Angiogram by soft-X-ray and giant histo-sections were used to investigate the interstitial vascular architectures and correlation between vascular reaction and histologic types of naturally occurring mammary adenocarcinoma in old C3H/HeJ female mice. The tumors were diagnosed as adenocarcinoma B type (Dunn's classification) composed of three different histologic types: solid, comedo, and papillomatous. From the findings of the angiograms, the interstitial vascular architectures of the tumor were classified into three patterns: sinusoidal, hypovascular, and hypervascular. The vascular patterns was characteristic in each histologic type and showed a close correlation with the intensity of tumor proliferation. The fine intratumoral angiographic investigation also made clear that necrosis of tumor cells and tissues seen in the histologic types showing marked proliferation was caused by hypoxia. Application of these methods to investigation of the fine vascular architecture in tumors may useful in research for adenocarcinoma.

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The relation between fertility and hormonal levels was studied in aging male rats. Reproductive ability was inspected at 30, 31, 59, 60, 93 and 94 weeks of age, and the serum hormone levels were determined by the radioimmunoassay. Reproductive ability decreased with aging (mating rates: 15/20, 11/20, 3/20 and 6/20 at 30, 31, 59 and 60 weeks, respectively) and no male mated at 93 and 94 weeks. Serum testosterone levels in males without reproductive activity were significantly lower than those in males with reproductive activity. LH and FSH showed the lowest level in 95 weeks. The highest value of LH was found at 60 weeks in males without reproductive activity having low testosterone levels. The highest value of prolactin appeared in 95 weeks which was three times higher than those in the other groups. The results suggest that the loss in the reproductive activity in aging rats starts with a decrease in libido, which is followed by a high gonadotropin and low testosterone condition, and accomplished under a low gonadotropin and high prolactin circumstance.

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The number of delivered offspring, corpora lutea and implantation sites was observed in an SPF colony of Wistar-Imamichi rats bred in a barrier system free of specified microorganisms and parasites and was compared with that of rats bred under conventional conditions. The litter size of 6142 SPF rats ranged from 1 to 20, averaging 12.4±0.04, a value significantly higher (P<0.001) than that of conventionally bred rats (11.0±0.04) . Although the number of corpora lutea was also higher in SPF rats than under conventional conditions, the number of post-implantation losses in SPF rats with less than 10 offspring showed a marked decrease compared with conventionally bred rats. These results show that the number of delivered offspring is higher in SPF rats than in conventionally bred rats and indicate that the increase in litter size is due to the increase in the number of corpora lutea and decrease in postimplantation loss of embryos or fetuses.

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Apparently healthy 242 colony-born cynomolgus monkeys (Macaca fascicularis) aged from 0 day to 90 days were examined for the findings of ocular fundus by using ophthalmoscope. One drop of mixed solution of 0.5% tropicamide and 0.5% phenylephrine hydrochloride was instilled into each eye of the monkey. Then, those monkeys were anesthetized with ketamine-HCl at the dose level of 10mg/kg B. W. Regular and fluorescein photographs were taken with Kowa RC-II ophthalmoscope-camera by using daylight typed color film. Following findings were obtained in each age class ; (1) Retinal color was salmon pink with 0 to 3-days-old neonates, salmon pink and blue to green with 7 days to 14-days-old animals and blue to green with 60-days to 90-days-old monkeys. (2) As regards optic disc, 0- to 14-days-old animals were observed to be light orange in color, and the infant aged more than 28-days showed orange color. (3) Retinal arteries and veins were lightly reddish in color with every age class. (4) Macular color was salmon pink in 0-day-old cases, slightly dark in 3-days-old neonates and very dark after 14-days of age. (5) Lightly retinal reflex was noted in 0- and 7-days-old animals. The reflex was observable in 14-days-old animals without any case of exception. (6) Retinal hemorrhages were recorded in 22 (67%) of 36 neonates born in natural condition and 10 (33%) of 30 neonates born by cesarean section. These findings will be useful as the criteria for ophthalmoscopic observations of the cynomolgus monkeys as laboratory use.

