Naupliar copepod concentrations in the spawning grounds of Japanese sardine, Sardinops melanostictus, along the Kuroshio Current     

YOSHIRO WATANABE  HIROMU ZENITANI  RYO KIMURA  CHIKAKO SATO  YUTAKA OKUMURA  HIROYA SUGISAKI  & YOSHIOKI OOZEKI 《Fisheries Oceanography》1998,7(2):101-109

Naupliar copepods were distributed at similar concentrations over the waters inshore and offshore of the Kuroshio Current off central Japan in early spring 1993 and 1994, overlapping with the distribution of early feeding larvae of Sardinops melanostictus . Although N, P, Si and chlorophyll a concentrations were higher in the waters inshore of the Kuroshio axis than in the offshore waters, the mean concentrations of nauplii were not statistically different between the two waters. Food availability for larval S. melanostictus did not seem to be different between the two waters in terms of the mean food concentrations. Using the critical food concentration (>9 nauplii L^–1) for 25% survival during 3 days after first feeding derived from a rearing experiment, percentages in number of stations or water samples with nauplii concentrations >9 nauplii L^–1 were higher in the inshore waters than in the offshore waters in both years examined. Considering that fish larvae may depend on small-scale patchiness of food for their survival, the inshore waters seemed to be more favourable for first-feeding larvae than the offshore waters.  相似文献   

Evidence of a local spawning site of marine eels along northeastern Japan, based on the distribution of small leptocephali   总被引：3，自引：0，他引：3  

YOBUO KIMURA  MICHAEL J. MILLER  GEN MINAGAWA  SHUN WATANABE  AKIRA SHINODA  JUN AOYAMA  TADASHI INAGAKI  KATSUMI TSUKAMOTO 《Fisheries Oceanography》2006,15(2):183-190

Evidence of recent spawning by several species of marine eels of the families Congridae, Ophichthidae, and Nettastomatidae was found over the continental shelf along the coast of northeastern Japan in October 2003. Sixty‐three leptocephali of at least three taxa that ranged from 3.8 to 12.3 mm total length were collected in a relatively small area, just to the south of Cape Shioya, primarily over the 100‐and 200‐m‐depth contours. The leptocephali of Gnathophis nystromi nystromi were the most abundant, followed by those of G. nystromi ginanago. This spawning area is located in an area that appeared to include water originating from the Tsugaru Warm Current and is further south than the typical latitude of the cold water of the Oyashio First Intrusion. These findings suggest that some species of marine eels may not migrate past the slope to spawn, and that the oceanographic features of the region may provide favorable conditions for the growth and retention of leptocephali in the area to the south of Cape Shioya.  相似文献   

Prolactin gene expression in mouse pancreatic islets   总被引：1，自引：0，他引：1  

Toshio HARIGAYA  Michiko KOMORI  Harumi WATANABE  Satoshi WATANABE  Takuji MATSUI 《Animal Science Journal》2002,73(1):29-34

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Age-related changes in leukocytes and T cell subsets in peripheral blood of Japanese Black cattle     

Sachi TANAKA  Kohtaro MIYAZAWA  Atsuko KUWANO  Kouichi WATANABE  Shyuichi OHWADA  Hisashi ASO  Shigeru NISHIDA  Takahiro YAMAGUCHI 《Animal Science Journal》2008,79(3):368-374

It is well known that the immune system changes with age during development and maturation in Holstein cattle. But age-related changes in leukocytes and T cell subsets in peripheral blood of Japanese Black cattle still remain unclear. The aim of the present study was to investigate comparative changes of leukocytes (granulocytes, monocytes, B cells and T cells) and T cell subsets (CD4⁺, CD8⁺, γδ, CD8⁺γδ and WC1⁺γδ T cells) in Japanese Black cattle aged 0.5, 1, 2, 6, 18 and 36–41 (adult) months on flow cytometry using specific monoclonal antibodies for the cell surface markers. T cell proportion was approximately 40% in 2-month-old cattle and decreased to 20.6% in adults. In contrast, B cell proportion significantly increased from 7.4% to 28.2% with age. In T cell subsets the percentage of CD4⁺ T cells significantly increased from 40.5% to 60%, but that of WC1⁺γδ T cell subset significantly decreased with age. The percentages of CD8⁺ and CD8⁺γδ T cells did not change. The present study details the proportional changes in leukocyte and T cell subsets with age in the peripheral blood of Japanese Black cattle and these findings are similar to those described for Holstein cattle.  相似文献   

