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81.
82.
The effects of corn dried distillers grains with solubles (DDGS) feeding on rumen fermentation and milk production in cows were evaluated using diets high in neutral detergent fiber (NDF, 45.9–46.6%). The control diet (Control) consisted mainly of hay, corn silage and concentrates. In the experimental diets, the concentrates were replaced with DDGS as 10% dry matter (DM) (10%DDGS) and 20% DM (20%DDGS). Eight cows were used for each 14‐day treatment period. Effect of DDGS feeding on DM intake was not significant. Ruminal volatile fatty acids and ammonia‐N at 5 h after feeding of 20%DDGS were decreased compared to Control, whereas protozoal count at 2 h after feeding of 20%DDGS was higher than that of 10%DDGS. Milk yield of cows fed DDGS diets was greater than that of Control, although percentages of milk protein and solids‐not‐fat were decreased by DDGS diets. The proportions of C10:0, C12:0, C14:0 and C16:0 in the milk fat decreased, and those of C18:0, C18:1, C18:2 and cis‐9, trans‐11 conjugated linoleic acid (CLA) increased markedly with elevated DDGS. Increase in trans‐11 C18:1 was observed in the rumen fluid at 5 h after feeding. These findings suggest that DDGS feeding enhanced milk yield, as well as CLA synthesis under a high dietary NDF condition.  相似文献   
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84.
Paddy and Water Environment - The topographical features of farmland stone walls that were damaged by two heavy rains and the 2016 Kumamoto Earthquake were studied. Topographical analyses were...  相似文献   
85.
Climate change will have significant impacts on the rain-fed rice production ecosystem, and particularly on the ecosystem’s hydrology and water resources. Under rain-fed lowland conditions, substantial variations among fields in grain yield are commonly observed, but a method that can account for field-scale yield variability to produce regional-scale yield estimates is lacking, thereby limiting our ability to predict future rice production under changing climate and variable water resources. In this study, we developed a model for estimating regional yields of rain-fed lowland rice in Northeast Thailand, by combining a simple crop model with a crop calendar model. The crop model incorporates the effects of two important resources (water and nitrogen) on crop growth. The biomass accumulation is driven by water use, whereas the nitrogen supply determines canopy development and thereby constrains crop water use. Accounting for the wide range of planting dates and the strong photoperiod-sensitive characteristics of rice varieties through the calendar model is an essential component in determining regional yield estimates. The present model does not account for the effects of mid-season drought or flooding, but was nonetheless able to explain the spatial and temporal yield variations at the province level for the past 25 years. Thus, it can be used as a prototype for simulating regional yields of rain-fed lowland rice.  相似文献   
86.
Rain-fed lowlands are major agricultural ecosystems used for rice production in Northeast Thailand. Developing a tool to assess the effects of variable water conditions on the regional scale yield is also important to predict the effects of climate change on food supply. To estimate regional yields, we need a simple but accurate measure of the crop calendar (i.e., the distribution of planting dates), which has a strong influence on grain yield. In this article, we modeled the dependence of the crop calendar on rainfall patterns based on a survey of the region’s farmers as a part of an effort to provide a stronger basis for regional yield estimates. Our survey, conducted in 11 provinces for 2 years, confirmed the existence of large windows for sowing and transplanting versus narrow windows for heading and harvesting for rain-fed lowland rice culture in all the provinces. Variable water, soil, and toposequential conditions in the paddy fields were responsible for the large sowing and transplanting windows, whereas the use of photoperiod-sensitive varieties explained the narrow windows for heading and harvesting. The crop calendar was well expressed as a function of cumulative precipitation from June onward. When the crop calendar model was combined with a simple phenology-based model that uses growing degree-days adjusted by a day-length factor, we could estimate the rice crop calendar under rain-fed lowland conditions with acceptable accuracy. The model described in this article will be combined with a crop growth model to improve regional yield estimates for rain-fed lowland rice.  相似文献   
87.
The purpose of this study was to measure the dynamics of serum α1-acid glycoprotein (AGP) concentration in dogs with various tumors, and to investigate the localization of AGP in some tissues using immunohistochemical staining. Sera were obtained from 171 dogs bearing tumors of various types. Serum AGP concentration was measured by single radial immunodiffusion. Tumors occurring in the liver and spleen were also investigated immunohistochemically using anti-canine AGP antibody. Mean serum AGP levels were 749 ± 602 mg/L in dogs with carcinoma (n = 39), 1,014 ± 971 mg/L with sarcoma (n = 18), and 887 ± 935 mg/L with round cell tumors (n = 46), all significantly higher than serum AGP level in healthy dogs (n = 137, 364 ± 106 mg/L). Mean serum AGP levels were significantly higher than in healthy dogs in complex mammary gland carcinoma (n = 5, 876 ± 721 mg/L), malignant melanoma (n = 7, 1,010 ± 821 mg/L), and hepatocellular carcinoma (n = 5, 936 ± 741 mg/L) among carcinomas, hemangiosarcoma (n = 5, 1,740 ± 1,323 mg/L) among sarcomas, and lymphoma (n = 19, 1,072 ± 965 mg/L) and histiocytic tumor (n = 6, 1,800 ± 1,387 mg/L) among round cell tumors. In an immunohistochemical investigation of AGP localization, both weak and strong staining for anti-AGP antibody were seen in hepatic tissue in dogs with primary non-tumorous lesions originating in the spleen (hematoma) and elevated serum AGP, but all tumor tissue in the spleen was negative. Among dogs with primary tumor lesions of the spleen (hemangiosarcoma) and elevated serum AGP levels, both weak, moderate and strong staining for anti-AGP antibody were seen in hepatic tissue, while strong positive staining was apparent in all tumorous tissue from the spleen. In primary tumor lesions in the liver (hepatocellular carcinoma), both moderate and strong staining for anti-AGP antibody were seen in normal hepatic tissue, and both weak, moderate and strong staining were seen in tumor tissues of the liver. AGP levels thus appear to be elevated in dogs with carcinomas, sarcomas, and round cell tumors. With some of these malignant tumors, localization of AGP in tumor tissue was seen.  相似文献   
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89.
The browsing habits of sika deer (Cervus nippon) in Japan have caused serious ecological problems. Appropriate management of sika deer populations requires understanding the different genetic structures of local populations. In the present study, we used 10 microsatellite polymorphisms to explore the genetic structures of sika deer populations (162 individuals) living in the Kanto region. The expected heterozygosity of the Tanzawa mountain range population (Group I) was lower than that of the populations in the Kanto mountain areas (Group II). Our results suggest that moderate gene flow has occurred between the sika deer populations in the Kanto mountain areas (Group II), but not to or from the Tanzawa mountain range population (Group I). Also, genetic structure analysis showed that the Tanzawa population was separated from the other populations. This is probably attributable to a genetic bottleneck that developed in the Tanzawa sika deer population in the 1950s. However, we found that the Tanzawa population has since recovered from the bottleneck situation and now exhibits good genetic diversity. Our results show that it is essential to periodically evaluate the genetic structures of deer populations to develop conservation strategies appropriate to the specific structures of individual populations at any given time.  相似文献   
90.

