Nine Macaca monkeys were inoculated experimentally with 100, 000 to 400, 000 embryonated eggs of Toxococara canis. Of them, four belonged to Macaca fascicularis, one to M. nemestrina, two to M. cyclopis, and two to M. fuscata. Six infected monkeys, Nos. 1 to 3, 5, 6 and 9, which suffered from a mild invasion of the CNS by larvae of T. canis, showed no clinical abnormality, except mild or moderate inappetence and depression for several weeks together with occasional mild coughing. The remaining three infected monkeys, Nos. 4, 7 and 8, harbored considerable numbers of viable larvae not only in the thoracic and abdominal viscera but also in the CNS, and began to develop such clinical signs as anorexia, weakness and coughing 4 to 7 days after infection. Severe neurological signs that terminated in paralysis were also noted in these three animals on the 8th to 16th days. The postmortem examination of them revealed parasitic granuloma formation and focal tissue destruction with hemorrhage at numerous sites on the cut surfaces of the brain and spinal cord. From these results, it should be emphasized that the severe neurological disorders resulted from the CNS damage which had been caused by the invasion of T. canis larvae in the brain and spinal cord. Hematological findings of the infected animals included transiently reduced erythrocyte counts and marked eosinophilia. The latter appeared soon after inoculation, increased to a high degree between the 2nd and the 4th week, and declined as the infection progressed. Analysis of their blood plasma also showed increased globulin concentrations, reduced albumin values, and decreased albumin/globulin ratio, in addition to elevated plasma transaminase levels. No important changes were found in any other parameter.

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A total of 28 strains of Yersinia pseudotuberculosis were isolated from the cecal contents of 2, 041 apparently healthy swine collected from three abattoirs in Kurayoshi, Hiroshima and Fukuoka, respectively. The rate of isolation and the serotype distribution differed from one abattoir to another. Strains of type III were predominant. All the organisms were isolated in the colder months. It should be emphasized that swine are important reservoirs not only for Y. enterocolitica but also for Y. pseudotuberculosis.

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Clinical and pathological examinations were made on a mongrel dog having progressive and systemic muscle atrophy. Clinically, the progressive atrophy was prominent in the temporal and masseter muscles as well as muscles of four limbs during about a year since the first clinical examination. Hematological examinations made at earlier stages of observations revealed a normal level of the counts of red and white blood cells and hematocrit, while eosinophils ranged from 9 to 10% of leucocytes. Serum transaminase levels were considerably high, and there was a little elevation in β-globulin. At autopsy, the atrophy and paleness were evident in most skeletal muscles, especially in temporal muscles leaving only epimysium with a small amount of connective and adipose tissues. Histopathologically, atrophied muscle fibers exhibited degeneration and necrosis accompanying replacement by increased connective or adipose tissues and infiltration of plasma cells and lymphocytes. Electronmicroscopy of severely affected portions of M. gracilis and M. gastrocnemius revealed vascular changes with edema and swelling of endothelial cells. The diaphragm, tongue and cardiac muscles were also involved having eosinophil infiltration. These findings were discussed in comparison with canine eosinophilic or atrophic myositis.

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The carrier state was developed in 12 of 13 dogs given orally with 39-92 cells of S. typhimurium harbored in the canine feces, while none of 3 dogs with 60 cells of a fresh isolate of the serovar produced shedder state and antibody. In the former, the organisms were excreted in the feces for 18 to 24 days. The organisms settled in the mucosa of middle part of the ileum one day post-administration, and then, spread to the mucosae of lower part of the ileum, caecum, and upper part of the colon 2 or 3 days, giving the highest number in the ileal mucosa. On days 5 to 15, the multiplication of the organisms in the mucosae of those parts became prominent, especially in the parts adjacent to the ostium ileocaecocolicum. The jejunal lymph node became positive for Salmonella from the 2nd day. The antibody was found from the 7th day. None of the dogs showed clinical signs and gross lesions. Thus, it was demonstrated that the carrier state in dogs was the latent infection, and the ileal mucosa in the earlier stage of infection and the mucosae of neighboring parts to the ostium ileocaecocolicum in the later stage served as the major site of localization and multiplication. The infectivity of "the organisms in feces" to produce the carrier state was markedly higher than that of the fresh isolate.

