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The kcag quality of Ut swine tysielas living vaccii4 wet tyjr, which has ken wty used in Taiwan is effec& only within one and a half months aft pseperanca It is of urgait rrxs1ty to imow the Ixeping quality of the vaccine by ftn.drg so that it may & appthl effirly to jntticlal nxpces, the studies ha’ been made since l%l. The results obtasiM during Ut last three years aie repoiled as follows
1. Selation cidrying media Asrsing various drying media studied, via slomrnilk powdes, lacae, dried yeast exni, slUmmed fresh milk, normal hoist serum, egg yolk and nutient hcith, skimmilk pow&r-dn& yeast enzt mnuuxe at the ratio of 1015%: 5-10% indistillerl wat was found toUt tnt at theprcceases of pre fxnt dqin w.i stoiige pericds,
2.Keeping quality of Ut vacase The vaccine made in Ut slarrunilk-yeast ernct cccnbined rnezhurn retained more than ‘O% viable cells aft 6 months and more than 45% eei after 12 months of coki storage. However, the keeping quality at room tnerahues were highly variable knding on the &gr of the tnpaatuses. It kept about 50% viat* cells aft3 months ofstorngeuxwina(14-25t)andonly 30% aft2 ks of storage in summer (29.34t).
3.Immmogenicity of the vaccine When iesi in mice, dqendakk immunity couki be o1aanM only when the rax.’nsntutl vaccine cxntaijtl mcce than 50 million viable cells and 20 mil&n cells were found to be Ut minimun eftiw dote, The vane was quit safe for the mice and Ut mice growed well and gained waght during the 14 day oler-vation ercd aft Ut lnt-aentonea] inpztion of 0.5 ml. (more than 50,(IflCU) viabk cells int1 ) of Ut zetnstxnstl vaccine.
4.Mdthon of aluminum hydroxbie gel With a&ling aluminum hydronle gel at the concentation of 2 ,Smg r ml. of broth cuolure of attua Erystlotlea insidic$atke used for Ut teprsepera4on, it was foutitgaveonlyhttle effect on Ut surinvai rat of Ut brct’ria. it took about 3houas to ixthpnat Ut aise subtance i.e. Ut insoluble o:wporat ‘ate thcronghly removerl siia Ut pxtipatat sho’a a clear demarcation and facilitat Ut recoty of purer bacerta afftfurthercenirifugaton
5.Pzefrrg: No diffrrencn were found wittier Ut oiving vaccine to be dried was ruefrl at-25tD deep fnr for 4 hours or at -?StD dry ar-ahol bath for one mime. Abut 15-20% of Ut viable cells were ktt during pre-fmng and abort 25- 40% during drying woinses.
6.Safety for swine Though Ut coojrxations of Chang-Hwa Prefecture Aaal Disse Diagiatic Cents, TIe frld ayeriznent ctthe dried vaxiie (ThaI Lot No.7,130 million viable cells jn ml. contamed) were cairn csit in June this 3r (19). Of 243 he&I of small pigs vaccinan with 1 ml. of Ut tial vaccirealoz 3 pigs (12%) shower! only slight reaction. And oUtr 1,244 small pegs vaccinatsi simultnously both with 0.Sml. ofUt tial vaccine and 2m1. of frcan-drnl lapiniad hog cholera vaxine, of therm 20 pigs (16%) shows! some reactions i.e. among thcGe 2) pigs, 12(0.96%), 2 Q116%) and6 pigs (0.84%) showerislight, morkrat and see era resativdy, and Ut oUtrs withont any tenon, and all of thcee tea! pigs were recowied within Ut observation itrnl of two weeks aft vaccinatica From these result, it can be said that this ficcen-drel swine erysipelas living va-cOne is quit safe for swine.
Note：Tleoutlineof this arrwas readtrf& 1963 theAunual MeenngofUt Taiwan Association of Animal Husbanduy and Vetrinary Medicine
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