Abstract—An experiment was carried out to evaluate the effects of fasting and early diet composition on broiler chicken's development. A totally of 540 one-day old male broiler chicken were used in this study. The treatments were Control (C), fasted for 24 h (24F), fasted for 48 h (48F), feeding a diet containing 15% egg powder for 24 h (24E) or 48h (48E), feeding a diet containing 20% glucose syrup for 24 h (24G) or 48 h (48G), and feeding a diet containing 15% egg powder and 20% glucose syrup for 24 h (24EG) or 48 h (48EG). At 21 days of age, feeding G diet for 48 h resulted in longer duodenum and ileum than other treatments. In addition, longer (P<0.05) jejunum length was found in chicks who received the GE diet in the first 48 h. feeding E diet for 48 h did increase ileum weight significantly. At day 42, the 24G diet fed chick was found to have the highest duodenum and ileum weight. The results for morphological parameters show that feeding a diet containing egg powder and glucose syrup for 48 hours resulted in higher duodenum crypt depth (CD) in comparison to chicks fed with diet containing egg powder for 48 hours. No access to feed for 48 hours decreased duodenum villous height (VH) and increased (P<0.05) duodenum CD and subsequently decreased VH: CD ratio on day 7. Feeding a diet containing egg powder and glucose syrup for 24 hours resulted in longer VH and lower CD and subsequently higher VH: CD ratio in duodenum on day 7. On day 21, none of experimental treatments could affect the morphometric parameters of duodenum and ileum. Feeding EG diet for 48 h resulted in longer (P<0.05) ileum VH and higher VH: CD than chicks fasted for 24h on day 7. In conclusion, the present study showed that the diet composition affects chick development post-hatch and feeding a semi-moist diet with high protein and suitable energy levels containing egg powder and glucose syrup for 48 hours post-hatch is beneficial for post-hatch growth and considerable performance benefits than
