Poultry sector is very useful for humans in terms of production of food items like meat and eggs. Pakistan has a developing poultry sector and is the second important sector after the textile industry. The poultry sector is encountered with many challenges; among them is the high incidence of disease outbreaks that result in colossal economic losses. The diseases of commercial and rural poultry include Newcastle disease (ND), infectious bursal disease (IBD), fowl pox, Marek’s disease, infectious bronchitis (IB), avian influenza, hydropericardium syndrome, etc. The disease outbreaks have also occurred in vaccinated flocks. Better understanding of the causes of vaccine failure will result in identifying prophylactic measures regarding disease outbreaks in poultry flocks. This chapter overviews the common causes of vaccine failure and further highlights the procedures for successful immunization.
Part of the book: Immunization