A set of resazurin paper was developed, so that the resaruzin test might be performed in a simplified manner. Then it was tested for capacity. A total of 100 samples were collected from milk contained in receiving milk cans at plant A in Tokyo. They were cultivated at 37, 30, and 20°C to study a correlation between the time required for the culture to be discolored and the SPC of raw milk.
As a result, the correlation coefficients determined with discs Nos. 5, 4, 3, 2, 1, and 0 at 37°C were -0.621, -0.591, -0.638, -0.722, -0.821, and - 0.817, respectively; those at 30°C were -0.551, - 0.620, -0.708, -0.807, -0.862, and 0.847; those at 20°C were -0.672, -0.774, -0.794, -0.804, -0.825, and 0.866. In short, with a rather high correlation, it was possible to estimate the SPC of a raw milk sample from the degree of discoloration determined by applying this set of test paper to the sample.

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Chickens 32 days old were vaccinated with the Hitchner B₁ strain of Newcastle disease virus through the drinking water under field conditions. They were examined for the immune response and safety.
1. Chickens vaccinated with 10^6.2 EID₅₀ failed to show any sympotm of respiratory disturbances.
2. After a single vaccination, the geometric mean HI titer (GMT) rose significantly to 36.3 within 6 weeks. It declined rapidly, reaching 3.6 6 months after vaccination. Similar results were obtained from chickens revaccinated at 62 days of age. Of chickens vaccinated with a single or two doses, 80 to 100 per cent resisted to intramuscular challenge with 10^4.7 EID₅₀ of virulent virus of the Sato strain over a period from 2 to 6 months after vaccination. Their immunity began to decrease 4 months after vaccination gradually. Chickens revaccinated at one-month interval exhibited a little better resistance to challenge than those given a single vaccination dose.
3. In chickens revaccinated 1, 2, and 3 weeks, 1 and 2 months after the first inoculation HI GMT showed no sgnificant rise. All the chickens resisted to challenge made 3 weeks later.
4. Chickens given the third vaccination dose 6 months after the second vaccination showed a higher HI antibody response than chickens inoculated with inactivated vaccine.
5. Of susceptible chickens put in contact with chickens inoculated with live virus, vaccine 43 to 80 per cent were infected after 5 to 10 days. Noinfection occur red among those chickens after 15 to 20 days.

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An exploration for the prevention of pig scours using pooled swine gammaglobulin was carried out with piglets 2-3 weeks of age on a farm in Saitama Prefecture. In it, 73 piglets received preventive injection and 63 piglets served as controls.
1. Pooled swine gamma-globulin was prepared from the blood of mature pigs on various farms in Japan. The antibodies against the pathogenic strains of Escherichia coli were found in it, as well as those against other various serotypes.
2. The difference in rate of incidence of scours between the treated and the control group was significant (P<0.05), the rate being 36 and 55 percent, respectively. In addition, the average duration of scours was 2.2 and 3.2 days, in the treated and the control group respectively (P<0.05).
3. The average body weight at 8 weeks of age was 13.8 and 11.7 kg in the treated and the control group, respectively. The difference in body weight between the two groups was also significant (P<0.01).

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