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A newly designed Y-shaped box was previously reported by authors to be useful for a screening test of visual abnormality in rats because of easy numerization and statistical analysis of the results. In the present paper, the relationship between the intensity of illumination and the negative phototaxic response were examined. The total selection rate for the dark area (total time of selecting dark area/total trials) of non-treated rats under 30lux illumination was 98% and identical with the result of those under 1600 lux. The selecting rates of non-treated rats under the illumination of 15, 10, 7.5, 5 and 1.25 lux were 95, 93, 89, 82 and 67%, respectively. On the other hand those of darkadapted rats one hour under 15, 7.5 and 5 lux showed 98, 95 and 92%, respectively. From these results, the critical intensities of illumination-unaffected selection rate for darkness in non-treated and dark-adapted rats were estimated at 30 and 15 lux, respectively. There was an obvious effect of dark-adaptation on the visual ability of rats. The selection rate of eyelid-sutured rats under 30 lux was 52%, an approximate theoretical value of true blindness, but it was 85% under 1600 lux. It is suggested that a more exact detection of visual abnormality would be possible under the critical intensity of illumination-unaffected selection rate for darkness.

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Antigenic characterization ofP. pneumotropicaderived from mice and rats were serologically investigated by use of hyperimmune rabbit sera against mouse strain M 1 and rat strain R 1 and absorbed sera m-1 and r-1 which were prepared by absorbing anti-M 1 serum with strain R 1 and anti-R 1 serum with strain M 1, respectively. All of 13 mouse strains employed were agglutinated with both anti-M 1 and anti-R 1 sera, but their agglutination titers with anti-M 1 serum were usually higher than those with anti-R 1 serum. Agglutination test of 13 rat strains with two antisera showed results converse to those of mouse strains. On the other hand, all the mouse strains were agglutinated with absorbed serum m-1 but not with absorbed serum r-1, while quite converse results were obtained with all the rat strains. Antigens reactive with the absorbed sera were remarkably destroyed by heating at 100°C for 1 hour and treating with 1 N HC1, suggesting to be capsular antigens of bacterial cells.

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The sexual maturation in the male house musk shrew, Suncus murinus, was investigated by weighing gonads, accessory sexual organs and various other organs, and measuring testosterone concentrations in the plasma from birth to 50 days of age. The histological and histochemical studies of the testis were also carried out. Testicular weight increased markedly from 10 days of age. On 15 days of age, the activity of Δ⁵-3β-Hydroxysteroid dehydrogenase (HSD) was detected in Leydig cells. In accordance with an increase of HSD activity, the concentrationre of plasma testosterone raised rapidly from 15 days of age and reached a peak on Day 30. Growth of prostate glands and seminal vesicles showed a sigmoidal pattern and their significant growth began from Day 25. Sperms were detected first in the seminiferous tubles on Day 28, and most tubles were filled with many sperms on Day 33. From these results, the begining of sexual maturation, i. e. puberty, of the male shrew is considered to be around Day 25. The weight gain of testes, accessory sexual organs and the body became slower on Day 40. The male animal of Day 40 could mate and impregnate the female. Therefore, the male shrew seems to attain to the sexual maturity between days 35 and 40.

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Newborn rats were marked directly by tattooing or branding on their body except for the cervical and dorsal area within 24 hours after birth. The results obtained were as follows. (1) . Tattoos (less than 2×2mm) and brands (circular, 3-4mm in diameter) on the skin were clearly recognizable during 21 days observation, and followed no deaths. (2) . The marking methods resulted in no differences in body weight gain or external differentiation when compared with untreated animals. (3) . Normal behavior was observed in the inclined plane test at day 7 or 21 after tattooing or branding. (4) . Newborn rats marked with tattoos or brands grew even under the care of foster mothers without any troubles.

