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Due to rapid ocean warming at higher latitudes, northward habitat shifts of the dominant anadromous fish in the Northern Hemisphere, chum salmon (Oncorhynchus keta), have recently been reported. Physiological development is considered to be a trigger for habitat shifts during early life. However, the possibility of physiological adaptations to future ocean warming is not fully understood, because data on the physiological traits of juveniles, such as metabolic rate and swimming performance, are limited. Using swim tunnel respirometers, we identified the metabolic traits of different-sized chum salmon juveniles originating from the Sanriku coastal river, Japan, which is far from the northern feeding grounds. The weight gain of >2 g steeply increased the prolonged swimming performance, and the metabolic cost of swimming against the southward current in the Sanriku coast decreased with weight gain under the sea water temperature range of 8–12 °C. These findings indicate weight gain and inhabiting areas with temperatures < 13 °C might provide potential benefits for northward migration. These results will be valuable when assessing the increased costs associated with changing ocean conditions. [ABSTRACT FROM AUTHOR]

To understand the larval distribution, size variation, and stable isotope ratios of Japanese eel leptocephali in relation to the salinity front and their feeding ecology, larvae from 7 research cruises (2002–2013) in the North Equatorial Current (NEC) spawning area were examined. The smallest early‐stage larvae were distributed south of or near the salinity front, confirming that the salinity front is an important oceanic feature to understand spawning locations of the Japanese eel. Larger size larvae tended to distribute into higher latitudes. Transport to northern latitudes with their growth would facilitate transport into the Kuroshio region, but retention in the Subtropical Countercurrent (STCC) might be detrimental. Preleptocephalus isotope ratios reflected maternal ratios, but feeding‐stage leptocephali (8–56 mm) tended to have higher ∂15N values at lower latitudes typically in areas south of a salinity front. Feeding larvae quickly assimilate isotope ratios from the NEC after spawning and early growth. Large differences of ∂13C values of larvae between the NEC and STCC might vary with spatial baselines in the two currents. However, diel vertical migrations should be considered, because the isotope ratios in particulate organic matter distinctly depend on the depth. Comparisons among Japanese eel larvae and other taxa of leptocephali in the NEC illustrate the need for further studies on the trophic ecology of leptocephali. [ABSTRACT FROM AUTHOR]

Resource subsidies exert critical influences on recipient habitats with relatively higher perimeter-to-area ratios, such as headwaters in watersheds. However, little is known about how those subsidies contribute to the energy sources in recipient habitats where the perimeter-to-area ratio is low, such as large stream channels. Here, we show that the diet of small Japanese eels (Anguilla japonica) Les apports de ressources exercent des influences cles dans les habitats recepteurs caracterises par des rapports perimetre:superficie relativement importants, comme les cours superieurs de bassins versants. Les connaissances sur la contribution de ces apports aux sources d'energie dans les habitats recepteurs ou le rapport perimetrersuperficie est faible, comme les chenaux de grands cours d'eau, sont toutefois limitees. Nous demontrons que le regime alimentaire de petites anguilles du Japon (Anguilla japonica) de moins de 500 mm de longueur totale vivant le long de rives naturelles de chenaux de grands cours d'eau est majoritairement constitue de petits lombrics terrestres (Metaphire spp.). Des analyses d'isotopes stables montrent que les lombrics constituent les proies animales les plus importantes dans le regime alimentaire des anguilles (45 %-47 %) et representent la plus grande proportion de leur contenu stomacal (7 %-93 %). Les anguilles ingerent des lombrics dans les deux jours suivant une pluie au printemps, a l'ete et a l'automne, et la consommation de lombrics augmente parallelement aux precipitations. Ces constatations indiquent que les apports episodiques de lombrics modules par la pluie pourraient biaiser provisoirement le regime alimentaire des anguilles vers cette ressource allochtone, ce qui pourrait expliquer l'importante contribution de cet apport pour les consommateurs vivant dans les chenaux de grands cours d'eau. En outre, differentes especes de lombrics pourraient produire de multiples episodes d'apport au fil des saisons et fournir aux predateurs un apport soutenu, rehaussant la contribution a long terme de l'apport au regime alimentaire des predateurs. [Traduit par la Redaction], Introduction Local habitats are linked tightly by reciprocal energy subsidies from contiguous habitats, and across-habitat transfers of both materials and organisms frequently have key effects on local consumers and their [...]

