ABSTRACT
This study aimed to determine the temperature and drying time through rotative rolls, that sugar cane yeast is subjected to in order to allow best energy utilization by laying hens and broilers. Three metabolism trials were conducted to determine the values of apparent metabolizable energy (AME) and apparent corrected for nitrogen balance (AMEn), coefficient of apparent metabolizable dry matter (CAMDM) and gross energy (CAMGE). The first experiment was conducted with laying hens (E1), the second with broilers (E2) in growth and the third with broilers at different ages (E3). In the experiments E1 and E2 the treatments consisted of a reference diet, based on corn and soybean meal, and five test diets containing 20% of the yeast to be tested. The evaluated yeasts were subjected to the following processes: Lev.A) drying at 107°C for 107 seconds; Lev.B) 95°C for 107'; Lev.C) 100ºC for 107'; Lev.D) 100°C for 93' and Lev.E) 100ºC for 123'. For the E3 group AME, AMEn, CAMDM and CAMGE were determined for the Lev.B of broilers with 1 to 8 days 14 to 22 days, and 28 to 36 days of age. In E1 there were no differences in AME, AMEn and CAMGE between yeasts, with mean of 1773kcal/kg 1733kcal/kg and 40.22%, respectively. However the CMMS was greater for Lev.D (50.36%). In E2, the AME (1633kcal/kg), AMEn (1382kcal/kg) and CAMGE (32.22%) were best for Lev.B, but there was no significant difference in the values of CAMMD (29 63%). TheE3 grouphad values of 2723kcal/kg; 1604kcal/kg and 1414kcal/kg of AME; 2366kcal/kg, 1391kcal/kg and 1303kcal/kg of AMEn; 52.43%, 36.74%, and 25.64% of CAMDM; and 54.37%, 33.49% and 24.96% of CAMGE, in the ages of 1 to 8 days, 14 to 22 days and 28 to 36 days, respectively. In conclusion, for layer hens, the yeast should be dried at 100°C for 93' or 107 seconds or 95ºC for 107' and for, broilers, it should be dried at 95°C for 107 seconds.
alternative food; digestibility; processing; Saccharomyces cerevisiae; energy value