EVALUATION OF THE EFFECT OF SODIUM BUTYRATE ADDITION TO BROILER DIETS ON ENERGY AND PROTEIN DIGESTIBILITY, PRODUCTIVE PARAMETERS AND SIZE OF INTESTINAL VILLI OF ANIMALS

摘要

A total of 750 Cobb 400 one day old broiler chickens were used to evaluate the influence of sodium butyrate has on the animal performance, energy and protein digestibility of the diet and villi development. The animals followed a 3 phase feeding program with mash diets: starter, from 1 to 11 days (52% corn, 40% soya and 3% palm oil; EM 2950 kcal, 23% protein and 1.38% lysine), grower from 12 to 21 days (56% corn, 35% soya and 4% palm oil; EM 3050 kcal, 21 % protein and 1.26% lysine) and finisher from22 to 42 days (60% corn, 30% soya and 5% palm oil; 3150 kcal ME, 19% protein and 1.14% lysine). The trial evaluated 3 treatments: control treatment (no additives), treatment BUT 0.5 (0.5 kg/t of 92% sodium butyrate) and treatment BUT 1 (1 kg/t of 92% sodium butyrate). Each treatment was replicated 10 times and each replicate consisted of 25 animals at the start of the test. The animals' weight and feed intake were controlled every two weeks (change of phase). In addition, dietary energy and protein digestibility was evaluated from day 40 to day 42, by the total collection of excreta (and control of ingestion) methodology; on days 21 and 42, ileum samples were taken from a healthy animal from every replica to assess the length and width of intestinal villi. There were no statistically significant differences in the zootechnical parameters: at the end of the trial, the average daily gains were 47.7 g/day for control, 48.0 g/day for BUT 0.5 and 48.6 g/day for BUT 1 (P 0.47), average daily feed intake was 81.7 g/day for control, 81.6 g/day for BUT 0.5 and 83.6 g/ day for BUT 1 (P 0.56) and feed conversion ratios were 1.71 for control, 1.72 for BUT 0.5 and 1.72 for BUT 1 (P 0.91). However, the digestibility of protein and energy were influenced by the addition of butyrate in the diet: The digestible energy for the growth diet in the control treatment was 3105 kcal, for BUT 0.5 it was 3264 kcal and 3285 kcal for BUT 1 (P <0.001); the digestibility of the protein was 64.69 % in the control diet, 65.81 % in the BUT 0.5 and 67.70 % in the BUT 1 grower diet (P <0.001). The lengths and widths of the villis were also affected by the addition of butyrate in the diet and at day 21, the lengths were 0.977, 1.516 and 1.243 mm for control, BUT 0.5 and BUT 1 respectively (P <0.001), and the widths 224.7, 260.8 and 197.7 microns (P 0.1370); at day 42, the lengths were 0.944,1.314 and 1.116 mm for control, BUT 0.5 and BUT 1 (P 0.068), and the widths were 138.5, 314.2 and 317.2 microns respectively (P <0.001). It isconcluded that inclusion of butyrate in the diet improves the digestibility of energy and protein by increasing intestinal absorption surface.