It has been well known that boar sperm are liable to fall into a state so-called "anabiosis", and that it takes 15 minutes to 2 hours warming and shaking to demonstrate their motility.
This study was conducted to examine the effect of the caffeine-slide (glass slide which was smeared with caffeine anhydrous) on the restoration of boar sperm motility. The preparation procedure of the caffeine-slide is shown in Figure 1. Undiluted boar semen was subjected to motility evaluation after 3 days' preservation in a test tube at 15°C.
Evaluation of motility was made microscopically at 38°C by placing 10 μl of semen between the pre-warmed slide and coverslip (1.8×1.8 cm).
Experiment 1. Using caffeine-slides which were smeared with various amounts of caffeine, motility evaluations were made at 15, 30, 60, 120 and 180 seconds after incubation on the microscopic stage at 38°C (Table 1). Caffeine-slides (0.52.0%) markedly stimulated sperm motility. Motility was increased as the amount of smeared caffeine was increased. However, the state of caffeine smeared on the slide was ununiform in the 2.0% slide. From these results, the use of a caffeine-slide which was smeared with 1.0% caffeine-ethanol solution appears to be adequate for the restoration of boar sperm motility.
Experiment 2. Semen samples were diluted with an equal volume of Ca⁺⁺-free KRP containing fructose (0.2%) or both fructose (0.2%) and caffeine anhydrous (0.1%). Three ml diluted and undiluted semen samples in glass tubes (φ: 15 mm, depth: 90 mm) were incubated in a water bath at 38°C without shaking. Motility evaluations were made on the semen samples at 0, 10, 20, 30, 60, 90 and 120 minutes after incubation using either caffeine-slides (1.0%) or untreated slides (Table 2). Regard-less of the dilution treatments, motility percentage was higher for caffeine-slides than untreated slides. In undiluted semen samples, tail to tail agglutination of sperm was characteristically induced by caffeine-slides (Figure 2).
Because of the simplicity of use and effectiveness for the restoration of motility, caffeine-slides may be applied to the evaluation of boar sperm motility in the laboratory and field.

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Sex ratios were studied in 13, 280 young of four strains of mice. All the strains belonged to the dd group. The results obtained are summarized as follows.
A shift of total sex ratio to male was observed in one strain. There was no shift of sex ratio when the four strains were examined as a whole. In each of the four strains, the rate of paternal and maternal individuals which showed a shift of sex ratio to either sex was in a range of 1.4 to 4.5 and 3.7 to 6.0 per cent, respectively. With regard to generation, a shift of sex ratio was recognized in one strain. In litter series and litter size, a shift of sex ratio was noticed in two strains. It was concluded that there might be no changes of sex ratio parallel with litter series or litter size.
A seasonal shift of sex ratio was seen in two strains. There were differences in sex ratio among the seasons in one strain. It cannot be said, however, that there is any relationship between sex ratio and season.
With regard to parental age, a shift of sex ratio was observed in two strains (paternal age only in the ddY strain). It was to male in the DDY strain and to female in the ddY strain. With regard to the parental age difference, no shift of sex ratio was seen in the DDY strain. With regard to maternal age at the time of first mating, no shift of sex ratio was recorded in any strain.
A shift of annual sex ratio was observed in two strains. It was to male in allthe strains.

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The effect of Hexestrol dicaprylate (H₈) on the biosynthesis of androgen in mouse testis was investigated by histochemical and biochemical procedures.
Mice of 60 days old were injected (i. m.) with 100, 500, and 2, 500 μg of H₈ dissolved in 0.2 ml sesame oil. After 30, 60, and 90 days, each testis was removed and studied on three oxidative enzymes by histochemical procedures.
Each 20 mg of testis removed on the 30th day after H₈ injection was incubated with [4-¹⁴C] progesterone (1.8 nmo1/0.1 μCi) and NADPH.
Radioactive metabolites were then separated by thin layer chromatographies and identified with the method of derivative formation and recrystallization to a constant specific activity.
Weights of the testes and accessory organs were significantly reduced in H₈ treated mice. The activities of glucose-6-phosphate dehydrogenase and of 3β-hydroxysteroid dehydrogenase seemed not to be affected by H₈ treatment in both interstitial and tubular elements. The activity of 17β-hydro-xysteroid dehydrogenase, however, was reduced in H₈ treated animals. Less testosterone was synthesized by testes obtained from the mice treated with 500 and 2, 500 μg of H₈. The decreased testosterone synthetic activity in these mice seemed to have been brought by the decreased activity of C_17-20 lyase and 17β-hydroxysteroid dehydrogenase. By a very high.dose of H₈, 17a-hydroxylase activity also seemed to be reduced considerably.

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The effects of a single injection of synthetic luteinizing hormone releas-ing hormone (LH-RH), PMSG and HCG in late pregnancy on delivery and post-partum ovulation in rats were investigated.
The hormones were injected subcutaneously (sc) after day 17 of pregnancy.
Ten μg/rat LH-RH prolonged pregnancy, while 10, 20 and 50 iu/rat PMSG and 20 IU/rat HCG caused premature delivery. Ten μg LH-RH and 20 IU HCG did not affect the number of shed ova and ovarian weight after delivery, whereas 50 IU PMSG in-creased both of them.
The time relationship between delivery and post-partum ovulation did not change with LH-RH, HCG or PMSG treatment.
LH level in serum increased within 1h (1046.5±237.70 ng/ml, Mean±SE) after 10 μg LH-RH treatment in late pregnancy and decreased to that of the control 2h later (121.5±19.23 ng/ml).
FSH level increased soon after the LH-RH treatment (983.0±73.70ng/ml) and remained in the high level as long as 3h after treatment.

