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91.
92.
Seiichi Oyamada Yasuhiro Ueno Mitsutaku Makino Koji Kotani Hiroyuki Matsuda 《Fisheries Science》2009,75(2):273-283
In the middle of the 1990s, Pacific saury fishery vessels began to install “size separators” to selectively land large-size
class fish with a higher price. Contrary to expectations, this resulted in removal of the separators in 2006 because fishers
believed the separators had contributed to price collapses in the 2000s. The intent of this paper is to investigate the effects
of separators on both the fishery economy and stock of Pacific saury by simulating population and economic models under a
single framework. For this purpose, we developed (1) an age-structured population dynamics model with stochasticity, and (2)
an economic model spanning both price and inventory dynamics with stochasticity, in which each set of model parameters were
estimated on the basis of time series data. In a 10-year simulation, the harvest quota was set constant from 20,000 to 400,000 t
at intervals of 20,000 t, and the effects of separators were incorporated by controlling the catchability of 0-year-old fish.
We found that separators increase the expected yield and reduce the deficit risk for harvests of 140,000 t and smaller. However,
separators have the opposite effects for harvests of 160,000 t and larger. 相似文献
93.
Nopporn Manajit Takafumi Arimoto Osamu Baba Seiichi Takeda Aussanee Munprasit Kamolrat Phuttharaksa 《Fisheries Science》2011,77(4):447-454
The Japanese type of set-net, Otoshi-ami, was introduced to Thailand in 2003 with the aim of assessing its feasibility as
a sustainable coastal fisheries management tool for the empowerment of coastal fishers’ communities. All preparations for
constructing and installing the set-net in the coastal waters off Mae Rumpheung beach, Rayong Province, Thailand, were carried
out by local fishers, with technical advice and support from national and international institutions. The gear was modified
and developed to suit the conditions of the fishing ground and target species. Data on the catch and sales trends in Rayong
using the set-net were collected for 7 years for statistical analysis; during this period, the gear design and marketing strategies
were improved. Simulation analysis for evaluating the cost–profit bases was conducted to establish a model for set-net technology
transfer in Southeast Asia, based on differing numbers of fishers and operation days. The simulation results show the required
size of the average daily catch to cover the total cost according to the average unit price, where the economic return point
is an average catch of 128 kg, based on a unit price of 25 Baht/kg (0.83 USD/kg), with ten fishermen and a daily operation
cost of 3,200 Baht (USD 106.17). 相似文献
94.
Matsuu A Kawabe A Koshida Y Ikadai H Okano S Higuchi S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(8):893-897
To identify the incidence of Babesia gibsoni (B. gibsoni) in Aomori Prefecture, northeastern Japan, dogs with acute B. gibsoni infection were investigated at the Animal Teaching Hospital, Kitasato University, between April 2002 and March 2003. Eighteen dogs with acute B. gibsoni infection were recognized; they were all male dogs of the fighting dog breed Tosa. Their platelet counts were below normal and their packed cell volumes (PCVs) were at various levels. We collected blood samples from 141 Tosa dogs from Aomori Prefecture and used polymerase chain reaction assay to investigate the incidence of subclinical B. gibsoni infection. We also looked into the serological abnormalities associated with thrombocytopenia or anemia in subclinical infection. Forty-one of 87 dogs (47.1%) with histories of dog fighting, and one dog of 54 without a history of dog fighting were positive for B. gibsoni; that is, 42 of 141 dogs (29.8%) showed a positive result. The mean platelet counts of dogs with subclinical infection were significantly lower and levels of anti-platelet IgG were significantly higher than levels for dogs without infection. Anti-erythrocyte membrane IgG levels were significantly higher in dogs with subclinical infections, although mean PCVs were not significantly different. Tosa dogs from Aomori Prefecture, Japan, were highly infected with B. gibsoni subclinically and this pathogen might be successfully transmitted during dog fighting. Dogs with subclinical infections were at risk of chronic thrombocytopenia, which may be due to autoimmune mechanisms. 相似文献
95.