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Guinea pigs and rats infected with the Taiwanese strain of Angiostrongylus cantonensis were monitored for the evolution of delayed hypersensitivity (DH) responses by assessing macrophage migration inhibitory factor (MIF) and delayed-type skin reactivity. These animals were also examined for the production of hemagglutinating (IHA) and precipitating antibodies. In guinea pigs, MIF response was consistently positive throughout 12 to 35 days post-infection. In fact, MIF production was shown by lymphoid cells from the cervical lymph nodes and spleen from infected animals. Delayed-type skin reactivity was correlated with the results of MIF assay. Contrarily, both IHA and precipitating antibodies were not detected in guinea pig sera throughout the course of infection. However, sera from both non-infected and infected guinea pigs yielded an immunologically non-specific precipitin band against A. cantonensis antigen. In rats, MIF response, as measured by the direct method, was variable throughout 6 to 77 days postinfection and the MIF results did not necessarily agree with the dermal reactivity. However, similar assay by the indirect method using normal guinea pig macrophages as indicator cells demonstrated that MIF activity could be detected in the cervical lymph node cells obtained from rats on days 7 and 37, whereas MIF from the mediastinal lymph node cells was first detected on day 29 and most frequently shown at later stages of infection. Precipitating antibody was first detected in sera from an infected rat 6 days postinfection while IHA antibody occurred first on day 34. Histologically, dermal reaction of the infected guinea pigs indicated a pronounced infiltration of mononuclear cells in the dermis. In rats, however, little cellular infiltration was present in the upper or midzone of the dermis, although massive infiltrative lesions were predominant in the subcutaneous fat and muscle and the deeper connectivd tissue. The present results suggest that DH is involved in immune responses of both guinea pigs and rats to A. cantonensis infection.

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In the preventriculus of the domestic goose, there are the V. proventricularis dextra and V. proventriculolienalis, both of which are absent in the duck. The former is not so developed that the venous blood from the right dorsal part of the proventriculus is drained caudally by the well-developed Anastomosis cum v. proventriculari sinistra and empties into the Pars transversa of the R. sinister v. portae via the V. proventricularis sinistra. Although it is difficult to estimate the accurate distribution of venous blood of the avian proventriculus, more than half of the blood from the proventriculus of the goose is collected into the precava after passing through the V. proventricularis cranialis due to the prescnce of the poorly formed V. proventricularis dextra. In the wall of the proventriculus of the goose there is a rather dense venous network formed by anastomoses of V. proventricularis cranialis, V. proventricularis dextra, V. proventricularis sinistra and V. gastroproventricularis which empties into the V. gastrica sinistra. The systemic circulation is connected more closely with the portal circulation by this network in the goose than in duck and chicken. There are no differences between the arterial and venous supplies in the ventriculus (muscular stomach) of the goose. Arterial branches perforate the tissues of this organ in the marginal area and the intermuscular groove like venous tributaries. The proventricularis sinistra, V. gastrica intermuscularis, V. gastrica ventralis and V. gastrica sinistra empty independently into the left hepatic lobe in the goose. Since all of them have the same function in the hepatic portal system, it is proposed to use the V. portae hepatis sinistra as the general term for the four veins.

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Two experiments, I and II, were carried out on guinea pigs to elucidate the defense mechanism against Metastrongylus apri infection. In Experiment I, to produce the status of scarcencss in thymus-derived cells (T-cells) animals were exposed to whole body X-irradiation (300 R) seven days after thymectomy. Immediately after exposure they were vaccinated orally with 1, 000 larvae attenuated by 5×10⁴R of X-rays (Group A). On the 25th day after vaccination they were subjected to challenge infection with 500 normal larvae. Two control groups, B and C, were set up. In Group B, animals were not treated, but vaccinated and challenged. In Group C, animals were not treated nor vaccinated, but challenged. All the guinea pigs were killed on the 21st day after challenge to examine the presence of worms in the lungs. The number of worms recovered from the lungs was 0-77 (mean, 22.8) for Group A, 0-2 (mean, 0.3) for Group B and 1-116 (mean, 43.4) for Group C. There was a significant difference in worm burdens, as determined by Mann-Whitney's "U" test, between Groups A and B, but not between Groups A and C (P&lt0.05). These results showed that T-cells might play an important role in the identification of larval antigen. In Experiment II, thymectomized guinea pigs were vaccinated orally with 1, 000 larvae attenuated by 5×10⁴R of X-rays. Then 25 days later they were subjected to challenge infection with 500 normal larvae. They were given intraperitoneally with 1.0 ml of antithymocyte serum (ATS) on the day of challenge infection and then with 0.5ml every two days until 9 injections were made (totalling 5.5ml each), so that T-cells might be suppressed (Group A). Two control Groups, B and C, were set up. In Group B, animals were not treated, but vaccinated and challenged. In Group C, animals were not treated nor vaccinated, but challenged. On the 21st day after challenge, all the animals were killed to examine the presence of worms in the lungs. The number of worms recovered from the lungs was 4-254 (mean, 44.7), 0-5 (mean, 1.2) and 29-274 (mean, 95.8) for Groups A, B and C, respectively. There was a significant difference in worm burdens, as determined by Wilcoxon's "U" test, between Groups A and B, as well as between Groups A and C (P&lt0.05). These results showed that T-cells, which had a close relationship to cell-mediated immunity, might be suppressed by thymectomy and ATS injection, suggesting the important role of these cells in the defense mechanism against M. apri infection.

