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71.
72.
Yasuda K Hashikawa S Sakamoto H Tomita Y Shibata S Fukata T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(2):205-208
To evaluate the effects of a new synbiotic consisting of Lactobacillus casei subsp. casei (Lcc) and dextran (Dex) on milk production, a total of 58 Holstein dairy cows, which became pregnant and gave birth to calves at regular intervals and lactated steadily and continuously, were selected. The study had a completely randomized design, and the animals were divided into two groups. Group A was fed with a basic diet only, and Group B was fed with a basic diet supplemented with the synbiotic consisting of freeze-dried Lcc and mixed feed containing Dex for one year from August 2004. After supplementation with the synbiotic, milk yields and components of Group B were compared with those of Group A in the August, December of 2004, April and August of 2005. Milk yields of Group B were greater than those of Group A. There were significant differences (p<0.01 or 0.05) between these groups for all values. Furthermore, total amounts of fat, protein and solid non-fat in Group B significantly increased in comparison with those of Group A. In addition, the somatic cell counts of Group A significantly increased in August of 2004 and 2005 in comparison with those of Group B. Thus, the new synbiotic consisting of Lcc and Dex can increase the milk production of Holstein dairy cows throughout the year. 相似文献
73.
Fujiki M Shineha J Yamanokuchi K Misumi K Sakamoto H 《American journal of veterinary research》2007,68(8):827-833
OBJECTIVE: To investigate the effects of polysulfated glycosaminoglycan (PSGAG) treatment on serum cartilage oligomeric matrix protein (COMP) concentration, matrix metal-loproteinase-2 (MMP-2) and -9 (MMP-9) activities, C-reactive protein (CRP) concentration, and lameness scores in dogs with osteoarthritis. ANIMALS: 16 dogs with osteoarthritis and 5 clinically normal dogs. PROCEDURES: Dogs with osteoarthritis had a history of chronic lameness, and osteophytes were observed on radiographic evaluation of the affected joint. Polysulfated glycosaminoglycan was administered IM twice a week for a total of 8 treatments to all dogs with osteoarthritis and to clinically normal control dogs. RESULTS: Lameness scores after PSGAG treatment in osteoarthritic dogs improved in 12 of the 16 dogs. Serum COMP concentrations in osteoarthritic dogs were significantly higher than in control dogs before treatment. Lameness scores in osteoarthritic dogs decreased significantly after treatment, compared with before treatment. Lameness scores of 9 dogs with hind limb lameness improved significantly after treatment; these dogs had corresponding decreases in serum COMP concentrations. After treatment, serum COMP concentrations and lameness scores of 7 dogs with forelimb lameness remained high and were significantly higher than those of dogs with hind limb lameness. Serum MMP-9 activities of dogs with forelimb lameness were significantly higher than in dogs with hind limb lameness after treatment. CONCLUSIONS AND CLINICAL RELEVANCE: IM administration of PSGAG inhibited COMP degradation in dogs with osteoarthritis. Results indicate that decreases in serum COMP concentrations might be related to improvement in lameness after PSGAG treatment. 相似文献
74.
Akihiko Kotera Khang Duy Nguyen Toshihiro Sakamoto Toshichika Iizumi Masayuki Yokozawa 《Paddy and Water Environment》2014,12(3):343-354
We developed a crop scheduling model for rice cultivation in the Vietnam Mekong Delta (VMD), focusing on the adaptive behavior of crop planning to various water resource constraints. In addition, we also examined the effects of environmental change on rice cultivation in the last decade. In the VMD, multiple rice cropping is practiced under a variety of adverse water conditions, including flooding, salinity intrusion, and irregular monsoon rains. These environmental changes influence the durations of growing seasons and the number of crops per year, resulting in changes in productivity. To validate the performance of the model, we compared model estimates for the heading date and changes in leaf area index at nine sites with estimates of these parameters derived from MODIS satellite time series data for the period 2002–2006. The root mean square errors of heading date between the modeled and satellite data in the upper, middle, and coastal regions of the delta were 17.6, 11.2, and 13.0 days, respectively. Based on the model, we examined case studies to assess the changes in cropping cycles and crop failures in the VMD due to extreme flooding in 2000 and salinity intrusion in 2004 by applying evaluation indices defined by available period for cultivation (APC) and safe margin for cropping (SMC) which is defined as the marginal time between APC and the period required for cultivation. Findings of case studies suggested that a small difference in the SMC of the cropping pattern is critical to the stability and productive capacity of the rice crop. 相似文献
75.
