Effect of corn–soybean meal-based diets with low calcium and available phosphorus in male broilers on performance, tibia criteria and jejunum histomorphology

This study was conducted to determine the effect of reducing calcium (Ca) and available phosphorus (AvP) on performance, carcass yield, tibia traits and jejunum histomorphology in broilers. For this purpose, 480 one-day-old Ross 308 male chicks were distributed into four trial groups with eight subgroups. During the starter period, birds were fed with recommended or reduced Ca and AvP contents of 66.7 and 62.5 g/kg, respectively. Calcium and AvP contents of the groups were as follows: control: 8.70 g/kg Ca, 4.40 g/kg AvP for grower and 7.80 g/kg Ca, 3.90 g/kg AvP for finisher; LCP1: 8.30 g/kg Ca, 4.20 g/kg AvP for grower and 7.10 g/kg Ca, 3.50 g/kg AvP for finisher; LCP2: 7.90 g/kg Ca, 4.00 g/kg AvP for grower and 6.00 g/kg Ca, 3.00 g/kg AvP for finisher; LCP3: 7.00 g/kg Ca, 3.80 g/kg for grower and 5.00 g/kg Ca, 3.00 g/kg AvP for finisher. Performance variables have been calculated from the data of each period, and samples were obtained from the slaughtered birds on the final day of the trial (42nd day) for carcass and tibia traits and jejunum histomorphology. Reducing dietary Ca and AvP did not affect the broiler performance, carcass yield and mortality. Tibia ash decreased in LCP2 and LCP3 groups (P < 0.01). Villus width and villus surface area increased in LCP2 and LCP3. Overall, feeding with a diet 100 g/kg lower than the recommended Ca and AvP did not affect performance in broilers, but improved jejunal development.