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Lzpini2rd hog cholera virus has keen widely userl in Taiwan for conteting hog cholera more than ten yars since 1954. It has keen found that some post-vathnal reactions have keen encountered on a small portion of vaccinated snail pigs.
In order to obtain safer but highly immunoginic seer! virus for the gcduotion of vaccine, attempt were made to ssage the lapiniarI hog choler virus (LFC stain) in goat according to the technique of Sasahara and his asscciates. At present, 57 ssages havekeennarkthepresenlas folliws:
1.Urge amount of the virus, i.c.,50 ml. of 10%emulsion of lapiniali hog cholera virus infect! spleen of the EO)th rabbit ssage was injxt! intravenously inta goals, and could ke easily :essagec1 serially in goals using goat spleens. Pigs intl with one ml. eachofoneor 10% emulsionofgoat spleens takenat the 4,8,14,2224,31,36 and 45thessages were successfully immuniad against 1 ml, of 1% hog cholera virulent blood,
2.The incculun for ssage after the 27th goat ssage was reducer! to Sml. and found that the virus could have ken pessaged serially in goat. One ml. each of one or 10% spleen emulsicns made at the 27+1 Sand and27+23rdssages conferred solid immunity to the pig incculat!.
3.The virus titers in various organs a at the 31st and the 27+27thssages were comparable to that found in those organs of the LPC stain infected rabbit, i. c. spleen and lymph nodes containerklO-5, liver <10-3 and defibrinatl blcxxl 10-3pig immunizing unit ofthe goat virus.
4.Safety test. Twenty ml. each of the 10% emulsion of spleens and lymph nodes a at the 31st and 36th goat passages was intedinto2and 4 head of small pigs reseotively. All but one pigs tolerat! well with no untoward signs of illness, They were all solidly immune. The adapt! stain was shown to much safer than the lapinizd virus when int! to swine.
5.Up to the present, 150 goat had ken used for the virus passage. Of them, 29(193%) and 12(8%) showed slight and moderate fever reaction resjtDtively while 109 (72.7%)retainodnoreaction. Of39headofrabbits inccuiaedwithtwo. mlof the 10%spleen virus of the infected goat, 71.8% showed apparant fever reac-tion which are comparable to that found in the LPC strain infected rabbit.
Note: The Outhne of this paper was read kefcxre the 1936 Annual Meting of the Taiwan Asscciation of animal Husbindry and Veterinary Medicine.
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