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171.
Activities of enzymes related to glucose metabolism were measured in canine and feline liver. There were no significant differences in plasma glucose and immunoreactive insulin concentrations between dogs and cats. Glucokinase activities were absent in feline liver, however, activities of other glycolytic enzymes such as hexokinase, phosphofructokinase and pyruvate kinase, were significantly higher than those in canine livers. Activities of rate limiting enzymes of gluconeogenesis such as pyruvate carboxylase, fructose-1, 6-bisphosphatase and glucose-6-phosphatase in feline livers were significantly higher than those in canine livers. 相似文献
172.
Sakiko Orui Sakaguchi Shigeru Shimamura Yuichi Shimizu Gen Ogawa Yuichiro Yamada Keiko Shimizu Hiroaki Kasai Hiroshi Kitazato Yoshihiro Fujiwara Katsunori Fujikura Kiyotaka Takishita 《Fisheries Science》2017,83(1):47-56
To identify the stomach contents of marine organisms, morphological observations are commonly conducted. However, the results obtained by this traditional method are frequently biased, as it is difficult to detect partially digested, soft-bodied organisms. To resolve this, recent studies have used DNA-based (DNA barcoding) analyses to examine the diet breadth of marine organisms. Here, we compared the prey richness of juvenile fishes using morphological observations and DNA-based analyses, with a focus on juvenile chum salmon Oncorhynchus keta. A higher number of prey taxa were successfully identified using DNA-based analyses than morphological observations. However, we also noticed several shortcomings of the DNA-based analyses, as reported in other diet-analysis studies that used molecular techniques. For example, the degree of digestion among prey taxa might have resulted in differential sensitivity to DNA detection. Additionally, several prey taxa could not be precisely identified, as the sequence data for some of the targeted organismal groups are unavailable in public gene databases. Remarkably, it is also possible that DNA-based analyses detected secondary prey, and therefore, the richness of prey taxa was likely overestimated. Thus, dietary analyses of juvenile fishes need to be carefully conducted, considering the respective advantages and disadvantages of DNA-based and morphological techniques. 相似文献
173.
Hirofumi Furuita Tatsuya Unuma Kazuharu Nomura Hideki Tanaka Tsuyoshi Sugita & Takeshi Yamamoto 《Aquaculture Research》2009,40(11):1270-1278
This paper describes the relationship between the egg vitamin concentrations and the egg quality in the Japanese eel Anguilla japonica . No notable relation was found between any vitamin and the fertilization rate. Hatching and survival rates of larvae, however, significantly increased with an elevated level of egg vitamin C (VC). In contrast to VC, the relation between vitamins E (VE) and A (VA) concentrations and survival rate showed a clear peak, with a reduced survival rate at both higher and lower vitamin concentrations. The ratio of VE to lipid or highly unsaturated fatty acid (HUFA) in eggs positively correlated with hatching and survival rates of larvae. High-quality (HQ) eggs were determined as eggs that produced larvae having a survival rate higher than 80% at 8 days post hatch, and low-quality (LQ) eggs were determined as eggs that did not hatch. The level of VC of HQ was significantly higher than LQ. The results of this study suggest that HQ eggs, which produce larvae having a high survival rate, must have high levels of VC and VE/HUFA ratio and contain optimum levels of VA and VE in Japanese eel. 相似文献
174.
Fumiaki Takakuwa Keinosuke Suzuri Takao Horikawa Kunpei Nagahashi Shinichi Yamada Amal Biswas Hideki Tanaka 《Aquaculture Research》2020,51(3):1293-1302
Potato protein concentrate (PPC) is a promising candidate as a fish meal (FM) substitute because it has high protein and essential amino acid content. In the present study, we replaced FM in greater amberjack diets with PPC to investigate the effect on growth and feed utilization. Four isonitrogenous, isolipidic and isocaloric experimental diets were prepared by substituting 0, 20, 40 and 60% of FM protein with PPC (Control, P20, P40 and P60 respectively). The in vitro protein digestibility of protein in PPC was 88.8%, relative to 100% protein in the FM. The in vitro protein digestibility of protein in the experimental diets also decreased with increasing PPC and was lowest at 84.2% in P60. After the 7‐week feeding trial, final body weight, weight gain and thermal growth coefficient tended to decrease with increasing PPC and were significantly lower in P60 than in the control (p < .05). Further, fish fed with diets P40 and P60 showed significantly lower feed conversion and protein efficiency ratios than the control group (p < .05). In conclusion, the results suggest that PPC can replace up to 20% of FM in the diet of greater amberjack without compromising the growth performance or feed efficiency. 相似文献
175.
Hidekatsu Yamazaki Wataru Aoyama Eiji Masunaga Mamoru Tanaka 《Aquaculture Research》2019,50(4):1107-1116
A field campaign was conducted around salmon cages, using a combination of a towed ADCP and a free‐fall multi‐parameter profiler, in order to investigate flow structures and the possible distribution of effluent materials. Two transect observations showed that hydrographic conditions changed dramatically within 5 days, from highly stratified open water conditions to weak stratification. Three‐dimensional observation revealed that flow was blocked behind the cages and that the blockage was reduced as the distance from the cages increased. The flow speed was positively correlated with the intensity of the backscattering signal. The R2 value was high immediately behind the cages and decreased with distance from the cages. The flow time series behind the cages exhibited a k–2 power law spectrum that was consistent with a typical internal wave spectrum. This suggests that eddies shed from the cages were highly influenced by stratification. We estimated the rate of kinetic energy dissipation, , from YODA Profiler data based on the Thorpe scale approach. We also estimated the eddy diffusivity coefficient, . Both and followed a lognormal probability density function. The mean was consistent with a one‐dimensional diffusion model assessed from the R2 values of flow speed and backscatter intensity. 相似文献
176.
