Watanabe K.,Hokkaido National Fisheries Research Institute |
Sasaki K.,Tohoku National Fisheries Research Institute |
Saito T.,Hokkaido National Fisheries Research Institute |
Ogawa G.,Iwate Fisheries Technology Center
Fisheries Science | Year: 2015
The Great East Japan Earthquake may have resulted in increased mortality of artificially propagated chum salmon fry (2010 year class) from Iwate Prefecture (CSI), both in the hatchery and after release. Individuals from the 2010 year class will return in 2014–2015. To evaluate the potential for future issues associated with the effects of the earthquake, we simulated CSI population dynamics using a model that incorporated stratified earthquake-influenced survival rates λl (l = 0.00−1.00 at intervals of 0.25) under various scenarios. Under laissez-faire scenarios (median exploitation rate EMed) under low post-release survival rate SLow and all λl, the median number of hatchery-released fry Ht′ did not reach the target H* in 2014 and 2015. The probability Pj,t of not meeting the targets was 0.56−1.00 (2014) and 0.79−1.00 (2015). Meanwhile, with simulation of a low exploitation rate, SLow, and a higher λl (0.50), the Pj,t in 2014 and 2015 was 0.00−0.17 and 0.21−0.72, respectively. Under SMed and SHigh, Ht′ reached H* at λl (>0.50) regardless of El, and the cumulative catch varied primarily with Sl. Our results suggest that simulations can provide a method of predicting potential issues and can offer insight into strategies to minimize future problems. © 2015, Japanese Society of Fisheries Science.
Yamada H.,Iwate Biotechnology Research Center |
Ueda T.,Iwate Fisheries Technology Center |
Yano A.,Iwate Biotechnology Research Center
PLoS ONE | Year: 2011
Background: Pacific Krill (Euphausia pacifica) are small, red crustaceans, similar to shrimp, that flourish in the North Pacific and are eaten in Japan. Methods and Findings: We investigated the effect of a water-soluble extract of Pacific Krill on adipocytes and discovered that this extract suppressed triglyceride accumulation in adipocytes. Furthermore, the water-soluble extract of Pacific Krill suppressed the expression of two master regulators of adipocyte differentiation, peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT enhancer binding protein alpha (C/EBPα). C/EBPβ promotes PPARγ and C/EBPα expression, but the water-soluble extract of Pacific Krill did not inhibit the expression of C/EBPβ or C/EBPβ-mediated transcriptional activation. The Pacific Krill extract was more effective than a PPARγ antagonist in suppressing PPARγ and C/EBPα expression. Conclusions: These results indicated that the water-soluble extract of Pacific Krill was not simply a PPARγ antagonist, but that it prevented triglyceride accumulation in adipocytes by suppression of PPARγ and C/EBPα via a pathway that is independent of C/EBPβ. © 2011 Yamada et al.
Tanaka R.,National Fisheries University |
Naiki K.,Iwate Fisheries Technology Center |
Tsuji K.,Local Independent Administrative Agency Hokkaido Research Organization |
Nomata H.,Local Independent Administrative Agency Hokkaido Research Organization |
And 3 more authors.
Journal of Food Processing and Preservation | Year: 2013
Skinless fillets were prepared from Pacific saury Cololabis saira of varying degrees of freshness and then stored at -20 and -40C for 12 months to investigate the effects of lipid oxidation on quality deterioration. Peroxide value and 4-hydroxy-2-hexenal levels increased with storage temperature (-40<-20C) and corresponded with freshness. Peroxide value and 4-hydroxy-2-hexenal levels increased remarkably in frozen-thawed Pacific saury skinless fillets in comparison with raw Pacific saury; vitamin E was reduced for only 3 months. Lipid oxidation was inhibited when antioxitant-treated skinless fillets were stored at -20C for 12 months, immersed in 0.8% vitamin E or packed with an oxygen absorber. The 4-hydroxy-2-hexenal content was strongly correlated with propanal, a decomposition product of lipid oxidation that yields a fishy odor. © 2012 Wiley Periodicals, Inc.
Goto T.,Iwate Fisheries Technology Center |
Shibata H.,Kitasato University
Marine Pollution Bulletin | Year: 2015
Abundance and composition of anthropogenic marine debris were assessed on the basis of six bottom trawl surveys conducted on the continental slope off Iwate Prefecture, Pacific coast of northern Japan, in 2003, 2004 and 2011, and the temporal changes due to the Tohoku earthquake and tsunami in March 2011 evaluated. In 2003 and 2004, 54-94 items km-2 of marine debris, dominated by sea-base sourced items mainly comprising fishing gear and related items from adjacent fishing grounds on the continental shelf, were quantified. In the post-earthquake period, the density increased drastically to 233-332 items km-2, due to an increase in land-base sourced items generated by the tsunami. However, a major increase in abundance after the disaster, compared to the total amount of tsunami debris swept into the sea, was not found. Additional sources of land-based debris from the adjacent continental shelf are suggested in the present waters. © 2015 Elsevier Ltd.
Sadzuka Y.,Iwate Medical University |
Sugiyama I.,Iwate Medical University |
Miyashita M.,Iwate Medical University |
Ueda T.,Iwate Fisheries Technology Center |
And 4 more authors.
Biological and Pharmaceutical Bulletin | Year: 2012
Obesity is a major health problem showing increased incidence in developed and developing countries. We examined the effect of Euphausia pacifica (E. pacifica) (Pacific Krill) on high-fat diet (HFD)-induced obesity in C57BL/6 mice. No significant differences were observed in average food intake between the HFD and HFD with E. pacifica group, or the low-fat diet (LFD) and LFD with E. pacifica group for 18 weeks. The increased ratio of body weight in the HFD containing E. pacifica group was significantly reduced, being 10% lower than that with HFD group in the 18th week (HFD, 298.6±18.8% vs. HFD with E. pacifica, 267.8±16.2%; p<0.05), while the ratio for the LFD containing E. pacifica group was reduced by 4% compared with LFD group (LFD, 244.2±11.6% vs. LFD with E. pacifica, 234.1±18.0%). There were no effects of E. pacifica on total cholesterol levels in serum and liver, whereas the supplement of E. pacifica tended to decrease triglyceride levels in the HFD groups. The leptin level in serum was significantly decreased in the HFD group (p<0.01) by E. pacifica. The adipocyte area (1926±1275 μm 2) in the HFD containing E. pacifica group was significantly reduced by 20% (p<0.001) compared with the HFD group. These results suggested that E. pacifica supplementation in the diet is beneficial for the prevention of HFD-induced obesity. © 2012 The Pharmaceutical Society of Japan.