MVSc

Under controlled conditions, the effect of Ascaridiasis on Newcastle disease vaccination was investigated. Haematological studies revealed reduction in erythrocytes, haemoglobin, serum protein, heterophils and basophils and an increase in leukocytes and eosinophils in A. galli infected birds. Post – vaccinal reactions, mostly of a paralytic nature, were observed in 25 – 30 per cent of the infected birds. The immune response of birds to Newcastle disease as revealed by the HI titres, is reduced by A. galli infection, the magnitude of reduction being related to the severity of worm burden. Although, all the birds resisted challenge, A. galli infected birds developed a mild form of disease. The need for routine deworming of birds before vaccination is stressed.