|GALLOWAY SR, D|
Submitted to: Bioresource Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/26/1996
Publication Date: N/A
Interpretive Summary: Attributes of broiler litter such as low concentrations of available energy and rumen undegradable protein restrict dietary levels of inclusion and scenarios in which the byproduct can be used effectively. Therefore, objectives of this experiment were to determine effects of adding different types and levels of common carbonaceous feedstuffs to broiler litter before deep-stacking on nutrient composition and degradability for different lengths of incubation. Results of this experiment suggest that cereal grain addition alone to broiler litter before deep-stacking is of marginal or no interest to improve nutritive value of broiler litter because of limited change in nitrogen recovery and loss of neutral detergent soluble organic matter relative to broiler litter incubated alone; increased recovery of neutral detergent fiber; and decreased ruminal fiber degradability with long incubation (i.e., 9 wk). Forage sources added alone to broiler litter before deep-stacking may be of similar low utility as cereal grain inclusion, since recoveries of nitrogen and neutral detergent fiber were not markedly changed compared with broiler litter incubated alone. Conversely, relative to broiler litter incubated alone, molasses inclusion decreased neutral detergent fiber recovery, increased nitrogen and neutral detergent soluble organic matter recoveries and increased in situ ruminal degradability of dry matter, nitrogen and neutral detergent fiber. In general, effects of molasses when added alone varied with inclusion level and incubation length. Furthermore, desirable associative effects, such as in nitrogen and neutral detergent fiber recoveries, were observed when molasses was mixed with other carbonaceous feedstuffs.
Technical Abstract: Different types and levels of carbonaceous feedstuffs mixed with broiler litter were incubated in a broiler litter deep-stack for 3 or 9 wk to determine effects on nutrient composition, recovery and digestibility. Substrates were ground corn (C), whole corn, ground wheat, molasses (M), bermudagrass hay (B), wheat straw and 1:1 (dry matter) mixtures thereof (excluding whole corn and a B-wheat straw mixture) mixed at 10 or 20% of total dry matter with broiler litter. Nitrogen recovery was increased by singular addition of M; associative effects of mixing M with other carbonaceous feedstuffs occurred; and M effects varied with level of addition and length of incubation (112, 131, 114, 124 and 123% with 10% substrate, and 114, 146, 116, 134 and 135% with 20% substrate (SE 1.50); 113, 133, 114, 124 and 127% with 3-wk incubation, and 113, 144, 116, 134 and 131% with 9-wk incubation (SE 1.50) for C, M, B, C-M and M-B, respectively). Inclusion of M decreased neutral detergent fiber recovery more at 20 than 10% and at 9 vs 3 wk of incubation (106, 76, 84, 81 and 75% with 10% substrate, and 111, 68, 86, 75 and 70% with 20% substrate; 107, 82, 88, 82 and 80% with 3-wk incubation, and 110, 63, 83, 74 and 65% with 9-wk incubation (SE 2.13) for C, M, B, C-M and M-B, respectively). Molasses resulted in 48-h in situ ruminal neutral detergent fiber disappearance greater than expected based on disappearance of feedstuffs before deep-stacking (3 wk: 4, 15, 1 -1 and 4 (SE 0.88); 9 wk: -12, 3, -13, 1 and 0 with 10% substrate, and -10, 9, -11, 0 and 0 percentage unit difference with 20% substrate (SE 1.1) for C, M, B, C-M and M-B, respectively). In conclusion, M addition resulted in a number of changes suggesting improved nutritive value of broiler litter.