BEDDING OPTIONS FOR AN ALTERNATIVE HOUSING SYSTEM FOR DAIRY COWS: A DESCRIPTIVE STUDY

Availability of bedding material for compost bedded pack barns is a concern for dairy producers who use this type of alternative housing system. The material most commonly used in these barns is thy sawdust. The objective of this descriptive study was to evaluate different types of bedding material that could potentially substitute or partially substitute for sawdust in these housing systems. The study was conducted at the West Central Research & Outreach Center in Morris, Minnesota, from November 2006 to March 2007. Materials included: pine sawdust (control) (SD), corn cobs (CC), pine woodchip fines (WC), and soybean straw (SS). Some of these materials were evaluated as mixtures on a 2:1 volume-to-volume ratio. These mixtures included: woodchips/sawdust (WC/SD), woodchips/soybean straw (WC/SS), and soybean straw/sawdust (SS/SD). Experimental bedded packs were used, each with one of the bedding materials, and 16 cows were placed on each pack. Replicated samples of the bedded pack material were collected twice a month and analyzed for dry, matter C:N ratios and pH were analyzed monthly Temperatures of each pack were measured weekly at various depths (15.2, 30.5, 45.7, and 61.0 cm). Cows were scored for hygiene (1=clean, 5=dirty) twice a month. Moisture content of SD was 59.7; CC, 44.5; WC/SD, 60.6; SS/SD, 58.2; WC/SS, 60.7; and SS 60.6. SD pH was 8.7; CC, 7.7; WC/SD, 8.6; SS/SD, 8.6; WC/SS, 8.3; and SS, 8.6. C:N ratio of SD was 37.3; CC, 29.2; WC/SD, 47.5; SS/SD, 25.6; WC/SS 31.0; and SS, 22.8. Hygiene score of cows on SD was 2.4; CC, 2.7; WC/SD, 2.5; SS/SD, 2.9; WC/SS, 2.6; and SS, 2.8. Based on these results and our observations, it appears that any of the bedding materials evaluated in this study would work in this type of housing system if proper bedding management is applied on a consistent basis. it was concluded that ideal bedding material for compost barns should be thy, processed to less than 2.5 cm long, offer structural integrity, and have good water absorption and holding capacity.