PATHO-MORPHOLOGICAL CHANGES DUE TO RICKETS IN CHICKS

Ricket was produced by feeding vitamin-D low diet to 1-day-old broiler chicks. Ricketic changes developed from day 10 onwards. Chicks showed marked decline in body weight gain, increase in bone to body weight r atio and decrease in bone ash percentage. Biochemical changes revealed decrease in plasma calcium and phosphorus and an increase in alkaline phosphatase activity. Radiograph of long bones showed poor mineraliza tion. Growth plate of tibio-tarsus showed lengthened proliferating-pre hypertrophied zone (P-PHZ) and in metaphysis an increase in uncalcifie d bony tissues along with fibroplasia was observed. Parathyroid glands were hypertrophied in these chicks.