INTAKE AND DIGESTION BY HOLSTEIN STEERS CONSUMING DIFFERENT PARTICLE-SIZE FRACTIONS OF BROILER LITTER

Eight Holstein steers (153 +/- 13.6 kg body weight) were used in two s imultaneous 4 x 4 Latin squares with 21-day periods to determine effec ts of separating deep-stacked broiler litter into small and large part icle size fractions on feed intake and digestibility. Steers were fed diets with or without two sources of deep-stacked broiler litter (sour ce A: 24% crude protein and 35% neutral detergent fiber; source B: 23% crude protein and 44% neutral detergent fiber). All steers were fed g round corn at approximately 0.5% body weight (dry matter basis). Bermu dagrass hay was consumed ad libitum by Control steers (without broiler litter) or at 0.5% body weight (dry matter basis) for treatments with dietary broiler litter. Broiler litter was consumed ad libitum withou t separation (whole; W) or after separation (l-mm screen aperture) int o small(S; 27 and 33% crude protein for A and B, respectively) and lar ge (L; 22 and 18% crude protein for A and B. respectively) particle si ze fractions. Organic matter intake was increased (P = 0.06) by dietar y inclusion of broiler liner (4.55, 4.56, 4.63, 4.73, 4.24, 5.18, 4.74 and 4.59 kg day(-1) for Control-A, W-A, S-A, L-A, Control-B, W-B, S-B and L-B, respectively; SE 0.229). Total tract organic matter digestib ility was greater (P = 0.08) for broiler litter source A than for B (5 7.4, 57.8, 54.9, 57.6, 56.5, 48.4, 46.9 and 54.8%; SE 3.83), and diges tible organic matter intake tended (P = 0.11) to be greater for source A (2.56, 2.64, 2.54, 2.72, 2.36, 2.51, 2.16 and 2.58 kg day(-1) for C ontrol-A, W-A, S-A, L-A, Control-B, W-B, S-B and L-B, respectively; SE 0.166). in conclusion, separating deep-stacked broiler litter into tw o particle size fractions did not alter feeding value as assessed by d igestible organic matter intake by growing steers. (C) 1998 Elsevier S cience B.V.