This report dealt with the change of body temperature (rectal temperature) in the newborn cynomolgus monkeys (Macaca fascicularis) with a view to take it as an index for their health conditions. The body temperatures of 183 newborn babies which were well cared for by their mothers was 33.0 to 37.7°C about 10 hr after birth. On the other hand, the body temperatures of 21 newborn babies which were not well cared for by their mothers was very low, ranging from 24.1 to 34.8°C. In five newborn monkeys which were well cared for, the body temperature averaged about 36°C just after birth and then declined rapidly by 32 to 33°C at 40 to 50 minutes after birth. Then it gradually began to rise, reaching 36 to 37°C at 180 to 240 min after birth. In the other four newborn monkeys which were delivered by Caesarian section, the temperature was 37 to 38°C just after birth. Then it decreased to 29 to 32°C at 120 minutes after birth when the newborns remained singly in a cage without warming.

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The skin of the pika (Ochotona rufescens rufescens) was found to be remarkably sensitive to the primary irritation of sodium hydroxide, as compared with the skin of the rabbit. After exposure to 0.1 N sodium hydroxide for 24 hr, the pika skin showed severe erosion, ulceration and necrosis as well as crust formation and hyperkeratosis with vascular dilation, and cell infiltration. The changes appeared already within 1 hr after 1 N or 3 hr after 0.1 N sodium hydroxide application. After application of acetic acid, changes were apparent while less remarkable.

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Eight commonly used chemical disinfectants and physical treatments (UV irradiation and heating) were applied to both enveloped RNA viruses (Sendai virus, canine distemper virus) and unenveloped RNA viruses (Theiler's murine encephalomyelitis virus, reo virus type 3) to inactivate infectious virus particles. According to the results, alcohols (70% ethanol, 50% isopropanol), formaldehyde (2% formalin), halogen compounds (52ppm iodophor, 100ppm sodium hypochlorite), quaternary ammonium chloride (0.05% benzalkonium chloride) and 1% saponated cresol showed virucidal effects giving more than 99.95% reduction in the infectivity of virus samples of Sendai virus and canine distemper after 10 minutes exposure. There was no significant difference in the effects on the two enveloped RNA viruses. The susceptibility of unenveloped RNA viruses to chemical disinfectants and physical treatments differed greatly from the enveloped viruses. The two unenveloped viruses showed distinct resistance to 50% isopropanol, 2% formalin, 1% saponated cresol and to physical treatments (heating at 45, 56, 60°C., and UV irradiation) . These results indicate that using physicochemical methods to inactivate RNA viruses in laboratory animal facilities should be considered in accordance with the characteristics of the target virus. For practical purposes in disinfecting enveloped RNA viruses, 70% ethanol, 0.05% quaternary ammonium chloride and 1% saponated cresol diluted in hot water (>60°C) are considered as effective as UV irradiation. For unenveloped RNA viruses, halogen compounds, more than 1, 000 ppm sodium hypochlorite or 260 ppm iodophor are recommended over a period of 10 minutes for disinfecting particles, although these compounds result in an oxidation problem with many metals.

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Serum and pituitary prolactin (PRL) concentrations were measured during the estrous cycle of the rat with particular attention to the afternoons of the days of proestrus and estrus. Homogenizing machines, a Polytron and Sonifier, were used to extract PRL from the pituitary gland. The effects of ether anesthesia and restraint were also examined on the afternoons of both proestrus and estrus. The occurrence of a surge in PRL secretion during proestrus was confirmed with a peak at 1500 h, and this was accompanied by a decline in pituitary PRL content. A relatively high level of serum PRL was observed in the afternoon of estrus, during which time pituitary PRL content increased progressively. Ether anesthesia had no effect on the proestrous PRL surge, while restraint enhanced it. On the afternoon of estrus, restraint completely suppressed the rise in serum PRL, but ether anesthesia failed to suppress it completely. From these results, the following conclusions were drawn: 1) the PRL surge on the afternoon of proestrus occurs without synthesis of the hormone in the pituitary; 2) PRL secretion on the afternoon of estrus is accompanied by its synthesis in the gland; 3) the PRL response is distinct for each type of stress applied; and 4) PRL secretion is thus regulated by different mechanisms in proestrus and estrus.

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Morphological changes of pancreatic B cells were investigated in ventromedial hypothalamic (VMH) -lesioned obese rats. An increase in body weight, a decrease in body length, and a marked increase in fat-pad were observed in VMH-lesioned obese rats. The volume density of pancreatic islets and that of B cells in VMH-lesioned obese rats were more increased than those in sham-operated control rats. The B cells of VMH-lesioned obese rats often showed a slight reaction for aldehyde fuchsin or anti-pig insulin serum. By the electron microscopy, the degranulated B cells were found to contain well developed Golgi apparatus and rough endoplasmic reticulum. These obsevations indicate increased activities of synthesis and release of insulin. We concluded that VMH-lesioned obesity was caused by accelerated lipogenesis with hypersecretion of insulin.

