Viral Agents As Causes OF Mortality OF Chicken Embryos In Baladi Incubators =

Results obtained in this investigation oould be snmmnrised in the following :—1) 356 egg representing 10% of tot@ dead embryos during a hatching season were used to detect virus agents as a cause of their mortality.2) Thirteen groups treated materials were inoculated in chicken embryo vie yolk sac and allantoic—oavity for a better isolation possibility.3) virus isolation trials failed to detect IB, OBLO or AD infections in chicken embryos examined in parallel.4) Esemagglutinating agent could be positively isolated three times via allantoio inooulation and two times via yolk sac inoculation.5) serological identification reveal that these agents are Newcastlc disease virus strains as their HA. activity was inhibited using Kyper—mnnme serum against Newcastle disease.6) variation in the appearance of precipitating antigen among Newcastle disease virus strains isolated appears to be assooiated with the inoculation route.7) The factors jaflencing transmission possiblities of Newcastle disease virus via eggs is discussed.8) Pbs need for SPj fanis to provide egg for diagnostic purposes seems to be an utmost need in Egypt.