Rypien Krystal L, Baker David M
Department of Ecology and Evolutionary Biology, Dale R. Corson Hall, Cornell University, Ithaca, New York 14853, USA.
Dis Aquat Organ. 2009 Sep 7;86(1):1-7. doi: 10.3354/dao02106.
Vectors play a critical role in the ecology of infectious disease by facilitating between host transmission, emphasizing the multi-species nature of disease. Corals are suffering an onslaught of infectious diseases, yet we know little about the role of vector species in the ecology of these epizootics. The infection of octocorals by the fungus Aspergillus sydowii is a widespread Caribbean coral disease. The snail Cyphoma gibbosum is a likely vector species because it is a specialist predator of octocorals, moves regularly among coral colonies, and aggregates on diseased corals. We used a novel application of stable isotope techniques and antifungal-resistant strains of A. sydowii to identify the potential for this snail to vector disease. The use of both isotopically labeled and hygromycin-resistant fungus was successful in definitively tracing A. sydowii through the guts of C. gibbosum from ingestion to feces. Further, we demonstrated in laboratory experiments that snails fed antifungal-resistant A. sydowii excrete viable spores and hyphae in their feces. Overall, this study demonstrates the usefulness of isotopic labeling and antifungal-resistant fungi to trace the movement of pathogen propagules in microbially diverse environments, and suggests that C. gibbosum may be able to spread aspergillosis between octocoral hosts.
病原体载体在传染病生态学中起着关键作用，它促进了宿主间的传播，凸显了疾病的多物种特性。珊瑚正遭受传染病的侵袭，但我们对病原体载体物种在这些动物流行病生态学中的作用知之甚少。八放珊瑚被烟曲霉感染是加勒比地区一种广泛传播的珊瑚疾病。驼背榧螺是一种可能的病原体载体物种，因为它是八放珊瑚的专性捕食者，经常在珊瑚群体间移动，并聚集在患病珊瑚上。我们采用稳定同位素技术的新应用以及烟曲霉的抗真菌菌株，来确定这种蜗牛传播疾病的可能性。使用同位素标记和潮霉素抗性真菌成功地明确追踪了烟曲霉在驼背榧螺肠道内从摄入到粪便排出的过程。此外，我们在实验室实验中证明，喂食抗真菌烟曲霉的蜗牛在粪便中排出了有活力的孢子和菌丝。总体而言，本研究证明了同位素标记和抗真菌真菌在追踪微生物多样环境中病原体繁殖体移动方面的有用性，并表明驼背榧螺可能能够在八放珊瑚宿主之间传播曲霉病。