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Subcellular distribution of ^&lt109&gtCd and ^&lt109&gtCd incorporation into cadmium-binding protein (Cd-BP) were investigated in respective tissues of Cd-pretreated and intact control male rats and Japanese quail injected intravenously ^&lt109&gtCd-cadmium chloride. The liver contained the highest level of ^&lt109&gtCd of all the organs in the animals and birds examined. The largest amount of ^&lt109&gtCd was determined in the soluble cytoplasmic fraction derived from the homogenates of the liver, kidney and pancreas of control rats, as well as from those of the liver, kidney, pancreas and proventriculus of control quail. The crude nuclear fraction of the gastric gland of the control rats took up nearly half the amount of ^&lt109&gtCd contained in the homogenate of this gland of the control rats. Cd-exposure had in no case any significant effect either on the ^&lt109&gtCd uptake by the whole tissue or on the compartmentalization of ^&lt109&gtCd in the soluble fraction of any tissues in the rats and quail. In rats, as well as in quail the Sephadex gel filtration of the soluble fraction of each tissue gave rise to two peaks of ^&lt109&gtCd in the elution profile. The first peak was a minor one shown at the exclusion limit of Sephadex G-75 and the second peak a major one having an elution factor of approximately 2.0. The second peak of ^&lt109&gtCd was associated with a slight absorbance of ultraviolet (260nm) in the liver, but not in any other organ, of control rats and quail. Cd-exposure intensified both ^&lt109&gtCd peak and absorbance of ultraviolet. The second component of ^&lt109&gtCd was considered to be Cd-BP from its elution profile on Sephadex G-75. The Cd-BP-like component may be synthesized not only in the liver and kidney but also in the pancreas and gastric gland, regardless of the species of animal. Some possible mechanisms were discussed when Cd-BP had failed to prevent the initiation of Cd-toxicity.

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A total of 298 strains of Staphylococcus aureus isolated from chicken staphylococcosis of different types were subjected to 26 phages of the International Series. One hundred and ninety-one (64.1%) strains were typable by one or more of the phages at 1, 000 RTD, but only nine of them were lysed at RTD. Of these typable strains, 129 (67.5%) belonged to type III, 40 (20.9%) to mixed types, 17 (8.9%) to type II and 5 (2.6%) to type IV. Frequent lysis were obtained with phages 75, 53, 54, 7, 6, 77 and 3C, and 95.8% of the typable strains were lysed by any one of these phages. There was no significant relationship between staphylococcal phage types and types of disease. Type III strains were commonly found in staphylococci isolated from many chicken farms regardless of districts, and thus, they were considered to be distributed widely among chickens in this country. On the other hand, type II or IV strains were obtained from a very limited number of farms.

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The chloride content of buffalo cervical mucus reached a maximum level of 632.4 mg/100 ml at the time of oestrus. A test was developed for the detection of oestrus in buffaloes. It was based upon changes in the chloride content of cervical mucus. Since it was simple and rapid, it could be done by attendants in the field. It was recommended as a routine test on a farm where silent heat was predominant among buffalo cows.

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Histochemical changes in the amount of glycogen and lipids in the endometrium were observed during the course of estrous cycle and pregnancy of goats, crossbred of Saanen and native kind of Okinawa. The results obtained were as follows: 1) In the layer of surface epithelium, a small amount of glycogen and lipids were detected during non-breeding season, while these substances showed a tendency to increase during pregnancy, 2) Glycogen was not present in the glandular epitheliura during non-breeding season and estrus, but it tended to increase from the diestrus to the pregnancy. Lipids in the glandular epithelium also increased from diestrus to the pregnancy, and 3) Glycogen-containing cells and pigment cells showing PAS-positive reaction were found in the endometrial stroma. Numerous glycogen-containing cells were found during a certain stage of diestrus and in the all stages of pregnancy. On the other hand, pigment cells were variably observed during the sexual cycle, but were disappeared at the pregnant stage.

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