Mouse is in use as a laboratory animal for the safety test of anthrax vaccine No. 2. The results obtained in mice were frequently irregular as many experiments in spite of using a definite experimental method. The safety test, however, is closely associated with the security and the immunizability of the vaccine, so that constant result must be required. For that, a committee was formed among the persons concerned with the investigation of anthrax in Japan. The authors, as members of the committee, began to study on the part of mouse as a laboratory animal.
Three strains of mice, C3H, CF#1, and ddD, were subcutaneously and intravenously inoculated with Bacillus anthracis No. 2, strains 34F2 and H13. C3H was not susceptible and the LD₅₀ was 100 times as much as those of the other two. CF#1 was susceptible and the results were rather stable in mortality rate and survival times (Fig. 1 and 2) . Consequently, the strain CF#1 may be efficient for the safety test of vaccine No. 2.
The typical symptom of mice subcutaneously inoculated with the organisms is a hypodermal oedema formation. Then, it was presumed that a different attitude of oedema formation could be observed between C3H and CF#1. From the results of an experiment (Table 5), the hypodermal oedema formation was more difficult in C3H than in CF1. It was appeared that the difference of oedema formation between C3H and CF#1 is parallel to that of the susceptibility of both strains.
It is well known that a substance killing the organisms, anthracocidin, exists in human and rabbit sera and not in murine serum. Since the strain C3H was not susceptible, it was also presumed that an anthracocidin-like substance may exist in the serum of C3H. However, there was no evidence that the substance exists in the serum and in the saline extract of liver and spleen of C3H (Fig. 4) .

View full abstract

Erythrocyte count, leukocyte count, hemoglobin content, serum protein percentage, leukocyte diagnosis were determined in the blood of adult male of 4 different inbred strains mice, dd, rr, ss, and C57BL.
After the means and standard errors for each determination were given for each strain. Statistical significance was tested among the 4 strains.
There were significant genetic differences among the strains in factors affecting erythrocyte number, leukocyte number and hemoglobin content. On the other hand, protein percentage failed to show appreciable variability among the strains. The leukocyte diagnosis, concerning with neutrophile, varied significantly between rr and C57BL.
Erythrocyte number was 1055±64 in dd, 1090±66 in rr, 994±80 in ss and 1117±78 in C57BL (ten thousand) . Leukocyte number was 8, 560±1, 628 in dd, 8, 013±1, 655 in rr, 6, 725±1, 696 in ss and 5, 046±2, 242 in C57BL.
Hemoglobin content was 15.29±1.01 in dd, 16.74±0.68 in rr, 15.53±1.20 in ss and 15.51±1.15 in C57BL (g/dl) .

View full abstract

In general, the hematological examination of the mouse has been performed with the blood taken from the tail (by tail-cut method) and very little is known about the blood from the eye (by eye puncture method) . Studies were made using ddD strain mice in various ages whether the eye puncture method is available for hematological examination comparably with the tail-cut method.
1) As a technique, the eye puncture appeared to be more preferable than tail-cut method because of its advantages in getting a sufficient quantity of blood for the examination easily, consistently and quickly.
2) The analysis of variance demonstrated the significant differences with the erythrocyte and leucocyte counts between the bloods taken from the eye and tail of the mouse, on the other hand no difference was noted in regard to the percentage, of polychromatic erythrocyte or to the differential leucocyte counts.
The variation observed in the erythrocyte and leucocyte counts seemed to be less with eye puncture than regular tail-cut.
3) The age difference in the cell counts of the blood taken either from eye or from tail was found to be significant by the analysis of variance.

View full abstract

Two coat colour mutants of rats (Rattus norvegicus) were caught in the suburbs of Mishima. One of them, a female rat, was characterized by an yellow coat and pink eye, and the other mutant male was characterized by gray coat, ruby eye.
From the genetic analysis of two mutants, it was found that the former has gene p and the latter has gene p^m which is an allelomorph to gene p in wild caught rat.
By successive inbreeding of rats with new mutant charactors, several bred in strains, such as NIG-II, NIG-III and NIG-IV ......are being established in authors' laboratory.

View full abstract

Using blowfly as the experimental animal, DETHIER made the research about the relationship between olfactory response of blowfly and chemical constitution.
The authors intended to make the same line of investigation using Drosophila as an experimental animal. The reason for the choice of the Drosophila exists in the easiness to obtain a genetically pure strain which accordingly brings the advantages in the biochemical and the genetical analysis of the olfactory responses.
During the experiments, the authors had to encounter many troubled, such as finding suitable containers, developing ticks and mold in incubation bottle, selection of male from female, and an unsatisfactory reproducibility in the results.
The only thing which the authors could establish was anesthetic method of Drosophila. To take out the certain number of fly from its incubation bottle, it is recommended to use the technique of so-called “cold anesthesia” instead of commonly used ether anesthesia.

View full abstract