• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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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.

• The Korean Journal of Physiology
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• v.16 no.2
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• pp.187-193
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• 1982

The relationship between water and electrolyte metabolism, and dietary intake were studied in 45 healthy Buddhist nuns who were vegetarians aged 20-34, and 28 nursing students aged 20-22 who stayed at the dormitory of Kyungpook Medical School in the Fall, 1981. The Buddhist nuns obtained significantly higher carbohydrate and total caloric intakes but significantly lower protein and lipid intakes than the female students. The Buddhist nuns excreted significantly higher urine output($1,697{\pm}68\;ml/day$, p<0. 05) and lower osmolality ($616{\pm}18\;mOsm/kg\;H_2O$, p<0.05) than the students ($1,505{\pm}67\;ml/day$ and $688{\pm}36\;mOsm/kg\;H_2O$). However, both groups excreted similar amounts of urinary $Na^+$, $K^+$ and total osmolar contents. Free water clearance of the Buddhist nuns was higher(p<0.05) than that of the students but the osmolar clearance was about the same in the two groups. Daily urine output showed good correlation with Na output (r=0.76) and osmolar clearance but not with free water clearance. Both groups showed similar values of plasma concentration of creatinine, daily excretion of creatinine and clearance. Urinary excretion of urea for Buddhist nuns was 6.4 g/day, and was significantly higher than that of the students (5.1g/day).