Wirth Wytamma, Elliott Elizabeth, Rudd Donna, Hayes Linda, Maclaine Alicia, Mashkour Narges, Ahasan Shamim, Gorm Dahl Jakob, Drane Kezia, Ariel Ellen
College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD, Australia.
AusPhage, Rasmussen, QLD, Australia.
Front Vet Sci. 2020 Jan 31;7:33. doi: 10.3389/fvets.2020.00033. eCollection 2020.
Freshwater turtles inhabit most rivers and creeks on the east coast of Australia, but some species are only found in specific catchments, which makes them vulnerable to extinction. During annual fieldtrips to Alligator Creek, North Queensland, the resident population of and in a natural pond, just outside Bowling Green National Park, have been surveyed for a number of years and demographic data recorded against tagged turtles. Rounded, cutaneous lesions on individual animals were first noted in August 2016, three years after the first survey of the population. Turtles living in the upstream sections of the creek were not affected. An initial investigation into the cause of the lesions ruled out pollutants and although the bacterial communities appeared to be different on turtles with lesions, a causative agent was not identified. Attempts to isolate virus in culture was not successful and specific PCRs for ranavirus, papillomavirus, adenovirus and herpesvirus did not identify their presence. Blood biochemical parameters, body condition and activity levels were not significantly different between affected turtles and those without lesions. The turtles in this pond were monitored regularly over the following three years with 249 and 192 captured, tagged and released. The prevalence of the lesions fluctuated with season from 0 to 77 and 68% respectively, but did not vary significantly between species or sex in adults. There was a tendency for larger animals to be more likely to have lesions. The position of the lesions on the turtles was mostly on dorsal surfaces, distally on the legs and proximal on the tales of males, indicating that the initial lesion may have been associated with a behaviourally induced trauma. Recaptured animals ( = 43) during this period, provided records of lesion progression over time and while some healed up between capture events, others persisted for up to 24 months. Some turtles were repeatedly captured without lesions. Intra-species aggression associated with seasonal behaviours could potentially be the primary cause of skin trauma, followed by a secondary invasion of an unusual pathogen present in the environment.
淡水龟栖息于澳大利亚东海岸的大多数河流和小溪中，但有些物种仅在特定集水区被发现，这使它们极易灭绝。在每年前往北昆士兰鳄鱼溪的实地考察中，多年来一直在对鲍灵格林国家公园外一个天然池塘中的[两种龟的名称]的常驻种群进行调查，并针对标记的龟记录了种群统计学数据。2016年8月，即在对该种群首次调查三年后，首次注意到个别动物身上出现圆形皮肤病变。生活在溪流上游区域的龟未受影响。对病变原因的初步调查排除了污染物，尽管病变龟身上的细菌群落似乎有所不同，但未确定病原体。尝试在培养物中分离病毒未成功，针对蛙病毒、乳头瘤病毒、腺病毒和疱疹病毒的特异性聚合酶链反应也未检测到它们的存在。受影响的龟与未出现病变的龟之间的血液生化参数、身体状况和活动水平没有显著差异。在接下来的三年里，对这个池塘中的龟进行了定期监测，共捕获、标记并放生了249只[一种龟的名称]和192只[另一种龟的名称]。病变的患病率随季节波动，分别从0%到77%和68%，但在成年龟的物种或性别之间没有显著差异。体型较大的动物更有可能出现病变。龟身上病变的位置大多在背部，腿部远端以及雄性龟尾巴近端，这表明最初的病变可能与行为诱发的创伤有关。在此期间重新捕获的动物（n = 43）提供了病变随时间发展的记录，虽然有些在捕获事件之间愈合，但其他病变持续长达24个月。一些龟被反复捕获时没有病变。与季节性行为相关的种内攻击可能是皮肤创伤的主要原因，随后是环境中存在的一种不寻常病原体的二次入侵。