Rie Matsumoto Natsumi Umezawa Masafumi Karaushi Shin-Ichi Yonemochi Kazuhiko Sakamoto 《Water, air, and soil pollution》2006,173(1-4):355-371
To understand the effect of the NH3 emissions from vehicles, the NH4 + bulk deposition and concentrations of gaseous NH3 and particulate NH4 + were measured at two sites in Saitama prefecture, Japan, one at the roadside of an arterial road (Kounosu), and the other in an agricultural area (Kisai). We observed that the NH4 + bulk deposition and NH3 concentration were significantly increased in Kounosu; the effect of NH3 emissions from vehicles was confirmed. NOx was a primary pollutant mainly emitted by vehicle exhaust in the vicinity of arterial roads, and the relationship between NO x and sum of gaseous NH3 and particulate NH4 + (T-NH4 +) was examined. The [T-NH4 +/NO x ] ratios in Kounosu ranged from 0.08 to 0.23 (average 0.15), and in Kisai they ranged from 0.16 to 0.67 (average 0.39). In Kounosu, the effect of vehicle exhaust was great, but seasonal variation was small. The contribution ratio of NH3 from vehicle emissions increased at low temperatures, while that from the non-vehicle emissions increased at high temperatures. 相似文献
76.
Monowar Karim Khan Kazunori Sakamoto Tomio Yoshida 《Soil Science and Plant Nutrition》2013,59(4):769-779
Abstract The response of peanut (Arachis hypogaea L.) to inoculation with vesicular-arbuscular mycorrhizal (VAM) fungi (Glomus etunicatum) and Bradyrhizobiurn sp. was studied in pots by the acetylene reduction activity (ARA) and ‘A-value’ methods. The soil used was a Light-coloured Andosol and the treatments consisted of the inoculation of VAM fungi only, inoculation of Bradyrhizobium only, dual inoculation of VAM fungi and Bradyrhizobium and control, under non-sterilized and sterilized soil conditions. In the non-sterilized soil the ARA and nitrogen fixation determined by the ‘A-value’ method increased significantly only by dual inoculation of VAM fungi and Bradyrhizobium at 100 days after planting (DAP), but no significant difference was observed at 70 DAP. In the case of dual inoculation, 75% of the nitrogen of the plant was derived from fixation whereas the plants inoculated only with Bradyrhizobium derived 68% of their nitrogen from fixation and the control plants, 64%. Amount of P in plant increased significantly only by dual inoculation with VAM fungi and Bradyrhizobium. In the sterilized soil a highly significant increase in the ARA was observed of the dual inoculation at all the sampling times. Nitrogen fixation determined by the A-value technique and N and P contents in plant also increased significantly by dual inoculation. Results obtained by the A-value method showed that plants with dual inoculation derived 68% of their nitrogen from fixation while the plants inoculated only with Bradyrhizobium, 38%. From our this study we conclude that nitrogen fixation as well as N and P contents in peanut increased significantly only by dual inoculation with VAM fungi and Bradyrhizobium. 相似文献
77.
78.
Aiko Nakano Hidetoshi Ikeno Toshifumi Kimura Hiromichi Sakamoto Masako Dannoura Yasuhiro Hirano Naoki Makita Leena Finér Mizue Ohashi 《植物养料与土壤学杂志》2012,175(5):775-783
Information related to the growth of fine roots is important for understanding C allocation in trees and the mechanisms of C cycling in ecosystems. Observations using a camera or scanner embedded in the soil enabled us to obtain continuous images of fine‐root‐growth dynamics. However, these methods are still labor‐intensive because the image analysis has to be conducted manually. We developed an automated method for tracking movement or elongation of fine roots using a sequence of scanner images. We also show how data obtained with these methods can be used for calculating fine‐root behavior. Two A4‐size scanners were buried in a mixed forest in Japan and images were taken continuously from within the soil. We preprocessed these images by extracting the fine‐root area from the images and developed an automated calculation plug‐in we named A‐root for tracking growth movement of the tips of fine roots. A‐root and manual‐tracking results were compared using the same images. The results show the A‐root and manual‐tracking methods yielded similar levels of accuracy. The average growth rate of 17 fine roots tracked using the program was 0.16 mm h–1. The observation of the direction of growth in fine roots showed the direction may be influenced by the original root's growth where the fine roots branched, distribution of soil particles, other roots, and the force of gravity. The A‐root analysis also suggested there may be an interaction between speed of growth and changes in direction of growing fine roots. 相似文献
79.
80.
Keisuke Kojiro Yuzo Furuta Makoto Ohkoshi Yutaka Ishimaru Misao Yokoyama Junji Sugiyama Shuichi Kawai Takumi Mitsutani Hiromasa Ozaki Minoru Sakamoto Mineo Imamura 《Journal of Wood Science》2008,54(6):515-519
To investigate the changes in microstructures of wood with elapsed time in the environment, CO2 adsorption onto dry wood was measured at ice-water temperature (273 K) for samples aged from 0.1 years to over 1000 years.
The micropore size distribution was obtained using the Horvath-Kawazoe method. Micropores smaller than 0.6 nm in wood decreased
in number with elapsed time in the environment, and a negative correlation was found between cumulative pore volume for pores
smaller than 0.6 nm and elapsed time in the environment. Cumulative pore volume in the 1000-year sample was almost half of
that in the 0.1- year sample. Micropores smaller than 0.6 nm in wood with a few decades or more of elapsed time increased
in number after rewetting and drying. Consequently, microstructures of wood with longer time elapsed in the environment were
considered to be more stable, because of longer-term thermal motion and possibly more repeated moisture adsorption and desorption
and/or temperature variation in the environment. 相似文献