A 2-month-old Chowchow male sneezed frequently with puric discharge of low viscosity from the left naris. Asmear of the nasal discharge contained spirochetes, in addition to many neutrophils and epithelial cells and a few bacilli. The spirochetes weer 18, 06μlong and 0.48μ wide on the average. In them, the average number of rotations was 3.1 and the average length and depth of a rotation were 3.94 and 1.34μ, respectively. From the morphology and tinctorial properties, they were presumed to belong to the genus Borrelia. When the dog was treated with chlortetracycline, the spirochetes disappeared from it and recovery took place.
Trichomonads were isolated from a puppy in Sapporo, Hokkaido. The puppy was suffering from diarrhea of unknown etiology. The organisms had 5 anterior flagella of almost the same length, an undulating membrane extended to the tail, and a free posterior flagellum and were identified as Pentatrichomonashominis (DAVAINE, 1860).
In October, 1970, 130 cattle of the Aberdeen Angus and Hereford breeds were imported from the United States and held under quarantine in Yokohama. Twelve of them manifested fever, nasal discharge, lacrimation, corneoconjunctivitis, foamy salivation, coughing, pustulation, erosion, and ulceration of the nasal mucosa, and anorexia. Samples were collected from nasal and ocular discharge and blood of these cattle and inoculated into bovine kidney and testis cell cultures. Ten and nine strains of virus showing the same cytopathogenic effect were isolated from the kidney and testis cultures, respectively. Of them, six representative strains were identical serologically. Healthy cattle inoculated with the isolated virus exhibited the same symptoms as the spontaneously infected ones. Virus was recovered from their nasal and ocular discharge for 3days. The cross neutralization test between the isolated virus and the Los Angeles strain of infectious bovine rhinotracheitis (IBR) virus gave such results that it was possible to identify the former as IBR virus.
An antibody survey was conducted on three groups of swine inoculated with one and two doses of hog cholera livve vaccine and with inactivated and live vaccine, simultaneously, respectively. It revealed that the neutralizing natibody (NA) production after inoculation was affected considerably by the maternal antibody (MA) titer determined at the time of inoculation. In the one-dose inoculation group, NA was produced to the utomst to persist when MA titer was lower than 1: 4 at the time of inoculation, but did not increase in titer when MA titer was higher than 1: 64. In the two-dose inoculation group, NA titer increased to persist after inoculation with the second dose even when MA titer was 1: 64 or higher. In the simultaneous inoculation group, composed of adult sows on breeding, the decrease in NA titer was very slow, remaining in the order of 1 to 3 tubes even 18months after inoculation. In piglets, MA titer was reduced to half in 8 to 11 days. It was presumed that the difference in MA titer among the piglets of the same litter might be in the orderof 2 or 3 tubes. These results indicate that it is desirable to perform the initial inoculation of live vaccine at the age of 60 to 65days. It is necessary to carry out booster inoculation in piglets which are assumed to have a high MA titer.
A total of 752 antibiotic-resistant strains of Escherichia coli were isolated from the feces of pigs 2 to 4months old in 3 specific-pathogen-free swine herds in May, 1971. Of them, 366 (49%) cultures which carried various resistance pattern of R factors were examined for sensitivity to carbadox, a new synthetic antibacterial agent, using the agar plate dilution method. The minimum inhibitory concentrations of carbadox were 3.13mcg/ml against 3 strains (0.8%), 6.25 against 17 (4.6%), 12.5 against 121 (33.1%), 25 against 182 (49.7%), and 50 against 43 (11.8%). No cross-resistance was observed between carbadox and anitbiotics, such as streptomycin, chloramphenicol, and tetracycline.