Over the last five decades improvements in nutrition and genetic selection have reduced the time required to produce a 2 Kg broiler within 1.7 FCR. The neonatal period is defined as the first seven days of the production cycle after hatch. It is a crucial time when the chick requires special management and nutrition. Efforts to control metabolic disorders such as ascites and leg problems have led to recommending early feed restriction during the first two weeks post-hatch. Thus, it is essential to know the effect of poultry management practices on subsequent chick development. A paper presented in the ohio university explains the importance of the relationship of neonatal nutrition to muscle development. Muscle growth and development can be divided into two distinct periods: hyperplasia and hypertrophy.
Hyperplasia is an embryonic period characterised by proliferation of muscle fiber number whereas hypertrophy is a post-hatch muscle growth which results in the enlargement of existing muscle fibers. Nutritional deprivation has a significant effect on the myoblast cells. Research was conducted to evaluate the effects of an immediate post-hatch feed restriction on breast muscle formation. The increased number of nuclei in muscle fibers correlates with increased synthesis of protein and muscle fiber size enlargement. Myoblast cells are extremely responsive to the mitogenic effects of their environment, including nutrition. A 42-day length of study conducted with feed restriction on the neonatal chickens showed a significant difference morphologically in the development and structure of the breast muscle between the feed restricted and unrestricted diet treatments. It also increased deposition of fat in the breast muscle of the birds with the 20% feed restriction.
Nutrient deprivation in the first few days after hatch may interfere with normal muscle protein development in broiler chicks. However, if you believe that flavor and juiciness follow the fat, there may be some benefit from early feed restriction.