We assessed loin eye area and thickness of fat layer of live swine bodies with the technic involving the scanner developed in Japan, in order to investigate various problems in the construction of the bodies and to study both the correlation between the construction and practical values of carcasses and the conditions for the photographing. Seventy Landrace pigs each weighing about 90kg were used for our experiment and the mean values of their body lengths were determined. The method for the photographing consisted in applying ultrasonic wave into live bodies, reflecting it onto a Braun tube, and photographing it with a polaroid camera. The photographing was made on the day prior to the slaughter and the construction was immediately figured for comparison with the samples of the same region which were left for 48 hours for cooling.
As a result, the following 6 aspects were noted:
1) The following five regions should be the principal ones for deciding the borderlines of the loin area on the basis of photographed records.
(1) Dorsal median line. (2) The third fat layer. (3) Borderline facing dorsal median line. (4) Upper face of costae. (5) M. iliocostalis thoracis and its outer borderline.
For evaluation of (3), the line in parallel with the dorsal median line with a consistent distance of 3.8mm and a line crossing the dorsal median line at an angle of 35° from the upper part of Mm. intertransversarii were used as auxilliary lines.
2) The correlation between the values determined with the ultrasonic wave and the practically determined values with carcasses amounted to r=0.935, which was significant with a level of 1%.
3) Another construction was figured by modifying the conditions of 1-(3) into a parellel line with a consistent distance of 5.8mm and a crossing line at an angle of 21°. The correlation in this case with the practical values of carcasses amounted to r=0.954 (P<0.01), which was slightly higher than the results of 2).
4) The accuracy of the values determined with the ultrasonic wave was extremely high, so that it could be realized that the loin eye area can be assessed by this means with live bodies.
5) The correlation of the thickness of the fat layer with the values amounted to r=0.861 (P<0.01).
6) The velocity of ultrasonic wave appropriate for this purpose was deemed to be 1740m per second for lean meat and 1450m per second for fat. The frequency could produce clear figures with 2MHz.

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In order to investigate the time of appearance of first estrus in swine, histoanatomical studies were made with various genital organs such as ovaries, oviducts, uteri, cervical canals, vagina, and vaginal vestibules.
The gilts used for the test were 214 Landraces, 12 Large Whites, 8 Hampshires, 5 Durocs, and 96 crossbreds.
1. In terms of correlation among various genital organs of the Landrace glits (in their ages of 170-180 days each weighing 90-95kg) prior to appearance of their first estrus, no significant correlation was noted between the weights of ovaries and the other genital organs. Significant correlations were noted between the sizes of follicles and oviducts, uteri, cervical canals, and vaginal vestibules.
2. With respect to the growths of various genital organs of gilts prior to appearance of the first estrus, the weights of uteri, cervical canals, and vaginae indicated rapid gains since their ages around 190-200 days after their births. In terms of weight gains, rapid gains were noted in the weights of cervical canals and vaginae from the time of body weight of approx. 110kg.
3. Changes in various genital organs following appearance of the first estrus were compared with those before appearance of the first estrus to find that there were no changes in the early follicular stage, while the weights of uteri and cervical canals gained double each and the weights of uteri and the other genital organs gained about 6 times and about twice, respectively. In terms of comparison between the luteal stage and ovulation stage in the weights of various genital organs, it was noted that the weights of ovaries gained at the luteal stage, whereas the weights of the other genital organs were reduced at the luteal stage.
4. With respect to time of appearance of the first estrus of gilts, the first estrus was initiated from around the age of about 170 days and the rate of the appearance of estrus increased by about 10% as 10 days each elapsed. At the age of about 250 days, the first estrus was appeared in about 90% of the gilts. The rate of the appearance of estrus increased by about 8-10% for weight gain of 5kg each. At the time with body weight of 130kg, the appearance of the first estrus was more than 90%.

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The mechanism of development of gastric ulcer in swine is so complex that its etiology and prophylaxis can not be termed as simple and easy. The aim of our present study lies in preventing the esophago-gastric ulcer by suppressing the pepsin activity under the conditions of feeding only the commercial compounded feedstuffs without spreading litters on the basis of the cage keeping which has been so far regarded as one of the most likely conditions for developing gastric ulcer in swine. Pepstatin which is a specific inhibitory substance to pepsin was added to feedstuffs and evaluations were made on its prophylactic effects against esophago-gastric ulcer, its suppressive effects upon pepsin activity, growths, clinical findings, hematological findings, carcasses, and various organs, obtaining the following results.
1. The prophylactic effect of pepstatin against gastric ulcer was not significant but a trend was more clearly noted for the substance to suppress the development of the ulcer in both groups of 50 and 100ppms than in the control group.
2. The effect of pepstatin upon the activity of pepsin was found to be significantly suppressive. A linear relationship was noted between the pepsin activity during fasting and the concentration of this substance added to feedstuffs.
3. The pepsin activity was found higher during fasting and lower following feeding, thus indicating strong effects by feeding upon the activity. Consequently, it was found as necessary for the slurry of feedstuffs under digestion to stay always in the stomach, and it was found effective for preventing the ulcer not to produce fasting conditions.
4. No specific effect of pepstatin was noted upon growths, clinical findings, hematological properties, and effects upon various organs. It was assumed unlikely that there should be any toxicity whatsoever through continuous administration of daily 0.7-5.7mg/kg of pepstatin.

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