초록
From the same harvest of Italian ryegrass (Lolium multiflorum, Lam.), hay(H), wilted silage(WS), pressed cake hay (PCH) and pressed cake silage (PCS) were prepared. These four preserved roughages were restrictedly fed to four goats attached with rumen fistula by $4{\times}4$ Latin square design to determine the effect of different physical and chemical properties of the roughages on the ruminal acid concentrations. Each goat was given a diet at 2% of the body weight daily in dry matter basis by separating into two equal portions. Half was given at 9 AM and the other half at 5 PM. Ruminal pH was reduced to around 5.5 within 30 minutes after feeding PCS and it was recovered above 6 in 1-2 hours after feeding. By feeding WS, ruminal pH was also reduced but never fell below 6. The two hays rather increased ruminal pH after feeding. The reduction of ruminal pH in the silage feedings was due to the high lactic acid content of the silages, because the highest ruminal lactic acid concentration was observed 30 minutes after feeding when the lowest ruminal pH was attained. While the ruminal VFA concentrations became the highest 1-2 hours after feeding. The ruminal acetic acid concentration fluctuated so much that no significant tendency was observed among the four dietary treatments. The ruminal propionic acid concentration was higher in feeding silages reflecting the initial high lactic acid concentration. As the result, acetic/propionic acid ratio was lower in the silage feedings than in hay feedings. Higher ruminal butyric acid concentration was observed in WS than in others.