Effects of a probiotic bacterial <Emphasis Type="Italic">Lactobacillus rhamnosus</Emphasis> dietary supplement on the crowding stress response of juvenile Nile tilapia <Emphasis Type="Italic">Oreochromis niloticus</Emphasis>     

Ana Teresa Gonçalves  Masashi Maita  Kunihiko Futami  Masato Endo  Takayuki Katagiri 《Fisheries Science》2011,77(4):633-642

To test the effects of probiotic bacteria against crowding stress, juvenile Nile tilapia Oreochromis niloticus were fed commercial feed supplemented with 1 × 10¹⁰ cfu/g pellets of Lactobacillus rhamnosus for 3 weeks. The fish were confined and subjected to crowding for 7 and 14 days after which their physiological condition was investigated. The administration of probiotic prophylaxis improved growth performance even in the stressed fish. After 7 days of stress exposure, fish receiving probiotic-supplemented feed showed proactive behavior and coping responses to the stressor, as evidenced by elevated plasma glucose levels and osmolality, stabilized plasma electrolytes, and a higher RNA:DNA ratio. Fish stressed for 7 days and fed normal commercial diet showed impairment of plasma electrolytes; after 14 days, the plasma osmolality, electrolytes, glucose, and RNA:DNA ratio decreased, indicating physiological maladaptation to the stressor. The growth rate was also found to be reduced, suggesting that energy demand exceeded the energy available from metabolism and dietary uptake. This latter effect was not observed in fish fed the probiotic-supplemented diet. The results suggest that probiotic bacteria prophylaxis may increase energy availability for metabolic support of the crowding stress response and improve the stress coping capacity of fish.  相似文献   

Embryonic development and morphology of eggs and newly hatched larvae of Pacific herring <Emphasis Type="Italic">Clupea pallasii</Emphasis>     

Tatsuya Kawakami  Hiroyuki Okouchi  Masato Aritaki  Jun Aoyama  Katsumi Tsukamoto 《Fisheries Science》2011,77(2):183-190

The embryonic development and morphology of eggs and newly hatched larvae of the Pacific herring Clupea pallasii were described using laboratory-reared specimens originating from the Miyako Bay stock. The eggs were almost spherical in shape, 1.33–1.46 mm (mean: 1.38 mm) in diameter, and had a thick adherent chorion. They had a segmented pale yellow yolk, no oil globule, and a relatively wide perivitelline space. A subgerminal cavity was observed during the gastrula period, whereas the blastocoel did not appear. Mass hatching occurred by 271 h 45 min after fertilization, and the newly hatched larvae were 7.1–7.7 mm (mean: 7.5 mm) in total length with 53–56 myomeres at 9.6°C. The embryonic development of Pacific herring was substantially similar to that of zebrafish Danio rerio, American shad Alosa sapidissima, as well as Atlantic herring Clupea harengus, and generally followed the basic developmental pattern of teleosts. However, Pacific herring larvae hatched at a more developed stage than some other clupeoids, such as Japanese sardine Sardinops melanostictus, and the progressed developmental stage at hatching could be interpreted as an advanced adaptation.  相似文献   

Determination of maturity in male hawksbill turtle <Emphasis Type="Italic">Eretmochelys imbricata</Emphasis> in captivity based on tail elongation and plasma testosterone level     

Masato Kobayashi  Tomohito Shimizu  Koichi Okuzawa  Kiyoshi Soyano  Kenzo Yoseda 《Fisheries Science》2010,76(5):777-784

To determine the sexual maturity of fourteen male wild-caught hawksbill turtles [straight carapace length (SCL) range 63–79 cm] held in captivity, we investigated their hormone levels in blood and morphological characteristics. Male turtles were divided into two groups: five individuals showing mating behavior (group A) and nine individuals not showing mating behavior (group B). Then, seasonal changes of plasma testosterone of both groups were studied. We also tried to determine male maturity based on tail elongation (TE) index, i.e., the ratio of tail length (TL) to SCL. Plasma testosterone level of group A gradually increased during premating and then sharply declined to low levels between mating and postmating seasons. In contrast, that of group B remained low during the experimental periods. The distinct seasonal changes of plasma testosterone levels of groups A and B correlated with their maturity. Furthermore, males were clearly divided into mature and immature based on TE values >0.35 and <0.33, respectively, corresponding to results based on plasma testosterone levels. Our results indicate that TE can be used more conveniently and accurately to determine maturity of male hawksbill turtles in captivity.  相似文献   

IgE reactivity to milk components in dogs with cutaneous adverse food reactions     

Hidekatsu SHIMAKURA  Tadahiro NASUKAWA  Jumpei UCHIYAMA  Ryosuke SUGIMOTO  Ichiro IMANISHI  Sumire OOTA  Keijiro MIZUKAMI  Masato FUJIMURA  Masahiro SAKAGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(10):1509

We investigated the IgE reactivity to crude and purified milk antigens in the sera of 112 dogs with cutaneous adverse food reactions (CAFRs). Of the 112 dogs, 33 (29%) had specific IgE for crude milk antigens. In the dogs with milk-specific IgE, IgE reactivity to casein, bovine serum albumin (BSA), α-lactalbumin, β-lactoglobulin, and bovine IgG were 81%, 85%, 39%, 27%, and 35%, respectively. Casein and BSA may be important allergens in dogs with CAFRs. Some canine vaccines contain casein hydrolysate as a stabilizer and the pooled serum with anti-casein IgE showed IgE reactivity to the vaccines containing it. Information about IgE reactivity to casein in dogs with CAFRs could be useful for predicting adverse reactions to the vaccines including casein hydrolysate.  相似文献   

