تاثير التمنيع بمستضدات الرويسات الاولية للاكياس العدرية في نمو ديدان المشوكات الحبيبية في الكلاب

Severe outbreaks of Newcastle disease often occur in areas of° intensive poultry production, which is reasoned mainly to break down in immunity. Although poor vaccine quality is one of several possible factors that could lead to vaccination failures (1).The failure of protection usually results from: (i) mycotoxin and/or drug induced immunomodulation (ii) cold or heat stress (iii) infectious agents (iv) malfunctioning of the host defense mechanism and (v) presence of high titers of maternal antibodies (1-7). Immunostimulation of a bird may lead to increased antibody production, increased cellular immune responses,