Background

Plant roots release a variety of organic compounds into the soil which alter the physical, chemical and biological properties of the rhizosphere. Root exudates are technically challenging to measure in soil because roots are difficult to access and exudates can be bound by minerals or consumed by microorganisms. Exudates are easier to measure with hydroponically-grown plants but, even here, simple compounds such as sugars and organic acids can be rapidly assimilated by microorganisms. Sterile hydroponic systems avoid this shortcoming but it is very difficult to maintain sterility for long periods especially for larger crop species. As a consequence, studies often use small model species such as Arabidopsis to measure exudates or use seedlings of crop plants which only have immature roots systems.

Results

We developed a simple hydroponic system for cultivating large crop plants in sterile conditions for more than 30 days. Using this system wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) plants were grown in sterile conditions for 30 days by which time they had reached the six-leaf stage and developed mature root systems with seminal, nodal and lateral roots. To demonstrate the utility of this system we characterized the aluminium-activated exudation of malate from the major types of wheat roots for the first time. We found that all root types measured released malate but the amounts were two-fold greater from the seminal and nodal axile roots compared with the lateral roots. Additionally, we showed that this sterile growth system could be used to collect exudates from intact whole root systems of barley.

Conclusions

We developed a simple hydroponic system that enables cereal plants to be grown in sterile conditions for longer periods than previously recorded. Using this system we measured, for the first time, the aluminium-activated efflux of malate from the major types of wheat roots. We showed the system can also be used for collecting exudates from intact root systems of 30-day-old barley plants. This hydroponic system can be modified for various purposes. Importantly it enables the study of exudates from crop species with mature root systems.
  相似文献   
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