The allelic frequencies at 6 isozyme loci (Es-1, Es-2, Es-3, Es-4, Es-Si and Amy-1) were examined in 4 outbred Wistar strains and additionally 2 SD strains as controls. From the allelic frequencies, the averages of the heterozygosities in individual strains and the geometric genetic distances between every pair of all possible strain combinations were calculated. The averages of the heterozygosities in 2 SD strains were both intermediate (around 0.2) and the genetic distance between them was rather short. But among the Wistar strains, the averages of the heterozygosities were highly variable and the genetic relationships among them were very variable in their genetic distances. From these results, it was suggested that the outbred Wistar strains were different each other in their genetic constitutions and that no suggestion was obtained to descriminate genetically the Wistar strains from the SD strains.

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Rearing and breeding scores were compared between groups of mice (JCL: ICR and ddN strains) raised with two different types of automatic water-supply systems ; the Japanese type and the American type, using manual water-supply system as control. The mice raised with the manual water-supply system were superior in body weight gain as compared to those with two automatic water-supply systems. As to the survival rate, however, the manual water-supply system and the Japanese type gave better results than the American type. As to weanling rate in the breeding test, the manual water-supply system gave somewhat better result than either of the two automatic types. Accidental water leaks, which are serious problems of automatic systems, occurred frequently only when the American type was used. Only one defect of the Japanese type revealed was that it was unfavorable for mice with smaller size (e. g., young ddN mice), resulting in lower body weight gain as well as lower breeding scores.

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The incidences of spontaneous fetal anomalies in coccidium-free Japanese white rabbits bred and kept in our laboratories are reported. Live fetuses were removed from 87 (95.6%) out of 91 maternal animals examined, totaling 538 (295 males and 243 females) . Of them, 9 fetuses (1.7%) showed external and visceral abnormalities such as hydrocephalia (5 cases), short tail (2), anophthalmia (1) and talipomanus flexa (1) . Skeletal abnormalities were found in 7 (1.7%) of 424 fetuses examined.

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A total number of 1549 dogs from Miyagi Prefecture and the north coast area of Fukushima Prefecture were surveyed during a year from December 1976 to November 1977 for Brucella canis (B. canis) . 173 of 1549 dogs (11.2%) were sero-positive to B. canis, and B. canis was isolated from 55 of 148 dogs examined, giving more than 3.6% for total 1549 dogs. The positivity were higher than that have been reported from other areas. The results of the morphological and biochemical studies for isolates were similar to the reference strain RM6/66, and they were identified as B. canis. No significant difference in sero-positive rate was found between male and female, but isolation rate was higher in female than in male. B. canis was isolated most frequently from the uterus and the spleen of both sexes. The importance of urine and milk as a source of infection was discussed as well as the role of infected focus at non gravid uterus for abortion and fetal infection. A case supposed to be a vertical infection was described also.

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Swine gastric ulcer was investigated from ecological, clinical and pathological view points for its availability as a disease model of human gastric ulcer. Marketed pigs from a piggery showed a high (50%) incidence of gastric erosionulcer of non-glandular region in contrast to pigs from another pig breeder showing no incidence. Responsibilty of fineness of growing and fattening diets for the high incidence in the former group was suggested by an experiment rearing pigs with a ration either fine or coarse particle size. Time-course pursuing of clinical, including gastroscopy, and pathological changes of these pigs revealed an early onset, at an age of 2 months, of the gastric lesion which was led to chronic ulcer at 6 months of age or older. Although the swine gastric ulcer had a common feature to be a peptic ulceration as in human gastric ulcer, being the site was non-gastric juice-producing region having a chance to be immersed with the peptic secretion, the privileged site of ulceration in swine stomach differed from that in human's, and thus, mechanism of generation of ulcer seemed differ between them. Despite, chronicity of the disease course and histological changes characterized by four layers of the ulcerated wall and presence of vascular and nervous lesions indicated a certain similarity to human chronic ulcer suggesting availability of the disease for investigation of some aspects of pathogenesis of chronic, indurated human gastric ulcer. In addition, modifiability of the disease process by means of changing fineness of the deit could have taken advantage than other experimental gastric ulcer produced by various artificial means.

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During a period from 1973 to 1978, 392 and 225 lots including 12, 232 mouse and 8, 044 rat individual sera, respectively, were examined for antibodies to murine hepatitis virus, Sendai virus, Bordetella bronchiseptica, Mycoplasma pulmonis, Tyzzer agents, Salmonella typhimurium and Corynebacterium kutscheri. Of mouse lots 94.5% and 39.3% from breeder and user colonies, respectively, were negative for all antibodies examined as well as 31.6% and 17.2% of rat breeder and user colonies, respectively. Among positive lots from mouse users, high positivity rates were seen with Sendai virus (47.6%), M. pulmonis (19.0%), and murine hepatitis virus (JHM : 18.2%, MHV : 31.0%), while the rates were high in rat user lots with Sendai virus (24.4%), B. bronchiseptica (39.3%) M. pulmonis (12.5%), murine coronaviruses (JHM : 19.0%, MHV-2 : 28.0%) and Tyzzer agents (MSK : 19.6%, RT : 17.9%) . These pathogenes with high positivities should be monitored indispensably as a quality control of laboratory mice and rats.

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The method for observing the eye-fundus of rhesus monkeys was devised by the use of Kowa RC-2 Hand-held Fundus Camera. 1. For monochrome photography, Fuji Neopan F (ASA 32) and Fuji Neopan SS (ASA 100) films were used. The best result was obtained under the following conditions : the Strong Power Pack “50W” × 6 for Neopan F and “50 W” × 3 for Neopan SS. 2. For color photography, Fuji Color (ASA 100: Negative, Positive) and Sakura Color (ASA 100: Negative) films were used. The best result were obtained under the following conditions : the Strong Power Pack “50W” × 2 for Fuji Color (ASA 100 Negative), “50W” × 3 for Fuji Color (ASA 100: Positive) and “50W” × 3 for Sakura Color. 3. For f luorescein angiography, 0.3ml/kg of 10 % sodium fluorescein was injected into the vein, and then photographs were taken under the condition of “100W” × 6. For monochrome photography (Kodak Tri-X ASA 400: Negative), a combination of Kodak Wratten Filter 47 (excitor) × K. W. 15 (barrier) brought about the best photographic result. For color photography (Kodak Ektachrome High Speed ASA 160: Positive), the filters (K. W. 32 × K. W. 56, K. W. 47 A × K. W. 12. 15, K. W. 47 × K. W. 12.15 and Fuji Filter BPB 45 × BPB 55) were used and the films were developed by a double sensitivity method to obtain the best photograph.

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A simple monitor was developed for measuring the spontaneous motor activity (SMA) of small laboratory animals. The monitor was designed to measure animal ambulation along a horizontal axis by means of two infrared photo-beams. Using the monitor, male mice 7 to 10 weeks of age at the commencement of this experiment showed high SMA values for the first 15 min and low values for the last 15 min of the experiment.

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[in Japanese]

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