Ultrastructural Study on Colocalization of Glucagon-Like Peptide (GLP)-1 with GLP-2 in Chicken Intestinal L-Cells     

Kei NISHIMURA  Kohzy HIRAMATSU  Mohammad M. MONIR  Chihiro TAKEMOTO  Takafumi WATANABE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2013,75(10):1335-1339

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Cystic Rete Testis with Testicular Dysplasia in a Rabbit     

James K. CHAMBERS  Kazuyuki UCHIDA  Yousuke MURATA  Ken-ichi WATANABE  Kenichiro ISE  Yasutsugu MIWA  Hiroyuki NAKAYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(5):751-755

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Microbial biomass and nitrogen transformations in surface soils strongly acidified by volcanic hydrogen sulfide deposition in Osorezan, Japan     

Mirai WATANABE  Shigeki YAMAMURA  Takejiro TAKAMATSU  Masami K. KOSHIKAWA  Seiji HAYASHI  Tomoyoshi MURATA  Shoko S. SAITO  Kazuyuki INUBUSHI  Kazunori SAKAMOTO 《Soil Science and Plant Nutrition》2010,56(1):123-132

Volcanic acidification has created unique ecosystems that have had to adapt to the acidic environments in volcanic regions. To characterize the primary microbial properties of strongly acidified soils in such environments, we investigated microbial biomass, nitrogen transformations and other relevant chemical properties in the surface soils of solfatara and forests from Osorezan, a typical volcanic region in Japan, and compared the results to common Japanese forest soils. Soil microbial biomass C (MBC) and N (MBN) were determined using the chloroform fumigation–extraction method. Potential net N mineralization and net nitrification were measured in aerobic laboratory incubations. Long-term acidification in the Osorezan soils by volcanic hydrogen sulfide deposition caused low soil pH (3.0–3.8), base cation deficiency and increased concentrations of toxic ions such as Al³⁺. The proportions of MBC to total carbon (MBC/TC ratio) and MBN to total nitrogen (MBN/TN ratio) were lower than those in common Japanese forest soils. The extreme acidic conditions may have inhibited microbial survival in the Osorezan acid soils. Net N mineralization occurred at rates comparable to those in common Cryptomeria japonica forest soils, probably because of the presence of acid-tolerant soil microorganisms. Net nitrification was completely inhibited and autotrophic ammonia oxidizers were not detected by the MPN method. The inhibition of nitrification prevents nitrogen leaching from the soils, thus maintaining a nitrogen cycle in the volcanic acid region in which     (and NH₃) is recycled among microorganisms and plants.  相似文献   

Death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer and their progeny: a result of nationwide survey in Japan     

Shinya WATANABE  Takashi NAGAI 《Animal Science Journal》2009,80(3):233-238

To obtain the data concerning death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer (SCNT) and their progeny produced by Japanese institutions, a nationwide survey was carried out in July-August, 2006. As a result, lifetime data concerning 482 SCNT cattle (97.5% of cattle produced in the country at that time) and 202 progeny of SCNT cattle were accumulated and the death loss of these cattle was analyzed. Although 1/3 of delivered SCNT calves died during the perinatal period due to stillbirth and neonatal death, incidence of death loss due to diseases in SCNT cattle surviving more than 200 days after birth seems to be the same as these in conventionally bred cattle. In contrast, progeny of SCNT cattle showed the same level in death loss as observed in conventionally bred cattle throughout their lifetime. These results suggest that robust health would be expected in SCNT cattle surviving to adulthood and their progeny.  相似文献   

Recombinant expression and characterization of three group IB phospholipase A₂ isoforms in the red sea bream Chrysophrys major     

Yukichi  FUJIKAWA  Mariko  SHIMOKAWA  Shoko  WATANABE  Akiko  TAKEHARA  Satoshi  UCHIYAMA  Seiichi  HAYASHI  Muneharu  ESAKA  Hiroshi  MIYAMOTO  Mitsumasa  MANKURA  Noriaki  IIJIMA 《Fisheries Science》2003,69(6):1263-1270

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Circulating activin A during equine gestation and immunolocalization of its receptors system in utero-placental tissues and fetal gonads     

Pramod DHAKAL  Nobuo TSUNODA  Yasuo NAMBO  Hiroyuki TANIYAMA  Kentaro NAGAOKA  Gen WATANABE  Kazuyoshi TAYA 《Journal of Equine Science》2021,32(2):39

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