Influence of offshore breakwaters on fish assemblage structure in the surf zone of a sandy beach in Tokyo Bay,central Japan     

Shota Mikami  Yukinori Nakane  Mitsuhiko Sano 《Fisheries Science》2012,78(1):113-121

To determine the effects of shore-parallel offshore breakwaters on the surf-zone fish assemblage structure of a sandy beach, three study sites (sheltered inshore of breakwater, between adjacent breakwaters, and exposed without breakwaters) were sampled at Ohnuki Beach in Tokyo Bay, central Japan, in September and December 2009 and March and June 2010. Although some physical variables (wave height, turbidity, and water depth) differed among the three sites, no differences were apparent among the sites in the numbers of fish species and individuals, or in the abundance of epibenthic invertebrates (a main fish prey). In addition, species and individual numbers of two dominant feeding groups (mysid and copepod feeders) showed no significant among-site differences. Cluster and ordination analyses confirmed the similarity in fish species composition among the three sites. Furthermore, the mean standard length of all fishes collected throughout the study period did not differ significantly among the sites, the overall results indicating that the presence of breakwaters had little effect on surf-zone fish assemblage structure in the study area, despite some breakwater-related differences in the abiotic environment.  相似文献   

Identification of vitamin B12 and pseudovitamin B12 from various edible shellfish using liquid chromatography–electrospray ionization/tandem mass spectrometry     

Yuri Tanioka  Shigeo Takenaka  Tadasu Furusho  Yukinori Yabuta  Yoshihisa Nakano  Fumio Watanabe 《Fisheries Science》2014,80(5):1065-1071

In this study, the vitamin B₁₂ contents were analyzed in the edible portions of various shellfish (bivalves and snails). High vitamin B₁₂ contents (30.5–53.3 μg/100 g wet weight) were detected in mussels, surf clams, bloody clams, and freshwater clams. However, scallops and abalone had extremely low vitamin B₁₂ contents (0.1–1.1 μg/100 g wet weight) which was attributed to only the muscle portions being edible. These results suggest that high levels of vitamin B₁₂ are accumulated in the viscera of shellfish. Vitamin B₁₂ levels were also significantly higher in bivalves than in snails. The corrinoid compounds purified from all bivalves were identified as “true” vitamin B₁₂ using liquid chromatography–electrospray ionization/tandem mass spectrometry. In edible snails, abalone, and pond snails, however, both vitamin B₁₂ and pseudovitamin B₁₂ (an inactive corrinoid) were observed to be the major and minor corrinoid compounds, respectively. Based on these results, we conclude that the whole bodies of these edible bivalves are excellent sources of vitamin B₁₂ for humans.  相似文献   

Visual thresholds for feeding and optimum light intensity for larval rearing of Asian seabass,Lates calcarifer (Bloch)     

Yukinori Mukai  Leong Seng Lim 《Aquaculture Research》2014,45(2):188-194

This study examined the retinomotor responses and prey ingestion rates of 10‐, 15‐, 20‐ and 30‐day‐old Asian seabass Lates calcarifer under different light intensities from 0 to 1000 lx to determine the visual thresholds. Subsequently, two age groups of seabass larvae were reared under light intensities of 10, 100 and 1000 lx to determine the optimum illumination in hatchery tanks. Retinomotor response was absent in 10‐day‐old larvae, but quite marked in 15‐ and 20‐day‐old seabass at 1 lx and higher. Ingestion of Artemia nauplii by 10‐day‐old larvae was almost zero at <1 lx, increased significantly at 1 lx, and was maximal at 10–100 lx. Artemia ingestion under dim light <1 lx improved with age, and older larvae took more prey in complete darkness due to the presence of rod cells (and also free neuromasts). Larvae from 13 to 26 days group had similar survival and growth at 10–1000 lx, however, from 5 to 10 days group showed similar survival rate with highest weight gain at 100 lx. Therefore, we recommend that hatchery rearing tanks be illuminated such that the larvae in the water are exposed to approximately100 lx.  相似文献   

Effects of Whole Grain Wheat Bread on Visceral Fat Obesity in Japanese Subjects: A Randomized Double-Blind Study     

Yosuke Kikuchi  Satomi Nozaki  Miki Makita  Shoji Yokozuka  Shin-ichi Fukudome  Takashi Yanagisawa  Seiichiro Aoe 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):161-165

Metabolic syndrome is a risk factor for cardiovascular diseases and has become increasingly common in Japan. Epidemiological studies show inverse associations between intake of whole wheat grains and metabolic syndrome, but few dietary intervention trials have investigated the effect of whole wheat grain consumption. It was investigated whether a diet in which refined wheat bread (RW diet) was substituted by whole grain wheat bread (WW diet) would reduce visceral fat obesity in Japanese subjects. A randomized double-blind placebo-controlled intervention study was conducted in 50 Japanese subjects with body mass index (BMI)?≥?23 kg/m². Subjects were randomly assigned WW (WW group) or RW diets (RW group) for 12 weeks. Blood samples and computed tomography scans were obtained every 6th week. The WW group showed decrease (?4 cm²) in visceral fat area (VFA) (p <?0.05), whereas the RW group showed no significant changes. These time-dependent changes were significantly different between the groups. WW diet led to significant and safe reductions in VFA in subjects with BMI?≥?23 kg/m². WW diet may contribute to preventing visceral fat obesity.  相似文献   

Histopathology of muscle in experimental acute swine erysipelas     

M Morita  C Nozaki  S Shibuya  M Okamoto 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1973,35(3):261-267

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Differences in Ibaraki virus RNA segment 3 sequences from three epidemics     

Uchinuno Y  Ito T  Goto Y  Miura Y  Ishibashi K  Itou T  Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(11):1257-1263

