본 연구는 개 동결 정액 융해 시 straw 크기 및 융해 속도가 융해 정자의 질(quality)에 미치는 영향을 조사하고 최적의 융해 조건을 조사하는데 그 목적이 있다. 정상적인 번식능을 가진 비글 수컷 5마리에서 정액을 채취하여 원심 분리하여 정장을 버리고 남은 정자에 동결보호제인 glycerol이 첨가된 tris-glucose-egg yolk extender를 첨가하여 동결하고 액체질소에 보관한 후 융해하였다. 동결 융해 조건에 따른 효과를 알아보

This study was conducted to evaluate effects of chopped and non-chopped rice straw on characteristics of silage-basedtotal mixed ration (TMR) according to the particle size, laceration, and in situ dry matter (DM) degradation. The threerice straw silages as low moisture unchopped (LMUC; 32.75% of moisture, unchopped), high moisture unchopped(HMUC; 42.05% of moisture, unchopped), and high moisture chopped (HMC; 44.71% of moisture, chopped to 30cmlengths) were tested. Samples were collected at every 5 minutes from 10 min of pre-mixing to 50 min. The percentageof >19mm in LMUC and HMC was decreased to 7.23% and 7.74% (p<0.05), respectively, and the percentage of 8mm>was increased to 5.81% and 5.24%, respectively. Furthermore, the laceration of forage by a TMR mixer showed that therewas little change in the reduction of 1.26% in HMC, but was reduced to 7.53% and 16.06% in LMUC and HMUC,respectively. The peNDF>8 was maintained 17~18.5% of the optimal requirement level for 15 to 45 min mixing in LMUCand for 30 to 50 min mixing in HMC, but it exceeded the level of peNDF>8 in the range of 21.49 to 22.53% for 50minmixing in HMUC. However, ruminal in situ DM degradation appeared as LMUC>HMUC>HMC. Therefore, theseresults suggest that the rice straw silage may be useful for high-yielding lactating cows, if it can be supplied with theadequate peNDF, and the limiting factor on DMI and DM degradation was reduced by crushing of the plant tissue, althoughthe rice straw silage was concerned to low quality forage.