Tomo Ikuko, Kemper Catherine M, Lavery Trish J
South Australian Museum, North Terrace, Adelaide, South Australia 5000, Australia.
J Wildl Dis. 2010 Apr;46(2):488-98. doi: 10.7589/0090-3558-46.2.488.
Between 1990 and 2007, carcasses of opportunistically collected short-beaked common dolphins (Delphinus delphis; n=238), Indo-Pacific bottlenose dolphins (Tursiops aduncus; n=167), and common bottlenose dolphins (Tursiops truncatus; n=15) were examined for parasites and life history data. Three species of lung nematodes (Halocercus lagenorhynchi, Stenurus ovatus, Pharurus alatus) were identified in surface nodules, subsurface lesions, or airways. Nematode burdens were light to heavy and, in many cases, would have compromised the dolphins' health. The number of dolphins infected was related to species, year, season, age class, and geographic region. Nematodes were found in all three species but were more prevalent in short-beaked common dolphins (mean annual prevalence=26%) than in bottlenose dolphins (12%). There was a significant increase in prevalence of nematodes in short-beaked common dolphins in 2005-06 (63%) compared to 1990-2004 (14%), with a peak in April-June. More young short-beaked common dolphins were infected than subadults and adults and, during the unusual infection event, there were more dependent calves (<130 cm) than juveniles. There were also more infections in dependent bottlenose dolphin (Tursiops spp.) calves but no increase in overall prevalence was detected during 2005-06. Because neonates of both short-beaked common dolphins and bottlenose dolphins were infected, mother-to-calf transmission is suspected for these species in South Australia. Numbers of infections in short-beaked common dolphins were higher in Gulf St Vincent than elsewhere in South Australia, particularly in 2005-06. The cause of the unusual infection event in short-beaked common dolphins is unknown. We discuss the influence of dolphin diet, life history, and external factors.
1990年至2007年间，对机会性收集的短吻真海豚（瓶鼻海豚属；n = 238）、印太瓶鼻海豚（宽吻海豚属；n = 167）和普通瓶鼻海豚（宽吻海豚属；n = 15）的尸体进行了寄生虫和生活史数据检查。在表面结节、皮下病变或气道中鉴定出三种肺线虫（拉氏嗜鲸线虫、卵形窄体线虫、翼形拟窄体线虫）。线虫感染程度从轻到重，在许多情况下，会损害海豚的健康。感染海豚的数量与物种、年份、季节、年龄组和地理区域有关。在所有三个物种中都发现了线虫，但在短吻真海豚中更为普遍（年平均患病率 = 26%），高于瓶鼻海豚（12%）。与1990年至2004年（14%）相比，2005 - 06年短吻真海豚中线虫患病率显著增加（63%），在4月至6月达到峰值。感染的年轻短吻真海豚比亚成体和成体更多，在异常感染事件期间，依赖期幼崽（<130厘米）比幼年期更多。依赖期瓶鼻海豚幼崽的感染也更多，但在2005 - 06年期间未检测到总体患病率增加。由于短吻真海豚和瓶鼻海豚的新生幼崽都被感染，怀疑在南澳大利亚这些物种存在母婴传播。短吻真海豚在圣文森特湾的感染数量高于南澳大利亚的其他地方，特别是在2005 - 06年。短吻真海豚异常感染事件的原因尚不清楚。我们讨论了海豚饮食、生活史和外部因素的影响。