Okuno S Kobayashi T Orito K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1265-1268
We conducted combined electrophysiological examinations including F-wave, motor nerve conduction velocity (MNCV), spinal cord-evoked potential (SCEP), and needle electromyography (EMG) in two cats involved in traffic accidents that consequently developed hind limb paralysis caused by lumbar hematomyelia. F-wave could no longer be elicited within 3 days after the accident, and the MNCV and compound muscle action potential (CMAP) amplitude decreased in a time-dependent manner, with CMAP no longer being evoked after 7 or 8 days. EMG showed abnormalities such as fibrillation and positive sharp waves after 6 to 8 days. These results suggest that such combined electrophysiological examinations may provide objective, quantitative data for motor nerve dysfunction in cats with lumbar hematomyelia. 相似文献
96.
Changes in peripheral blood mononuclear cells after calving in lactating cows with serious decrease of body weight before and after calving 总被引:1,自引:0,他引:1
Ohtsuka H Kase H Ando T Kohiruimaki M Masui M Watanabe D Hayashi T Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(2):153-158
The aim of this study was to clarify the hormonal and immunological changes in periparturient dairy cows with excessive weight loss following calving. We analyzed leukocyte populations and the peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, IL-4, growth hormone (GH)-receptor (R) and insulin -R and measured the GH and insulin concentrations. Ten dairy cows fed in one herd were used in this study and were divided into two groups. Five cows that experienced loss of body weight following calving of over 10% comprised the Weight Loss Group, and the remaining five cows, which experienced loss of body weight of 5% or less following calving, served as the Control Group. The Weight Loss Group had high serum cholesterol and low blood urea nitrogen levels compared with the Control Group throughout the period of observation. In regard to the leukocyte populations, there were significantly fewer CD4(+)CD45R-T cells in the Weight Loss Group 1 to 2 months after calving compared with the Control Group. The percentage of IFN-gamma/IL-4 among PBMCs in the Weight Loss Group tended to be lower than in the Control Group throughout the observation period. In the Weight Loss Group, the levels of GH-R during month 2 were lower than in the Control Group. We concluded that excessive loss of body weight in dairy cows following calving is associated with depressed cellular immune function. 相似文献
97.
Wada K Hashiba Y Ohtsuka H Kohiruimaki M Masui M Kawamura S Endo H Ogata Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(2):193-196
The effects of mycotoxins on mitogen-stimulated proliferation of bovine peripheral blood mononuclear cells (PBMCs) were investigated. Aflatoxin B(1) (AFB(1)), deoxynivalenol (DON) and zearalenone (ZEN) were added to cultures of PBMCs, and the proliferation responses were measured using MTT bioassays. Suppression of the proliferation of calf PBMCs by AFB(1) and DON was significantly stronger than that of cow PBMCs, whereas there were no differences in suppressive effects on PBMCs from Holstein and Japanese Black calves and cows. The suppressive effect was greatest in the order of DON, AFB(1) and ZEN, and the effects of DON and AFB(1) seemed to be dose-dependent. The results suggest that some mycotoxins directly suppress proliferation of bovine PBMCs. 相似文献
98.
99.
100.
Mae N Makino Y Oshita S Kawagoe Y Tanaka A Aoki K Kurabayashi A Akihiro T Akama K Koike S Takayama M Matsukura C Ezura H 《Journal of agricultural and food chemistry》2012,60(4):1013-1019
The storage of ripe tomatoes in low-O(2) conditions with and without CO(2) promotes γ-aminobutyric acid (GABA) accumulation. The activities of glutamate decarboxylase (GAD) and α-ketoglutarate-dependent GABA transaminase (GABA-TK) were higher and lower, respectively, following storage under hypoxic (2.4 or 3.5% O(2)) or adjusted aerobic (11% O(2)) conditions compared to the activities in air for 7 days at 25 °C. GAD activity was consistent with the expression level of mRNA for GAD. The GABA concentration in tomatoes stored under hypoxic conditions and adjusted aerobic conditions was 60-90% higher than that when they are stored in air on the same day. These results demonstrate that upregulation of GAD activity and downregulation of GABA-TK activity cause GABA accumulation in tomatoes stored under low-O(2) conditions. Meanwhile, the effect of CO(2) on GABA accumulation is probably minimal. 相似文献