Effect of different algae used for enrichment of rotifers on growth, survival, and swim bladder inflation of larval amberjack Seriola dumerili     

Hiroyuki Matsunari  Hiroshi Hashimoto  Kentaro Oda  Yoshitsugu Masuda  Hitoshi Imaizumi  Kazuhisa Teruya  Hirofumi Furuita  Takeshi Yamamoto  Kazuhisa Hamada  Keiichi Mushiake 《Aquaculture International》2012,20(5):981-992

The effect of algae with different DHA contents used for the enrichment of rotifers on the growth performance, survival, and swim bladder inflation of larval amberjack Seriola dumerili was investigated. Rotifers were enriched with freshwater Chlorella vulgaris containing three levels of DHA (rotifer containing DHA 0.04, 0.60, 1.32?g DHA 100?g^?1 DM) and Nannochloropsis (0.04?g DHA 100?g^?1 DM; 2.54?g EPA 100?g^?1DM). The larvae were fed the enriched rotifers in triplicate from 3?days post-hatch for 7?days in static condition. The same algae used for rotifer enrichment were supplied to the larval tanks. Growth and survival rate of fish fed the rotifers enriched with Nannochloropsis were higher than those of fish fed the rotifers enriched with all three Chlorella treatments. Swim bladder inflation was lowest in fish fed the rotifers enriched with Nannochloropsis. The proportion of EPA was higher in fish fed the rotifers enriched with Nannochloropsis, while that of DHA increased proportionally with the DHA levels in the rotifers enriched with Chlorella. These results suggest that rotifers enriched with Nannochloropsis (EPA-rich rotifers) are effective to enhance growth and survival, but DHA instead of EPA is essential to improve the swim bladder inflation in amberjack larvae.  相似文献   

Relationship between prey utilization and growth variation in hatchery‐reared Pacific bluefin tuna,Thunnus orientalis (Temminck et Schlegel), larvae estimated using nitrogen stable isotope analysis     

Yosuke Tanaka  Hiroshi Minami  Yuka Ishihi  Kazunori Kumon  Kentaro Higuchi  Takeshi Eba  Akefumi Nishi  Hideki Nikaido  Satoshi Shiozawa 《Aquaculture Research》2014,45(3):537-545

In mass culture of Pacific bluefin tuna Thunnus orientalis, a marked growth variation is observed after they start feeding at 6–7 mm in body length (BL) on yolk‐sac larvae of other species, and the growth variation in tuna larvae is a factor leading to the prevalence of cannibalism. To examine the relationship between prey utilization and growth variation, nitrogen stable isotope ratios (δ¹⁵N) of individual larvae were analysed. A prey switch experiment was conducted under two different feeding regimes: a group fed rotifers (rotifer fed group), and a group fed yolk‐sac larvae of spangled emperor, Lethrinus nebulosus (fish fed group) from 15 days after hatching (6.87 mm BL). The fish fed group showed significantly higher growth than the rotifer fed group. Changes in the δ¹⁵N of the fish fed group were expressed as an exponential model and showed different patterns from those of the rotifer fed group. The δ¹⁵N of fast‐growing tuna larvae collected in an actual mass culture tank after the feeding of yolk‐sac larvae was significantly higher than those of the slow‐growing larvae, indicating that slow glowing larvae depended largely on rotifers rather than the yolk‐sac larvae.  相似文献   

Bacterial degradation of antibiotic residues in marine fish farm sediments of Uranouchi Bay and phylogenetic analysis of antibiotic-degrading bacteria using 16S rDNA sequences   总被引：3，自引：1，他引：3  

Teruya Maki  Hiroshi Hasegawa  Hiroyuki Kitami  Kyoko Fumoto  Yukihiro Munekage  Kazumasa Ueda 《Fisheries Science》2006,72(4):811-820

ABSTRACT:   Antibiotic residues in marine sediments of fish farms negatively influence microbial ecologic systems. The microbial degradation of antibiotic residues was experimentally examined in the marine sediments of Uranouchi Bay, to which one of five antibiotics was added. After incubation reducing physical factors, ampicillin, doxycycline, oxytetracycline, and thiamphenicol were significantly degraded, while josamycin maintained most of the initial amounts. The isolates resistant to ampicillin, josamycin, oxytetracycline, or thiamphenicol degraded each antibiotic in wide ranges of degrees, whereas the isolates degrading doxycycline were not obtained. Microbial degradation may contribute to the disappearance of ampicillin, doxycycline, oxytetracycline, and thiamphenicol in the fish farm. In contrast, the disappearance of josamycin would depend on physical factors, but the bacteria degrading josamycin at least exist in the marine sediments. Phylogenetic analysis using 16S rDNA sequences demonstrated that the antibiotic-resistant isolates formed several clusters in the Gram-positive bacterial group, the Flavobacterium–Cytophaga–Bacteroides group, and the proteobacteria subdivisions. The antibiotic-resistant bacterial population would be composed of various species including ubiquitous coastal bacterial groups. Several species of antibiotic resistant bacteria show antibiotic degradation activities, and appear to contribute to the disappearance of antibiotics in Uranouchi Bay.  相似文献   

