Komarov suş'u ile hazırlanan ve burun - göz yolu ile tatbik edilebilenaşının parantal immüniteye malik 48 saatlik ve 21 günlük civcivler üzerinde muhtelif dilüsyonlarının kontrolü, muafiyetin teessüsve devamı, revaksinasyonun önemi ve aşının muhtelif şartlaramukavemeti üzerinden durulmuş :ı) Aşının % 1 dilüsyonunun her iki gurupta da iyi çalışmadığı,buna mukabil kesif dilüsyonlardan bilhassa % 30'un en uygunolduğu,2) Muafiyetin 4 üncü günde başladığı 15 inci günde tamamenteessüs ettiği ve 4 üncü aya doğru kırılınağa başladığı,3) Burun- göz yolu ile aşılanan civcivlerin 3,5- 4 aylık olduklarızaman par- enteral yolla revaksinasyona elverişli bulundukları,4) . Bu aşının 37• C. da 2,5 ay; 18- 22° C. da 4 ay ve + 4° C. da9 aydan fazla müddet muhafaza edildiği tesbit edilmiştir.

Newcastle vaccine was prepared from Komarov's strain. The experiments, this vaccine was applied by the intra - ocular and intranasal routes of 48 hour and 21 day old chicks which were from immunized with Newcastle disease vaccine The vaccine virus of Newcastle disease was diluted as 1 %, 10 %, 20 %, 30 %,40%,50 % using Kaschula's solution (Formula: Glycerine + ı /8000 Sol. of crystal violet). Forty- eight hour old chiks were devided into 6 groups so that each group contained 15 chicks. Also, the same procedure was followed with the 2ı days old chicks.With each dilution of vaccine, one group from 48 hour and one group from 2ı day old chicks were inoculated with 0,05 ml. by intraocular and intra-nasal routes. To both groups control chicks were added. The results of the experiments were as follows : 1 - It was found that 48 hour and 2ı day old chicks which received 0,05 ml. of ı % vaccine virus, There were no Hİ anti- bodiesand after challenging they all died.2 - a) In the 48 hour old chicks, the immunity had started on the fourth day of the vaccination and lasted for about 3 months.b) However in the 2ı day old chicks, the immunity started on the forth day of the vaccination and lasted 4 months.3 - Forty .- eight old chicks were revaccinated by parenteral route using Iive Newcastle disease vaccine 3 months from the first vaecination and 21 day old ehieks were revaeeinated 3,5 months from the first vaecination. Twelve day after revaeeination, blood samples from all ehieks were drawn for the HI test and they were ehallenged with a pathogenie Neweastle disease virus. In all ehieks, it was found that the titer of the HI antibodies inereased immediately and they were resistant to ehallenge.4 - Ten % and 30 % dilutions of this vaeeine were kept at 37° C, 18-22° C. and + 4° C. Time to time, their haemagglutinating ability and the infeetivity for ebieken embryos were tested. It wasshown that the HA titer and the original infeetivity for ebieken embryos of both dilutions of the vaeei;ı'ıe virus persisted for 2,5 months at 37° C, 4 months at 18- 22° C. and 9 months at + 4° C.