Nutritive Value Variation of Paunch Manure as an Alternative Feed Ingredient

SIMPLE SUMMARY: Sustainable livestock production is a benchmark for advancements in animal nutrition. Recovery of nutrients from products currently disposed of provides a potential solution to this mandate. Paunch manure is a potential novel feed ingredient comprised of digested feedstuffs at different stages of degradation, saliva, microorganisms, and products of fermentation. Thus, our objective was to determine the variability in nutritive values of dried paunch manure collected from harvested cattle. Animal-to-animal variation accounted for 30% to 75% of the variance in all measures of nutritive value. We believe that dried paunch manure may be a viable feed ingredient for inclusion in livestock rations, but a centralized composting system may be necessary to increase consistency. ABSTRACT: Ruminants, which have multi-compartmented stomachs, are adapted to digest cellulosic materials, which constitute the primary expense on ranches and dairies. Industrial byproducts can be repurposed for livestock diets to decrease these costs. Therefore, finding alternative feedstuffs may benefit the economics of livestock production. The goal of this project was to evaluate the variation in nutritive value of ruminal waste as a potential feedstuff. Twelve paunch samples were collected from individual cattle across multiple harvest dates at the Tarleton State University Meat Laboratory, Stephenville, TX. Samples were dried and assayed for dry matter (DM), crude protein (CP), sequential neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL), and physically-effective fiber (peNDF). Samples were subjected to batch-culture in vitro digestibility assays for the determination of digestibility coefficients. Mean NDF, ADF, ADL, CP and peNDF concentrations were 681, 399, 109, 150, and 387 g kg(−1) DM, respectively. Contribution to variance from sample for NDF, ADF, ADL, CP, and peNDF were 75.3, 41.9, 33.0, 51.2, and 71.3%, respectively. In vitro true digestibility (IVTD) and in vitro NDF digestibility (IVNDFD) were recorded as 462 and 216 g kg(−1) DM, respectively. Contribution to variation of sample for IVTD and IVNDFD were 31.0 and 30.7%, respectively. Results indicate that rumen waste harvested from abattoirs may be useful for sustainable livestock production, while reducing environmental threats posed by disposal, but the viability of the product is highly dependent on the source animal. For full viability of application in a sustainable system, a centralized receiving and compositing system may be useful for developing a consistent product.