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991.
992.
Gen Kume Toshihiro Horiguchi Akihiro Goto Hiroaki Shiraishi Yasuyuki Shibata Masatoshi Morita Makoto Shimizu 《Fisheries Science》2006,72(2):289-298
ABSTRACT: The seasonal distribution, age, growth and reproductive biology of marbled sole Pleuronectes yokohamae (Günther) from Tokyo Bay, Japan were studied. A clear seasonal distribution trend was observed, with P. yokohamae limited to the south of the bay in summer and expanding almost throughout the bay in other seasons. The formation and dynamics of hypoxic areas in the bay limited the northward distribution of P. yokohamae in summer. Age was determined by counting growth rings on otoliths; maximum ages were found to be 5 years for males and 6 years for females. The mean back-calculated length for females at each estimated age was greater than that for males. Growth of males and females was shown by the von Bertalanffy growth equations. Reproductive biology was studied on the basis of gonadosomatic indices and histological sections of gonads. The spawning season lasted from November to March, peaking in December and January. Sixty per cent of males at 1 year and all males ≥ 2 years had mature testes, whereas 6.7% of females at 1 year, 58.3% of females at 2 years, and all females ≥ 3 years had attained maturity. 相似文献
993.
Manabu Hattori Yoshifumi Sawada Michio Kurata Shinji Yamamoto Keitaro Kato & Hidemi Kumai 《Aquaculture Research》2004,35(9):850-858
Vertebral deformities in red sea bream, Pagrus major, remain serious obstacles to the improvement of seedling quality for its aquaculture. However, the causalities of the deformities remain unclear and prevention methods have not yet been established. In this paper, oxygen deficiency during somitogenesis was demonstrated to cause centrum defects (formerly called fused vertebrae in many cases), which are the major vertebral deformity in cultured red sea bream. An induction experiment of centrum defects was conducted by placing fertilized red sea bream eggs under low dissolved oxygen conditions (10.3–16.6%). The low oxygen treatment was carried out for five different developmental stages of embryo: two‐cell stage to blastula stage; gastrula stage; three to 10 somites stage; 11–17 somites stage and 18–24 somites stage. Oxygen deficiency during somitogenesis induced a high incidence of centrum defects. In contrast, it hardly induced centrum defects during the other stages. The dissolved oxygen concentration in the rearing water should be carefully regulated for fertilized eggs, especially during somitogenesis to reduce the incidence of vertebral deformities in the red sea bream. 相似文献
994.
Zaki Utama Yukako Okazaki Hiroyuki Tomotake Norihisa Kato 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(2):177-183
The present study investigated the effect of dietary tempe, a fermented soy product, on the colonic environment of rats fed high-fat (HF, 30 % fat; experiment 1) or low-fat (LF, 6 % fat; experiment 2) diets. Growing male rats were fed the experimental diets with or without 25 % tempe for 21 days. Tempe consumption slightly but significantly increased the growth of rats fed both the HF and LF diets (P?<?0.05). With both the HF and LF diets, dietary tempe markedly reduced a harmful fecal secondary bile acid, lithocholic acid (a risk factor of colon cancer) (P?<?0.05), and markedly elevated fecal mucins (indices of intestinal barrier function) and immunoglobulin A (IgA, an index of intestinal immune function) (P?<?0.05). With the HF diet, dietary tempe increased cecal acetate, butyrate, propionate, and succinate concentrations (P?<?0.05). Analysis of the profile of cecal microflora revealed lower Bacteroides and higher Clostridium cluster XIVa levels in the tempe group of rats fed the HF diet (P?<?0.05). Compared with the control group, the fecal activity of β-glucosidase was markedly higher in the tempe group (P?<?0.05), while that of urease was lower (P?<?0.05) with both the HF and LF diets. The present results suggest that tempe consumption modulates the colonic environment in rats. 相似文献
995.
Yasutomo Hoshika Makoto Watanabe Naoki Inada Takayoshi Koike 《Water, air, and soil pollution》2012,223(8):5017-5025
We examined the effects of ozone and elevated CO2 concentration in summer on the growth and photosynthetic traits of three representative birch species in Japan (mountain birch, Monarch birch, and white birch). Seedlings of the three birch species were grown in 16 open-top chambers and were exposed to two levels of ozone (6 and 60?nmol?mol?1 for 7?h per day) in combination with two levels of CO2 (370?C380 and 600???mol?mol?1 for daytime) from July to October. No adverse effects of ozone were found in the Monarch birch or the white birch, but elevated ozone in summer reduced branch biomass and net photosynthesis, and accelerated leaf abscission, in the mountain birch. Elevated CO2 promoted root development and thereby reduced the ratio of shoot dry mass (stem + branch) to root dry mass (S/R ratio) in the mountain birch and white birch. In contrast, there was no difference in dry mass between ambient and elevated CO2 for the Monarch birch, due to downregulation of photosynthesis. Studies of the combined effect of CO2 and ozone revealed that elevated CO2 did not ameliorate the effect of ozone on mountain birch in late summer. In considering the ameliorating effect of CO2 on ozone damage, it is necessary to take account of the species and the season. 相似文献
996.
