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81.
Katsuki Adachi Masaaki Omine Mitsuho Sugimoto Takanori Ishii Hiroshi Niimi Takayuki Suzuki 《Plant Production Science》2016,19(1):125-131
We developed transplantation cultivation method of case-held tuber seedlings (CTS), which was derived from direct planting method of seed tubers, and applied this method to the sweet potato cultivar Beniharuka. A plastic case made of polypropylene was designed for cultivation of CTS. Seed tubers of cultivar Beniharuka in the range of 30–80 g were cut in half. The half-cut tubers were placed inside the plastic cases, and the cases were filled with a commercial soil mix. The case-held tubers were incubated under natural sunlight in a glass house. After 3–4 wk, the CTS were transplanted into a field. Mother tuber (seed tuber) enlargement was suppressed by the plastic confinement of the cases, and daughter tubers were formed above the case as vine-root-originated tubers. In the field experiments in 2012 and 2013, daughter tuber yields were increased 19% and 21% by case-held tuber seedling transplanting (CTST) over conventional vine-planting (VP), the number of daughter tubers per plant in CTST were 36 and 68% higher than in VP, and the mother tuber yields were limited to 2.1 and 4.3% of the total fresh yield of mother and daughter tubers, respectively in 2012 and 2013. Application of CTST method to cultivar Beniharuka enhanced tuber yield, increased the number of daughter tubers per plant, downsized daughter tubers compared to VP, and mother tuber enlargement was suppressed by case-holding. The CTST method is expected to produce more and smaller good in shape tubers of cultivar Beniharuka compared to VP. 相似文献
82.
Keita Kodama Masaaki Oyama Jeong-Hoon Lee Yoshiaki Akaba Yoshihiro Tajima Takamichi Shimizu Hiroaki Shiraishi Toshihiro Horiguchi 《Fisheries Science》2009,75(4):875-886
To explore which lifestages affect the stock size of young-of-the-year mantis shrimp Oratosquilla oratoria in Tokyo Bay, Japan, we investigated interannual variations in the quantitative relationships among egg production, larval
density, and juvenile density. We collected adult females, larvae, and juveniles during monthly field surveys from 2004 to
2007. The interannual trend for the juvenile density index differed from those for egg production and larval density; although
indices of both egg production and larval density were high in 2004 and 2007, the juvenile density index was high only in
2007, suggesting high mortality during the pelagic larval stage or the early phase of the postsettlement juvenile stage in
2004. We found that larval settlement started at the end of August and peaked in October, although larvae from the early spawning
season (May–June) should have settled in August or earlier. Juveniles were found throughout the bay except in areas where
bottom hypoxia occurred, suggesting that hypoxia restricts the spatial distribution of juveniles. Our results suggest that
mortality during the early life history fluctuates among years, probably because of changes in environmental conditions in
the bay, resulting in interannual variation in the stock size of young-of-the-year juvenile O. oratoria. 相似文献
83.
Satoshi Watanabe Satoshi Katayama Masashi Kodama Naritoshi Cho Kaoru Nakata Masaaki Fukuda 《Fisheries Science》2009,75(4):937-945
The relative contribution of particulate organic matters (POMs) in water column and sediment as a food source for the Manila
clam, Ruditapes philippinarum, was studied using carbon and nitrogen stable isotopic method (δ13C and δ15N) in a tidal flat at Seaside Park, Yokohama, Japan. Comparisons of δ13C and δ15N among R. philippinarum and POMs in surface water, bottom water, and sediment surface indicated that R. philippinarum larger than 5 mm shell length (SL) mainly assimilated benthic POM, and individuals smaller than 5 mm SL assimilated benthic
and pelagic POM. Continuous measurements of chlorophyll concentrations in the bottom water revealed tide-driven resuspension
of the benthic phytopigments. R. philippinarum showed differences in δ13C and δ15N along an inshore–offshore transect, indicating small-scale spatial differences in POM provision in the tidal flat. These
findings suggest that POM in the bottom water, supposedly inhaled by R. philippinarum, is a mixture of a larger proportion of resuspended benthic POM and a smaller proportion of pelagic POM, and that the mixing
ratio of the POMs may be affected by the hydrodynamics of flooding water associated with tidal flat topography. 相似文献
84.
