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21.
The intake, digestibility, and grazing behavior of Hokkaido native horses were investigated in winter woodland with underlying Sasa senanensis. Twenty Hokkaido native horses were grazed in a woodland (8.52 ha) for 14 days in December (snowy; 20 cm of snow fall) and in November (non‐snowy) of the next year. Three mares (360 kg of average bodyweight) were used in each experiment. The fecal collection, used to investigate the intake and digestibility by the double‐indicator method, and behavioral observations were carried out for 24 h on the 6th day in each experiment. During the snowy and non‐snowy periods, the dry matter intakes of sasa foliage were 7.3 and 9.6 kg/d, respectively, which is 2.1 and 2.7% when expressed as a percentage of bodyweight. The apparent digestibility of nutrients and energy released during the snowy and non‐snowy periods were similar. The proportions of digestible energy intakes to maintenance requirement in the mares were 119 and 164% during the snowy and non‐snowy periods, respectively. Their bodyweight remained constant during the non‐snowy period; however, a slight loss in their bodyweight was observed during the snowy period. The duration of grazing on sasa foliage was 416 and 544 min/d during the snowy and non‐snowy periods, respectively, the daily grazing area of the mares during these periods was 2.0 and 5.1 ha, respectively. In other words, the area during the snowy period was smaller than that during the non‐snowy period (P < 0.05). Fallen snow, even with a depth of approximately 20 cm, inhibited the grazing behavior and intake of sasa foliage by Hokkaido native horses grazing in winter woodland pasture.  相似文献   
22.
B. E. Ubi    M. Fujimori    M. Ebina  T. Komatsu 《Plant Breeding》2001,120(1):85-87
The amplified fragment length polymorphism (AFLP) technique was applied to detect genetic variation in a sample of 47 plants representing 12 diploid cultivars of rhodesgrass. In this analysis, 50±91 easily scorable fragments could be detected in a single reaction. Each of the individual plants was uniquely identified by a combination of three primer pairs and an 80.2% level of polymorphism was obtained. Large amounts of genetic variation were present within all the cultivars. The results showed that AFLPs could be a robust technique for genome analysis in rhodesgrass with a promising potential as a breeding tool.  相似文献   
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In order to estimate dry deposition, deposition velocity calculation and concentration measurement were carried out in Niigata, Japan. Deposition velocities of SO2 and HNO3 for some surfaces such as coniferous forest, deciduous forest, agricultural land, and water were calculated taking into account diurnal variations of meteorological elements using routine meteorological data. Deposition velocities of fine and coarse aerosols were also estimated respectively. Concentrations of SO2, HNO3, sulfate and nitrate in fine and coarse aerosols respectively were measured from July to December in 1998 using filter pack and denuder methods. The results indicate that HNO3 dry deposition for the high aerodynamic roughness surfaces such as forests is quite large. It is suggested that sulfate and nitrate aerosols depositions as well as the gases depositions should be taken into account to estimate dry deposition of sulfur and nitrogen compounds. It is also indicated that dry depositions of sulfur and nitrogen compounds are unable to ignore compared with their wet depositions.  相似文献   
25.
An experiment was conducted to determine the effects of inclusion levels of potato pulp silage in concentrate (0, 15, 30 or 45%; on a dry matter basis) and roughage sources (rice straw or wheat straw) on finishing performance and carcass quality of cull beef cows. Sixteen Japanese Black (Wagyu) mature cull cows (490 ± 31 kg of BW) were used in this experiment. Increasing the levels of potato pulp silage in concentrate and roughage sources did not significantly affect feed intake in cows. In addition, the final body weight, daily gain and feed : gain ratio were not influenced by the inclusion levels of potato pulp silage in concentrate and the type of roughage. Increasing the inclusion levels of potato pulp silage in concentrate would probably decrease the marbling score. The L* values of the longissimus muscle (LM) tended to respond quadratically ( P  = 0.078) as the inclusion levels of potato pulp silage in concentrate increased, and was lowest for cows fed the concentrate which included 30% potato pulp silage. The a* and b* values of the LM and fat color were not affected by the inclusion levels of potato pulp silage in concentrate. No effects of roughage sources on finishing performance were observed.  相似文献   
26.
