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[in Japanese]

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Growth of equine infectious anemia virus in equine leucocyte culture is influencedconsuderably by individuality of horse from which the leucocytes were derive. It alsoinfluenced by bovine serum which is contained in tissue culture medium No. 199.The relationship between the percentages of the serurn protein fractions o btainedby paper electrophoresis and the results of leucocyte culture was investigated to elucidatethe nature of the most adequate serum for equine leucocyte culture.As a result, the percentages of the albumin and the beta-globulin fraction were low, and that of the alpha-globulin fraction was high in such sera as considered adequatefor equine leucocyte culture.To obtain a serum sample which has the nature described above, the serum sampleshould be collected aseptically. it should not be filtered through a bacterial filter.If a serum sample is not filtered but heated at a proper temperature for a propertime (50 -60C, 30 -40 minute), it will give good results irc leucocyte culture.

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Close inspection reveals certain irregularities in daily milk yields in a cow. ll-)(jdia?ram uiven in Fi?. 1(I) shows a fairlv irregular cJnan?e in lactation, while it exhibitsa eeneral tendencv to show a smooth, flowin? increase and/or decrease. Stactsttcattreatment seems to be a best method to disentanule such at>rarentlv complicated seriesof varieties. Time serial analvses of successive milk vields were conductect on true aatasiven in Fi?. 1(1) in the followinu manner: An arithmetic movin? averawe of 31 days wascalculated for the oriuinal series of vields to obtain the r>lots of Fi?. I(2). The plotsof movin? average revealed a ratcid increase after rcarturition, a rise to its highest pointin a few months later, and a ?radual decrease to its termination as the calf grew. Theseries of riots in Flu. l(3) rerresents the remainder obtainccd bv subtracting the series ortclots in Fi?. l(2) from the oriuinal series in Flu. l(l). Thus, the oriuinal series of milkyxelds XVIS dlV1dC)d 11l1t0 tXV0 sernes; 011(If serues presennts the undulatory Ch2LIlg durtng awhole lactation time, and the other the temtcorar>or stcontaneous change. The tatteris a chaotic temrorarv chan?e and mav be divided further into two or three componentsof fluctuation>each of which has a rather different length of r>eriodicnty as aeterrntneaby the adequate mathematical procedure in the time serial analysis.If the isolated components are called the annual, monthly, weekly, and dailyfluctuatmOn 111 the order Of the respectmve PCIl0dlC tlllltt It IS P0SS1bIC [0 unravel suchcomplicated outside-world influences as climate agents, food intake, and bodily exerciseupon the rnilk secretion of a cow.The t>resent rarer is esreciall>concerned with analvtical consideration on tt-merelationship between the apparent spontaneous change of daily lactation and the air-temperature possibly functioning on it.l) The diasram of successive chances of dailv milk vields and averaue air-temperaturewas decomposed into the above-mentioned four types of fluctuations by 3) Influences of air-temperature i.e. heat condition upon the changes of lactationmay be determined by visual comparison of the phase between both components offluctuation having a similar periodic time, or otherwise by calculation of correlationcoefficients between the corresponding fluctuations of similar periodicity. It is a matterof course that the year-long change of both has been previously eliminated from theoriginal values.4) The above-mentioned technique of analysis was actually applied to the discus-sion in the present investigation. The subjects used were the daily milk yields offour Holstein cows kept on the Livestock Farm, University of Tokyo, in Ibaraki Prefectureand the records of daily average air-temperatures measured at the Meteorological Stationof Mito, 14 kilometers away from this farm. As a result, it was found that air-temperature above 20C in summer and below 5C in winter acted as a depressingagent on milk yield for the following one or two days. Furthermore, the day-to-daymilk yields joined alternatively with one another ; that is, any two adjacent milk yieldsmaintained a certain negative relationship in their absolute values.

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A total of 436 strains were subjected to a taxonomical survey. All of them wereof spore-forming, obligatory anaerobic, Gram-positive or negative catalase-negative rods.Of them, 418 strains had been isolated from the feces or intestinal contents of black Neo-pards, leopards, tigers, cheetahs, pumas, jaguar, chickens, horses, cattle, pigs, dogs, cats>rabbits, ferrets, guinea pigs, mice and seal, lesions in horse and cattle, the tonsils of dogs, the uterus of cattle, soil, and silage, the remaining 18 strains were named stock cultures.The results obtained were as follows.l. The genus Clostridium was divided into four sub-genera, sixteen groups, on thebasis of four characters ; namely, the shape of the spore, rnotiNity, liquefaction of gelatin, and the growth type in iron-milk medium.2. Further studies are necessary to achieve the classification of this genus by thebiological and serological features, pathogenicity, and source of origin.

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