177.
Nor Zulkiply Amalina Zulperi Dzarifah Mohammad Noor Azmai Amal Mohd Termizi Yusof Mohd Zamri‐Saad Nurhidayu Al‐saari Mami Tanaka Sayaka Mino Tomoo Sawabe Md Yasin Ina‐Salwany 《Aquaculture Research》2019,50(11):3202-3210
Vibrio infections are common among marine fish and lead to serious problems in the aquaculture sector. This study reports a recent occurrence of Vibrio species (spp.) isolated from cultured groupers in Peninsular Malaysia using the gyrB and pyrH genes. A total of 147 Vibrio strains were successfully isolated from 77 (64%) groupers using culture method and subjected to gyrB and pyrH sequencing for species identification and confirmation. Results showed that 89% of Vibrio strains were identified and clustered to six groups of Vibrio spp., while 11% were not clustered to any Vibrio spp. using the gyrB sequences. Meanwhile, by analysis of the pyrH sequences all the 147 Vibrio strains (100%) were successfully identified and clustered into 11 groups of Vibrio spp., including the gyrB non‐identified strains. The pyrH gene provides a better resolution for identification of Vibrio spp. compared with the gyrB gene. Thus, the pyrH gene was more suitable for a rapid determination of Vibrio spp. distribution in Peninsular Malaysia. Using the pyrH gene, our study found higher prevalence of Vibrio vulnificus (33%), V. alginolyticus (24%) and V. parahaemolyticus (22%), followed by V. rotiferianus (5%), V. harveyi (3%), V. tubiashii (2%), V. campbellii (2%), V. ponticus (1%), V. diabolicus (1%), V. owensii (1%) and others Vibrio sp. (7%). Thus, the results of this study revealed that the occurrence of pathogenic vibrios among grouper fish is still high in Malaysian aquaculture. In addition, the pyrH gene was proved as a suitable marker for rapid identification of Vibrio species compared with the gyrB gene. 相似文献
178.
Eiji Tanaka 《Fisheries Science》2009,75(3):629-639
Biological and life-cycle information is essential to any fisheries management program. We have investigated temporal changes
in growth parameters in the von Bertalanffy growth curve for green turtles, Chelonia mydas, in waters around the Ogasawara Islands. The variance model of individual variability of growth used in our study was one
derived from the stochastic differential equation with the white noise of constant intensity. Maximum likelihood estimates
of the parameters were made using the data of 102 recovery records of tagging experiments from 1974 to 1995. The estimations
were carried out for each of two models of linear and sudden changes in the parameters, and the best model was selected using
Akaike's information criterion. The selected model was that all of the parameters excepting asymptotic straight carapace length
were linear functions of year and that the asymptotic length was constant over the years. The estimated values of the growth
coefficient in 1974 and 1995 were 0.0317 and 0.192 per year, respectively, and the estimated value of the asymptotic straight
carapace length was 97.2 cm. Implications of the results and future issues to be resolved in near future are discussed. 相似文献
179.
Yoshio Kurahashi Shinji Sakawa Haruhiko Sakuma Keiko Tanaka Gerd Haenssler Isamu Yamaguchi 《Pest management science》1999,55(1):31-37
Carpropamid (WIN™, KTU 3616) provides good control of leaf and panicle blast by ‘one-shot’ nursery-box treatment. It inhibits melanin biosynthesis in appressorial cells of Pyricularia oryzae, making them hyaline. Penetration by infection hyphae from the hyaline appressoria into rice epidermal cells is substantially hindered. In addition, the spread of rice blast spores from primary lesions to the other parts of the plant leading to secondary infection is largely prevented when the plants are treated with carpropamid by spray or water surface application. Secondary infection was simulated in a glass chamber fitted with an ultrasonic humidifier. On treated plants, many blast spores formed in the lesions, but the number of air spora that were dispersed from the lesions decreased significantly. A similar suppression of the spore liberation was observed in vitro when lesions on rice leaf segments, or discs from Pyricularia cultures on oatmeal agar were treated with the chemical. Spores from treated lesions or from the cultures on oatmeal agar amended with the chemical germinated normally and produced well-melanized appressoria on cellophane membranes. In addition, the spores proved to be fully pathogenic towards rice seedlings, producing normal disease symptoms. These results strongly suggest that carpropamid reduces the secondary infection of rice by Pyricularia by specifically hindering spore liberation. © 1999 Society of Chemical Industry 相似文献
180.
Katsuyuki Hayakawa Keiko Tanaka Toshiki Nakamura Shigeru Endo Tsuguhiro Hoshino 《Cereal Chemistry》1997,74(5):576-580
The viscoelastic properties and molecular structure of the starch isolated from waxy (amylose-free) hexaploid wheat (WHW) (Triticum aestivum L.) were examined. WHW starch generally had lower gelatinization onset temperature, peak viscosity, and setback than the starch isolated from normal hexaploid wheat (NHW). Differential scanning calorimetry (DSC) showed that WHW starch had higher transition temperatures (To, Tp, and Tc) and enthalpy (ΔH) than NHW starch. However, when compared on the basis of amylopectin (AP) content, ΔH of WHW starch was almost statistically identical to that of its parental varieties. Typical A-type X-ray diffraction patterns were observed for the starches of WHW and its parental varieties. Somewhat higher crystallinity was indicated for WHW starch. WHW starch was also characterized by having greater retrogradation resistance. The high-performance size-exclusion chromatography (HPSEC) of amylopectin showed that each amylopectin yielded two fractions after debranching. Although WHW amylopectin had somewhat long B chains, little difference was observed in the ratio of Fr.III/ Fr.II between WHW and its parental varieties. 相似文献