Myxosporeans and Myxosporidiosis of allogenetic gibel carp (Carassius auratus gibelio Bloch) in China
Zhang Jinyong*1, Liu Xinhua1, Xi Bingwen2
1Fish Diseases Laboratory, State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, China
2Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, 214081 Wuxi, China
Allogynogeneticgibel carp, Carassiusauratusgibelio (Bloch) has been becoming one of themost popular freshwater cultured species with commercially importancein the mainland of China since it was selectively bred by its special dual reproduction modes of gynogenesis and syngenesis in the early 1980s. With the improvement of intensiveaquaculture techniques and production of a new variety, designated as the allogynogeneticgibel carp “CAS III”, this species has been widely extended for culture into many freshwater wetlands and the annual production capacity was up to 2 million tons in 2011 in China. Meanwhile, accompanied with the rapid development of allogynogeneticgibel carp aquaculture industry, more and more pathogenic organisms have been found to cause morbidity, mortality and severe economic losses. Among them, myxozoans represent an important group of pathogenic parasite. To get the information of myxosporean diversity and epidemiology of myxosporidiosisof allogynogeneticgibel carp in China, an intensive parasitological investigation have been conducted from 2010 to 2014. More than 40 myxosporean species have been found, among thenThelohanelluswuhanensis, T. wangi, T.testudineus, M. honghuensis, M. turpisrotundusand M. wulii caused severe myxosporidiosis which caused severe economic losses to impede the sustainable development of allogynogeneticgibel carp culture industry. Molecular epidemiological investigation indicated that different myxosporean species of this gibel carp represent variable infection patterns and dynamic distribution in water column, sediment and fish host. Most importantly, some myxosporeans have spilled over from culture pond to wild watershed. The histopathological responses of fish to these hitozoticmyxosporeans and their phylogenetic relationship, life cycle and epidemiology were also investigated and analyzed.
Acknowledgements: NaturalSciencesFoundation of JiangsuProvince (No. BK2012240) and theNaturalSciencesFoundation of China (No.31101623, 31411130791, 31472296).