Application of the colorimetric loop-mediated isothermal amplification (LAMP) technique for genotyping Cre-driver mice     

Masaki FUJIMOTO  Hiroshi KITAMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(4):507

The Cre-loxP system is widely used to investigate the cell-type specific roles of genes of interest. Cre-driver mice are required for cell-type specific knockout during the Cre-loxP reaction. To maintain Cre-driver mouse strains, Polymerase chain reaction (PCR)-oriented genotyping targeting the Cre gene cassette is usually conducted. In this study, we instead applied a colorimetric loop-mediated isothermal amplification (LAMP) method for Cre-genotyping. Among four sets of primers designed by the in silico program, one set effectively amplified the Cre cassette of three Cre-driver strains, but not of C57BL/6 mice. This LAMP-oriented method reduces assay time by less than half compared to the PCR-based method, and can be carried out using a conventional isothermal incubator. Applying this LAMP method may accelerate genotyping of Cre-driver mice.  相似文献   

Suppression of pseudorabies virus replication by a mutant form of immediate-early protein IE180 repressing the viral gene transcription   总被引：1，自引：0，他引：1  

Etsuro Ono  Satoshi Taharaguchi  Shinji Watanabe  Hideki Nikami  Yukio Shimizu  Hiroshi Kida 《Veterinary microbiology》1998,60(2-4):107-117

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Differences in rumen fermentation characteristics between low‐yield and high‐yield dairy cows in early lactation          下载免费PDF全文

Ahmad Sofyan  Makoto Mitsumori  Hideyuki Ohmori  Yutaka Uyeno  Toshiya Hasunuma  Kiyoshi Akiyama  Hiroshi Yamamoto  Hiroaki Yokokawa  Tsuneko Yamaguchi  Takumi Shinkai  Makoto Hirako  Shiro Kushibiki 《Animal Science Journal》2017,88(7):974-982

Relationship between rumen fermentation parameters, blood biochemical profiles and milk production traits in different yielding dairy cows during early lactation was investigated. Twelve dairy cows were divided into two groups based on their milk yield, that is low‐yield (LY) and high‐yield (HY) groups. Rumen fluid and blood were collected at 3 weeks prepartum and 4, 8 and 12 weeks postpartum. Results showed that proportions of acetate, propionate to total short chain fatty acids and acetate : propionate ratio were changed (P < 0.05) in both groups during the peripartum period, whereas butyrate and acetate : butyrate ratio were only altered in the HY group. Blood cholesterol, beta‐hydroxybutyric acid (BHBA) and glutamic oxaloacetic transaminase in the HY group were higher (P < 0.01) than those in the LY group. Principal component analysis revealed that milk yield and milk compositions were differently clustered between groups. These parameters showed similar direction with dry matter intake in the HY group and adverse direction in the LY group. Linear regression analysis indicated that butyrate was positively correlated with BHBA (P < 0.05) in the HY group. This study suggests that cows in the HY group seem to accommodate appropriately to negative energy balance in early lactation through rumen fermentation.  相似文献   

Correlation analysis of hypothalamic mRNA levels of appetite regulatory neuropeptides and several metabolic parameters in 28‐day‐old layer chickens          下载免费PDF全文

Kazuhisa Honda  Takaoki Saneyasu  Koji Aoki  Tomohiko Shimatani  Takuya Yamaguchi  Hiroshi Kamisoyama 《Animal Science Journal》2015,86(5):517-522

