Relationship between routes of vaccination Against newcastle disease and velogenic viscerotropic newcastle disease shedding in chickens

- The highest protection was (45%) afforded by intramuscular vaccination in birds challenged 3 weeks post -vaccination by intranasal route •While the oral, intracloacal and intranasal routes of vaccination showed the least protection (401 , 201 and 51)respectively •2 - The highest protection against ND (100/) could be obtained by intracloacal vaccination in birds challenged 2 months post vaccinaton 0While the intamuscular, oral and intranasal routes of vaccination showed lower percentages of protection (701 t441 and 331 ) respectively •3 - Most challenged birds after different methods of vaccinationdemonstrated a considerable increase in HI ti ters, the degree of response varied according to the route of vaccinat- ion and time of challenge 0~ - It is noticeable that birds ~accinated by the intranasal routedemonstrated a considerably high HI tit.ers (640) in comparison to other vaccinated groups that challenged 3 weeks or 2 months afterve oc Lnatd.on •5 - Virus exc’reatiol,l: after challenge of different vaccinated