Metodologia de uso de níveis crescentes de substituição em ensaios de digestibilidade na avaliação de alimento fibroso para suínos

Abstract

Two experiments were carried out to study the methodology of using increasing levels of substitution of the basal diet by fibrous feedstuffs test, (sticky coffee hull - SCH) in the digestibility trials with pigs during the growing-finishing phase. In the Experiment I, it was conducted a digestibility trial using 15 crossbred barrows, with 72.48 ± 7.16 kg initial body weight, distributed in a randomized block design. In general, the use of increasing levels of substitution (7, 14, 21 or 28%) reduced the SCH digestibility. The metabolizable energy (ME) values as fed basis were 2456, 2377, 2247 and 1945 Kcal / kg. In the Experiment II, there were used 42 pigs of initial body weight of 30.27 ± 1.95 kg in the growing phase and 42 pigs with initial body weight of 60.02 ± 4.10 kg in the finishing phase, allotted in a completely randomized design, with six treatments and seven replicates with one animal per experimental unit. The treatments consisted of a control diet, four diets with levels of ME obtained in Experiment I plus a diet with ME estimated by linear regression equation for 15% of substitution. In the growth phase there was no effect of treatments on daily feed intake, daily weight gain (DWG) and feed:gain ratio. The economic feasibility study indicated that there was no difference in the cost of different diets. For finishing phase, the DWG was lower for levels 21 and 28%. The results indicate that higher levels of substitution overestimate the energy value and the method of increasing levels of substitution of the basal diet by feedstuffs test can be used to estimate the energy values of fibrous feedstuffs for pigs.