Pathogenicity ar?d immuxaogenicity for mice were compared among eighteen Ery-sipelothrix insidiosa strains which had been attenuated by serial passages on acriflavimtagar culture, and those for pigs among nine of these strains.In the early stage of attenuation, all the original virulent Erysipelothrix insidiosastrains lost their virulence to kill mice. Arthritis occurred to the hind legs in all thesechronically infected mice. In this stage, the attenuated organisms were well propagatedin these mice, autd arthritis was induced constantly by inoculation with even a few dosesof these organisms.With the progress in attenuation, the organisms lost their ability to produce arthritisin mice gradually, although they still retained the immunogenicity for mice which wasdemonstrated by challenge made with a virulent strain ten days after immunization, After further attenuation, these organisms were no longer propagated in mice, aztdlost their immunogenicity completely.Inoculated with the organisms which had constantly caused arthritis in mice, pigsexlxibited clearer "red patches" than those inoculated with the organisms which had notcaused arthritis in mice. They presented no other clinical abnormality during an observa-tion period of fourteen days after inoculation. The red patches disappeared within sevendays. These pigs survived against the challenge with virulent organisms, without mani-testing ar?y clinical symptoms during another observation period of fourteen days.Some of the strains had only a weak activity of producing arthritis in mice, but theysltowed a protection rate of more than eighty percent in mice against challenge with tltevirulent strain. They were proved to vary in degree of red-patch formation and give riseto only an insufficient immune status in pigs.After inoculation with strains which had lost an ability to produce arthritis or reducea protection rate to less than eighty percent in mice, no pigs were found to be immunxeagainst the virulent organisms.Tl?ere was 21 correlation between the immune statu

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The paternity test may be necessary even on pasturing beef cattle in order to clarifythe pedigree of offspring, find out a bull carrying undesirable genes resulting in givingbirth to abnormal calves, and study tlte breeding behavior of bulls in pasture.In this investigation, the efficiency of various blood grouping systems for paternitycases involving two or more bulls was estimated from gene frequettcy data in JapaneseShorthorn cattle. The results actually obtained are shown below.(I) The expected probability of making exclusion for paternity cases involving twobulls by nine systems of red-cell antigens was 0.705, artd that by live protein types was0.490. It increased to 0.850, however, when estimated by the combined use of all tlaesystems.(2) In paternity cases involving more than two bulls, the probability of makingexclusion was calculated from the following formula: P.zP.Cn=1>, where P. is the prob-ability of exclusion in two bulls and n is the number of bulls involved. In pasturingJapanese Shorthorn cows with five bulls, the probability of making exclusion decreasedto 0.522.(3) In nineteen actual paternity cases in pasturing cattle, including three possiblebulls, about 84% of the cases were solved by all the systems combined.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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The incidence of infectious nephrosis in young cJticks was first observed in Japan.The first clinical sign of this disease was a whitish or watery diarrhea, with vent featherssoiled by urinary unaterial. This was followed by anorexia, depression, trembling, pros-tration, and deatlt. Few or no respiratory signs were noted. Macroscopic lesions revealedmarked nephrotic changes in the kidney with the ureter swollen by heavy deposits ofuric acid.Infective agents were isolated from kidney lesions caused by inoculatior? with theallanotic fluid of infected embryonating eggs. Of them, one designated GN-2, wheninoculated intraocularly into susceptible one-day-old chicks, produced such typical kidneyIesions as found in field cases of nephrosis. When exposed to the infection by contactwith chickens inoculated with Late GN-2 isolate, one-day-old chicks presented similarclinical signs and Iesions. Fatality was higher in one-day-old chicks than 4- to 10-week-oldchicks. That agent was recovered from the kidney lesions of chicks which died.The allantoic flvuid harvested from second-passage eggs passed through rmilliporefilter GS (220 mp). The resulting filtrate caused similar lesions in one-day-old chicks.The Iesions evoked by agent GN-2 in embryor?ating eggs were dwarfing and curlingof the embryo and increased in severity with the advance in passage. Identification andcharacteristics in tissue culture of this agent will be mentioned in a paper to be publishedin the next number of this jotzrnal.

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