Effects of two levels of quantitative feed restriction for a 7- or 14- days period on broilers blood parameters / Effects of two levels of quantitative feed restriction for a 7- or 14- days period on broilers blood parameters

ABSTRACT

Background: Compensatory growth after a feed restriction (FR) period, associated with increased feed intake and digestive adaptation allows the broilers chickens to demonstrate better food conversion efficiency and meat yield when submitted to an early-age food restriction. Differences in levels of feed restriction or on the period of feed restriction need to be adapted to each broilers strain, and should balance an adequate physiological response towards compensatory growth for production of the most suitable carcass, the smallest stress and an adequate immune-competence levels. So far, investigations showed considerable variations concerning broilers response to early life restrictions, physiological associate changes, compensatory growth and fat deposition. This experiment had been done to compare the effects of quantitative feed restriction imposed in different intensities and durations on the blood concentrations of energy, protein and lipid metabolites. Materials, Methods & Results: Five experimental treatments included T1 corresponded to controls (ad libitum); T2 and T4 groups were submitted to 25 and 50% feed restriction for one week; and T3 and T5 were feed deprived in 25 and 50% for two weeks, in three replicates of 10 pieces per treatment. Periods previous and subsequent (up to 42 days) to FR periods were fed ad libitum. All chickens were fed with ad libitum befo

RESUMO

Background: Compensatory growth after a feed restriction (FR) period, associated with increased feed intake and digestive adaptation allows the broilers chickens to demonstrate better food conversion efficiency and meat yield when submitted to an early-age food restriction. Differences in levels of feed restriction or on the period of feed restriction need to be adapted to each broilers strain, and should balance an adequate physiological response towards compensatory growth for production of the most suitable carcass, the smallest stress and an adequate immune-competence levels. So far, investigations showed considerable variations concerning broilers response to early life restrictions, physiological associate changes, compensatory growth and fat deposition. This experiment had been done to compare the effects of quantitative feed restriction imposed in different intensities and durations on the blood concentrations of energy, protein and lipid metabolites. Materials, Methods & Results: Five experimental treatments included T1 corresponded to controls (ad libitum); T2 and T4 groups were submitted to 25 and 50% feed restriction for one week; and T3 and T5 were feed deprived in 25 and 50% for two weeks, in three replicates of 10 pieces per treatment. Periods previous and subsequent (up to 42 days) to FR periods were fed ad libitum. All chickens were fed with ad libitum befo