In this study, the effects of process configuration on acidogenic performance were evaluated via system parameters such as volatile acid (VA) production, volatile solids (VS) degradation and particle size distribution under mesophilic conditions and an HRT of 20 days. Using fresh soybean meal or okara as substrates, two process configurations-the cascade process and the solid recycle process-were employed to perform the experimental estimation. An apparent first-order hydrolysis rate constant of 9.0×10^-3/d for the cascade process at pH values of 4.5-4.6, which was higher than that obtained by a previous study (7.2×10^-3/d), and 5.0×10^-3/d for the solid recycle process at a pH of 4.4, which was lower than that obtained in a previous study, were obtained. The apparent VS degradation ratio ranged from 9.6 to 16.5% and total VA (as acetic acid) from 10.8 to 16.7g/L. Occupying ratios for ionized VA in both process configurations increased from 27.5% to 30.8% for the solid recycle process and to 35.5% for the cascade process. The acetic acid ratios also were elevated from 86.0% to 94.3% for the cascade process and to 93.3% for the solid recycle process. As regards the distribution of VS particle size, the addition of milling balls caused the mechanical breakdown of the large particles whereas generation of soluble solid was not significantly affected.

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Thermal radiation falling on a pig housed in a building has a considerable heating effect on it and is one of significant factors affecting its comfortable conditions. The first step in most radiant heat transfer calculations is the determination of radiation configuration factors, which are also called angle, shape or view factors, between the pig and the surfaces of its surroundings. The configuration factors vary with the size or weight, posture and orientation of the pig, the distance from the pig to the surface, and the dimensions and direction of the surface.
The purpose of this investigation was to present configuration factors of growing-finishing pigs in a standing posture to vertical or horizontal rectangular planes on walls, ceilings and floors on the basis of their complex body shapes, when they can orient themselves to the planes at random. The configuration factor in this paper was the mean value of local configuration factors when the pig rotated from 0 to 360° at 15° intervals around a vertical axis through its center (that was the midpoints of the body width, body height and body length) for a given normal distance from the center to the plane and a given size of the plane, and therefore was not dependent on its orientation toward the plane. The local factor of the pig to the plane was numerically calculated by using the same procedure as author's previous studies; namely, three surface-models of standing pigs with live weights of 27, 65 and 88kg as subjects, and numerical analyses involving computer graphics such as the unit-sphere projection method were also used herein.
The percentage errors of the calculated configuration factors were estimated to be not larger than one percent by the theorem of summation for configuration factors and the law of propagation of errors. This led to the conclusion that the accuracy of the calculated factors was three significant digits or more.
The configuration factors of the pigs to rectangular planes on the wall located at a normal distance of 1.5m or larger and on the ceiling with a normal distance of not less than 0.5m were found to be evaluated with a sufficient degree of accuracy by the following well-known equation for the configuration factor φ of an infinitesimally small sphere to a rectangular plane:
φ=1/4πtan^-1(A/D)(B/D)/√(A/D)²+(B/D)²+1
where A and B are the side lengths in the rectangle, and D is the normal distance between the sphere and the plane. This equation was also available for determining the configuration factors of the pigs to rectangles on the wall with a normal distance of 1m or larger in the space between their centers and hooves. On the other hand, the equation was not available for evaluating the configuration factors to rectangular planes on the wall at normal distances of 0.5 and 1m, on the floor in direct contact with the bases of their hooves and on the floor below their hooves at normal distances of 0.5, 1 and 1.5m. Consequently, these factors were presented in graphical form as a function of one side length in the plane with the other side length and the normal distance as parameters.

