Dogs experimentally infected with Diphyllobothrium mansoni were treated by a single injection with 100, 150, or 200mg/kg of palomomycin, an antibiotic of the aminoglycoside group. None of the doses revealed a perfect destruction of the worm, although the larger the dose, the better the anthelmintic effect. Even dogs injected with 200mg/kg demonstrated the high safety of the antibiotic in the clinical and laborato examination, suggesting that this drug might be available as an anthelmintic in future.
A pregnant sow gave birth to 12 piglets about one month after introduced into a farm. The young died suddenly with symptoms of blooding from the anus and prostration within 19 hours. Immediately after death autopsy was performed on four of them to collect materials for microbiological and pathological studies. Clostridium perfringens was isolated from all the intestines and C. sordellii and C. paraputrfcum were from some intestines in the order of 106-7/g. These microorganisms also were found in some parts of the animal body. By the neutralization test with anti-C. perfringens type A serum, 15 C. perfringens strains belonged to C. perfringens type A. Their toxin titers reached 0.05 to 2.5 u/ml by Evans's method. Toxin was also shown in the intestine of a piglet. There was, however, discrepancy between the presence of toxin in the intestine and the isolation of toxic C. perfringens type A. Pathological specimens of the intestine showed the image of necrotic enteritis. The disease was diagnosed as necrotic enteritis with bacteremia with C. perfringens accompanied with C. sordellii, C. paraputrificum, etc. Epidemiological discussion was made, since a similar disease occurred 6 years before.
For the agar gel immunodiffusion test, bovine leukemia virus antigen was prepared from persistently infected cell culture fluid. It contained envelope glycoprotein (gp) antigen and core protein (p) antigen, the latter being twice as much as the former. An antibody survey was conducted on 453 cattle in the field. In the test, the central well was filled with antigen, two surrounding wells were with positive control serum, and the other four with serum to be tested. As a result, when gp antigen was used after adjusting its titer to 4 units, the best results were obtained and both gp and p antibody could be detected. Both antibodies were very low in titer in the positive serum. Cattle positive for p antibody were only 19.7 % of those positive for gp antibody.
A meningiothelial meningioma, forming a very large spherical mass about 15# cm in diameter, was found on the head in a 12-year-old female Pointer. Four years before the first clinical examination, a tumorlike mass about 1.0# cm in diameter had been noticed in the occipital subcutaneous tissue of the dog. In 4 years it grew in to a size of infant head. On clinical examination, the tumor mass was so heavy that the dog could not keep the head in normal position. Radiography revealed that the mass was limited in the extracranial subcutaneous tissue and unrelated to the intracranial meninges. There were no distinct clinical signs. A biopsy specimen showed a typical pattern of meningothelial meningioma. About 9 months after the successful excision of the tumor, the dog died of acute pneumonia. At necropsy, three grayish white spherical tumor masses 1.0-2.0#cm in diameter were found on the surface of the diaphragm of the lung and diagnosed histopathologically as metastatic nests of the primary meningioma. The origin of these tumors was unknown. It was speculated that the tumorigenesis might be related to the history of the dog, which had suffered from some small shots in the occipital region in the course of hunt-training at 2 years of age.