Crude protein influences in the bone mineral density of broilers aged between 7 and 28 days

Bone densitometry is an examination made for the purpose of measuring bone density to estimate the risk of osteoporosis or possible fractures. It's currently performed in humans and has been introduced in the zootechnical area in order to monitor the development of animal bones. Assuming the hypothesis that the protein deposition influences body and bone composition of birds, we had intent to set, for birds, the real results of a high protein diet. Therefore, this study aimed to analyze different percentages of raw protein on mineral density in broilers. 720 Cobb500 chicks were used, they were one day old (360 females and 360 males) distributed in experimental design completely randomized in a factorial of 3x2 with 3 treatments and 6 repetitions. The birds were fed with 3 treatments: reference feed, feed with high raw protein and low raw protein. Bone densitometry was performed on a DXA machine (DualEnergy X-ray Absorptiometry) brand Hologic when the birds were 7 and 28 days of age, data of bone mineral density, body area and total mass were obtained. The data were analyzed by analysis of variance using the software JMP(R)11. There were significant effects (P <0.05) to the total weight of the birds with 7 and 28 days of age, and about the bone mineral density only to the birds at 28 days of age. The total mass for both age groups was higher for chickens fed with high crude protein diet. For bone mineral density, the male broilers fed with high crude protein had higher value. The presented results show that the diet with high protein was more satisfactory, and can, therefore, be concluded that this diet improves the body structure of the birds.