Exp. II. The evaluation of bedding materials by types and the species of pine trees for Hanwoo cattle

For Exp. II, the same bedding materials as used in Exp. I were prepared except RH. The RH treatment was excluded in Exp. II, because of relatively low quality of physicochemical characteristics.

For Exp. II, SD, WS, and S+W originating from Russia and New Zealand were prepared. Thirty six Hanwoo cows were allocated to each of three types of bedding materials, and an experimental period was 21 days and performed duplicated (6 weeks; October to November). Triplicated pens were allocated to one of three bedding materials, thus total 9 pens were used in this study. The cows were housed in pens (4 cows/pen; 4.0 m wide× 8.2 m length = 32.8 m²/pen; 8.2 m² for each cow) with one side a 4.0 m wide feed bunk side (side A) and another side equipped with water supply (side B). There was a shallow divider (15 cm height×20 cm wide) made of concrete between A and B.

Offered feeds in this study were total mixed ration and the chemical composition of the diet is described in Table 1. Cows were offered feeds 5 kg equally at 06:00 and 17:00 h on daily basis (10 kg/d for each cow, as fed basis), and allowed to access fresh water and mineral block without any restriction during the whole experimental period. Blowing fans (diameter = 1,025 mm, 790 rpm; DVN-1007, Dongkun Industrial Co., Ltd, Incheon, South Korea) were installed and operated at 2 m/s (measured by digital anemometer; AR-836, Smart Sensor, Guangdong, China) in every two pen for maximizing the usability of bedding materials.

Chemical composition of experimental diet

DM, dry matter; CP, crude protein; EE, ether extract; CF, crude fiber; NDF, neutral detergent fiber; ADF, acid detergent fiber; Ca, calcium; P, phosphorus.

In Exp. II, beddings samples were collected every week at 10:00 AM from 12 sampling spots per pen by grab sampling to avoid sampling bias. Obtained bedding samples were transported immediately to the laboratory for measuring moisture concentrations by a forced-air dry oven (SJ201D, Sejong Scientific Co., Seoul, South Korea; 105°C; overnight, more than 12 h). Ammonia concentrations and pH in these samples were not measured because these beddings were not good indicators of changes in the ammonia situation at farms (Ahn et al., 2015).

Data obtained from the evaluation of bedding materials for Hanwoo cattle were subjected to statistical analysis using the GLM procedure of SAS (SAS Institute, 2002; version 9.03). Data were analyzed by variance analysis and Duncan’s multiple range tests were used to determine significant differences (p<0.01 and 0.05) among bedding materials within each treatment.