This experiment consisted of three parts; the first was to find out a relation between the sensitizing dose and the challenge dose; the next was to investigate the strain differences in mortality of anaphylactic shock and to find out the strains which are more sensitive to anaphylactic shock ; and the last was to investigate the effect of genetic heterozygosity on the morta lity rate of the shock.
Experiment I : ICR-JCL male mice were sensitized by two subcutaneous injections with 0.08, 0.4, 2.0 or 10mg of egg albumin at five and six weeks of age. Mice of each group were challenged with subcutaneous injections of 0.4, 1.0, 2.0 or 10mg of egg albumin at seven weeks of age. The mortality and the survival time after the challenge injection are shown in Table 1 and Fig.1. There was no difference in both mortality and survival time with the four different sensitizing doses (0.08-10mg of egg albumin) .
It was found that the mortality and survival times following anaphylactic shock were influenced only by the challenge doses.
Experiment II: The mice of eight strains (ICR-JCL, CF#1-JCL, ddN-JCL, C3H/HeN, BALB/c, DBA/2, NC and KK) were sensitized with 2mg of egg albumin by the same route and at the same age as in Exp. I. These mice were challenged by subcutaneous injection with 0.08 to 80mg of egg albumin.
The mortality of the mice from closed colonies (ICR-JCL, CF#1-JCL and ddN-JCL) was generally high, but in inbred stains (except the NC strain), mortality was very low. In the NC strain especially the female, mortality was a maximum (100%) after challenging with 2mg egg albumin, as shown in Tables 2 and 3.
In the NC and BALB/c strains, there was some sex difference in respect to mortality.
Experiment III : Three kinds of hybrids (BALB/c_??_×NC _??_, C3H/HeN_??_×BALB/c _??_ and BA LB/c_??_×DBA/2 _??_) were sensitized and challenged by the same route and at the same age in Exp. II. The mortality of the BALB/c and NC hybrids was half of the mortality in the parent strains. On the other hand, the mortality of the C3H/HeNf×BALB/c and BALB/c×DBA/2 hybrids was as low as in the parent strains. Genetic heterozygosity had no effect on the mortality of anaphylactic shock.

View full abstract

Many reseachers have investigated anaphylactic shock in mice, but there has been no study concerning the effect of the environmental temperature on anaphylactic shock.
In order to investigate the effect of the environmental temperature on the mortality of anaphylactic shock in mice, five strains (ICR-JCL, CF#1-JCL ddN-JCL, C3H/HeN and BALB/c) of mice were used.
The mice were sensitized by subcutaneous injections with 0.08-10mg of egg albumin at five and six weeks of age. These mice were challenged by a subcutaneous injection with 2 mg of egg albumin in a 0.1ml saline solution at seven weeks of age, and thereafter, the mice were divided into three groups and exposed to three different environmental temperatures 10±2°C, 22±1°C or 31±2°C, respectively.
The mortality rate during 70 minutes after challenging is shown in Table 1 and Fig. 1. There was no relation between the sensitized dose and the mortality at each environmental temperature.
The mortalities in each strain increased as the environmental temperature became higher, especially in the C3H/HeN strain, where the mortality at 31°C was 58%, but at 10°C was 0%.
The survival time in ICR-JCL mice after challenging is shown Fig. 2.
The survival time was longer at the lower environmental temperature.

View full abstract

During reared in a plastic isolator, germfree pigs were exposed to micrococci, bacteroides, yeasts and Streptococcus faecalis isolated from feces of a conventional piglet. Experiments were successively carried out to observe the alternation in formation of intestinal flora when the gnotobiotic pigs were exposed to two conventional environments; at first they were placed in a cage set at a clean laboratory (conventional A), and later at an open piggery with conventional pigs (conventional B) . The pigs were fed a sterilized artificial milk through the experimental periods. The results obtained were as follows (Table 1) .
1. Four bacterial species administered orally with each 10⁴ organisms to the germfree pigs at intervals of two days between 20 to 26 days of age. The bacterial counts per gram of the feces at 28 days of age were as follows: Streptococcus faecalis, 10⁹; bacteroides, 10⁸; micrococci, 10^7.5 and yeasts, 10^7.5.
2. The gnotobiotic pigs which were contaminated with the four bacterial species were exposed to conventional A (Photo 1) for five days (from 29 to 33 days of age) . Two days after the exposure, Escherchia coli appeared, reaching rapidly a population of 10^9.5 cells per gram of the feces. Since then, no remarkable changes were observed in the bacterial counts in the feces of Escherichia coli, as well as Streptococcus faecalis and bacteroides. On the contrary, micrococci and yeasts decreased in number gradually and their counts were 10⁴ and 10⁶ per gram of the feces at 33 days of age respectively.
3. The pigs were then transferred to conventional B (Photo 2), and were reared for additional 10 days (from 34 to 43 days of age) . The appearance of 10⁹ organisms of lactobacilli per gram of the feces at 35 days of age was observed after the pigs had been exposed to this environment. Since then the feces per gram were constantly occupied by 10⁹ lactobacilli. On the other hand, micrococci, staphylococci and yeasts were very few or altogether absent in bacterial counts in the feces.
It is therefore considered that enterococci, enteric bacteria and bacteroides of human origin may be easily harbored in multicontaminated gnotobiotic piglets, while lactobacilli of the same origin may hardly be resident.

View full abstract

Fecal flora was examined in six groups of ICR mice which were reared in bacteriologically different environments. As shown in Table 1, gnotobiotic mice (Groups I & II) harbored only enteric bacteria, streptococci, staphylococci and lactobacilli. Bacteroides and yeasts appeared in two groups of SPF mice (Groups III & IV) which were derived from the mice of Group I. SPF mice of Group V, which were kept in an SPF room for four years, and conventional mice (Group VI), which were derived from the mice of Group V, harbored enteric bacteria, streptococci, staphylococci, lactobacilli, bacteroides, yeasts, aerobic spore formers, clostridia and pseudomonads.
Subsequently, the organisms grown on DHL, SF, mannitol-salt and LBS agar plates were divided into several genera, species or biotypes (Table 2) . The organisms on DHL agar plates from gnotobiotic mice showed homologous properties and were classified in genus Proteus. On the other hand, the organisms consisting of Proteus and Klebsiella were isolated from SPF mice of Groups III and IV. SPF mice of Group V harbored Citrobacter, Escherichia and Klebsiella, while conventional mice harbored Escherichia including hydrogen-sulphide producing E. coli, Proteus and Citrobacter. As can be seen from Table 2, the same results as above were observed using SF, mannitol-salt and LBS agar plates, i. e, the number of species or types harbored increased when the gnotobiotic mice were transferred from isolator to SPF room or the SPF mice from SPF room to conventional room.

View full abstract

The fertility in female Gunn's rats was found to be markedly reduced, so the experiments were carried out to make sure of the inheritance pattern of the trait and to establish the best mating system for maintenance or propagation of jaundiced rats by crossing Gunn's rats with Wistar-Imamichi rats.
It was confirmed that the jaundice trait is governed by a single autosomal recessive gene (j) . Among three types of mating, j/j_??_×j/j _??_, j/+_??_×j/j _??_and j/+_??_×j/+ _??_, j/j_??_× j/j _??_ a giving 100% incidence of jaundice resulted in a very low fertility and a very small litter size, while in the offsprings from j/+_??_×j/+ _??_ the incidence of jaundice was much reduced and j/+ could not be distinguished from +/+. On the other hand, in j/+ _??_×j/j _??_ the fertility, litter size and the incidence of jaundice were to be satisfied.

View full abstract