Canine oral papilloma virus (COPV) has been known to possess strict host and tissue specificities. The present study was undertaken to ascertain the oncogenic potential of COPV in a variety of tissues and organs of dogs. Inoculation with a phosphate butfered saline suspension of experimentally produced oral papillomas into the conjunctival epithelium of the eyeball induced tumors at the site of inoculation in 8 of 17 dogs. These tumors began to develop after an incubation period from 45 to 60 days, and attained maximum growth in 2 weeks. The general histological characteristics of the eye tumor were similar to those of oral papilloma. The lesions recovered spontaneously. With the filtrate of eye tumor emulsion, oral papillomas were induced in the oral mucosa of young dogs. Papillomatous tumors were also induced experimentally in the eyelid and skin. When administered with chemical carcinogen (MNNG), papilloma-bearing dogs showed a prolonged course of papilloma. Discussion was made on the progress of virus-induced papillomas. In the course of the present experiment, a 5-year-old male mongrel dog was found to have spontaneous multiple growth of papillomatous tumors in the mucous membrane of the lips and right eyelid. Histologically, the tumors in these organs were papillomas and contained papilloma virus-like particles.

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T-mycoplasmas (Ureaplasma sp.) were isolated from 15 out of 22 pneumonic lungs of calves. Nine of 21 tracheas of the same calves also harbored the same organisms. Mycoplasma bovirhinis was usually isolated simultaneously from the same specimens in smaller numbers. The majority of these calves had been reared on a farm where sporadic enzootic calf pneumonia had been prevalent for years. Forty-three calves and beef cattle without pneumonia harbored no detectable number of T-mycoplasmas in the lung or trachea. Metabolism-inhibiting antibodies to both types of mycoplasmas were detected in sera from dead and affected calves, but not in sera from apparently healthy calves. High titers of antibodies to both bovine viral diarrhea virus and bovine adenovirus type 7 were proved similarly in affected and healthy calves. T-mycoplasmas were considered to play an important role in the occurrence of the lethal type of calf pneumonia.

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Chlorpromazine and phenobarbital were studied experimentally for influences upon the running performance of race horses. Three Thoroughbred horses were used for each drug. Chlorpromazine hydrochloride was injected subcutaneously at a single dose of 0.25, 0.5 or 1.0 mg/kg, and phenobarbital sodium at a single doses of 1 or 3 g per head. An exercise started about 1 hour after the injection. The experimental procedure used was the same as mentioned in the previous report. Chlorpromazine showed a pronounced performance-decreasing effect. In an extreme case, a horse administered with a dose of 1.0 mg/kg could not promptly change the pace from trotting to cantering, but continued to run at canter. Some of the horses administered with chlorpromazine ran with the penis protruded. On the contrary, phenobarbital did not affect the running performance so seriously. Chlorpromazine increased the heart rate during the exercise, particularly at trot and canter, and phenobarbital decreased it at walk and trot. Both drugs decreased the respiratory rate immediately after the exercise. The results obtained suggest that doping with chlorpromazine, even at a relatively small dose, may cause an irreversible locomotor disorder when the doped horse is driven forcedly.

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Young adult forms of Dirofilaria immitis were found in the brains of 2 dogs (Nos. 1 and 2) which died after manifesting such neurological symptoms as depression, dullness and ataxia, and in the right dorsal cerebral vein of a dog (No. 3) which had shown no clinical signs. Pathological and parasitological studies were made on these cases. The results obtained are summarized as follows. 1) Macroscopically, a worm was found in the crus cerebri of Dog 1 and another in the medulla of the gyrus ectosylvius of the left cerebral hemisphere of Dog 2. Neuropathological findings consisted primarily of traumatic destruction and multiple hemorrhagic malacia caused directly by the worm, and secondarily of degeneration of nerve fibers as swelling or disappearance of axis cylinders and myelin sheaths. In Dog 3, a worm was found in the right dorsal cerebral vein, and a malacic lesion with hemosiderosis in the left piriform lobe. There may probably be a relationship between the worm and the malacic lesion. 2) Parasitological examination revealed that all the worms obtained from the brains were young adult forms of Dirofilaria immitis (Leidy, 1856). The worm collected from Dog 1 was female and those from the others were male. 3) For the present disease is distinguishable from ordinary dirofilariasis, the new name Cerebral dirofilariasis was proposed.

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1. The bilateral parotid ducts were ligated in five goats to study the influence of parotid salivation on phosphorus, sodium and potassium homeostasis and acid-base balance. The compositions of urine, feces, blood and rumen fluid were determined during the control period and for four weeks after ligation. 2. The parotid duct ligation caused an increase in urinary phosphorus excretion and plasma inorganic phosphorus level. Fecal phosphorus output decreased, but total phosphorus output in urine and feces changed little. It seems likely that the increase in plasma and urinary phosphorus level and the decrease in fecal phosphorus output may have been caused by the decrease in phosphorus recycling via parotid salivation. Urine pH became acidic and urinary titratable acid excretion increased after ligation. 3. Urinary sodium and chloride excretion decreased transiently by ligation and then returned to the initial level. Urinary potassium excretion did not change after ligation, except for a few days. Fecal sodium and potassium output was not affected. 4. Sodium and inorganic phosphorus levels of rumen fluid decreased rapidly by ligation and then tended to return. to the initial levels. Duct ligation caused a small increase in potassium level and little change in pH of rumen fluid. 5. Plasma bicarbonate, sodium, potassium and chloride levels and blood pH scarcely changed. 6. In ruminants, phosphorus homeostasis seemed to have a close correlation to the parotid function, since a decrease in parotid salivation caused a change in phosphorus homeostasis. It was assumed, however, that sodium and potassium homeostasis might not be influenced so much by the ligation of the parotid duct.