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Electrophoresis of tear proteins on agarose gel showed polymorphism in the fastest migrating protein among 32 inbred strains of rats. In 8 strains, the protein was missing (RTP-2B), while the other strains expressed the protein (RTP-2 A) . The trait was found to be controlled by a single autosomal locus. The designation Rtp-2 locus, with two alleles (Rtp-2^a, Rtp-2^b), is tentatively proposed. The Rtp-2 locus is loosely linked to c locus, with a recombination frequency of 36.7±5.4 percent.

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The distribution of an RFLP in EcoRI fragments of the cardiac myosin heavy chain gene among 29 strains of laboratory rats was examined. Southern blot hybridization of rat genomic DN As with rat cardiac myosin heavy chain cDNA as a probe demonstrated an interstrain variation in one of eight EcoRI fragments. Of the 28 inbred strains examined, 10 had a fragment of 10 kbp, whereas 18 had a fragment of 7.5 kbp. The 15 samples of the remaining strain (Iar: WI outbred stock) had fragments of either 7.5 kbp or 10 and 7.5 kbp, indicating that this strain has maintained heterogeneity of these fragments.

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Genetic studies demonstrated three loci cotrolling coat colors in the Mongolian gerbil. F₁ hybrids of white gerbils with red eyes and agouti gerbils with wild coat color had the agouti coat color. The segregating ratio of agouti and white in the F₂ generation was 3 : 1. In the backcross (BC) generation (white×F₁), the ratio of the agouti and white coat colors was 1 : 1. Next, inheritance of the agouti coat color was investigated. Matings between agouti and non-agouti (black) gerbils produced only agouti gerbils. In the F₂ generation, the ratio of agouti to non-agouti (black) was 3 : 1. There was no distortion in the sex ratios within each coat color in the F₁, F₂ and BC generations This indicated that the white coat color of gerbils is governed by an autosomal recessive gene which should be named the c allele of the c (albino) locus controlling pigmentation, and the agouti coat color is controlled by an autosomal dominant gene which might be named the A allele of the A (agouti) locus controlling pigmentation patterns in the hair. The occurrence of the black gerbil demonstrated clearly the existence of the b (brown) locus, and it clearly indicated that the coat colors of gerbils can basically be explained by a, b, and c loci as in mice and rats.

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Pathological examination performed on a male 70-day-old Sprague-Dawley rat revealed formation of a large cyst in the hypophysis. The cyst, which completely occupied the adenohypophyseal area, was lined by the epithelial cells. Small masses of the adenohypophyseal cells were occasionally seen to sprout from the cyst wall epithelium.

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Extractable nuclear antigens (ENA) were prepared from liver of C 57 BL/6J mouse and analyzed by SDS PAGE Western-immunoblotting techniques. Some protein components of the ENA, with molecular weights of 94 K, 65 K, 32 K, and 26 K, reacted with antinuclear antibodies in the sera of NOD mice. Incidence of antinuclear antibodies in the sera of NOD mice with aging were measured by ELISA method using the ENA as antigen. The antinuclear antibodies were not detected in young NOD mice (10 weeks old) . However, the incidence increased with aging and reached 100% in the female NOD mice of 40 weeks. In the male NOD mice, the incidence of antinuclear antibodies was delayed and low in comparison with that in female.

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ICGN is a strain of spontaneous nephrotic mice with nonproliferative glomerular lesions. It was derived from an outbred Yok : ICR colony in our laboratory. The renal disease constantly occurred in animals of the first to the tenth generations (>13.0%; 70 days of age) . When affected males were mated with unaffected females, the incidence of the disease in their offspring was 38.8% (n=49) at 70 days after birth. When both parents were affected, their offspring were all affected (n=12) . The disease evenly progressed in both sexes. It usually began 40 to 150 days after birth and death occurred within two months after onset. The animals usually showed sufficient reproductive ability as long as unaffected females were used for mating.

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Concentrations of lactose in milk of Microtus montebelli were measured with the method using with the methylamine reaction. In this method, a small amount of sample (0.5 g) was sufficient for assay, and reproducibility and sensitivity were excellent. This method was very useful for measuring of lactose concentrations in experimental small animals. The average lactose concentration in milk of Microtus montebelli was 1.57g/100g, considerably low in comparison with the value of ICR mice (2.70g/100g) . The low concentration of lactose in milk was considered to be one of metabolic characteristics of Microtus montebelli as a herbivorous animal.

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The D variant of encephalomyocarditis virus (10¹-10⁵ PFU/head) was intraperitoneally inoculated into 4 species of small rodents, rats, mice, Syrian hamsters, and Mongolian gerbils, and the susceptibillity of these animals to EMC virus was examined virologically and histopathologically 3 days after infection. Viral replication was detected in the brain (mice), in the heart (mice and gerbils), and in the pancreas (mice, hamsters, and gerbils) . No viral replication was detected in rats. Histopathological changes were seen in the brain (mice and hamsters), in the heart (mice and gerbils), and in the pancreas (mice, hamsters, and gerbils) . No histopathological changes were seen in rats. The present results suggest that it may be quite passible to produce EMC virus-induced diabetes mellitus not only in mice but also in hamsters and gerbils.

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