Hiromi Kato Yasuhito Igarashi Yukiko Dokiya Yoko Katayama 《Water, air, and soil pollution》2012,223(1):159-167
Atmospheric carbonyl sulfide (COS) mixing ratios measured over 24 h during five summer campaigns (2003–2007) in a forest at
the foot of Mt. Fuji, Japan (35°21′ N, 138°43′ E; 1,300 m above sea level, a.s.l.) and at the summit (3,776 m a.s.l.) were
compared. COS levels were lower at the foot than at the summit during four out of five summer campaigns. The ratios of COS
mixing ratios at the foot of Mt. Fuji to those at the summit ranged from 0.7 to 0.9. These results provide evidence of biological
consumption of COS in the East Asian atmospheric boundary layer. We also measured the vertical profile of ambient COS below
the forest canopy. These data showed a clear gradient of COS mixing ratio: in the lowermost 1 m of the boundary layer, COS
mixing ratios decreased markedly downward. Two of the different kinds of vertical distribution of COS presented here support
the role of soil as a sink of atmospheric COS described by previous research using dynamic enclosure experiments. 相似文献
997.
Ma G Zhang L Kato M Yamawaki K Kiriiwa Y Yahata M Ikoma Y Matsumoto H 《Journal of agricultural and food chemistry》2012,60(1):197-201
β-Cryptoxanthin (β-cry), an antioxidant abundant in citrus fruits, plays an important role in the prevention and treatment of certain diseases, especially cancers. In the present study, to increase the content of β-cry in citrus flavedo, the effects of blue (470 nm) and red (660 nm) light-emitting diode (LED) lights on the accumulation of carotenoids and expression of genes related to carotenoid biosynthesis were investigated in the flavedo of Satsuma mandarin. The results showed that accumulation of β-cry was induced by red light, while it was not affected by blue light. The accumulation of β-cry under red light was attributed to simultaneous increases in the expression of CitPSY, CitPDS, CitZDS, CitLCYb1, CitLCYb2, CitHYb, and CitZEP. The results presented herein might provide new strategies to enhance the commercial and nutritional value of citrus fruits. 相似文献
998.
Makoto Mitsumori Hiroki Matsui Kiyoshi Tajima Takumi Shinkai Akio Takenaka Stuart E. Denman Christopher S. McSweeney 《Animal Science Journal》2014,85(1):25-31
Effect of the methane inhibitor, bromochloromethane (BCM) and dietary substrate, fumarate, on microbial community structure of acetogen bacteria in the bovine rumen was investigated through analysis of the formyltetrahydrofolate synthetase gene (fhs). The fhs sequences obtained from BCM‐untreated, BCM‐treated, fumarate‐untreated and fumarate‐treated bovine rumen were categorized into homoacetogens and nonhomoacetogenic bacteria by homoacetogen similarity scores. Phylogenetic tree analysis indicated that most of the fhs sequences categorized into homoacetogens were divided into nine clusters, which were in close agreement with a result shown in a self‐organizing map. The diversity of the fhs sequences from the BCM‐treated rumen was significantly different from those from BCM‐non‐treated rumen. Principal component analysis also showed that addition of BCM to the rumen altered the population structure of acetogenic bacteria significantly but the effect of fumarate was comparatively minor. These results indicate that BCM affects diversity of actogens in the bovine rumen, and changes in acetogenic community structure in response to methane inhibitors may be caused by different mechanisms. 相似文献
999.
Eiko Touno Makoto Kaneko Sunao Uozumi Hidenori Kawamoto Shin Deguchi 《Animal Science Journal》2014,85(1):46-52
Twelve sheep were used in a 3 × 3 Latin square design to evaluate the effect of substituting wheat bran with forage soybean silage in the diet on apparent digestibility and nitrogen balance. Forage soybean (Glycine max (L.) Merrill) was cultivated in a no‐till, no‐herbicide cropping system with Italian ryegrass (Lolium multiflorum Lam.) as a living mulch. Forage soybean and Italian ryegrass were wilted and ensiled in round bales without additives, respectively. The experimental diets were based on corn silage supplemented with protein sources (tow silages or wheat bran). The crude protein and the acid detergent insoluble protein contents of forage soybean silage were the highest among the protein sources. The apparent digestibility of crude protein and the nitrogen balance did not significantly differ among the diets. In addition, the phytoestrogen content of forage soybean silage was below the level at which animal reproductive performance would be negatively affected. These results suggest that forage soybean silage has comparable feeding value to wheat bran, and can be given at an inclusion level of 17% (dry matter basis) as an alternative protein source to wheat bran without adverse effects on digestion or nitrogen balance in sheep fed a corn silage‐based diet. 相似文献
1000.
Fuminori Tanihara Michiko Nakai Nguyen Thi Men Noriko Kato Hiroyuki Kaneko Junko Noguchi Takeshige Otoi Kazuhiro Kikuchi 《Animal Science Journal》2014,85(4):395-404
The zona pellucida (ZP) is considered to play important roles in the prevention of polyspermy in mammalian oocytes. However, in pigs we have shown that the presence of the ZP accelerates sperm penetration into the ooplasm during in vitro fertilization (IVF). In the present study, we investigated the effects of the ZP on sperm binding, acrosomal status, and functional exposure of IZUMO, a critical factor involved in sperm‐egg fusion, during IVF in pigs. We evaluated the numbers and acrosomal statuses of sperm binding to the ZP and oolemma, and being present in the ZP and perivitelline space (PVS) using ZP‐intact and ZP‐free oocytes. More sperm bound to the ZP than to the oolemma. The average number of sperm present in the PVS was 0.44?0.51 per oocyte, and all sperm had lost their acrosomes. The proportion of sperm that were immunopositive for anti‐IZUMO antibody was significantly higher after they were passing or had passed through the ZP. Furthermore, addition of anti‐IZUMO antibody to the fertilization medium significantly inhibited the penetration of sperm into ZP‐free oocytes. These results suggest that, in pigs, the ZP induces the acrosome reaction, which is associated with the functional exposure of IZUMO, resulting in completion of fertilization. 相似文献