In order to estimate the mass transfer coefficent of sweat on the body surface of cattle, the relationships between the length or diameter of the body segment and weight were investigated using Holstein cattle. On the basis of these relationships, the authors estimated the body segmental surface areas and set up experimental equations for the mass transfer of the body segmental surface using a one-eighth size model of a Holstein dairy cow smeared with naphthalene.
These experimental equations differed only to a very small extent with the cow's orientation toward the air stream. The mass transfer coefficient for the whole body surface of the cow in a standing posture could be approximated by an experimental equation for the neck, and its convective heat transfer coefficient was obtained by the Lewis relationship.

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The mass transfer coefficient of the trunk of a live cow was measured using a 10cm×10cm measuring band thinly smeared with naphthalene.
By the respiratory movement of the trunk, the values obtained were about 4.7 times larger than of an experimental model of the trunk in the previous paper.
Therefore, the mass transfer coefficient of the whole body could be considered to be about 2.7 times in 0.1m/s air velocity and 2.1 times in 0.2m/s air velocity larger than obtained in the model experiment of the previous paper.
In view of these results, it can be considered that thermal panting occurring during hot climate is available for loss of heat from the body surface.

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The authors examined the effect of several factors on breaking load (Pb) of a rice kernel by using the compressive test. Paddy showed the value as same as brown rice in a range of high moisture content, but there was the difference between paddy and brown rice in a range of low moisture content below 12%wb. The Pb of rice kernel was effected by the direction of accepted force, the least value was observed when the load was given in pararell with a long axis of kernel. The Pb of rice kernel was also effected by ripening period. In the variety difference, the Pb of Japonica type ordinary rice was larger than any other tested type in this study.

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The purpose of a series of studies beginning with this paper is to improve floors of cattle barns in increasing cow's productivity and establishing an economically reasonable barn's design.
In this paper, the authers performed kinetic analysises of phenomena on walk of Holstein cows to obtain basic data for the improvement. That is, by making three cows, whose weights were around 700kg, freely walk on a floor, various measurements were done; locomotor patterns of them, and changes of forces and the maximal pressure exerted by each cow against the floor during one stance phase.
The obtained results are summarized below:
1. Two peaks are found in the curves showing the change of vertical force produced by each forefoot or each hind foot during one stance phase.
2. In the three cows, the maximal and averaged vertical forces induced by each forefoot during one stance phase were 60% and 40% of the cow's weight, respectively, and those by each hind foot were 50% and 33%, respectively. The reason why the maximal and averaged forces by each forefoot are larger than those by each hind foot, respectively, can be considered owing to the fact that the distance of each forefoot and the center of gravity of the cow is smaller than that of each hind foot and the center.
3. The horizontal force produced by each forefoot along the direction of walk was nearly equal to that due to each hind foot. The force acted to the direction of progress in the latter half of a stance phase and to the opposite direction in the first half. The maximal and averaged forces were 10% and 5% of the cow's weight, respectively, in the both directions.
4. The horizontal force vertical to the direction of walk, which was produced by each foot, always acted to the outside of the cow's body. In addition, the both horizontal forces vertical to and along the direction of progress, which are applied by each forefoot, were almost same. The above facts show that cows considerably shift their centers of gravity on either side during their walking.
5. The maximal pressur exerted on the floor by each foot during one stance phase exceeded 10kgf/cm² at the spot trampled by the outside of the hoof.

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