Phylogenetic tree and partial nucleotide sequence analysis of RNA segment 3 were conducted to compare the Ibaraki virus (IBAV) strains from three epidemics in Japan, and serotype 2 epizootic hemorrhagic disease virus strains isolated in Australia, Taiwan, and Canada. Each strain was classified relative to the Ibaraki disease (IBAD) epidemics, which occurred in 1959-1960, 1987, or 1997-1998. In particular, major variation of the gene was identified in the strains isolated after 1997 when a new type of IBAD with the abnormal birth was confirmed. Ibaraki viruses isolated in Japan were more closely related to Taiwanese and Australian strains based on genetics, while the Canadian strain was more distantly related.  相似文献   

Fecal progestagen and estrone during pregnancy in a giraffe: a case report     

Isobe N  Nakao T  Shimada M  Fukumoto Y  Watanabe H  Minami S  Noda A  Yoshimura Y 《The Journal of reproduction and development》2007,53(1):159-164

The present study was carried out to measure fecal progestagen and estrone concentrations during pregnancy in a giraffe and examine the possibility of utilizing this assay system for pregnancy diagnosis. Fecal samples were collected from a giraffe during her third and fourth parities and mixed with methanol to prepare a fecal solution. Diluted fecal solution was used for direct enzyme immunoassay for progestagen and estrone. The newborn calf from the third parity was viable, although that from the fourth parity died 5 days after calving. In the third parity, the giraffe's progestagen and estrone concentrations increased transiently from days 30 to 120 of pregnancy. Then, they decreased and remained low until day 330. This was followed by a drastic rise in both concentrations as parturition approached. Parturition caused a reduction in the progestagen and estrone concentrations of the feces. In the fourth parity, the progestagen concentration increased gradually after mating until day 320. This was followed by a reduction in the concentration until parturition. However, the estrone concentration fluctuated, and the duration and extent of the prepartum rise in concentration were shorter and lower than those of the third parity. The hormone dynamics of the third parity suggest the possibility of early pregnancy diagnosis by measuring progestagen or estrone between days 30 and 120 after mating.  相似文献   

Fatal winter dysentery with severe anemia in an adult cow     

Natsuaki S  Goto K  Nakamura K  Yamada M  Ueo H  Komori T  Shirakawa H  Uchinuno Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(9):957-960

An adult dairy cow fatally affected with winter dysentery was investigated pathologically and virologically. The cow had severe anemia and diarrhea with massive blood. Pathologically, the loss of surface epithelial cells and necrosis of crypt epithelial cells in the large intestine were observed. Bovine coronavirus (BCV) antigen was observed in necrotic crypt epithelial cells of the large intestine. Virus particles were found in the necrotic epithelial cells of the large intestine. Virologically, BCV was isolated from the feces of the dead cow. The dead cow had no serum antibody against BCV although the co-habitants did. These suggest that severe infection of BCV in the cow without the BCV antibody accompanied by severe hemorrhagic anemia resulted in the cow's death.  相似文献   

First capture of post-spawning female of the Japanese eel Anguilla japonica at the southern West Mariana Ridge     

Hiroaki Kurogi  Makoto Okazaki  Noritaka Mochioka  Tadao Jinbo  Hiroshi Hashimoto  Masanori Takahashi  Atsushi Tawa  Jun Aoyama  Akira Shinoda  Katsumi Tsukamoto  Hideki Tanaka  Koichiro Gen  Yukinori Kazeto  Seinen Chow 《Fisheries Science》2011,77(2):199-205

Two adult male freshwater eels, Anguilla japonica, were captured in June 2008 in the West Mariana Ridge (13°N, 142°E) in the North Pacific, but collections of females have yet to be reported. In September 2008, we successfully caught two adult female A. japonica, 55.5 and 66.2 cm in total length, in the adjacent but northern area (14°N, 143°E). Six newly hatched eel larvae (pre-leptocephali) were also collected by subsequent plankton sampling conducted near the female catch area. Female adults appeared to be in the post-spawning state, probably a considerable time after spawning, since a small number of remarkably regressed oocytes (50–250 μm in diameter) were observed in the ovaries. Capture of post-spawning female eels and newly hatched larvae near the Suruga Seamount (14°N) together with the previous collection of mature males in the southern area (13°N) corroborates that the area along the West Mariana Ridge is the spawning area of this species, but suggests that the eel spawning may occur over a wider area than previously expected.  相似文献   

Development of sensory organs and changes of behavior in larvae of the sutchi catfish, <Emphasis Type="Italic">Pangasianodon hypophthalmus</Emphasis>     

Yukinori Mukai  Audrey Daning Tuzan  Sitti Raehanah Muhamad Shaleh  Bernardette Mabel Manjaji-Matsumoto 《Fisheries Science》2010,76(6):921-930

Larvae of the sutchi catfish Pangasianodon hypophthalmus hatch with morphologically immature features, but sensory organs develop rapidly as the fish grow. By 1 day old, yolk-sac larvae showed notochord flexion, and by 2 days old larvae were observed to have consumed a large part of the yolk sac. At this stage, larvae had well-developed eyes, olfactory organs with ciliated receptor cells, inner ears with semicircular canals, and numerous taste buds, and they commenced ingestion of rotifers, Artemia nauplii, and artificial compound feed. Two-day-old larvae had many free neuromasts on the surface of the head and flanks and clearly showed rheotaxis. By 20 days old, free neuromasts in postflexion larvae had sunk under the skin. At this later stage, larvae swam against a water current and schooled along the side of the fish tank. Rapid development of sensory organs and notochord flexion would be an adaptation for survival in conditions of flowing water, as in the Mekong River. In this study, we show that development of the lateral line in the postflexion stage seems to be closely related to larval behavior, suggesting that these developments could be essential for sutchi catfish larvae survival.  相似文献