• Journal of Animal Science and Technology
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• 제48권4호
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• pp.541-554
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• 2006

제 3위 소화액 채취기법은 기존 반추위 영양생리 대사 패턴 측정방법인 in vivo, in vitro 및 in situ 방법의 단점을 극복하고 정확한 반추위 생리대사 패턴의 측정을 할 수 있는 기회를 가진다. 이 제 3위 소화액 채취기법을 이용한 측정방법은 기존의 post-ruminal sampling 기법과 비교해서 다음과 같은 장점들이 존재한다. 1) 단지 반추위캐뉼라가 설치된 동물만이 필요하며, 2) 제 3위 소화액에는 비교적 적은 내인성 질소가 존재하며, 3) 제 3위 소화액은 제 4위에서 시작되는 소화효소에 의한 소화를 피할 수 있는 점 등이다. 제 3위 소화액 내 반추위 미분해 용해성 질소화합물(SNAN)의 측정은 in situ 방법의 전제조건인 반추위에서 rapidly degradable N은 무한정 분해되며 따라서 비용해성 사료 N 만이 반추위를 벗어난다는 것이 오류임을 보여준다. 제 3위 소화액 내 SNAN 중 유리아미노산 및 용해성 단백질과 비교해서 양적으로 가장 많은 peptide는 반추위 단백질대사에서 peptide에서 아미노산으로의 분해과정이 분해율 제한요인이 될 수 있음을 시사한다.

• Journal of Animal Science and Technology
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• 제49권3호
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• pp.341-350
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• 2007

본 연구는 목초 사일리지를 기초사료로 급여한 젖소에 있어서 보리와 유채박 급여가 제 3위 소화액 내 soluble non-ammonia nitrogen fractions(SNAN fractions; 아미노산, 펩티드, 용해성 단백질 및 total SNAN)의 flow 패턴변화를 측정하기 위하여 실시하였다. 반추위 캐뉼라가 장착된 4마리 젖소는 4×4 라틴방각법에 의해 기초사료로 grass-red clover silage를 자유급여하여 사일리지 단독급여구(GS), 기초사료 + 보리6.0kg/d 급여구, 기초사료 + 유채박2.1kg/d 급여구 및 기초사료 + 보리6.0kg/d + 유채박2.1kg/d 급여구로 배치하였다. 제 3위 소화액은 제 3위 소화액 채취기구를 이용하여 사료급여 후 1.5h 간격으로 채취하였고, 그 소화액 내 SNAN fractions 정량은 ninhydrin assay를 이용하여 분석하였다. 보충사료 급여는 GS구에 비해 비록 통계학적 유의성은 없었지만 total SNAN flow를 증가시켰다. 제 3위 소화액 내 펩티드 flow 패턴은 12시간 feeding cycle 내내 SNAN fractions 중 양적으로 가장 높았으며, GS구에 비해 보충사료급여구에서 높은 펩티드 flow 패턴을 보였다. GS구를 제외한 보충사료처리구간에는 SNAN fractions flow 패턴 차이가 없었다. 15N을 이용하여 분석된 사료유래 SNAN fractions flow 패턴에서는 보충사료급여구가 GS구에 비해 높게 나타났다. 이상의 결과 제 3위로 유입되는 펩티드 flow는 전체 SNAN flow 중 양적으로 가장 중요한 N 이며, 보충사료 급여 시 그 펩티드 flow의 증가 가능성을 시사한다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1269-1275
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• 2012

An experiment was conducted to study the effect of soluble protein supplements on concentration of soluble non-ammonia nitrogen (SNAN) in the liquid phase of ruminal (RD) and omasal digesta (OD) of Korean native steers, and to investigate diurnal pattern in SNAN concentration in RD and OD. Three ruminally cannulated Korean native steers in a $3{\times}3$ Latin square design consumed a basal diet of rice straw and corn-based concentrate (control), and that supplemented (kg/d DM basis) with intact casein (0.24; IC) or acid hydrolyzed casein (0.46; AHC). Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 2.0 h intervals after a morning feeding. The SNAN fractions (free amino acid (AA), peptide and soluble protein) in RD and OD were assessed using the ninhydrin assay. Concentrations of free AA and total SNAN in RD were significantly (p<0.05) lower than those in OD. Although free AA concentration was relatively high, mean peptide was quantitatively the most important fraction of total SNAN in both RD and OD, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis of Korean native steers. Diurnal variation in peptide concentration in OD for the soluble protein supplemented diets during the feeding cycle peaked 2 h post-feeding and decreased thereafter whereas that for the control was relatively constant during the entire feeding cycle. Diurnal variation in peptide concentration was rather similar between RD and OD.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1460-1468
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• 2003

An experiment was conducted to quantify the flow of soluble non-ammonia nitrogen (SNAN) in the liquid phase of ruminal (RD) and omasal digesta (OD), and to investigate diurnal pattern in SNAN flow in OD. Five ruminally cannulated Finnish-Ayrshire dairy cows in a $5{\times}5$ Latin square design consumed a basal diet of grass silage and barley grain, and that supplemented with four protein feeds (kg/d DM basis) as follows: skimmed milk powder (2.1), wet distiller' solubles (3.0), untreated rapeseed meal (2.1) and treated rapeseed meal (2.1). Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 1.0 h interval during a 12 h feeding cycle. Both RD and OD were acidified, centrifuged to remove microbes and precipitated with trichloroacetic acid followed by centrifugation. The SNAN fractions (free amino acid (AA), peptide and soluble protein) in RD and OD were assessed using ninhydrin assay. Free AA, peptide and soluble protein averaged 60.0, 89.4 and 2.1 g/d, respectively, for RD, and 81.8, 121.5 and 2.5 g/d, respectively, for OD. Although free AA flow was relatively high, mean peptide flow was quantitatively the most important fraction of SNAN, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis. Diurnal pattern in flow of peptide including free AA in OD during a 12 h feeding cycle peaked 1 h post-feeding, decreased by 3 h post-feeding and was relatively constant thereafter. Protein supplementation showed higher flow of peptide including free AA immediately after feeding compared with no supplemented diet. There were no differences among protein supplements in diurnal pattern in flow of peptide including free AA in OD.

