Abstract

In this paper the effects of a Chinese formula Maxing Shigan powder were investigated on IgA-secreting cells of chicken bronchus. The herbal powder was dissolved in water at three dosages, 0.5, 1 and 1.5 g/L. Each dosage was given to 15-day-old chickens which were challenged with infectious bronchitis virus (IBV) by artificial infection for 3 days. Then thetherapeutic effects were detected. The chickens were sacrificed at 18, 21, 24, 27 and 30 days old. The changes of IgA-secreting cells per unit area of bronchus were measured by immunohistochemistry. The IBV antibody titers in serum were determined by ELISA. The results of the therapeutic effects showed that Maxing Shigan powder can significantly reduce the mortality and enhance the recovery rate. Positive expression rate of bronchial IgA-secreting cells and higher IBV antibody titers were observed in the herbal treated groups. The results suggest that Maxing Shigan powder can protect the mucosa of IBV chickens, promote IgA secreting cells recruitment in the mucosa and secretion of the IBV antibody so as to lower the mortality and elevate the recovery rate of the IBV infected chickens.

Key words: Maxing Shigan powder, infectious bronchitis virus, IgA secreting cells, antibody.In this paper the effects of a Chinese formula Maxing Shigan powder were investigated on IgA-secreting cells of chicken bronchus. The herbal powder was dissolved in water at three dosages, 0.5, 1 and 1.5 g/L. Each dosage was given to 15-day-old chickens which were challenged with infectious bronchitis virus (IBV) by artificial infection for 3 days. Then thetherapeutic effects were detected. The chickens were sacrificed at 18, 21, 24, 27 and 30 days old. The changes of IgA-secreting cells per unit area of bronchus were measured by immunohistochemistry. The IBV antibody titers in serum were determined by ELISA. The results of the therapeutic effects showed that Maxing Shigan powder can significantly reduce the mortality and enhance the recovery rate. Positive expression rate of bronchial IgA-secreting cells and higher IBV antibody titers were observed in the herbal treated groups. The results suggest that Maxing Shigan powder can protect the mucosa of IBV chickens, promote IgA secreting cells recruitment in the mucosa and secretion of the IBV antibody so as to lower the mortality and elevate the recovery rate of the IBV infected chickens.

Key words: Maxing Shigan powder, infectious bronchitis virus, IgA secreting cells, antibody.