A culture medium contained in a cylinder was devised to simplify the test in food inspection. Since it was used with ease in the field, some part of the technique for the laboratory test could be saved. When a selective medium was employed for a sample, it was possible to observe the state of contamination with a given pathogenic organism, without alteration, in the cylinder. The new method was not so inferior to the swab method or the paper coli test in the rate of detection of contaminating organisms. It wa regarded as an effective method for screening test in the field.
In September, 1971, bovine epizootic fever (BEF) occurred collectively in Okinawa and the northern part of Kyushu, Japan. A total of 4, 204 cattle were involved in this part. BEF virus was the main cause of the occurrence. In addition, bovine RS virus, bovine adenovirus of type 7, and parainfluenza virus of type 3 induced the respective infection independently or mixed infections. Four strains of virus were isolated in suckling hamsters (SH) and 3 strains in suckling mice (SM) from blood of 4 infected cattle in Nagasaki Prefecture, and one strain was isolated in SM from blood of 4 infected cattle in Okinawa Prefecture. An attempt failed to isolate virus directly in HmLu cells. Two strains of virus isolated already in SH and SM, however, were adapted successfully to these cells. Detection of neutralizing antibody against BEF in SM showing no clinical symptoms or in 3-week-old mice inoculated with a sample for virus isolation made it possible to demonstrate the occurrence of viremia in infected cattle indirectly.
A survey on Marek's disease (MD) was conducted on the K Poultry Farm in Hokkaido over a period of 210 days beginning with the day of hatching. A total of 7, 287 chickens of strains No.731 and No.522 of High Line were surveyed and 892 dead and diseased birds examined pathologically. The following results were obtained. The Selection rate was 12.24% including dead and condemned (birds) and the breeding rate 87.76%. The incidence of macroscopically diagnosed cases of MD and lymphoid leukosis (LL) was 10.40% (758/7, 287), and that of histopathologically diagnosed cases of MD 70.18% (353/503). The lesions of MD were classified as follows: Type TI, 11.13% type TII, 27.44% type TIII, 4.77%, and type R, 26.84%. The incidence of LL was 8.55% (43/503). LL was found among birds 120 or more days old. The striking feature was a high incidence of visceral lymphoid tumors particularly those accompanied by swelling of peripheral nerves. Lymphoid tumors were found in the liver, spleen, proventriculus, lungs, ovary, kidneys, thymus, serosa, intestines, heart, skeletal muscles, bursa of Fabricius, adrenal glands, pancreas, and mesentery in the order of severity. The peak of occurrence of MD was found among chickens 90 to 180 (usually 140) days old. The gel precipitin reaction of MD was negative in 8.96%. In addition to lesions of MD and LL, 4 cases of nephroblastoma, 3 cases of myosarcoma, 3 cases of coli-granuloma, 2 cases of serositis, and 1 case of skin mucormycosis were observed.