For estimating optimum environmental temperature accepted as comfortable by rats themselves, we measured tail skin temperatures by thermograph and observed behaviors in adult rats at the room temperatures of 20, 22, 24, 26 and 28°C. The five rats grouped in a plastic cage were inclined to be in a tight squeeze at 20, 22 and 24°C whereas they set themselves separately each other at 28°C. At 26°C, the behaviors of the rats were the intermediate of these two types. The tail skin temperatures of these grouped five rats were kept high and the lowest was 28.5°C at the room temperature of 20°C. On the contrary, the tail skin temperature of the single rat in another same type cage was much lower at the room temperatures of 24°C and lower and reaches to 20°C at the room temperature of 20°C, although it was close to those of grouped rats at 26°C and almost equal to those at 28°C. The inside temperatures of the cage containing five rats were higher than the room temperatures but the differences were less than 2°C. At the room temperature of 28°C, both of the single rat and the grouped rats smeared themselves with their saliva to increase heat dissipation. From these results, we considered the ambient temperature range in which a single rat can hold the high tail skin temperature and the salivation is not necessary as the comfortable temperature range for rats.

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This study was intended to demonstrate the neurological characteristics of idiopathic neurologic diseases of dogs and cats as a material for evaluating them as animal models for human diseases. A hundred and nineteen animals selected for this study from among outpatients with various neurological disorders presented to the Veterinary Hospital of University of Tokyo were studied mainly by the neurological examination with assistant methods of electroencephalography and electromyography. Hydrocephalus and vestibular diseases were highest in incidence in dogs, followed in order by encephalitis and epilepsy. Choleiform movements or other abnormal movements such as athetosis and hemiballism that are seen in diseases of the extrapyramidal system of man were not observed in dogs. Cerebellar degenerative disease showed the highest incidence in cats, which is believed to occur by transplacental infection of panleukopenia virus. Intervertebral disk disorders, the most common neurologic disease in the dog, usually occured in the thoracic, unlike in man, and lumbar segments, not only causing pain but precipitating paresis or paralysis of the legs or of the trunk.

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The parotid gland of Chinese hamster was examined by light and electron microscopy. The parotid acinar cells contained acidophile granules and reacted with the periodic acid-Schiff (PAS) reagent but failed to stain with alcian blue (AB) . The acini were composed of light, dark and specific light cells containing secretory granules of various sizes and densities. Intercalated duct cells were composed exclusively of light cells and contained a few vesicles, fine granules and polygonal granules. Striated duct cells were PAS-positive and AB-negative, being composed of light and dark cells. These cells contained vesicles and fine granules, and the light cells in the male contained electron dense polygonal granules. No myoepithelial cells were detected around the acini, intercalated ducts or striated ducts, while nerve terminals were demonstrable among adjacent acinar cells or between the acinar cells and the underlying basement lamina.

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Two of 80 Cynomolgus monkeys, Macaca fascicularis, imported from Indonesia showed weakness, anorexia, paralysis of extremities and dysstasia. The blood test conducted at the time of autopsy proved that the white blood cell count markedly decreased in both cases and the blood urea nitrogen content increased in Case No.1. In Case No.2, a high blood sugar value, a low red blood cell count and a low hematocrit value were recognized. Histologic examinations revealed the presence of fragments of a nematode in the subarachnoid space of the cerebrum, granular layer of the cerebellum and gray matter of the cervical spinal cord. The findings of eosinophilic meningitis, necrosis, foreign body giant cells and cellular infiltration predominantly with eosinophils were also noted there. Morphological features of the nematode found in the tissue sections were identical, in all respects, with those described by predecessors who made morphological observations on the cross sections of Angiostrongylus cantonensis. Immunoelectrophoretic analyses of sera from these monkeys demonstrated the presence of band“a”, which has been described to be highly specific to human A. cantonensis infection. Based on the above-mentioned evidences, the parasite fragments found in the histological sections from the monkeys were identified as A. cantonensis. The cases of natural infection reported herein represent the first, to our knowledge, in which migration of A. cantonensis larvae in the central nervous system of monkey was demonstrated. The present observation suggests applicability of simian angiostrongyliasis as a model for infections in man.

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Comparative histologic observations were made of the sinuatrial nodes of avian hearts from a short-tailed shearwater (Puff inus tenuirostris), a black-crowned night heron (Nycticorax nycticorax), two ducks (Anas platyrhycha domestica), eight Japanease quails (Coturnix coturnix Japonica), a pigeon (Columba livia domestica), a macaw (Ara macao), three budgerigars (Melopsittacus undulatus) and a jungle crow (Corvus macrorhynchos) . The node lies between the right atrial myocardium and epicardium at the right caudal region of the orifice of right anterior vena cava, where the right and left sinuatrial valves come close each other and fuse with the right atrial wall. The sinuatrial node is well developed in the duck, black-crowned night heron and budgerigar and enters into the both sinuatrial valves and, in the budgerigar, further into the sinus septum. In the duck and black-crowned night heron, the node is composed of two types of cells ; the one is atrial muscle-like cells and the other has morphologic characteristics intermediate between atrial muscle fiber and the Purkinje fiber. The node cells of the budgerigar are of the intermediate cells, while the nodal cells in the jungle crow, macaw, short-tailed shearwater, pigeon and Japanese quail are totally atrial muscle-like cells. The nodal cells of these birds are continuous with the adjacent ordinary cardiac muscle fibers and subendocardial Purkinje fibers of the right atrium, but do not reach to the atrioventricular node. There is an extensive network of Purkinje fibers beneath the endocardium and around arteries in both atrial walls, though not as far as to the atrioventricular node, nor to the ventricle.

