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Spatial distributions and foraging substrates of 11 surgeonfish species (family Acanthuridae) in an Okinawan coral reef
Full text linkSurgeonfishes (family Acanthuridae) are a main fish group in coral reefs. This study aimed to examine the species-specific and size-related spatial distribution, and foraging substrates of 11 surgeonfish species in relation to topographical features and substrate diversity. Six species (Ctenochaetus striatus, Acanthurus nigrofuscus, A. lineatus, A. japonicus, Naso lituratus, and Zebrasoma scopas) showed a greater density in the outer reefs with a higher coverage of rock. The former five species showed a significant positive utilization of rock as foraging substrate, whereas Z. scopas positively utilized dead corals and rock. For A. dussumieri and N. unicornis, greater densities of smaller-sized individuals were found in the inner reefs with higher coverage of coral rubble and sand, whereas larger-sized individuals were found in the outer reefs with a higher coverage of rock. Naso unicornis showed a significantly positive utilization of rock as foraging substrate. Ctenochaetus binotatus tended to show greater density in the outer reefs and a significant positive utilization of rock as a foraging substrate. Acanthurus nigricauda tended to show greater density in the inner reefs and a significant positive utilization of sand as foraging substrate. Zebrasoma velifer showed greater density of smaller-sized individuals in the inner reefs with higher coverage of live corals and dead corals, whereas larger-sized individuals tended to be greater in the outer reefs with a higher coverage of rock. Zebrasoma velifer showed a significant positive utilization of dead corals as foraging substrate. These results indicated that non-coralline substrates are the main indicator for maintaining surgeonfish species diversity.journal articl
Fixation and staining conditions of leukocytes observation in the koi carp swim bladder
Full text linkIdentification of leukocytes on tissue sections is important to elucidate the mechanism of swim bladder lesions. To determine the best fixative solution for a koi carp swim bladder, the swim bladders were fixed in 10% formalin, Bouin's, MFAA and Davidson's solution. The swim bladders fixed in MFAA or Davidson's solution were severely detached and twisted, whereas those fixed in 10% formalin and Bouin's solution kept their external shape. However, the majority of the 10% formalin-fixed specimens showed detachment of the tunica interna from the tunica externa under the light microscope. Therefore, Bouin’s solution was determined to be the most suitable fixing solution for the swim bladder. Imprints (head kidney-touched slides glass were fixed with Bouin's solution) and tissue sections of head kidney fixed in Bouin’s solution were stained with Mayer’s hematoxylin and eosin (HE) and May-Grünwald·Giemsa (MGG), and the best staining method for leukocytes identification was investigated. In the HE-stained specimens, identification of leukocytes by staining was difficult. On the other hand, MGG-stained specimens could be identified by staining. Fixation with Bouin's solution and MGG staining was determined to be the most suitable method for leukocytes identification in the swim bladder.編集：水産大学校departmental bulletin pape
Feasibility study of combined heat, power, and fuel supply system using bioethanol derived from marine debris for coastal fisheries facilities
Full text linkThe author has previously developed and published energy and resource flow models focusing on the post-collection process of marine debris. These models were designed to examine the technical and economic feasibility of establishing businesses with energy systems. One of the previous studies examined the economic feasibility of a microgrid system combining a styrene oil conversion device from drifted styrofoam and a cogeneration system (CGS). The current study focuses on the “biomass gasification furnace and methanol synthesis furnace” technology, which has a proven track record with woody biomass. If this methanol synthesis furnace could be applied to drifting marine debris, it would be an option for providing energy to coastal facilities. In this study, an energy flow model was developed that can easily calculate the energy flow of a methanol synthesis furnace, CGS, and fuel supply system using biomethanol obtained from coastal biomass such as marine debris. If only marine debris is taken into account, the amount of biomass will be insufficient. For this reason, discarded fish and food residues from fishing ports and fish processing plants were also evaluated. Furthermore, this biomethanol can be used together with waste cooking oil to synthesize biodiesel fuel (FAME), enabling various applications including marine fuel. Using this energy model, the potential for energy self-sufficiency for coastal fisheries facilities (fishing ports, fish processing plants, and fishing boats) was calculated. The calculation results show energy selfsufficiency as a function of changes in biomass volume. However, they also found it difficult to be self-sufficient in electricity, heat, and fuel at the same time. Additionally, an optimization model was developed to determine the optimal size of the CGS, demonstrating the potential to improve the energy self-sufficiency of coastal fishery facilities.編集：水産大学校departmental bulletin pape
Actual situation and factors behind the establishment of sixth sector industrialization fishing: A case study of a fisheries processing and selling company in N City of Yamaguchi Prefecture
Full text linkthe purpose of this study is to clarify how Company A of fisheries processing and sales Company A in N City, Yamaguchi Prefecture overcame the constraints and challenges of sixth industrialization, such as the existing industrial structure and the limitations of the capabilities of economic entities that many management entities face. In conclusion, with the cooperation of the fishery cooperative in Company A's efforts to become a sixth industrial, the fact that each employee was able to make use of their experience and know-how to overcome the constraints and issues. This is thought to have led to the establishment of the sixth industrialization.編集：水産大学校departmental bulletin pape