Síntese de proteína microbiana e perdas endógenas em ovinos alimentados com silagem de maracujá

Abstract

The main of goal to experiment was to evaluate the microbial protein synthesis and endogenous losses in sheep with no defined breed pattern, fed diets composed of passion fruit byproduct in substitution for the tífton hay. The work was carried out at the Agrarian Sciences Center of the Federal University of Alagoas, using 28 sheeps, with an average body weight of 25 kg. The experimental was of 60 days, being 30 for adaptation of the environment and management and 30 for gathering data. The diet had a high content of tífton hay (Cynodon ssp.) and passion fruit byproduct silage (Passiflora edulins), and as concentrate, soybean meal (Glycine max), maize meal (Zea mays) and mineral salt, supplied ad libitum. The treatments were constituted of different levels of the passion fruit byproduct in substitution of tífton hay (0, 20, 40 and 60%) in diets whose proportion was 60% of bulky and 40% of concentrate. The animals were housed in individual, identified stalls equipped with a feeder and drinking fountain. Weighed at the beginning and end of the experimental period. The collection of spot urine was performed four hours after feeding, at the beginning and at the end of the experiment. From urine collection, creatinine was analyzed to estimate urinary volume and purine derivatives (allantoin, uric acid, xanthine and hypoxanthine) to estimate the production of microbial protein. Endogenous losses were estimated by the NRC (2007) and AFRC (1993). A completely randomized design was used, with four treatments and seven replicates. The data were interpreted through analysis of variance and regression using the statistical program SAS (2001). The microbial protein synthesis showed an increasing linear effect, with a maximum value of 163.29 g / day for the 60% substitution level. Thus, it was concluded that the 60% substitution level presents a higher estimate of microbial protein synthesis and endogenous losses performed by NRC (2007) and AFRC (1993) in sheep.