In order to evaluate agricultural production not only from economics but also from energy and load on environment, new indices using entropy were proposed, in which the concept of resource physics was applied. Poultry production was selected as a target system. Simulation of economics, energy and entropy was performed for different regions and housing types to demonstrate the new evaluation technique. Open type housing in warm climate was predicted to be most desirable from the view point of load on environment. However, for a colder climate the predicted desirable housing type was enclosed from the view point of production. The proposed indices which are combination of the load on environment and production, economics demonstrated the possibility to estimate a production system fitting to the region.

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Phosphorus (P) as phytic acid accounts for about 50-80% of the total P present in cereals and legumes. Due to the lack of phytase, it is hard for non-ruminants to digest this phytic acid, which is therefore excreted in the feces. Thus, inorganic P is added to the feed of non-ruminants to satisfy their requirements. However, most of this inorganic P is excreted in the feces and leads to environmental pollution. Recently, a new feeding technology which supplements phytase to the diets has been shown to effectively improve the availability of dietary phytate P and reduces the requirement of inorganic P added to diets. If this technology becomes widespread, inorganic P in feces of non-ruminants will be markedly decreased and reduce its value an available P source for crops.
The present report deals with the liberation of phytate-bound P in composts made with feces of cows, pigs, chickens and air-dried rice straw. It was found that with phytase of 1.25U/g and incubated under 55°C for 16 hours, increments of mineralized P were 14.3, 13.6, 9.15 and 46.2% in ratio over total inorganic P in composts from feces of cows, pigs, chickens and rice straw, respectively. This result suggests the possibility that phytic acids in feces or rice straw may be decomposed into inorganic P in the composting process by phytase added to diets.

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A starch-based biodegradable plastic reinforced with bagasse fiber was produced. Alkaline treated bagasse fiber was blended with a mixture of acetylated starch and Poly (ε-) caprolactone (PCL) as matrix, and was extruded as composites. The effects of treated bagasse fiber content, average length and distribution on tensile strength and water absorption were investigated. When the treated bagasse fiber was blended with the matrix at 0, 12.0, 15.0% (w/w%), the tensile strength of composite increased. However, the tensile strength at 21.5% was almost same as for the non-bagasse fiber composite, indicating that the average fiber length of this composite was shorter than the twice of the critical fiber length based on Kelly and Tyson. The water absorption was found to be reduced with increasing treated bagasse fiber content. This shows that the treated bagasse fiber was more hydrophobic than acetylated starch. The composite may be applied to the production of flowerpots or seedling pots in agriculture to replace polystyrene.

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Air-distribution characteristics was discussed within a windowless type weanling piggery by using three dimensional, isothermal, turbulent k-ε models introducing the term “volume porosity” and “surface permeability” which virtually presented the distributed solids such as porous ceiling and slotted floor in the piggery. The simulated results were compared with the observed data in the real weanling piggery, and then by using the simulation technique, air distribution in two pig raising rooms, having different ventilation systems such as negative and positive pressure, was compared from each other.

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Trace metals play an important role in methanogens growth and methane formation. In order to understand the requirement of trace metals for methanogens, the accurate measurement of intracellular trace metals of methanogens was required.
In this study, the washing effects of distilled water, physiological salt solution, phosphate buffer and EDTA mixture liquid on elimination of trace metals outside methanogen cells was investigated. Washed cells were pretreated by wet digestion method, and the content of trace metals were analyzed by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The variation in the content of intracellular ion measured was the smallest when phosphate buffer solution was used.
Damage of cells was observed by scanning probe microscopy. Furthermore, the damage of cells was relatively larger when cells were washed with distilled water. Because the washing process might cause the collapse of cells, we fixed the cell using glutaraldehyde before cell was washed. As a result, the fixation of cell was showed to be an effective method to reduce the measurement error in the analysis of intracellular trace metals.

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In order to evaluate the effect of changing temperature on maturation control of kiwifruit (var. Hayward) stored in modified atmosphere packages, storage tests were carried out. Two kiwifruits and a 10g sachet of ethylene absorbent (KMnO₄) were packed in 0.03mm thick low-density polyethylene bags and initially stored at 1°C for 3 weeks. The fruits were then removed and stored at different temperatures until the 8th week. The conditions of storage were: (a) weekly temperature changing between 1°C and 10°C; (b) weekly temperature changing between 1°C and 15°C; (c) weekly stepwise temperature increase of 1°C; (d) constant temperature of 5°C; (e) constant temperature of 10°C; (f) constant temperature of 15°C; and (g) constant temperature of 1°C, which is ordinary storage condition for comparison with changing temperatures. Due to variations in quality indexes of test samples, such as total soluble solids (TSS), titratable acidity (TA), firmness, weight loss, etc., at each sampling time after the 3rd week, the range of quality values at the end of storage were compared with the values of ripened kiwifruit on retail.
As a comparison of inner quality indexes of test samples and fruits ripened for retail, the respective values at storage temperatures of 1°C and 10°C, respectively, at 8 weeks ranged from 12.0% Brix and 14.2% Brix. These values were lower than 15.7% Brix for fruit on retail. On the other hand, the TA values of fruits stored at changing temperatures between 1°C and 15°C and between 1°C and 10°C at 6 and 8 weeks, respectively, were 0.9 and 1.0 citric acid g/100ml. Compared with TA value of 0.71 citric acid g/100ml for ripened fruit on retail, test sample were higher in TA content. The results show that fruits stored at changing temperatures ripened less than fruits on retail.
Moreover, the respective firmness values of fruits at storage temperatures of weekly increase of 1°C and constant temperature of 5°C were 10.8 and 16.8N/mm, respectively. These values were higher than firmness value of 4.8N/mm for kiwifruit on retail. This confirmed that test samples were firmer after storage due to scrubbing of ethylene gas in the polyethylene bags.
Weight losses at storage temperatures of 1°C and changing temperature between 1°C and 10°C at 8 weeks ranged from 0.5% to 2.0%. These values were lower than the upper limit of about 5% in fruits usually acceptable to consumers.

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