α-Melanocyte-stimulating hormone directly increases the plasma calcitonin level and involves calcium metabolism in goldfish     

Ikari  Takahiro  Kobayashi  Yuki  Kitani  Yoichiro  Sekiguchi  Toshio  Endo  Masato  Kambegawa  Akira  Asahina  Kiyoshi  Hattori  Atsuhiko  Tabuchi  Yoshiaki  Amornsakun  Thumronk  Mizusawa  Kanta  Takahashi  Akiyoshi  Suzuki  Nobuo 《International Aquatic Research》2018,10(3):283-292

International Aquatic Research - The effects of α-melanocyte-stimulating hormone (α-MSH) on calcium metabolism were examined with goldfish. The scales on the left side of goldfish bodies...  相似文献   

High-yield SRI in West Java by decomposing straw in waterlogged paddy field     

Masato Oda  Kazunobu Toriyama  Shigeki Yokoyama 《Paddy and Water Environment》2018,16(4):887-891

System of Rice Intensification (SRI) often achieved higher yield than conventional practice. We identified the high-yielding farmers from the yield records of 1909 paddy fields belonging to an organic farmers’ association. Farmers whose yields were from 8.4 to 10.4 t ha^?1 were interviewed and their fields surveyed. Their yields had increased by an estimated average of 40% following the adoption of SRI practices. They applied 2–12 t ha^?1 of compost. Compared to the conventional practice, they shortened seedling age at transplanting from 27.4 to 17.6 days and reduced the number of seedlings per hill from 4–6 to 2–3, while hill spacing remained unchanged. Instead of intermittent irrigation which is recommended in standard SRI, they kept shallow flooding of 1–2 cm. Although they applied a lot of compost, no correlation was found between the amount of compost application and the yields. Instead, high-yielding farmers returned rice straw into waterlogged paddy after harvest, which presumably is an ideal condition for biological nitrogen fixation. This may occur around rice straw during decomposition under waterlogged condition and might supplement the negative nitrogen balance, thereby enabling the high yield as compared with conventional practices where the fresh rice straw is removed and/or burned.  相似文献   

Effect of hygrothermal treatment on wood properties: color changes and kinetic analysis using four softwood and seven hardwood species     

Miyuki U. Matsuo  Katsuya Mitsui  Isao Kobayashi  Mitsuhiro Kohara  Masato Yoshida  Hiroyuki Yamamoto 《Wood Science and Technology》2016,50(6):1145-1160

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Rhizoctonia blight of turnip green caused by Rhizoctonia solani AG-4 HG-III     

Hiroyuki Sekiguchi  Takeshi Toda  Erika Sato  Keisuke Tomioka  Hiroharu Murakami  Ryota Amemiya  Naoyuki Hirako  Masato Nakata  Mitsuro Hyakumachi  Seiya Tsushima 《Journal of General Plant Pathology》2015,81(6):454-456

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Nitrogen uptake by sago palm (Metroxylon sagu Rottb.) in the early growth stages     

Suzette B. LINA  Masanori OKAZAKI  Dorothea Sonoko KIMURA  Yoshiharu YANO  Koyo YONEBAYASHI  Masato IGURA  Marcelo A. QUEVEDO  Alan B. LORETO 《Soil Science and Plant Nutrition》2009,55(1):114-123

Previous trials have revealed variable responses of sago palm ( Metroxylon sagu Rottb.) to fertilizer application, particularly nitrogen (N). In the present study, we quantified the fertilizer use efficiency (FUE) of sago palm for the first time using ¹⁵N-labeled fertilizer in pot and field experiments. The pot experiment was conducted in Japan using a 2:1 mixture of sand to Philippine soil. The field experiment was conducted in Leyte in the Philippines. Both experiments consisted of three replicates in each of three treatments: control, ¹⁵N urea at 50 kg N ha⁻¹ and ¹⁵N urea at 100 kg N ha⁻¹. The N uptake of sago palm increased significantly, but inconsistently with increasing N application. The few instances of a significant increase in N uptake did not translate into significant improvements in growth parameters, except for the number of leaflets in the pot experiment. The FUE values for sago seedlings (< 6 months) in the pot experiment treated with 50 and 100 kg N ha⁻¹ were 10.5 and 13.2%, respectively, whereas for the 2-year-old sago palms in the field, the corresponding FUE values were 14.8 and 12.0%. The FUE values were similar at the two levels of N application in both experiments. Sago growth parameters appeared to be insensitive to N application, suggesting that the form of N and the timing of N fertilization are important factors for sago palms. Therefore, the use of N fertilizer in sago production can only be justified after determining and fully understanding the response of sago palm to N application.  相似文献   

RNA-silencing suppressors of geminiviruses   总被引：2，自引：0，他引：2  

Pradeep Sharma  Masato Ikegami 《Journal of General Plant Pathology》2008,74(3):189-202

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