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The effectiveness of intramuscular injection with PGF_2α followed by additional [Des-Gly-NH₂¹⁰, Pro-ethylamide⁹]-LH-RH (LH-RH-I) on the synchronization of estrus and ovulation were investigated in the experimental heifer (Exp. 1) and the grazing cow (Exp. 2).
1. In the Exp. 1, 5 out of 10 Holstein heifers in the luteal phase of the estrous cycle received an intramuscular (IM) injection of 10 mg of PGF_2α and the other 5 heifers received an IM injection of 20 mg of PGF_2a. Three out of 5 heifers in each group received an IM injection of 200 μg of LH-RH-I 42 h later (LH-RH-I-42) and the remaining 2 heifers received the same treatment 72 h later (LH-RH-I-72) after the PGF2a injection. The number of heifers showed standing estrus after the treatment were 3 of 6 heifers in LH-RH-I-42 and 1 of 4 heifers in LH-RH-I-72. All heifers in both trials ovulated 2836 h after the injection of LH-RH-I. The number of heifers conceived by artificial insemination during the period of synchronized estrus in the groups LH-RH-I-42 and-72 were 4 of 6 heifers and 4 of 4 heifers, respectively. Blood progesterone levels during the period of 24 h after the PGF_2α injection decreased slowly in the heifers given 10 mg of PGF_2α, as compared with those in the heifers given 20 mg of PGF_2α. In almost heifers, blood prgesterone levels after the injection of LH-RH-I were maintained as much levels at the time of the LH-RH-I injection and then the levels reduced to minimum level or near to it at the time just after ovulation.
2. In the Exp. 2, a total of 58 grazing Holstein cows in the luteal phase of the estrous cycle received an IM injection of 20 mg of PGF_2α and were alloted to three experimental groups; i.e. Group A (20 cows) and Group B (19 cows) received an IM injection of 200 μg of LH-RH-I after the PGF_2a injection. The time intervals from the PGF_2α injection to the injection of LH-RH-I in Groups A and B were 60 h and 73-74 hr, respectively. Group C (19 cows) received the PGF_2α injection alone. The percentage of the cows in estrus by 96 h after the PGF_2α injection and the average interval ± S. D. from the PGF_2α injection to ovulation were; 55.0% and 85.7 ± 8.7 h in Group A; 79.0% and 95.6 ± 8.6 h in Group B; 79.0% and 98.4 ± 16.9 h in Group C; respectively. The average interval ±S. D. from the LH-RH-I injection to ovulation were 17.2 ± 7.3 h in the cows that exhibited estrus before the injection of LH-RH-I, 29.8 ± 2.3 h in the cows that exhibited estrus after the injection of LH-RH-I, and 31.1 ± 2.3 h in the cows that showed silent estrus (quiet ovulation). The average interval ±S. D. from estrus to ovulation in both Groups A and B was 31.0 ± 5.5 h, as compared to 32.5 ± 5.9 h in Group C. The conception rates by artificial insemination during the period of synchronized estrus in Gropus A and B were 50.0% and 42.1%, respectively, compared with 70.6% in Group C and 53.8% in untreated controls.
From these results, it was considered that the most efficient time intervals from the injection of PGF_2α to the additional injection of LH-RH-I for the synchronization of estrus and ovulation may be between 42 h and 72 h, viz. 60 h.

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Adenylate cyclase, acid phosphatase and alkaline phosphatase were histochemically demonstrated in the placentae of swines 30, 60 and 90 days after service.
Adenylate cyclase was detected according to the method by W_AGNER et al., the composition of the medium being 0.5 mM of 5'-adenylyl imidodiphosphate, 2 mM of lead nitrate, 4 mM of magnesium sulfate, 2 mM of theophylline, 10 mM of sodium floride, 80 mM of tris-maleate buffer solution at pH 7.4 and 6% of dextran to make up the whole as 100%. After fresh sections were incubated in the medium for 90 min at 37°C, they were immersed in 1% yellow ammonium sulfate solution. A weak enzyme activity appeared in the cytoplasmic membranes of both uterineand chorionic epithelial cells from the swines at the different gestation stages. The fact that adenylate cyclase was demonstrated suggests that the adenylate cyclase-cyclic AMP system mediates the stimulation of gonadotrophins or prostaglandins to the steroid synthesis in swine placentae.
Acid and alkaline phosphatases were detected according to the method by B_URSTONE, the composi-tionof the medium being 5 mg of naphthol AS-BI phosphoric acid, 0.25 ml ofdimethylformamide, 30 mg of fast red violet LB salt, 15 ml of distilled water, and 15 mlof 0.2 M acetate buffer solution at pH 5.2 for acid phosphatase, while 15 mlof 0.2 M of tris buffer solution at pH 8.5 for alkaline phosphatase. Fresh sectionsfrom swine placentae were incubated in either of the mediums for 30 min at room temperature. Both the enzyme activities were demonstrated in the uterine epithelium at every stage, but none in the chorionic epithelium throughout the gestation period. The activities were moderate or strong in the placenta at 30 days of pregnancy, but gradually decreased as preg-nancy advanced.

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α-Fetoprotein (AFP) and albumin levels in sera of newborn calvis were measured by single radial immunodiffusion method reported previously. Serum total protein level was measured with a protin refractometer.
The level of AFP of newborns delivered with gesational age less than 270 days was significantly higher that of newborn with normal gestational age.
These results suggested that the AFP level may be a better indicator fo the maturity of newborn calf than the birthweight and any other serum protein level.

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In order to determine the efficacy of an analog of LH-RH (FUJINO et al.⁶) on fertility in dairy cows, single subctaneous injection of 100 μg LH-RH analog or vehicle only were given at the time of insemination. Pregnancy rate was higher in treated cows than in controls (75.0% and 61.3%, respectively), while the difference was not statistically significant.

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