Disinfectants, alcohols and other chemicals were studied for effect against Toxoplasma oocysts. They included Lomasept and Neo Kurehasol, one of orthoes, as useful disinfectants against chicken coccidial oocysts. Two strains of Toxoplasma oocysts isolated from unwanted cats that had spontaneously been infected with the small type of Isospora bigemina were used in this experiment. Sensitization with 1% Neo Kurehasol for 120 minutes, with 1% Lomasept for 10 or 15 minutes, or with 5% Lomasept for 5 minutes inhibited sporulation of unsporulated oocysts completely. No sporulated Toxoplasma oocysts were exterminated by any ordinary disinfectant even after 48-hour sensitization. It was confirmed that sensitization with Neo Kurehasol or peracetic acid for 48 hours, with ethanol for 24 hours, or with methanol for 12 hours was oocysticidal. Oocysts that had been sensitized with Lomasept at a concentration of 1%, 3% or 5% for 3 hours were completely exterminated. An oocysticidal effect was observed after 30-minute sensitization with 10% ammonia water and 1-hour sensitization with ammonium sulfide. It took 4 days for 10% formalin to exterminate Toxoplasma oocysts.

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An in vitro study was carried out on cell-mediated immunity in mice experimentally infected with Toxoplasma gondii to estimate the ability of antigenically stimulated lymphocytes. Lymphocytes were collected from immune and non-immune mouse spleens and incubated in the presence or absence of specific Toxoplasma antigen. When normal macrophages were cultured in the culture supernatant from immune lymphocytes incubated with Toxoplasma lysate antigen and infected with Toxoplasma, the intracellular multiplication of the parasite was inhibited remarkably. On the contrary, there was a progressive increase in infected macrophages cultured in the supernatant from immune lymphocytes incubated without antigen, or in the supernatant from normal lymphocytes incubated with antigen. These results suggest that resistance to and microbicidal activity upon Toxoplasma parasites may have been conferred to macrophages by the culture supernatant from immune lymphocytes reacting with Toxoplasma antigen.

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The visceral organs, lymph nodes, brain, eye and striated musculature from 12 swine suspected of the latent infection depending upon gross lesions of the lymph nodes and liver, and from 45 apparently healthy animals having no gross lesions were examined for presence of toxoplasmas by microscopic observation on smear preparations of the organs as well as mouse inoculation test. Among those with gross lesions, 7 animals showed positive results by both the microscopic observation and the isolation, and the remaining 5 animals were proved to be infected by either the isolation (3 animals) or the microscopic observation (2 animals). In the cases having no gross lesions, 5 animals were found to be infected by the isolation of the organisms. In the swine with gross lesions, the organisms distributed widely in the organs examined, except for the gastro-intestinal tract. In the swine having no gross lesions, the striated musculature, brain, lung, stomach, large intestine and eye were found to be favorite sites of localization of the parasites. Of 51 strains from the swine having no gross lesions, 37 were shown to be capable of killing mice, while 77 of 94 strains from the animals with gross lesions were of low virulence for mice.

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Investigation was carried out on the developmental process of the femoral diaphysis in broiler chickens ranging from 1 to 90 days of age. The diaphysis was formed mainly by apposition of newly formed bone tissue resulting from periosteal osteogenesis around the embryonic bone. Endosteal osteogenesis for the diaphysis, on the other hand, was merely concerned with modification of the inner surface. The bone tissue reached the maturing stage at 55 days of age at the earliest. The feature of maturity was recognized at 70 days of age or later. During the developmental period, especially in the active stage, there were distinct differences in the degree of development and thickness between the anterior and posterior parts of the diaphysis. Based on these findings, discussion was made on several diseases and lesions which are characterized by abnormal periosteal and endosteal osteogeneses.

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Fifty-seven swine embryos (10-235 mm in CRL) were examined for the existence of juxtaglomerular cell granules (JGG) in the mesonephros and metanephros. Bowie's staining method was used to demonstrate JGG. (1) JGG of the mesonephros appeared first in an embryo 12 mm in CRL and showed the heaviest granulation in an embryo 20 mm in CRL. They could not be observed in embryos more than 67 mm in CRL. (2) JGG of the metanephros appeared first in an embryo 62 mm in CRL and persisted even in an embryo 235 mm in CRL. (3) The Indices of juxtaglomerular cell granules (JGI) were determined on the adult kidney and the metanephos in two groups consisting of embryos 62 to 89 mm in CRL and embryos 109 to 235 mm in CRL respectively. They were 10.8, 2.1 and 5.2 on an average, respectively. It was known that the metanephros developed with an increase in the number of glomeruli with JGG.