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The Himalayan rabbit, Chbb: HM has been bred in Kawanishi for about 10 years. The advantage of this strain of rabbit is its mature body-weight of 2.0-2.2kg. In our labs the following parameters of the Himalayan rabbit have been observed: Conception rate 96%, miscarriages 2.7%, viable offspring 6.1±2/litter, weaning rate 77-92% and malformation rate 1.3%.

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Adult male and female rats were inoculated with tween 80-ethylether-formalinultraviolet inactivated Sendai virus (Sv-V) and examined for the production of hemagglutination inhibition (HI) antibody. There were no significant differences in the antibody titers between males and females, and among the various routes of inoculation except for the intranasal which was not effective. The antibody became detectable 7 days after a single inoculation with 10⁵ HAU of Sv-V. The antibody titer, which had its peak 21 days after the inoculation, persisted for 200 days and declined gradually thereafter. The HI antibody titers were correlated with inoculated Sv-V doses and a predominant booster reaction with the vaccine was observed. Maternal antibodies were detected in sucklings born to dams hyperimmunized with the vaccine. The titers were similar to those of the dams until 3 weeks after birth but declined rapidly after weaning at 4-week-old. The titers of fetuses and neonates before suckling were significantly lower than those of the sucklings.

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Over a period of 1973 to 1979, a serologic survey of virus infections was conducted on feline sera collected in four universities which located in different prefectures ; Obihiro, Saitama, Kanagawa and Tokyo. A significant hemagglutina-tion-inhibition (HI) antibody titer of 1 : 8 or higher to feline panleukopenia virus (FPLV) was detected in 130 (58%) of the 226 sera used. No remarkable difference in the HI antibody prevalence in cats to FPLV was recognized by years or localities. Of a total of 188 cats tested, 99 (53%) presented positive serum neutralizing (SN) antibody titers to the No. 1 strain of feline calicivirus (FCV) . Especially in Kanagawa, 17 (77%) of the 22 cats had positive SN titers. However, only 42 (22%) of the 188 sera showed positive SN titers to the Kyoritsu strain of FCV. Such lower positivity in the cats was observed with 13% in the SN test to human reovirus type 3 (Reo-3) . The incidence of positive SN antibodies to feline rhinotracheitis virus (FRV) also remained in low values of 20 to 27% with the exception of high percentage of 86 in Tokyo. The dissemination of FPLV, FRV, FCV and Reo-3 was briefly discussed in relation with the age distribution of viral antibodies in cats.

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An albumin deficient and jaundiced rat (AJR) strain was established from crosses between Albumin-Deficient rats (NAR) and jaundiced Gunn rats. AJRs have a double homozygous mutant trait (alb/alb, j/j), and systemic jaundice and various neurological signs are observed 5-7 days after birth, kernicterus occures and they die within three weeks after birth. This strain of rats may serve as a mdel of human kernicterus and also be useful in elucidating the mechanism of bilirubin metabolism.

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The food intake, nitrogen retention, apparent digestibilities and other factors were compared in adult Wistar strain male germf ree rats given irradiated or autoclaved CL-2 diets. They were no differences between the rats fed the irrad-iated and the autoclaved CL-2 diets.

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Female Sprague-Dawley rats were given 1.25mg testosterone propionate subcutaneously within 24 hours after birth and 30mg 7, 8, 12-trimethylbenz (a) anthracene per 1 kg of body weight intravenously at 50 days of age. In these neonatally androgenized rats, the increase of the anogenital distance, aplasia or hypoplasia of the vagina, persistent estrus on the vaginal smears and eosinophilic substance in mammary glands were observed, with no corpus luteum formation in the ovaries, and the induction of mammary carcinomas by 7, 8, 12-trimethylbenz (a) anthracene was strongly supressed.

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The relationship between the refractive index and specific gravity of urine was studied with specimens from 165 Sprague-Dawley rats, by graphic analysis of the plot of the ref ractometrically determined index against the specific gravity which was measured with a pycnometer. 1. A linear regression was demonstrated between the refractive index and specific gravity. 2. The nomogram fitted the data of even those samples with high refractive index and specific gravity, irrespective of changes in food or water intake and protein or glucose contents in the urine. 3. The nomogram was in good agreement, in respect of linearity, with the regression line derived from the conversion table of TS meter by the American Optical Corporation and also with the nomogram of the Japanese Society of Clinical Pathology. It approximated more closely to the former than to the latter.

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Localization of Pasteurella pneumotropica was investigated in the respiratory tract, conjunctiva and vagina of 5-week-old, 10-week-old and retired asymptomatic mice and rats. The highest isolation rate of the organisms was obtained in the pharyngolarynx, showing 85 to 97.5% in carrier mice and 100% in carrier rats. Numbers of the organisms in this site were 10^3-5 and 10^7-8 organisms/g tissue in 4-week-old mice and rats, respectively. Isolation rates in the nasal cavity and trachea of the both animals were not so high as those in the pharyngolarynx, but usually higher than those in the external nares. The organisms were rarely isolated from the lung. Isolation of the organisms from the conjunctiva was common in rats, especially in young ones, but rare in mice. About 30% of carrier mice and 50 to 100% of carrier rats harbored the organisms in their vaginas.

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The process of CO₂ euthanasia on mouse, rat, guinea pig and rabbit was observed using a CO₂ euthanasia cabinet. The cabinet was filled with CO₂ gas and the caged animal was placed into the cabinet. These animals quietly collapsed and their respiratory movement ceased within 25-225 seconds. A-V block was the first arrhythmia recognized on ECG in all cases. The arrhythmia recorded on ECG included complete A-V block, A-V dissociation, ventricular escape rhythm, atrial fibrillation, ventricular flutter and ventricular fibrillation. It could be concluded that euthanasia was satisfactorily performed on these species by means of the CO₂ euthanasia cabinet.

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