EFFECT OF NUTRIENTS DENSITY ON PERFORMANCE OF BROILERS AND ITS CORRELATION WITH CARCASS CHARACTERISTICS IN GROWER PERIOD OF BROILER CHICKS

This experiment was conducted in order to investigate the correlation between different levels of diet nutrients in grower period on performance and carcass characteristicsof broiler chicks. The chickens were fed the same diet in starter period; later four diets with different levels of nutrients were used in grower period. The levels of metabolisable energy in the experimental diets were 3000, 3100, 3200 and 3300 kcal/kg. Diets used in the research are set according to NRC (1994). Furthermore, the ratios of all energy to protein were kept constant. The results showed that weight gain, feed conversion ratio and carcass characteristics were affected by different levels of nutrients. In addition, an increase in density of nutrients had a direct correlation with gain weight, and a reverse one with feed and carcass percentage. Finally, analysis of regression between carcass and nutrients density indicated that there were a correlation between nutrients density changes and carcass with increasing levels of nutrients. In other words, carcass percentage (r=97%), edible carcass percentage (r=95%), thigh percentage (r=92%) and relative weight of gizzard (r=91%) showed the highest regression. Feed cost per kg of meat decreased with lowest energy level (p<0.05). As a result in broiler diets using low density nutrients can be useful than high density nutrients.