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61.
Thanh Quang Dang‐Nguyen Hiep Thi Nguyen Tamas Somfai David Wells Nguyen Thi Men Nguyen Viet‐Linh Junko Noguchi Hiroyuki Kaneko Kazuhiro Kikuchi Takashi Nagai 《Animal Science Journal》2018,89(6):880-887
We investigated whether high‐quality in vitro matured (IVM) oocytes can be distinguished from poor ones based on the morphological changes after treatment with hyperosmotic medium containing 0.2 mol/L sucrose in pigs. We hypothesize that IVM oocytes maintaining round shape have higher quality than mis‐shapened oocytes following dehydration. Oocyte quality was verified by determining embryonic developmental competence using in vitro fertilization, nuclear transfer and parthenogenetic activation. In all cases, the round oocytes had greater (p < .05) developmental competence than that of mis‐shapened oocytes in terms of blastocyst rate and total cell number in blastocysts obtained after 6 days of in vitro culture. We also confirm that round aged oocytes are higher in quality than mis‐shapened aged oocytes. In an attempt to find out why high‐quality oocytes maintain a round shape whereas poorer oocytes become mis‐shapened following sucrose treatment, we examined the arrangement of actin microfilaments and microtubules. Abnormal organization of these cytoskeletal components was higher (p < .05) in mis‐shapened oocytes compared to round oocytes after 52 hr of IVM. In conclusion, sucrose treatment helps selection of high‐quality oocytes, including aged oocytes, in pigs. Abnormal cytoskeleton arrangements partly explain for low developmental competence of mis‐shapened oocytes. 相似文献
62.
Tserenpurev Bat‐Oyun Takehiko Y Ito Yadamjav Purevdorj Masato Shinoda Satomi Ishii Hoshino Buho Yuki Morinaga 《Animal Science Journal》2018,89(1):219-226
Airag, (Fermented horse milk) is a traditional milk product in Mongolia. Herders separate foals from their dams and tie them at a milking site during the daytime to produce airag. To evaluate the effects of horse management on the movement of dams, we tracked three dams in a herd in camp 1 during summer and camp 2 during autumn of 2013 and analyzed their movements during the milking (daytime) and non‐milking (nighttime) periods in an area famous for its high‐quality airag. Dams were gathered every 1.7 ± 0.0 h between 07.46 and 15.47 hours at the milking sites and milked 4.6 ± 0.2 times/day during the study period (86 days). Daily cumulative and maximum linear distances from the milking sites were longer (P < 0.01) during the non‐milking period than during the milking period. Daily home ranges were 91 and 26 times greater during the non‐milking period (P < 0.001) in camps 1 and 2, respectively. The greater range during the non‐milking period would reflect the spatial distributions of water, salt and forage. The dams initially used similar areas and gradually shifted their daily home ranges after several days. This shift suggests that the dams grazed farther afield as forage availability declined around the milking site. For better airag production and sustainable pasture use, our results provide insights useful for evaluating the effects of milking management on vegetation and soil in those pastures, for selecting the appropriate milking times and frequency, and for choosing the right timing to shift milking sites. 相似文献
63.
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
64.
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
65.
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
66.
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
67.
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
68.
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
69.
Pseurotins A1 (1) and A2 (2) were isolated from a culture broth of the fungal strain Aspergillus fumigatus WFZ-25 as stereoisomers of pseurotin A (3) in 2011. We also isolated 1 and 2 together with 3 from A. fumigatus OUPS-T106B-5 separated from the marine fish Mugil cephalus. In this study, we re-examined the stereochemistry of 1 and 2 using chemical transformation and the CD spectra, and found the relationship between the CD Cotton effect and the absolute configurations of 1 and 2, which led us to revise the stereostructure of pseurotin A2. 相似文献
70.