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This paper describes the results from a one-year field survey at a dairy farm. The aim of the study has been to explore the relationship between thermal and aerial environment (i. e. weather conditions, thermal environment and air quality in barn) and animal behaviour in an open-type cattle house.
The examined cattle house was located near Chitose-City, Hokkaido, Japan, where the weather is relatively snowy and windy. The temperatures can be below -10°C in winter. A few days in summer, hot weather with temperatures above 30°C can be expected.
The field survey consisted of so-called 24-hour observations and morning observations carried out subsequent to the morning feedings. The 24-hour observations were carried out once in winter and once in summer. Four winter morning observations and four summer morning observations were made in the periods from December 1997 to February 1998 and from May to July 1998, respectively. On the basis of the results from the survey the following conclusions may be drawn:
1. The cows' preferences for feed, the stalls and the paddock were influenced by the seasons. In winter, some of cows preferred to lie in the stall at the time of feeding. The winter morning observations showed that the paddock and the stalls were almost used equally, while in the summer, the cows preferred to lie in the stall after eating.
2. Multiple regression analyses of the morning observation data showed that the predictor variables “time from feeding”, “indoor temperature”, “solar intensity” and “wind velocity components” could explain 60-70% of the variances in the cows' preferences for different places, i. e. eating area, stalls and paddock, in winter. While in summer, the predictor variables “time from feeding” and “solar intensity” could alone explain more than 90% of the variances of cows' preferences for eating area and stalls.
3. In order to obtain a better understanding about the air quality in open type animal buildings, further studies on variations in bacteria concentrations in a building under different ventilation conditions are desired.

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In order to reduce the addition of the inorganic phosphorus (Pi) to the diets of monogastric animals, it is expected that the addition of phytase to the animal diets to release Pi from phytate P in the diets will widespread in the near future. If so, the Pi content in feces and urine of monogastric animals fed with Pi additive-free diets will become remarkably low, and it will greatly reduce the nutrient value for crops. Then it will become important to promote the mineralization of phytate P in feces in composting process. We examined how extent phytase added to diets can decompose phytate P remaining in feces after being excreted.
Feces of pigs were fed with diets with or without phytase were held indoors for 40 days. The phytase activity was linearly decreased from 1, 070U/kg just after the excretion to 45U/kg after 40 days. While during 40 days, about a half of phytate P remaining in feces (1.26mgP/g) was decomposed, phytase activity had almost completely disappeared after 40 days. Thus, further decomposition of phytate P was not expectable.

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In greenhouses, the utilization of good-quality raw water and environmental protection are important problems for the favorable growth of seeds. In this study, stable granular ceramics of 0.8mm in diameter with electrical charges at the surface were developed, using the natural raw materials of silicate minerals at sintering temperature of 1200°C. Production of water with active functions was attempted by effective use of the ceramics with an efficient water treatment device in which the granular ceramics were fluidized in water. In the experimental results, for the ceramics-treated water, it was clear that the activities of water were obtained, that is, kaolin particles formed the larger flock in a wide range of PAC (Poly-Aluminum Chloride) concentrations, and the effective flocculation was confirmed with the increase in surface activity, and also the consumption speed of the chlorine was slow. The vigor of the melon seeds and the early growth for the ceramics-treated water were enhanced. Therefore, this water treatment device can contribute to improving water quality.

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Recently, various manure handling systems have been introduced into the dairy farming systems to reduce the pollution caused by livestock waste. However, the nitrogen load such as ammonia emission or the fossil energy consumption by the manure treatment might be increasing with the development of the livestock production, although the main purpose of the manure handling system is to recycle livestock manure efficiently. It is anticipated that the environmental points of views should be taken into consideration when evaluating manure handling systems.
In this paper, evaluation using two combined indexes, [Fossil Energy Input for manure handling/Net Agricultural Income] Ratio; (FEIm/NAI) and [Nitrogen Load by manure handling/Net Agricultural Income] Ratio; (NLDm/NAI) were conducted on three dairy farming systems having different manure handling systems; slurrygation system at a free stall dairy barn (system A), drying and composting at a free stall dairy barn (system B) and traditional solid and liquid separation system at a stanchion stall dairy barn (system C).
FEIm/NAI ratios for system A, B and C were 65, 17 and 13 [MJ/1, 000yen], respectively. NLDm/NAI ratios were 0.07, 0.32 and 0.06 [kgN/1, 000yen], respectively. These results show the environmental road caused by manure handling per agricultural income was comparatively smaller at system C having traditional manure handling system than at system A and B having advanced manure handling systems. From the evaluation of combined indexes in this study, it was indicated that the environmental load by advanced manure handling systems has not always reduced envirnmental load even though the advanced manure handling systems would be efficient and labor-saving.

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