Amination of alkanes has generally required metal catalysts and/or high temperatures. Here we report that simple exposure of a broad range of alkanes to N-triflylimino-λ(3)-bromane 1 at ambient temperature results in C-H insertion of the nitrogen functionality to afford triflyl-substituted amines in moderate to high yields. Marked selectivity for tertiary over secondary C-H bonds was observed; primary (methyl) C-H bonds were inert. Addition of hexafluoroisopropanol to inhibit decomposition of 1 dramatically improved the C-H amination efficiencies. Second-order kinetics, activation parameters (negative activation entropy), deuterium isotope effects, and theoretical calculations suggest a concerted asynchronous bimolecular transition state for the metal-free C-H amination event.  相似文献   
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We studied the selectivity of a functional model of cytochrome c oxidase's active site that mimics the coordination environment and relative locations of Fe(a3), Cu(B), and Tyr(244). To control electron flux, we covalently attached this model and analogs lacking copper and phenol onto self-assembled monolayer-coated gold electrodes. When the electron transfer rate was made rate limiting, both copper and phenol were required to enhance selective reduction of oxygen to water. This finding supports the hypothesis that, during steady-state turnover, the primary role of these redox centers is to rapidly provide all the electrons needed to reduce oxygen by four electrons, thus preventing the release of toxic partially reduced oxygen species.  相似文献   
29.
The possibility of persorption of bovine serum albumin (BSA) molecules from mucous epithelial cells and its mechanism were investigated in rats orally pre-immunized by BSA for 14 consecutive days. In the small and large intestines, both the BSA antigen (BSA-Ag) and its specific antibody (SpAb) were absorbed by the epithelial cells at the late apoptotic stage (ApoEp), and were subsequently transcytosed by membranes of the small vesicles. The basal cytoplasms containing highly-concentrated BSA-Ag and SpAb were occasionally fragmented into small cytoplasmic droplets that were secreted into the lamina propria. In Peyer's patches, both BSA-Ag and SpAb were more actively absorbed and transcytosed toward the dome area by the ApoEp of the dome apex than by the M cells. BSA-Ag and SpAb were finally persorbed into the portal blood and lymph, but were never secreted into the bile. They were also engulfed by macrophage-like cells in the villous lamina propria, mesenteric lymph node and spleen, and by hepatocytes in the liver. These findings suggest that sensitized soluble luminal antigens are taken up by ApoEp in the small intestine and are finally persorbed into the peripheral blood. The uptake of luminal antigen might be mediated by its luminal SpAb.  相似文献   
30.
The effects of grazing and supplemental protein concentrations, provided during the grazing period, on subsequent finishing performance and carcass quality were investigated. This experiment was carried out using 15 Japanese Black cattle (Wagyu) steers. The steers were fed as follows: (i) grazing supplemented with moderate protein concentrate (GMP) (18% crude protein (CP); dry matter (DM) basis) before finishing, followed by feeding in a barn until slaughter; (ii) grazing supplemented with low protein concentrate (GLP) (14% CP; DM basis) before finishing, followed by feeding in the barn until slaughter; and (iii) no grazing before finishing (NG). From the end of the grazing season to the end of the growing period, the GMP and GLP steers were managed in the same way as the NG steers. All of the animals were fed the same diet in the finishing period (9 months to 28 months). None of the three treatments affected the average daily gains. For all treatments, chilled carcass weights were more than 450 kg and did not differ significantly among the groups. The longissimus muscle areas in the grazed steers were numerically larger than in those receiving the NG treatment. Fat thickness was significantly greater (P < 0.05) in the NG steers than in the grazed steers. The intramuscular fat and marbling scores were not affected in the grazed steers. In conclusion, the carcass quality of grazed steers was similar to that of the NG steers at a similar final age, and the quantity of meat in the NG steers would be less than that of the GMP and GLP steers. Therefore, spring‐born Wagyu steers should be grazed using the GLP supplement before fattening.  相似文献   
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