[in Japanese]

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An experiment was carried out to induce the superovulation in mature rabbits (Japanese White Breed, more than 2 kg in body weight) by PMS and CG with progesterone pretreatment. The principal method is as follows; 1mg progesterone twice-daily for five days, subsequently 20 I.U. PMS twice-daily for five days followed by CG and mating. After two days' intermission, does were autopsied and the number of ovulation point, blood follicle, and follicle in the ovary, recovery of ova from the tube and the fertility of ova recovered were examined.
The results in June demonstrated that the superovulation was successfully induced by the preceding combined treatment with a satisfactory recovery and fertility of the ova ; no significant differences were observed between the oestrous and dioestrous group, except remarkable occurrence of the blood follicle in the former. In October and November, when the rabbit was in moulting, and the reproductive activity was to be lower, a little retardation in the response to the treatment in the number of both positive case and ovulation point was found. The pseudopregnant does(10th and 15th, when the treatment started, without progesterone administration), also indicated somewhat inferior results with the wider range of ovulation point number, and particularly, in 10 day, none; but in 15th day, moderate number of fertilized ova were obtained.
In conclusion, it can be said that the superovulation in rabbits is able to produce by PMS accompanied with progesterone pretreatment of which no work has ever adopted, though successful results hitherto were demonstrated only by the pituitary extracts or preparations. There are probably some differences according to the season of year in the response. The full data will be presented elsewhere adding the same kind of experiments carried on in March.

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Fructose and ascorbic acid in the seminal plasma of two rams were measured through a year to examine the seasonal variation and their relationship to spermatogenesis.
1. The concentration of fructose changed according to the breeding and non-breeding seasons appearing in ewes. That is, a noticeable increase was recognized during September-December (the breeding season), while extreme decrease was seen during March - July (the non-breeding season). January - February showed falling, while July - August showed rising tendency.
2. The present results suggested that there was seasonal variation in the secretory function of ram's sex accessory organs.
3. Judging from decrease in sperm concentration and index of motile spermatozoa and drop in pH of the semen during summer, passing hypo-spermatogenesis in the seminiferous tubes might be caused by the high temperature and humidity. However, there was no direct relationship between the phenomenon and the concentration of fructose.
4. The concentration of ascorbic acid tended to increase during January - June, and decrease during, July - December.

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Further experiment of out-season of lamb production by PMS pretreated with progesterone was carried out with 23 ewes (two of them was lost by accidents) at the University Farm. Two groups of experimental consisted of PMS (Exp. I) and PMS followed with LH-rich gonadotrophin treatment (Exp. II). Four ewes with the same condition as to age and previous lambing results were allotted to one of the non-treated control (Cont. I). The other control (Cont. II) with another eight ewes untreated was also employed to refer the result obtained from the treatment. The reason of setting the non-treated control was due to the fact of a tendency of early lambing within the year. The mode and the name of hormones used were progesterone, Luteogen-Tomoda 12.5mg twice-daily for three days, followed 2 days intermission, and then PMS, Peamex-Tomoda 1, 000 i u. Exp. II was further administered with LH, rich gonadotrophin Synahorin-Teizo 200 Rb. u. on the next morning of PMS injection. During oestrus last from 2 to 4 days after about 48 hrs. of PMS treatment, ewes were properly served with two rams once a day. Before and after the treatment the ewes were put on the pasture. Taking pregancy period for 145±5 days, lambing date between 18 th and 28th November, was accounted for a positive. Results in lambing were as followed: Exp. I, 3/5, Exp. II, 2/4, Cont. I, 0/3, Cont. II, 0/5. Assuming no differences existed between I and II, experimental and control sum up to 5/9 and 0/8, respectively. So that it was again demonstrated the successive percentage of nearly a half. Negative cases proved fertility of ewes and some of them showed early lambing. As was reported in the previous report, oestrus was not so prominent that holding ewes by head for mating was needed, and was variable in its length. Since the authors had obtained some cases of failure in inducing ovulation (unpublished data, '59) LH-rich gonadotrophin was introduced to test the effectiveness in the lambing result, however, no advantage seemed to be expected so far as in the final result.
Further studies aiming improvement in the result and producing Autmn lambs are on progress.

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Interrelations between production and deposotion of yolk proteins in the liver and ovarian follicles of the laying hen were investigated through NaCl-Ac turbidity test and by marking the rapidly growing follicles in the ovary (RGF) with colloidal Sudan III.
Though there were marked individual differences from hen to hen, the concentration of yolk precur-sors in plasma, expressed by the degree of NaCl-Ac turbidity, increased with increasing ovarian activity except hen No. 8 (A, Fig. 3) in which elevation of.plasma yolk precursor occurred when index of ovulation decreased from 100 to 45%.
The results of time study indicated that the day of skip in egg laying was often predictable when RGF if suitable size was absent in the ovary.

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Fructose and ascorbic acid in the seminal plasma of eight goats (6 Saanen breed and 2 Native breed) were measured through a year to examine the seasonal variation and in relation to spermatogenesis.
1. The seasonal variation of fructose concentration showed some difference between Saanen and Native breeds. In Saanen breed (5 out of 6 goats) it increased during breeding season while decreased during non-breeding season.
A noticeable increase was recognized during October-January and while the extreme decrease was observed during May-July. March-April showed falling while August-September showed rising tendency.
2. In Native breed having no breeding season in the female, there was no seasonal variation in the concentration of fructose, showing almost constant value through a year.
3. The concentration of ascorbic acid tended to increase during February-June, and decrease during July-January.

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