Effect of photoperiod change on chronobiology of cercarial emergence of Schistosoma japonicum derived from hilly and marshy regions of China.
The chronobiology of cercarial emergence appeared to be a genetically controlled behavior, adapted to definitive host species, for schistosome. However, a few physiological and ecological factors, for example the change of photoperiod, were reported to affect the rhythmic emergence of cercariae. Therefore, the effect of photoperiod change on cercarial emergence of two Schistosoma japonicum isolates, the hilly and the marshland, was investigated. Four shedding experiments each under a different photoperiod were conducted. Under a natural photoperiod, two distinct shedding modes, one from the hilly region and one from the marshland, were observed. Under a reversed photoperiod, the regular pattern (i.e. under a natural photoperiod) of S. japonicum cercarial emergence was reversed for the marshland isolate and disappeared for the hilly isolate. With an input of a 2 h darkness from 7am to 9am, the cercarial emergence peak were delayed for the two isolates; whereas with an input of a 2 h darkness from 5pm to 7pm, neither effect on the cercarial emergence rhythm was observed. The total cercariae emerged for both parasite isolates varied with a different photoperiod. The results indicate that the change of photoperiod could affect the chronobiology of S japonicum cercarial emergence.
Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China.
Su-Rong
SR
Wang
Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China; Department of Clinical Laboratory, The Central Hospital of Zaozhuang Mining Group, Qi Lianshan Road, Zaozhuang 277800, Shandong, China.
Yuan-Jian
YJ
Zhu
Department of Technology, Company of Zaozhuang Bayi Coal Water Mixture Thermoelectric, Taishan Road, Zaozhuang 277000, Shandong, China.
Qing-Peng
QP
Ge
Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China.
Meng-Jia
MJ
Yang
Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China.
Ji-Lei
JL
Huang
Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China.
Wen-Qiao
WQ
Huang
Department of Parasitology, School of Biology and Basic Medical Sciences, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China.
Hong-Xiang
HX
Zhuge
Department of Epidemiology and Statistics, School of Public Health, Soochow University, 199, Ren Ai Road, Suzhou 215123, Jiangsu, China. Electronic address: ludabing@suda.edu.cn.
Da-Bing
DB
Lu
D000818:Animals; D058487:Cercaria / Q000502:physiology; D002681:China; D002909:Chronobiology Phenomena / Q000502:physiology*; D017753:Ecosystem; D017440:Photoperiod; D012549:Schistosoma japonicum / Q000502:physiology*; D053833:Wetlands
Cercarial emergence; Chronobiology; Photoperiod; Schistosoma japonicum