The rapa whelk Rapana venosa transforms from a phytophagous larva to a camivorous juvenile after settlement and metamorphosis.The high mortality rate and low metamorphosis rate(<1%)of larvae are among the key facto...The rapa whelk Rapana venosa transforms from a phytophagous larva to a camivorous juvenile after settlement and metamorphosis.The high mortality rate and low metamorphosis rate(<1%)of larvae are among the key factors limiting the recovery of the resources ofR.venosa.We studied these two processes and showed that the larva has the ability to settle and metamorphose in the middle and late 4 spiral whorl period,and the use of substrates(scallop shells with oysters)can significantly improve the settlement and metamorphosis rate of larvae.The presence of darkness,juvenile bivalve shellfish,and oyster polysaccharide could effectively increase the rates of larval settlement and metamorphosis.Our findings broaden the understanding of settlement and metamorphosis in gastropods and can be used to improve population control,resource recovery and commercial breeding strategies for R.venosa.展开更多
The identifying of the preferred breeding sites of sand fly immature forms is quite important to the understanding of the vector’s biology and the development of more effective control strategies for leishmaniasis. I...The identifying of the preferred breeding sites of sand fly immature forms is quite important to the understanding of the vector’s biology and the development of more effective control strategies for leishmaniasis. In the present study, it was analyzed experimentally;the potential of dog feces of serving as breeding substrate to Lutzomyia longipalpis. Two situations were tested: 1) the life cycle of the insects from larvae to adults, 2) the whole cycle from adults to adults. Our results demonstrated for the first time that: 1) L. longipalpis can be easily bred in dog feces, suggesting that it could represent a potential raising substrate to immature forms for this species;2) L. longipalpis larvae are able to make galleries on a substrate, literally burying themselves in this to function also as a shelter;3) from the previous information that dogs infected with Ancylostoma caninum can present dodecanoic acid in their feces, we suggested that this substrate may be particularly more attractive to L. longipalpis females seen that this molecule is the same component of their oviposition pheromone, which is produced by the accessory glands and secreted onto the eggs;4) after the copulation the males may landing on the substrate and continued beating the wings intermittently until the death in a similar behavior also noticed in other situations associated to kairomones response or pheromone production. Therefore, we suggested that it is very likely that dog excrements could serve as an important breeding substrate for L. longipalpis in endemic areas of visceral leishmaniasis in the New World.展开更多
基金Supported by the National Natural Science Foundation of China(No.31572636)the Natural Science Foundation of Shandong Province(No.ZR2019BD003)+4 种基金the China Postdoctoral Science Foundation(No.2019M652498)the Earmarked Fund for Modern Agro-industry Technology Research System(No.CARS-49)the Special Funds for Talent Project of Taishan Industry Leaderthe ‘Double Hundred’ Blue Industry Leader Team of Yantaithe Creative Team Project of the Laboratory for Marine Ecology and Environmental Science,Qingdao National Laboratory for Marine Science and Technology(No.LMEES-CTSP-2018-1)
文摘The rapa whelk Rapana venosa transforms from a phytophagous larva to a camivorous juvenile after settlement and metamorphosis.The high mortality rate and low metamorphosis rate(<1%)of larvae are among the key factors limiting the recovery of the resources ofR.venosa.We studied these two processes and showed that the larva has the ability to settle and metamorphose in the middle and late 4 spiral whorl period,and the use of substrates(scallop shells with oysters)can significantly improve the settlement and metamorphosis rate of larvae.The presence of darkness,juvenile bivalve shellfish,and oyster polysaccharide could effectively increase the rates of larval settlement and metamorphosis.Our findings broaden the understanding of settlement and metamorphosis in gastropods and can be used to improve population control,resource recovery and commercial breeding strategies for R.venosa.
文摘The identifying of the preferred breeding sites of sand fly immature forms is quite important to the understanding of the vector’s biology and the development of more effective control strategies for leishmaniasis. In the present study, it was analyzed experimentally;the potential of dog feces of serving as breeding substrate to Lutzomyia longipalpis. Two situations were tested: 1) the life cycle of the insects from larvae to adults, 2) the whole cycle from adults to adults. Our results demonstrated for the first time that: 1) L. longipalpis can be easily bred in dog feces, suggesting that it could represent a potential raising substrate to immature forms for this species;2) L. longipalpis larvae are able to make galleries on a substrate, literally burying themselves in this to function also as a shelter;3) from the previous information that dogs infected with Ancylostoma caninum can present dodecanoic acid in their feces, we suggested that this substrate may be particularly more attractive to L. longipalpis females seen that this molecule is the same component of their oviposition pheromone, which is produced by the accessory glands and secreted onto the eggs;4) after the copulation the males may landing on the substrate and continued beating the wings intermittently until the death in a similar behavior also noticed in other situations associated to kairomones response or pheromone production. Therefore, we suggested that it is very likely that dog excrements could serve as an important breeding substrate for L. longipalpis in endemic areas of visceral leishmaniasis in the New World.
