Chemical and physical properties of organic bedding materials

Authors: Spiehs, Mindy; Woodbury, Bryan; BROWN-BRANDL, TAMI - University Of Nebraska

Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/13/2023
Publication Date: 10/31/2023
Citation: Spiehs, M.J., Woodbury, B.L., Brown-Brandl, T.M. 2023. Chemical and physical properties of organic bedding materials. Applied Engineering in Agriculture. 39(6):595-604. https://doi.org/10.13031/aea.15673.
DOI: https://doi.org/10.13031/aea.15673

Interpretive Summary: Producers have been bedding livestock and poultry for centuries with locally available crop- and wood-based bedding materials. The choice of bedding material can affect animal health and behavior, pen and animal cleanliness, and air quality in the facility, which are determined by the physical properties of the bedding materials. Typically, bedding materials are selected based only on availability of supply and cost, without consideration for other factors. This may be due to a lack of understanding regarding how these factors influence profitability or simply a lack of information available about the physical properties of a particular bedding material. A study was conducted to determine the amount of water that bedding could absorb (water holding capacity) and how quickly the bedding would release the water into the atmosphere (rate of evaporative water loss). Corn stover, soybean stover, wheat straw, switch grass, paper, corn cobs, pine, dry cedar, and green cedar were evaluated; each bedding material was evaluated at a coarse, medium, and finely ground particle size. Finely ground particles of all bedding materials absorbed more water than medium or coarse ground particles. Corn stover and wheat straw had the highest water holding capacity, while switch grass, dry cedar, green cedar, and corn cobs absorbed the least amount of water. Corn cobs retained water the longest. This information helps producers make informed decisions about absorption capacity of available bedding materials. Producers seeking a bedding material that has a high water holding capacity, does not become saturated immediately and can release water back into the atmosphere at a moderate rate may find corn stover or wheat straw to have these desirable characteristics. Pine chips and soybean stover may also be a good option based on the high water holding capacity.

Technical Abstract: Physical and chemical characteristics of organic bedding materials determine how well they will absorb and retain moisture and may influence the environment in livestock facilities where bedding is used. The objective of this study was to determine water holding capacity (WHC) and rate of evaporative water loss (EWL) of organic materials used as bedding in livestock facilities. Corn stover, soybean stover, wheat straw, switch grass, paper, corn cobs, and wood (pine and cedar) were evaluated; coarse, medium, and fine particle sizes of each bedding material were measured. The WHC was determined by submerging bedding materials in permeable nylon bags for 1, 3, 5, 10, 20, and 30 min, and 1, 3, 6, 9, 12, 24, 48, and 72 hours. Generally, finely ground particles had higher WHC (P < 0.05) than the medium or coarsely ground particles of the same material. Corn stover (3.2 g g-1) and wheat straw (3.3 g g-1) had the highest WHC. Switch grass, dry cedar, green cedar, and corn cobs (1.4, 1.5, 1.6 and 1.9 g g-1, respectively) absorbed the least amount of water. Corn cobs retained water the longest when EWL was measured at 100, 25, and 15°C (6.0, 33.0, and 38.1 days, respectively).