshell turtle, B. gargarizans and R. nigromaculata. These cells spread over the superficial layers of islets or scattered in exocrine pancreas in the pancreas of B. gargarizans, spread in the endocrine cells or scattered in the pancreas of Chinese softshell turtle, scattered in the pancreas of R. nigromaculata and distributed in the superficial layers of islets in the pancreas of catfish.  相似文献   
67.
The black marsh turtle (Geoemydidae: Siebenrockiella crassicollis) is a freshwater turtle that occurs in equatorial tropical climates in South East Asia. The semen of S. crassicollis was investigated by electroejaculation. The spermatozoa of S. crassicollis are filiform in shape with curved heads. The entire length, midpiece to tail length, tail width and tail length of the spermatozoa were 71.33 ± 1.55 μm, 49.92 ± 1.13 μm, 0.43 ± 0.02 μm and 48.53 ± 0.25 μm, respectively. The head length, head width across the middle and head width across the base were 14.00 ± 0.38 μm, 0.79 ± 0.03 μm and 0.91 ±0.0.03 μm, respectively. The acrosomal region of the S. crassicollis spermatozoa was narrower than the head, with an acrosomal length and width at the annulus of 2.90 ± 0.13 μm and 0.43 ± 0.01 μm, respectively. The midpiece of the S. crassicollis spermatozoa was narrower than the head and contained 30–40 mitochondrial balls, each with a ball diameter of 0.16 ± 0.002 μm. The midpiece length, midpiece width and tail length were 4.92 ± 0.16, 0.78 ± 0.03 and 48.53 ± 0.25 μm, respectively. This study presents the characteristic appearance of a freshwater turtle spermatozoa in Southeast Asia, as observed under an electron microscope. The spermatozoa of Siebenrockiella crassicollis are morphologically different from those of other freshwater turtles from other regions described in previous studies.  相似文献   
68.
光合细菌对鳖的促长作用研究   总被引:1,自引:0,他引:1  
设3个饵料组,即添加光合细菌(PSB)的配合饵料组、不添加PSB的同一配方饵料组、全动物性饵料组,均放养规格213~220g的鳖种,在水温30±1℃的池内,经90天的养殖对比.以添加PSB配饵组生长最快,平均每只鳖日增重4.75g,日增重率为1.47%。证明投喂添加PSB配饵对养鳖有明显促长作用。  相似文献   
69.
鳖病防治中的科学用药   总被引:2,自引:0,他引:2  
在我国的鳖养殖生产中,用药方面还存在着某些问题。本文根据国内外对鳖用药物的研究、使用状况和我国目前鳖病用药的现状,提出了科学用药的一些见解。  相似文献   
70.
中华鳖稚鳖对几种药物敏感性的研究   总被引:7,自引:0,他引:7  
中华鳖稚鳖对几种常用药物的敏感性依次为:鳖康宁>高锰酸钾>孔雀绿>敌百虫>漂白粉>甲醛>硫酸铜>生石灰。根据本试验的结果,作者推荐了几种常用药物在鳖病防治中所使用的浓度  相似文献   
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