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Field surveys on coccidial infection in Japanese broilers were performed with 210 fecal samples collected from 24 prefectures in September (as autumn season) and December (as winter season) in 1973. Oocysts were detected from 61% of the samples tested in September. Single and mixed infection with the acervulina type oocysts were found in 59% of the samples tested, or in 96% of the oocyst-positive samples. Those with the tenella type oocysts were detected in 16% or in 26% and those with the maxima type oocysts in 15% or in 25%, respectively. No brunetti type oocysts were detected. Similar results were obtained from a survey conducted in December. Eimeria mitis was isolated from 2 fecal samples. The summarized results of the surveys conducted throughout the four seasons in 1973 were analyzed statistically, together with the results described in the previous report [9]. Oocysts were detected from 67% of the 399 samples tested. Oocyst detection rates were significantly low in groups of young age up to 30 days. Neither seasonal nor regional differences were observed in oocyst detection rate or oocyst type distribution. E. acervulina was a predominant on all Japanese broiler farms and throughout the year of 1973.

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Observation was carried out on 23 domestic cats involved in an outbreak of feline viral rhinotracheitis in a cat-breeding colony. The disease was highly contagious and exclusively characterized by acute signs of the involvement of the upper respiratory tract with marked emaciation. In the virological study, cytopathogenic agents were isolated in feline kidney monolayer culture from nasal and throat swabs of most infected animals. All the isolates exhibited essentially the same cytopathogenic characteristics. Physicochemical and biological studies on one representative isolate revealed that the isolate had many characteristics in common with the Viruses of the herpesvirus group, especially with the causal agent of feline viral rhihotracheitis. Pathological changes were found mainly in the mucous membranes of the upper respiratory tract, conjunctiva and mouth. In these areas, degeneration was found together with formation of intranuclear inclusion bodies in the mucous epithelia. The epithelia often underwent desquamation, which resulted in destruction of the epithelial layer. At the same time, marked inflammatory exudation occurred in the lamina propria mucosae, accompanied by edematous swelling and cellular reaction. Degeneration of the turbinate cartilage and destruction of the turbinate bone were also seen in some cases. Intranuclear inclusion bodies were mostly amphophilic and occupied almost the whole area of the markedly swollen nucleus without any clear halo. Some of them were acidophilic and surrounded by a distinct, wide halo.

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The antineoplasmic agent, cyclocytidine (2, 2'-anhydro-i-β-D-arabinofurano-sylcytosine hydrochloride), was examined for distribution, excretion and metabolism in rhesus monkeys. These monkeys have a high activity of cytidine deaminase in their tissues, as well as human beings. When monkeys were injected intravenously with ³H-cyclocytidine, high concentrations of radioactivity were detectable in the kidney, liver, pancreas and adrenal gland. The cumulative content of ³H in the urine reached approximately 37% of the administered dose for 320 min after the injection. A very small amount of ³H was found in the lumen of the digestive tract. It was suggested that the urinary passage might be a predominant route for the excretion of cyclocytidine. When monkeys received an oral dose of the labeled compound, the concentration of ³H was the highest in the kidney and liver of all the organs tested, as seen in the case of intravenous injection. Orally administered ³H-cyclocytidine underwent a metabolic destruction to ³H-arauridine (1-β-D-arabinofuranosyluracil) through ³H-aracytidine (1-β-D-arabinofuranosylcytosine) and finally to ³H-water in the digestive tract. When monkeys were sacrificed 2, 880 min after oral administration with ³H-cyclocytidine, there was an increase in the relative value of this labeled compound to ³H-aracytidine, ³H-arauridine, and ³H-water accompanied by the transport of the intestinal contents containing the ³H-compounds to the anal portion. The cumulative content of urinary ³H and the residual amount of ³H in the digestive tract were approximately 72 and 15% of the administered dose, respectively, for the same period of exposure. This sufficient recovery of radioactivity may reflect the production of ³H-water from the labeled compound by decomposition.

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The intrinsic innervation of the bovine forestomach was investigated by analyzing the responses of isolated smooth muscle preparations to transmural electrical stimulation. Transmural stimulation (TMS) caused a contraction or a contraction followed by relaxation in longitudinal muscle (LM) strips prepared from the anterior (ras) and dorsal (rds) sacs of the rumen, and from the greater curvature of the reticulum (ret), and the omasum (oma). The excitatory component of the biphasic response elicited by TMS was enhanced by anticholinesterases. After atropine treatment, it was converted into an inhibitory one. The relaxation was predominantly obtained in the LM of rds and the circular muscle (CM) of oma. It was entirely resistant to adrenergic α- and β-blockers or a combination of them and guane-thidine. Tetrodotoxin and cocaine inhibited or abolished reversibly both excitatory and inhibitory responses evoked by TMS, while hexamethonium had little effect on them. Stimulation began to cause the contraction at the frequency of 2-5 Hz and response reached a maximum between 40 and 80 Hz with the supramaximum intensity. This relaxation in response to TMS appeared at 2 Hz and reached a maximum at 10 Hz or less. Adrenaline caused a contraction followed by a relaxation in the LM of rds and a contraction in the CM of oma, but they were inhibited almost completely by phenoxybenzamine and propranolol, Tespectively. These results suggest that the smooth muscle of the bovine forestomach was supplied by postganglionic excitatory cholinergic nerves and nonadrenergic inhibitory nerves.

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