• Asian-Australasian Journal of Animal Sciences
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• 제28권10호
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• pp.1454-1464
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• 2015

Four methods were adopted, including the mobile nylon bag (MNB) method, modified three-step in vitro (MTS) method, original three-step in vitro (OTS) method, and acid detergent insoluble nitrogen (ADIN) estimating method, to evaluate the intestinal digestibility of rumen undegradable protein (DRUP) of 10 types of concentrates and 7 types of roughages. After correlation analysis to determine the DRUP values using the MNB, MTS, OTS, and ADIN methods, the study aimed to find out appropriate methods to replace the MNB method due to its disadvantages such as high price, long time period, and use of a duodenal T-fistula. Three dairy cows with a permanent ruminal fistula and duodenal T-fistula were used in a single-factor experimental design. The results showed that the determined DRUP values using the MNB method for soybean meal, cottonseed meal, rapeseed meal, sunflower meal, corn germ meal, corn, rice bran, barley, wheat bran, corn fiber feed, Alfalfa (Zhao dong), Alfalfa (Long mu 801), Alfalfa (Long mu 803), grass (North), Grass (Inner Mongolia), corn silage and corn straw were 98.13%, 87.37%, 88.47%, 82.60%, 75.40%, 93.23%, 69.27%, 91.27%, 72.37%, 79.03%, 66.72%, 68.64%, 73.57%, 50.47%, 51.52%, 54.05%, and 43.84%, respectively. The coefficient of determination ($R^2=0.964$) of the results between the MTS method and the MNB method was higher than that ($R^2=0.942$) between the OTS method and the MNB method. The coefficient of determination of the DRUP values of the concentrates among the in vitro method (including the MTS and OTS methods) and the MNB method was higher than that of the roughage. There was a weak correlation between the determined DRUP values in concentrates obtained from the ADIN method and those from the MNB method, and there was a significant correlation (p<0.01) between the determined DRUP values of the roughage obtained from the MNB method and those obtained from ADIN method. The DRUP values were significantly correlated with the nutritional ingredients of the feeds. The regression equation was DRUP =100.5566+0.4169CP - 0.4344SP - 0.7102NDF - 0.7950EE ($R^2=0.8668$, p<0.01; CP, crude protein; SP, soluble protein; NDF, neutral detergent fiber; EE, ether extract). It was concluded that both the MTS method and the OTS may suitable to replace the MNB method for determining the DRUP values and the former method was more effective. Only the ADIN method could be used to predict the values of the roughages but conventional nutritional ingredients were available for all of the samples' DRUP.

• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.215-222
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• 1997

Ten rice varieties were planted at two locations (lowland and highland), during the wet and dry seasons of different years. In vivo digestibility and voluntary intake of the straw, were determined in groups of fat-tail sheep, supplemented with $18g{\cdot}kg^{-0.75}$ concentrate DM, containing ~20% crude protein. Voluntary intake of digestible straw organic matter (DOMI) consistently varied from 15.2 to $20.9g{\cdot}kg^{-0.75}$ between straw varieties, averaged over locations, years and seasons, despite considerable variation between individual batches. This variation in the nutritive value of the straw was independent of straw and grain yield, so it would seem that there is scope for selection of rice varieties with straw of higher nutritive value. The variation in DOMI of straw among location of growth, year and season, was of a magnitude similar to the improvement brought about by urea-ammoniation. The in sacco degradation characteristics and digestibility of rice straw residues were superior to those of the offered straw. This can be attributed to a preference for rice straw leaves relative to stems. Averaged over location of growth, year and season, characteristics of in sacco degradation, i.e. the rate of fermentative degradation and the truly undegradable fraction, emerged as accurate predictors of the nutritive value of rice straw.

• Asian-Australasian Journal of Animal Sciences
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• 제25권11호
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• pp.1559-1567
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• 2012

The objective of this study was to evaluate ruminal degradability and intestinal digestibility of crude protein (CP) and amino acids (AA) in hempseed cake (HC) that were moist heat treated at different temperatures. Samples of cold-pressed HC were autoclaved for 30 min at 110, 120 or $130^{\circ}C$, and a sample of untreated HC was used as the control. Ruminal degradability of CP was estimated, using the in situ Dacron bag technique; intestinal CP digestibility was estimated for the 16 h in situ residue using a three-step in vitro procedure. AA content was determined for the HC samples (heat treated and untreated) of the intact feed, the 16 h in situ residue and the residue after the three-step procedure. There was a linear increase in RUP (p = 0.001) and intestinal digestibility of RUP (p = 0.003) with increasing temperature during heat treatment. The $130^{\circ}C$ treatment increased RUP from 259 to 629 g/kg CP, while intestinal digestibility increased from 176 to 730 g/kg RUP, compared to the control. Hence, the intestinal available dietary CP increased more than eight times. Increasing temperatures during heat treatment resulted in linear decreases in ruminal degradability of total AA (p = 0.006) and individual AA (p<0.05) and an increase in intestinal digestibility that could be explained both by a linear and a quadratic model for total AA and most individual AA (p<0.05). The $130^{\circ}C$ treatment decreased ruminal degradability of total AA from 837 to 471 g/kg, while intestinal digestibility increased from 267 to 813 g/kg of rumen undegradable AA, compared with the control. There were differences between ruminal AA degradability and between intestinal AA digestibility within all individual HC treatments (p<0.001). It is concluded that moist heat treatment at $130^{\circ}C$ did not overprotect the CP of HC and could be used to shift the site of CP and AA digestion from the rumen to the small intestine. This may increase the value of HC as a protein supplement for ruminants.

• Journal of Animal Science and Technology
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• 제44권1호
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• pp.105-112
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• 2002

동물성 부산물 사료(우모분, 우지박, 내장분)단백질의 반추위내 분해특성과 하부장기내 이용성에 대한 열처리 효과를 구명하기 위하여 반추위와 십이지장에 누관이 장착된 Holstein 건유우 3두를 공시하였다. 시험사료에 대한 열처리는 149$^{\circ}C$가 유지되는 oven에서 4시간동안 처리한 후, 1 mm체를 통과시켰다. 시험사료의 반추위내 분해특성은 발효시간별 분해율에서 비선형회귀식을 유도하여 구하였고, 사료단백질의 하부장기내 이용성은 mobile nylon bag기법으로 추정되었다. 농후사료와 orchard grass를 60:40의 비율로 급여하였으며, 물과 mineral block은 자유섭취토록 하였다. 조단백질의 반추위내 유효분해도(k=0.05) 및 하부장기내 소실율에 있어서 우모분은 각각 30.2% 및 56.2%, 우지박은 75.0% 및 18.6% 그리고 내장분은 56.4% 및 37.9%였다. 시험사료에 대한 열처리효과에 있어서 조단백질의 반추위내 유효분해도는 우모분과 내장분은 증가하였으나 우지박은 감소되었고(P$<$0.05), 하부장기내 조단백질 소실율에서는 우지박은 증가된 반면, 우모분과 내장분은 감소되어(P$<$0.05) 상반되는 결과를 나타내었다. 반추위 미분해 사료단백질의 하부장기내 이용율은 우모분, 우지박 및 내장분에 대해서 각각 80.4%, 83.8% 및 86.9%였으며, 열처리를 함으로써 우모분과 우지박은 각각 94.0% 및 91.3%로 향상되었으나, 내장분은 76.5%로 낮아졌다(P$<$0.05).