Bursa was collected from 51 White Pekin ducklings from day-old to 155 days of age. The body weight and weight, length and diameter of bursa were measured after examining its gross appearance. The bursa could be seen as a smooth, yellow elongated blind sac like structure with a tapering apex in day-old bird. By 155 days it became a cylindrical and much reduced pale structure. The number of plicae in the inner luminal surface, increased upto 30 days of postnatal life. After-80 days a decreasing trend was observed. After hatch, the bursal growth rate was not in proportion to that of body. It showed a decreasing trend after attaining peak values at five days of age. The weight, length, and diameter of bursa attained maximum average values at 58 days of age. At this age the bursa may be said to be at its peak functional activity.
White Pekin duck, bursa, postnatal development
