Duration of immunity that NDV and IB live vaccine give
I would be grateful if you tell me 1- The duration of immunity that NDV and IB live vaccine given in parent breeder 2-Sometimes I encounter by low NDV and IB persistence of immunity. What are the reasons? I would be thankful if there is a reference 3-I vaccinated my flock with Ma5 and clone 3 when I conducted Elisa to check the success of vaccination I found the titre of NDV is high. What is the reason behind that?
Thanks and regards.
Dear colleague,
1- the duration of immunity from ND and IB live vaccine depends on if it associated with an inactivated vaccine or not. If they are given alone the expected titer will be low and persistence will not exceed 3 to 4 weeks. But if associated with killed vaccine we'll obtain a high titer and continue for 6 to 8 weeks.
2- The short persistence of immunity may due to withering the inappropriate vaccine application or exposure to field infection.
3- The high titer more than the normal is due to field exposure which leads to shooting of the titer 2 to 3 weeks post challenge.
I hope that I could explain your questions.
Best regards
Mohamed Ali
Respected my colleague thank you very much for your comment.
Salah Mohammed
How are you, Sir? I would be grateful if you tell me when does the 6-8 weeks to be count from the start of injection of vaccine or the onset of immunity or the peak of immunity that the vaccine reaches.
Thanks and regards.
Dear colleague,
Would you please tell the routine vaccination program and method in breeding period for IB and ND?
Please regard that local immunity is far more important than circulatory immunity for IB and ND.
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