Various lines of evidence suggest that appetite‐related neuropeptides in the hypothalamus are regulated by adiposity signals such as leptin and insulin in mammals. In the present study, we examined age‐dependent changes in the weight of abdominal fat and hypothalamic mRNA levels of neuropeptide Y (NPY, an orexigenic neuropeptide) and proopiomelanocortin (POMC, a precursor of anorexigenic neuropeptides) in growing chickens at 7, 14, 21 and 28 days of age. Hypothalamic NPY mRNA levels were significantly (P < 0.05) decreased after 14 days of age, whereas hypothalamic POMC mRNA levels were significantly (P < 0.05) increased at 28 days of age. The percentage of abdominal fat was significantly increased after 14 days of age in chickens. We next examined the correlation of hypothalamic NPY and POMC mRNA levels and several parameters at 28 days of age. There were no significant correlations between hypothalamic mRNA levels of NPY or POMC and the percentage of abdominal fat. These findings suggest that the gene expressions of NPY and POMC do not depend on adiposity in chickens, at least in 28‐day‐old layer chickens.  相似文献   

Embryo and fetal position during pregnancy by ultrasonographic examinations in bottlenose dolphin (Tursiops truncatus)     

Fumio TERASAWA  Hiroshi AKIYAMA  Toru SAKURAGI  Shuto HANEDA  Chika SHIRAKATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1138

From 2012 to 2017, serial ultrasonographic evaluation of 5 healthy bottlenose dolphins, Tursiops truncatus, were performed over the course of 6 pregnancies in Enoshima Aquarium. A total of 98 ultrasonographic examinations were included in the study. In three out of six cases, two embryos were observed between umbilicus and genital slit, and side of umbilicus in the dam’s body. All embryos were located in right below the peritoneum and observed from 308 to 325 days pre-partum. These days were corresponding to from 58 to 61 days after copulation respectively. The diameter of the embryo sac was approximately 4 cm. In three cases, the fetal head was located in the dam’s left lateral between umbilicus and genital slit from approximately 90 days pre-partum to the parturition. A snout of fetus is at the top of the uterine horn, and the tail lies close to the cervix. All six calves were fluke-first births (breech presentation). It was conjectured that the contraction of the dam’s uterus during parturition forced the fetus to invert, and the fetal tail fluke was expelled from the dam’s body. In three cases, judging from orientation of fetal tail fluke faced towards left side of the dam, a fetal position might be RSL (Right Sacrum-Lateral) within the birth canal. In the other three cases, the left and right positions of the fetus and the dam’s body are reversed during pregnancy and parturition.  相似文献   

Flagellin glycosylation is ubiquitous in a broad range of phytopathogenic bacteria     

Yuki Ichinose  Fumiko Taguchi  Masanobu Yamamoto  Mayumi Ohnishi-Kameyama  Tatsuo Atsumi  Masako Iwaki  Hiromi Manabe  Mio Kumagai  Quan Thanh Nguyen  Chi Linh Nguyen  Yoshishige Inagaki  Hiroshi Ono  Kazuhiro Chiku  Tadashi Ishii  Mitsuru Yoshida 《Journal of General Plant Pathology》2013,79(5):359-365

Glycosylation of flagellin is known to be involved in filament stabilization, motility, and virulence in Pseudomonas syringae. Here we investigated flagellin glycosylation in other phytopathogenic bacteria. Analyses of deduced amino acid sequences, glycostaining, and molecular masses of purified flagellins revealed that flagellins from all phytopathogenic bacteria investigated were glycosylated. Furthermore, the flagellin in a glycosylation-defective mutant of Xanthomonas campestris pv. campestris (Xcc) had a reduced molecular mass, and motility and virulence of the mutant toward host leaves decreased. These results suggest that flagellin glycosylation is ubiquitous in most phytopathogenic bacteria and that flagellin glycosylation is required for virulence in Xcc.  相似文献   

Specific detection of potentially allergenic peach and apple in foods using polymerase chain reaction     

Watanabe S  Taguchi H  Temmei Y  Hirao T  Akiyama H  Sakai S  Adachi R  Urisu A  Teshima R 《Journal of agricultural and food chemistry》2012,60(9):2108-2115

Two PCR methods were developed for specific detection of the trnS-trnG intergenic spacer region of Prunus persica (peach) and the internal transcribed spacer region of Malus domestica (apple). The peach PCR amplified a target-size product from the DNA of 6 P. persica cultivars including 2 nectarine and 1 flat peach cultivar, but not from those of 36 nontarget species including 6 Prunus and 5 other Rosaceae species. The apple PCR amplified a target-size product from the DNA of 5 M. domestica cultivars, but not from those of 41 nontarget species including 7 Maloideae and 9 other Rosaceae species. Both methods detected the target DNA from strawberry jam and cookies spiked with peach and apple at a level equivalent to about 10 μg of total soluble proteins of peach or apple per gram of incurred food. The specificity and sensitivity were considered to be sufficient for the detection of trace amounts of peach or apple contamination in processed foods.  相似文献