The objective of this study was to determine the effect of various roughage sources on nutrient digestibility and enteric methane (CH4), and carbon dioxide (CO2) production in goats. Four castrated black goats (48.5 ± 0.6 kg) were individually housed in environmentally controlled respiration-metabolism chambers. The experiment design was a 4 × 4 balanced Latin square design with 4 roughage types and 4 periods. Alfalfa, tall fescue, rice straw, and corn silage was used as representative of legume, grass, straw, and silage, respectively. Dry matter digestibility was higher (p < 0.001) in corn silage than in alfalfa hay. Dry matter digestibility of alfalfa hay was higher than those of tall fescue or rice straw (p < 0.001). Neutral detergent fiber digestibility of tall fescue was lower (p < 0.001) than those of alfalfa, rice straw, or corn silage. Daily enteric CH4 production and the daily enteric CH4 production per kilogram of BW0.75, dry matter intake (DMI), organic matter intake (OMI), digested DMI, and digested OMI of rice straw did not differ from those of tall fescue but were higher (p < 0.001) than those of alfalfa or corn silage. Roughage type had no effect on enteric CO2 emission in goats. Straw appeared to generate more enteric CH4 production than legume or silage, but similar to grass.

Ⅰ. INTRODUCTION
 Ⅱ. MATERIALS AND METHODS
  1. Animals, diets, and experimental design
  2. Chemical analysis
  3. Gas production measurement
 Ⅲ. RESULTS AND DISCUSSION
 Ⅳ. CONCLUSION
 Ⅴ. ACKNOWLEDGEMENT
 Ⅵ. REFERENCES

• Youngjun Na(Department of Animal Science and Technology, Konkuk University, 건국대학교 동물자원과학과) | 나영준
• Seokjin Hwang(Department of Animal Science and Technology, Konkuk University, 건국대학교 동물자원과학과) | 황석진
• Yongjun Choi(Department of Animal Science and Technology, Konkuk University, 건국대학교 동물자원과학과) | 최용준
• Geetae Park(Department of Animal Science and Technology, Konkuk University, 건국대학교 동물자원과학과) | 박기태
• Sangrak Lee(Department of Animal Science and Technology, Konkuk University, 건국대학교 동물자원과학과) | 이상락 Corresponding author