The accessory genital glands of boars were examined with scanning electron and optical microscopies. The seminal vesicle consisting of a single layer of low columnar epithelium was identified as a compound tubular type. The epithelial cells were arranged generally in a form of a honeycomb. Some of the cells were either exfoliated or protruded. Long rodoform microvilli were visible on the surface of epithelial cells.
The prostate gland was identified as a compound tubular type composed of a single layer of tall columnar epithelial cells. Many but small secretory granules were found packed in the cytoplasm of each epithelial cell. The surface of the epithelial cells was almost spherical with partial proprusions.
The bulbourethral gland was identified as a compound tubular type. Its epithelium was composed of a single layer of columnar epithelial cells. The epithelial cells were arranged in a form a honeycomb. Their nuclei were small and were located at their base. The viscous secreta could be divided into the lipid-containing part and lipid-free part which was in a rectangular form with blunt angles and was combined with the other ones in every direction. In addition to the viscous glue-like substance, spherical substance with a diameter of approx. 20μm was noted at the tip of the glandular cells and in the ducts and was released by adhering to the surface of the glue-like substance.

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In order to prevent the delay of growth of growing-finishing pigs in winter, the influences of the increase in the amount and calory of feed, higher nutritional levels of feed, heating of pigpens and cold environments upon the rate of digestion of feed by swine were investigated in the present study.
1) The growth and weight gain were improved by the increase in the amount of feed, and growth, weight gain and feed conversion rate were improved by heating the pigpens. In the cold environments, the days required for the growing-finishing could be reduced by increasing the amount of feed by 20%, but there were hardly any differences in the feed conversion rate by the 20% increase. No adverse effects were observed by the increase in the amount of feed upon the results of slaughter or morphology or quality of carcass.
2) The growth and weight gain were improved by raising the calory of feed, and the feed conversion rate was also improved, but there were hardly any differences in the TDN required for gaining 1kg of weight in cold environments. Oils and fats of animal origin which were added for raising calory made the quality of meat poorer (especially that of the fat).
3) Higher nutritional levels of feed could improve both the weight gain and feed conversion rate, and required less TDN and DCP for weight gain of 1kg even in cold enviroments than otherwise.
4) The cold environments exerted no adverse effects upon the digestibility of feed except that of crude fibers, nor was there any difference caused in the nutritional value of feed by the cold envitronments.

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In order to clarify the mechanism of efficient utilization of legume silage by growing-fattening pigs, a series of experiments were conducted in the present study on the effects of varying ratios of legume silage in the whole feed upon the growth, morphology and, quality of carcass, limits of possible utilization, utility by classes of pigs, variations in consumption of high-calory feeds, ratio and classes of animal oils and/or fats added, classes of concentrate feeds, and optimum amounts of supply of the silage.
1. The maximum permissible limit of replacement of the formula feed by legume silage in growing-fattening pigs was 40% on air-dry matter basis taking the growth and weight gain into consideration.
2. There was no variation in utility of legume silage with the classes of swine.
3. Oils and fats of animal origin were most adequate for replenishing the calory which will become insufficient by the increased supply of the legume silage.
4. The acceptable ratio of addition of oils and fats of animal origin for replenishing the calory becoming insufficient by the increased supply of legume silage was in the range of 10-15% of the amount of the formula feed.
5. The fancy tallow was found to to effective among others as the oils and fats of animal origin to be added to the feed to replenish the calory becoming insufficient by the increased supply of legume silage.
6. Of the concentrate feeds to be used for improving meat quality which is affected by the combined feeding of legume silage with oils and fats of animal origin, the formula feed mainly containing barley (85.2%) was found to be the most effective for improving meat quality.
7. It was found to be recommendable for better growth and weight gain with varying ratios of legume silage by the steps of animal growth to keep its addition lower up until 40kg of body weight and then to raise the rate of addition of the legume silage during the weights of 50-70kg.
8. It was found to be important in any experiments to find the way for the swine to take as much legume silage as possible. It was found to be recommendable as a means for raising the rate of intake to supply the swine with the mixture of concentrate feed and the legume silage.
9. At the initial stage of the experiments, hay was prepared in advance for preparing the silage, but it was found out later that there would be no specific need to dry the legume in advance or to add any additive only if water is removed satisfactorily and application of a pressing weight and tight sealing are made carefully so sa to obtain silage of good quality.

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The present study was conducted to determine the number of bacteria adherent to various spots (doorway, disinfection tank, walking passage, window, ceiling, floor, manger, water-cup and paddock) of the sheds for breeding and growing-finishing pigs in our experimental farm. The following results could be obtained.
1) More adherent bacteria tended to be detected in the sheds for growing-finishing pigs than in the sheds for pigs used for breeding.
2) The largest number of adherent bacteria was detected on the floor of the pigpens, followed by those of doorway, manger, and water-cup in this decreasing order.
3) The number of adherent bacteria increased under the conditions of over a temperature of 20°C, humidity of over 70%, carbon dioxide concentration of over 0.1% and ammonia gas concentration over 10ppm.
4) A number of bacteria were detected at all times in the floor of pigpens, manger, and water-cups almost irrespective of the environmental conditions in the swine sheds.
5) Bacilli were found to be present in a large number in doorway, disinfection tank, manger and water-cups, while many cocci were detected in the ceiling and floor.

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The symptoms of estrus in time lapse which was induced by estrogens and pregnant mare serum gonadotropin (PMSG) in 40 prepuberal gilts were comparatively examined with those of the first estrus spontaneously induced in puberal gilts.
Forty prepuberal gilts at age of 160 up to 193 days received injections of varying doses of 0.2, 0.4 or 0.8mg of estradiol benzoate, or injections of other estrogens or PMSG, such as 0.2mg of estradiol benzoate plus, 5mg of estradiol dipropionate, 10mg of estriol, 2.5mg of diethylstil boestrol or 500IU of PMSG.
There were no significant differences in the layers of epithelial cells collected by biopsy of veginal vestibular mucosa accoring to varying doses of estradiol derivatives or varying estrogens or PMSG.
However, statistically significant differences could be noted at 3 of each test group in the changes of mucosal epithelial cell laper between the first estrus spontabeously induced and of estrus induced by estrogens and PMSG. The mucosal epithelial cell layer of the vaginal vestibule was the thickest amounting to 109.6μ at day 3 after the start of prepu beral stage of the gilts with the first estrus spontaneously induced, while the thickness in the PMSG group and that of the estrogen group at day 4 after the injection were 98.8μ and 85.5μ, respectively, which were the thickest of these groups.
Redness and swelling of valva were the most notable at day 3 in each group after initiating the experiment, and significant differences could found out among these groups in terms of the changes in time lapse. The variations in the widths of valva revealed that the width at day 3 was the maximum amounting to 4.2cm and 3.63cm in the group with the first estrus spontaneously induced and in the group with estrogens, respectively. The width of the PMSG group was at the peak of 3.57cm at day 4. No significant difference was observed between the width of valva at day 4 of each experimental group and those at day 5 of each of the experimental group, while that of the spontaneously induced initial estrus was the largest amoung other experimental groups.

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