Antarctic krill Euphausia superba plays a key role in the Antarctic food web.The trophic linkage between krill and other macro-organisms has been studied in the past decades,but the variability of parasites in krill i...Antarctic krill Euphausia superba plays a key role in the Antarctic food web.The trophic linkage between krill and other macro-organisms has been studied in the past decades,but the variability of parasites in krill is less studied and remains poorly understood.Therefore,it is important to understand the factors that influence abundance and infection of parasites in krill.Moreover,the relationship between the infection intensity of parasite and krill diet needs to be clarified,which is helpful for understanding the role of parasite in the food web.We investigated the abundance of the highly prevalent gregarine parasites in the digestive tract of krill and the factors influencing the gregarine infection to krill in the East Antarctic.The infection rate of Cephaloidophora pacifica Avdeev,1985 to krill(n=50 individuals)was 94%.The results of generalized linear model show the infection intensity of C.pacifica to the host was related significantly to the station,krill size,and maturity stage,but not the food species and abundance in the stomach of krill.Abundance of C.pacifica in krill differed among stations,and the lowest abundance occurred in the station nearest to the coast.Gregarines abundance varied among sexual maturity stages of krill and increased with krill size.展开更多
基金Supported by the‘Inter-governmental Science and Technology Innovation(STI)Cooperation Special Program’of the National Key Research and Development Program(No.2023 YFE 0104500 to GPZ)。
文摘Antarctic krill Euphausia superba plays a key role in the Antarctic food web.The trophic linkage between krill and other macro-organisms has been studied in the past decades,but the variability of parasites in krill is less studied and remains poorly understood.Therefore,it is important to understand the factors that influence abundance and infection of parasites in krill.Moreover,the relationship between the infection intensity of parasite and krill diet needs to be clarified,which is helpful for understanding the role of parasite in the food web.We investigated the abundance of the highly prevalent gregarine parasites in the digestive tract of krill and the factors influencing the gregarine infection to krill in the East Antarctic.The infection rate of Cephaloidophora pacifica Avdeev,1985 to krill(n=50 individuals)was 94%.The results of generalized linear model show the infection intensity of C.pacifica to the host was related significantly to the station,krill size,and maturity stage,but not the food species and abundance in the stomach of krill.Abundance of C.pacifica in krill differed among stations,and the lowest abundance occurred in the station nearest to the coast.Gregarines abundance varied among sexual maturity stages of krill and increased with krill size.