• Asian-Australasian Journal of Animal Sciences
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• 제5권1호
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• pp.13-18
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• 1992

Three cattle, a sheep and a goat were slaughtered to determine the distribution of digesta particles and mean size of digesta particles. Aliquot samples of digesta in the diverse sites of the digestive tracts were fractionated by a wet sieving technique. Fractionated particles were analyzed by the magnetic grid analyzer system constructed by authors. Results showed that the proportion of particles in digesta was similar among the omasum, abomasums cecum, colon and rectum, but that for the reticulo-ruminal digesta was different from the others. The pattern of the mass base frequency distribution of particles was also similar in the post-ruminal digesta. Average Heywood's diameter (the diameter equivalent to that of a circle with equal area to a projected area of a given particle) was about 1.2 mm in the reticulo-ruminal digesta and decreased to 0.65 mm for cattle or to about 0.35 mm for sheep and goat in the omasal digesta. Average Heywood's diameter was about the same in the post-ruminal digesta. It is concluded that mean particle size and particle distribution in digesta of the rectum or feces reflect those in digesta of the omasum.

• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1267-1278
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• 2009

Three beef steers fitted with permanent cannulae in the rumen and duodenum were used to determine the effects of protein supply from soyhulls (SH) and wheat bran (WB) on ruminal metabolism, blood metabolites, nitrogen metabolism, nutrient digestion and concentrations of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). In a 3${\times}$3 Latin square design, steers were offered rice straw and concentrates formulated either without (control) or with two brans to increase crude protein (CP) level (9 vs. 11% dietary DM for control and bran-based diets, respectively). The brans used were SH and WB that had similar CP contents but different ruminal CP degradability (52 vs. 80% CP for SH and WB, respectively) for evaluating the effects of protein degradability. Ruminal ammonia concentrations were higher for bran diets (p<0.01) than for the control, and for WB (p<0.001) compared to the SH diet. Similarly, microbial nitrogen and blood urea nitrogen were significantly increased (p<0.05) by bran and WB diets, respectively. Retained nitrogen tended (p<0.082) to be increased by SH compared with the WB diet. Intestinal and total tract CP digestion was enhanced by bran diets. In addition, bran diets tended (p<0.085) to increase intestinal starch digestion. Concentrations of SNAN fractions in RD and OD were higher (p<0.05) for bran diets than for the control, and for WB than for the SH diet. More rumendegraded protein supply resulting from a higher level and degradability of CP released from SH and WB enhanced ruminal microbial nitrogen synthesis and ruminal protein degradation. Thus, free amino acids, peptides and soluble proteins from microbial cells as well as degraded dietary protein may have contributed to increased SNAN concentrations in the rumen and, consequently, the omasum. These results indicate that protein supply from SH and WB, having a low level of protein (13 and 16%, respectively), could affect ruminal metabolism and nutrient digestion if inclusion level is relatively high (>20%).

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.392-403
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• 2008

Four ruminally fistulated Hanwoo steers were used to determine the effects of level and degradability of dietary protein on ruminal fermentation, blood metabolites and concentration of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). Experiments were conducted in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of treatments. Factors were protein supplements with two ruminal crude protein (CP) degradabilities, corn gluten meal (CGM) that was low in degradability (rumen-degraded protein (RDP), 23.4% CP) or soybean meal (SBM) that was high in degradability (RDP, 62.1% CP), and two feeding levels of CP (12.2 or 15.9% dry matter). Ruminal fermentation rates and plasma metabolite concentrations were determined from the RD collected at 2-h intervals and from the blood taken by jugular puncture, respectively. The SNAN fractions (free amino acid, peptide and soluble protein) in RD and OD collected at 2-h intervals were assessed by ninhydrin assay. Mean ruminal ammonia concentrations were 40.5, 74.8, 103.4 and 127.0 mg/L for low CGM, high CGM, low SBM and high SBM, respectively, with statistically significant differences (p<0.01 for CP level and p<0.001 for CP degradability). Blood urea nitrogen concentrations were increased by high CP level (p<0.001) but unaffected by CP degradability. There was a significant (p<0.05) interaction between level and degradability of CP on blood albumin concentrations. Albumin was decreased to a greater extent by increasing degradability of low CP diets (0.26 g/dl) compared with high CP diets (0.02 g/dl). Concentrations of each SNAN fraction in RD (p<0.01) and OD (p<0.05) for high CP diets were higher than those for low CP diets, except for peptides but concentrations of the sum of peptide and free amino acid in RD and OD were significantly higher (p<0.05) for high CP diets than for low CP diets. Soybean meal diets increased free amino acid and peptide concentrations in both RD (p<0.01) and OD (p<0.05) compared to CGM diets. High level and greater degradability of CP increased (p<0.001) mean concentrations of total SNAN in RD and OD. These results suggest that RDP contents, increased by higher level and degradability of dietary protein, may increase release of free amino acids, peptides and soluble proteins in the rumen and omasum from ruminal degradation and solubilization of dietary proteins. Because SNAN in OD indicates the terminal product of ruminal metabolism, increasing CP level and degradability appears to increase the amount of intestine-available nitrogen in the liquid phase.