To clarify the composition of food ingested by blue mussels (Mytilus edulis) in the Menai Strait, where the largest mussel bed in the United Kingdom lies, hydrodynamic observations with organic carbon and nitrogen biochemical analysis were conducted. This strait is characterized by a narrow channel and wide tidal flats with large tidal mixing that influences the distribution of particulate organic matter (POM), which is food for mussels. The maximum velocities of the tidal currents were estimated to be 0.5-1.0 m [s.sup.-1] during northeastward flow and 0.6-1.3 m [s.sup.-1] during southwestward flow. The residual current was southwestward and the water flux was estimated to be 510 [m.sup.3] [s.sup.-1], Field observations indicate that the inflow of pelagic phytoplankton into the strait mainly occurred in the northern region of the strait. Resuspcndcd benthic primary production, however, also causes higher chlorophyll-a concentration in the central region of the strait near the mussel bed and its contribution to mussel growth was estimated to be 22%-50%. The concentrations of chlorophyll-a and particulate organic carbon indicated that the POM in the strait mainly originated from detritus. Benthic microalgae is. however, an important factor to understand the total primary production in the strait. The consumption of the primary producers was estimated to be approximately 6.3 t C [day.sup.-1]. In the phytoplankton community, pelagic and thycopelagic (living in both pelagic and benthic environments) species comprised 59.3%-77.2% and 12.8%-40.7% of the cells, respectively. The primary production by resuspended benthic species in the Liverpool Bay region was considerably larger than that in the Menai Strait region. As a conclusion, the Menai Strait is an area with complex hydrodynamic conditions causing horizontal advection and resuspension of both pelagic and benthic phytoplankton, and this complex would cause the most suitable condition for mussel production. KEY WORDS: mussel, food supply, food consumption, particulate organic matter, phytoplankton, benthic microalgae, stable isotopes. Mytilus edulis, INTRODUCTION The blue mussel Mytilus edulis is one of the most important aquaculture species in the North Atlantic coastal regions. Approximately two-thirds of the total mussel production in the United [...]

A trochanteric fracture is one type of hip fracture. Management of postoperative pain after trochanteric fracture that is caused by decreased gliding between tissues in the lateral thigh is not established. The aim of this study was to examine the effect of compression of the thigh using an elastic bandage on trochanteric fracture after surgery. Multicenter randomized controlled trial was conducted in collaboration with the Comprehensive Rehabilitation Unit (sub-acute rehabilitation Unit) in two hospitals. Eligible volunteers (n = 34) with trochanteric fractures after surgery were randomly assigned to two groups. In the treatment group, participants practiced standing and walking under compression of the thigh with an elastic bandage. The control group was blinded to the intervention and practiced standing and walking under non-compression of the thigh with an elastic bandage. Both groups underwent a standard physical therapy program 2 times a day, daily. Two-way repeated measures of ANOVA showed significant main effect between the groups for gliding between tissue (p <.001), lateral femoral pain (p <.001), subcutaneous tissue thickness (p =.044). Compression of the thigh with an elastic bandage significantly improved subcutaneous tissue thickness, gliding between tissues, lateral thigh pain. Gait velocity improved with these functional improvements. [ABSTRACT FROM AUTHOR]

Rationale: Although the proportion of structural carbonates in vertebrate bones is low, the values of isotopes, namely stable oxygen (δ18O) and carbon (δ13C), in structural carbonates provide environmental and physiological information, which can be beneficial for estimating the palaeontological and ecological parameters of vertebrates. However, a few studies have analysed the isotopes of structural carbonates in modern teleost fishes, and a well‐developed protocol for sample preparation is lacking. Methods: We examined different pre‐treatment methods of preparing bone samples of three marine teleost fishes (Japanese flounder, Pacific bluefin tuna and yellowtail) and investigated the effects of the cleaning methods on the stable isotope values of structural carbonates among vertebrae in the same individual. Isotope values were analysed using isotope ratio mass spectrometry. Results: Physical cleaning was the most promising pre‐treatment method and resulted in δ18O values that were comparable to those of otoliths. Chemical treatments with NaOH and H2O2 changed the percentage of structural carbonates in the bone and affected δ18O and δ13C values. High‐temperature treatments, such as boiling and roasting, altered δ18O values due to the exchange of oxygen with environmental water or vapour. Conclusions: Our results suggest that chemical cleaning methods used to prepare bone phosphate or collagen samples for isotope analyses are not suitable for structural carbonates. Physical cleaning is the appropriate pre‐treatment method for analysing the isotopes of structural carbonates. Also, we emphasise that standardising the vertebral number is necessary to make δ13C values comparable between specimens in the same species. [ABSTRACT FROM AUTHOR]