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The maximum, minimum and optimum growth temperatures of 50 psychrotrophic Pseudomonas strains (20 from raw milk, 10 from fresh pork and 20 from frozen veal) and 3 strains of mesophilic bacteria (Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli) were examined by stationary cultivation at 12 different temperatures at intervals of about 5°C between -8°C and 40°C, and by shaking temperature gradient Cultivation at 30 different temperatures at intervals of about 1.5°C between 0°C and 45°C. The growth rates at various incubation temperatures were measured by optical density in trypticase soy broth (BBL) culture, using an electric photometer with 530 nm filter. Of the 50 Pseudomonas strains examined, 42 grew at -8°C after 7- to 15-week incubation in a non-freezing broth (trypticase soy broth with 5% glycerin added), and 47 strains at -5°C after 3- to 4-week incubation. 0f 3 strains unable to grow at -5°C for 10 weeks, one grew at -2°C for 3 weeks, and two at 1.5°C for 4 to 7 days. The maximum growth temperatures of the 50 strains examined ranged from 30 to 40.5°C, or mostly from 33 to 37°C. The optimum growth temperatures of the 50 strains ranged from 25.5 to 34.5°C, but those of 37 strains of them were 30°C or below. It is preferable that all the 50 Psepdomonas strains are called "psychrotrophs" rather than "psychrophiles", according to the following results. Although two of the 50 strains were unable to grow at 0°C within 2 weeks, all the 50 strains grew at temperatures lower than 1.5°C within a week, and their optimum growth temperatures were between 25.5 and 34.5°C. On the other hand, the lowest growth temperatures of the 3 mesophilic strains tested were between 4.5 and 7.5°C by gradient cultivation. These strains showed no growth at 5°C for 14 days by stationary cultivation. Their highest growth temperatures were over 45°C. Their optimum growth temperatures were 37.5 and 40.5°C.

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Changes induced in primary dog kidney cell cultures by reovirus infection were investigated sequentially by virus and antigen estimations, conventional staining and direct fluorescent antibody techniques. Specific fluorescence was first detected 8-10 hours after infection and extended finally all over the cytoplasm. Fluorescence and cytoplasmic inclusion bodies were found to appear in five sequential stages distinguished by shape and location in the cell. These stages were in parallel to virus infectivity and hemagglutinating and complement-fixing antigenicity. Cytoplasmic immunofluorescence was also detectable in the throat smear of pups experimentally exposed to reovirus aerosols. The fluorescent antibody technique seemed to be a useful means for the rapid diagnosis of reovirus infection when applied to field cases.

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Normal adult horse serum was analyzed by electrophoretic and immunoelectrophoretic methods. Seven different protein bands were found by cellulose acetate electrophoresis, 20 fractions by polyacrylamide gel electrophoresis, and a total of 20 antigenic components by immunoelectrophoresis developed with antiserum to normal adult horse whole serum. Changes in the serum proteins, especially the immunoglobulins, IgG, IgG(T), and IgM, and fransferrin, with the advance in age were determined by electrophoretic analyses and a quantitative immunodiffusion method. Precolostral foal serum was almost entirely deficient of immunoglobulins. Very soon after the first ingestion of colostrum, the levels of IgG(T) and IgM of the foal reached a maximal level, which was lower than the mean adult level, while the IgG level of the foal generally exceeded the adult level. Transferrin level was within the adult range in the precolostral serum. It showed no significant changes with the advance in age. On the other hand, all the three immunoglobulin classes and transferrin were high in level in the colostrum collected immediately after parturition, but decreased in level rapidly with the lapse of time after parturition.

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The migration layer (Migr.) developed from the neural epithelium of the fowl cerebellum was investigated on the basis of Rudeberg's findings [22] in various vertebrates. Migr. A, the first migration layer originated from the neural epithelium, appeared in stage HH 19-20 (ca. 3-day-old embryo). Migr. B was formed in stage HH 27 (ca. 5-day-old embryo) when Migr. A was divided into a dorsal cell mass, A₂, and a ventral one, A₁. In this stage A₂B was also formed between A₂ and B. As in mammals, B₂ in stage HH 30 (ca. 6.5-day-old embryo) and B₃ in stage HH 31 (ca. 7-day-old embryo) differentiated from Migr. B. These results obtained from birds agreed with those reported in mammals, except that any portion corresponding to B₄ in mammals was not found in chick embryos examined. The external granular layer differentiated from A₂ in stage HH 29 (ca. 6-day-old embryo). The superficial portions of B, B₂ and B₃ condensed into dense areas, which served the primordium of the ganglion cell layer. The borders among them were clear at the interruption, but became gradually indistinct after stage HH 38 (ca. 12-day-old embryo). Then the cerebellar cortex showed such uniform pattern of histological structure as seen in adult animals.

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