A STUDY ON CONTAGIOUS PLEURO-PNEUMONIA OCCURRED IN IMPORTED CATTLE

Abstract

Contagious pleuro-pneumonia is due to an extraordinarily small, filtrable, but visible and polymorphous micro-organism called Asterococcus mycoides. The virus of this disease has already been investigated by Pasteur, Nocard and Roux, Lipschutz, Borrel, Martzinoski, Bordel, Dujardin-Beaumetz, Jeantit, Jouan, Giese, Freiberger, Laquerriere, Schutz, Steffen, Siedamgrotzky and Noack, Miesser and Beitzen, Poppe, Albrecht, Schochowsky, Leusch, Titze, Dahmen and many others.It is stated that the disease was first observed in Hesse in 1693, and that its ealiest appearance as an epizootic was in the end of the 17th century when it prevailed chiefly in Switzerland and the neighboring countries of Germany and France.According to Barker, the disease appeared in England in 1736 and in France in 1765. At the beginning of the last century an outbreak occurred in Belgium and Holland and caused a great losses. Austria was first infected in 1841, Hungary in 1891, Belgium in 1882, Australia in 1858, South Africa in 1854, Sweden and North America in 1843 and Turkey in 1888. In Asia the discase is wide-spread, especially in Russia and in India. Japan has been quite free from the disease till September, 1924, when the author discovered 3 cases in Yokohama Quarantine Station. This report is_ based on those cases occurred among 42 Mongorian cattle imported from Dairen, China.At antopsy of the 3 cattle the pathological changes characteristic to the disease were observed.In the calf No. 1 inoculated with 15c.c. of lung juice taken from one of those cadavers developed after 10 days of incubation acute symptoms of pleuro-pneumonia and death occurred on the 11th. day.The calf No. 2 inoculated with 15c.c. of pleural exudate died of the same disease. The period of incubation was 3 days and the course was 21 days.The calf No. 4, inoculated with the pure culture from the pleural exudate of the calf No. 2, was also fallen to victim. Its incubation-period was 2 days and the course of the disease was 18 days.In each of those three experimental cases mentioned above the typical pleuro-pneumonia developed, but in No. 2 and No. 4, which were sucklings, remarkable inflammatory swellings were observed in joints, and also in subcutaneous or intramuscular connective tissue surrounding the point of inoculation. These symptoms were also noticed by Tartacowsky and Dchownkowsky.The histological appearance of the lungs in those three experemental cases, were almost alike, namely, a progressive interstitiial pneumonia with secondary hepatization of the lungs was observed in each of the cases.The author succeeded in isolating and growing an extraordinarily small polymorphous micro-organism from the pleural exudate and proved that this micro-organism was filtrable, and was stainable with Löffler's flagella stain and by Giemsa's method, while not stained by Gram's method and also that the organism was visible under a magnification of more than 1500 times.The organism grew slowly in beef bouillon or Martin's bouillon, containing cattle or horse blood serum. In liquid media, the culture produced after 2 to 7 days a slight turbidity which was noticeable as a silky cloud by passing an electric light, while on the solid media, it formed very fine transparent whitish colonies (1-2m.m. in diameter) in the course of 4 to 9 days. The colonies were quite adherent to the surface of media and had a greyish point in the middle of it.The organism was aerobic and its optimum temperature was about 37°C.In no case the author could succeed in growing the virus from the blood, but from the forgoing he concluded that this micro-organism can be recognized as Asterococcus mycoides.