Balanço eletrolítico e suplementação de Vitamina “D” em rações para frangos de corte

Abstract

The experiment was aimed to evaluate possible relationships between supplementation with different vitamin D sources and different and different programs on dietary electrolyte balance due to its importance in bone formation and on broiler performances. 1.440 day-old chicks, males from Cobb-500 strain, from a commercial hatchery was used and housed in conventional breeding sheds, growth in bed with shavings. The adopted system was completely randomized design in a factorial design with eight treatments and six replicates of thirty birds per experimental unit. The studied factors were two levels / electrolyte balance programs (Normal - 220/210/200/185 m Eq/kg and High - 290/280/270/255 mEq/kg) in feeds, according to their phase (pre-starter, starter, fattening and slaughter) and four programs / additional vitamin D supplementation sources (1- without additional supplementation, 2- 2800 IU / feed kg of D3 vitamin, 3- 2800 UI/ feed kg diet of 25-OHD3 and 4- 80 IU / feed kg of 1,25 (OH) 2D3 from three sources of supplementation. According to the design phase, basal vitamin D supplementation was reduced gradually in all treatments (20% growth and 50% final) in relation to the initial supplementation. The diets were based on corn and soybean meal with phytase supplementation (1000 FTU / kg feed) reducing the levels of phosphorus available and calcium 0.15 percentage, the feeding program consisted on four feedss, which correspond the creation cited stages according to the recommendations from Bertechini et al. (2012). The evaluated data were performance, blood parameters, bone and carcass characteristics, as well as the litter dry matter. The performance of broilers fed a diet with levels of BEL within each RVSP affect the performance characteristics of pullets from (1 to 10) days, so that those that had their diets supplemented with high-BEL (290, 280, 270 and 255 mEq / kg) had higher (p <0.05) GP depending on vitamin D3 supplementation. In phase (1 to 21) days using high BEL significantly (p < 0.05) on feed intake and weight gain of the birds in comparison with chickens that received normal diets BEL. Likewise the different RVSP in isolation did not affect (p> 0.05) the performance characteristics evaluated in the same period. The period (1 to 35) days there was no interaction (p> 0.05) for the factors to study performance characteristics. However characteristics of GP and CR were significantly influenced (p <0.05) by using different programs BEL. Results showed that birds fed normal BEL had the highest GP also due to a higher CR in the period. Results of CA birds were not affected significantly (p> 0.05) by different dietary programs BEL, either, for different PSVD alone. Results of performance characteristics (CR, vii GP and CA) of the accumulated phase (1 to 41) days showed no interaction (p> 0.05) between the factors studied. Birds subjected to normal BEL obtained (p <0.05) higher feed intake and consequently a greater weight gain compared to the birds supplemented with high dietary BEL in certain period. Interaction was observed (p <0.05) between the factors studied for feasibility of creation. The feasibility of creating a period of (1 to 41) when used the high BEL demonstrated a significant reduction (p <0.05) for the group of birds where no additional vitamin D supplementation. The results of standard VC BEL showed in their results were not affected (p > 0.05) by different sources of additional vitamin D supplementation during this period. Birds fed the normal 28 days BEL had higher (p <0.05) MS content of the bed compared to the high BEL. The calcium content in plasma increased (P <0.05) using the high BEL. The electrolyte balance influenced the nonfat dry tibia weight and Seedor index at 21 days, with birds subjected to greater BEL had lower weight and lower tibia Seedor index. And in the statistical analysis of weight and tibia ash showed significant effects for different programs BEL in the diets (P <0.05). Following the standard weight of bone and Seedor index, the ash weight of tibia were higher in birds from BEL normal to those fed higher and lower dosages of potassium and chlorine (high BEL), respectively. The results of the plasma calcium level of significance (P <0.05), indicating increased plasma calcium concentration due to the use of diets with high BEL. The serum phosphorus was not influenced by electrolyte balance so little by supplementation of vitamin D. The data in studies demonstrated that the program generated heavier birds and greater weight of ash into the tibia, as well as higher Seedor index that is associated with bone density.