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Isolation of Campylobacter jejuni (C. jejuni) from experimental dogs and monkeys was undertaken. C. jejuni was detected from 14.7% of the fecal samples obtained from beagles in a production colony, whereas 32% of newly imported beagles harbored the organisms. C. jejuni was isolated from 25% of the young and 3.9% of adult dogs in an animal center. The organisms were isolated from newly imported cynomolgus and rhesus monkeys at high frequencies (49.2% and 38.8%, respectively) . Almost all of the strains isolated were highly sensitive to erythromycin, chloramphenicol and gentamicin.

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Studies were conducted to compare the interferon (IFN) production of four strains of mice when injected with Newcastle disease virus (NDV), polyinosinic-polycytidylic acid (poly I. C), lipopolysaccharide (LPS) or purified protein derivative (PPD) . When injected with NDV, C57BL/6 and DDD mice generated higher levels of IFN than BALB/c and C3H/He mice. Upon injection with poly I. C or LPS, C57BL/6 and C3H/He mice produced higher levels of IFN than BALB/c and DDD mice. Differences in IFN production were also observed among BCG-sensitized mice of all four strains upon injection with PPD. C57BL/6 mice engendered the highest levels of IFN, while the C3H/He and DDD mice were intermediate in their response, with the BALB/c mice producing the least amount of IFN.

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Accessory spleen (AS) was observed in 19 out of 71 (27%) golden hamsters of APA strain autopsied in the Institute of Physical and Chemical Research. When these AS were examined histologically, clusters of pancreatic tissues, such as islets and acini, were detected in the parenchyma of one AS located in the tail of pancreas of a 15-week-old male animal. This heterotopic pancreatic tissue was considered to penetrate deep into the AS from the pancreas through the adhesion site without any connective tissue border during the ontogenesis.

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To investigate methods for the planned reproduction of the house musk shrew (Suncus murinus), increased reproduction was attempted from May through August, 1980 using 13 females and 13 males obtained from the breedng colony in the Laboratory of Animal Genetics, Eaculty of Agriculture, Nagoya University. As a result, a reproduction colony consisting of 128 females and 60 males was formed in September, 1981. This was followed by repeated selective culling until a planned reproduction system with monthly production of over 100 pups was established in December, 1981. The production results for one year, 1982, showed that among the 994 females mated, there was a gestation rate of 74.1%, a parturition rate of 89.8%, average litter size of 3.5, a weaning rate of 77.2%, and a productive index of 1.8. A total of 1, 780 weanlings was obtained and stable production throughout the year was achieved.

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The frequency of spontaneous anomalies among JW-NIBS rabbits in our laboratory is reported. The study was based on 1217 live fetuses obtained from 185 of an origin sample of 195 pregnant females; the remaining 10 (5.1%) aborted. Seven (0.57%) of the fetuses had the following external anomalies: multiple anomalies with craniofacial anomalies and thoraco-, gastroschisis (3 cases), microcephaly with open eyelids and microstomia (1), microphthalmia (1), anury (1) and brachyury (1) . Among 1213 fetuses, 2 (0.16%) had abdominal visceral anomalies: agenesis of gall bladder and hypoplasia of the ovary were each found in one animal. Head and thoracic visceral anomalies were found in 6 (1.73%) of 347 fetuses, and skeletal anomalies in 6 (0.69%) of 867 fetuses. 4.03 % of fetuses had 13 ribs.

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Apparently healthy 45 newborn Cynomolgus monkeys (Maraca f ascicularis) were examined for the persistence and disappearance of the hyaloid artery by using an opthalmoscope. On the day of birth, the hyaloid artery was observed in all the newborn animals. Between 21 and 45 days of age, the hyaloid artery faded without exception. The persistence of the hyaloid artery in the newborns and its disappearance during an early period of life can be regarded as a normal phenomenon in the developmental process of infant cynomolgus monkeys.

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[in Japanese]

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