Jeong-Chae Park Masaaki Oyama Jeong-Hoon Lee Keita Kodama Yasuhiko Ohta Atsuko Yamaguchi Hiroaki Shiraishi Toshihiro Horiguchi 《Fisheries Science》2013,79(2):193-201
Reproductive traits are among the primary determinants of population dynamics, and their changes could affect stock size. We investigated differences in reproductive traits of the starspotted smooth-hound Mustelus manazo in Tokyo Bay between the 1990s (a low-stock period) and the 2000s (a high-stock period). Peak timings of mating (May–July), ovulation (May–June), and parturition (May–June) were similar between the two periods. However, the size at first maturity in the 2000s was smaller than that in the 1990s for both sexes. In addition, embryo-related parameters differed greatly between the two periods. Slopes of size–fecundity regression in the 2000s decreased to 43–73 % of the 1990–1996 values, suggesting a substantial decline in fecundity during the 2000s. Frequency distribution of the maximum ovum diameter during the ovulation season showed two distinct two modes in 1990s while it showed a substantial dispersion during the 2000s, implying that changes occurred in the developmental pattern of ova in the ovary. Undeveloped eggs were present in the uteri with low frequency from September to May during the 2000s, but they were totally absent from September through May in the 1990s. The increased number of remnant undeveloped eggs that did not become embryos may explain the fecundity decline during the 2000s. 相似文献
85.
Mikami O Nakajima H Kawashima K Yoshii M Nakajima Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):735-738
Reproductive failure associated with porcine circovirus type 2 (PCV2) was observed in a farm, and a weak-born 8-day-old piglet was examined pathologically. Focal to locally extensive lesions, including infiltration of macrophages and lymphocytes, fibrosis and degeneration of the myocardium were observed in the heart. PCV2 antigens and nucleic acids were detected in degenerated cardiomyocytes and macrophages infiltrating the heart by immunohistochemical staining and in situ hybridization. Depletion of lymphocytes with occasional infiltration of multinucleated giant cells was seen in the lymphoid organs and PCV2 antigens were demonstrated in histiocytic cells. Crystalline arrays of viral particles were observed in infiltrated macrophages in the heart and, rarely, in cardiomyocytes by electron microscopy. Although myocarditis is a common finding in aborted or stillborn piglets in reproductive failure due to PCV2, it was also observed in the 8-day-old piglet with PCV2 association. 相似文献
86.
C-reactive protein concentration in dogs with various diseases 总被引:1,自引:0,他引:1
Nakamura M Takahashi M Ohno K Koshino A Nakashima K Setoguchi A Fujino Y Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(2):127-131
To investigate the clinical utility of C-reactive protein (CRP) determination in dogs, its plasma concentration was measured by a laser nephelometric method in 928 dogs with various diseases, and was compared with other inflammatory parameters. CRP concentration was elevated in various inflammatory diseases, this was most frequently observed in cases with neoplastic and immune-mediated diseases. All cases of pyometra, panniculitis, acute pancreatitis, polyarthritis, and hemangiosarcoma showed significantly elevated CRP concentrations. On the other hand, the CRP concentration was elevated only in few cases of neurological diseases such as epilepsy, meningoencephalitis, and hydrocephalus and endocrine diseases such as hypothyroidism, hyperadrenocorticism, and diabetes mellitus. Only a weak correlation was observed between the CRP concentration and white blood cell (WBC) counts (r=0.44) but no correlation with band neutrophil counts. There was no correlation between the CRP and albumin concentrations, but a weak negative correlation (r=-0.40) when excluding chronic intestinal diseases and nephrotic syndrome, which can cause protein loss. Thus, CRP can be useful to detect inflammations that cannot be detected by WBC and, or band neutrophil counts, suggesting that the examination of CRP concentration is essential as routine diagnostic test. 相似文献
87.
88.
Mohammed ABDEL-HAKIEM Ayuko YAMASHITA Ayman ATIBA Yasuhiko OKAMURA Masaaki KATAYAMA Haroun YOUSSEF Hiroshi ISOMURA Yuji UZUKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):97-100
The pathogenesis of intervertebral disc (IVD) degeneration is not fully understood. The
biomolecular signaling pathways involved in the IVD degeneration require further
investigation. The aim of this study was to investigate the expression of NG2 proteoglycan
in the degenerated IVD. IVD samples were obtained from 16 Dachshunds that were confirmed
to have IVD herniation and subsequently underwent hemilaminectomy. The samples were
subjected to histological and immunohistochemical (IHC) examinations. IHC revealed
positive results for the expression of NG2 proteoglycan in all examined samples. The
results showed the expression of NG2 proteoglycan by the degenerated IVDs. 相似文献
89.
Akiko CHIBA Kaoru HATATE Rurika ONOMI Chiho KAWASHIMA Masaaki HANADA Tomoe MORIYAMA Akira GOTO Norio YAMAGISHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2020,82(11):1643
This study investigated consecutive fluctuations in serum activities of bone-specific alkaline phosphatase (ALP) isoenzyme 3 (ALP3) in 11 clinically healthy Holstein heifers during the first 18 months of life. ALP3 activities at the first sampling time point after weaning (3 months) were significantly lower than those at multiple time points during the pre-weaning period. Those activities increased from a minimum at 3 months to a peak at 6 months during the post-weaning period. In the anthropometric data, daily body weight and wither height gains appeared to be below the public data at 4 months and 4–5 months, respectively. The data suggested that serum ALP3 activity can be used to monitor skeletal growth of heifers at weaning. 相似文献
90.