TY - JOUR
T1 - Evaluation of the fermentation dynamics of soluble crude protein from three protein sources in continuous culture fermenters
AU - Bach, A.
AU - Ruiz Moreno, M.
AU - Thruneand, M.
AU - Stern, M. D.
PY - 2008/6/1
Y1 - 2008/6/1
N2 - Eight dual-flow continuous culture fermenters (1.03 ± 0.05 L) were used to assess differences in microbial degradation of the soluble CP fraction of canola meal (CMSCP), soybean meal (SBMSCP), and fish meal (FMSCP) using a completely randomized design with two 9-d experimental periods and a solution of tryptone as a control treatment (control). All fermenters received the same basal diet (58% ground corn, 40% canary grass hay, 0.4% vitamin-mineral premix, 1% CaCO3, 0.6% salt on a DM basis) in 8 equal portions daily. During sampling on the last 3 d of each period, 90-mL doses containing soluble CP were infused into the fermenters 30 min after the beginning of the first and last feedings of the day. The total amount of soluble CP supplied by the infusions of FMSCP, CMSCP, and SBMSCP was 3.2 g/d, representing 24% of the daily dietary CP intake. Infusion of FMSCP resulted in the greatest (P < 0.05) NH 3-N concentration (4.6 ± 0.40 mg/ dL) compared with the other treatments (0.5 ± 0.40 mg/ dL). Microbial N flow (g/d) from the fermenters was also greatest (P < 0.05) with FMSCP (1.42 ± 0.062) compared with the other soluble CP fractions (1.08 ± 0.062). The efficiency of microbial protein synthesis tended to be lowest with the control diet, and the efficiency of N utilization was lowest with FMSCP treatment. These results indicate that N was limiting microbial growth in the control diet, and there was more rumen-available N with the FMSCP diet compared with the other dietary treatments. The extent of degradation of the soluble CP fraction from fish meal, soybean meal, and canola meal was determined to be 99, 30, and 37% of soluble CP, respectively. These results indicate that the soluble CP fraction is not 100% degraded in all feeds and that assuming a high degradation extent of the soluble CP fraction from soybean meal and canola meal may result in an underestimation of the supply of undegradable protein from these protein sources.
AB - Eight dual-flow continuous culture fermenters (1.03 ± 0.05 L) were used to assess differences in microbial degradation of the soluble CP fraction of canola meal (CMSCP), soybean meal (SBMSCP), and fish meal (FMSCP) using a completely randomized design with two 9-d experimental periods and a solution of tryptone as a control treatment (control). All fermenters received the same basal diet (58% ground corn, 40% canary grass hay, 0.4% vitamin-mineral premix, 1% CaCO3, 0.6% salt on a DM basis) in 8 equal portions daily. During sampling on the last 3 d of each period, 90-mL doses containing soluble CP were infused into the fermenters 30 min after the beginning of the first and last feedings of the day. The total amount of soluble CP supplied by the infusions of FMSCP, CMSCP, and SBMSCP was 3.2 g/d, representing 24% of the daily dietary CP intake. Infusion of FMSCP resulted in the greatest (P < 0.05) NH 3-N concentration (4.6 ± 0.40 mg/ dL) compared with the other treatments (0.5 ± 0.40 mg/ dL). Microbial N flow (g/d) from the fermenters was also greatest (P < 0.05) with FMSCP (1.42 ± 0.062) compared with the other soluble CP fractions (1.08 ± 0.062). The efficiency of microbial protein synthesis tended to be lowest with the control diet, and the efficiency of N utilization was lowest with FMSCP treatment. These results indicate that N was limiting microbial growth in the control diet, and there was more rumen-available N with the FMSCP diet compared with the other dietary treatments. The extent of degradation of the soluble CP fraction from fish meal, soybean meal, and canola meal was determined to be 99, 30, and 37% of soluble CP, respectively. These results indicate that the soluble CP fraction is not 100% degraded in all feeds and that assuming a high degradation extent of the soluble CP fraction from soybean meal and canola meal may result in an underestimation of the supply of undegradable protein from these protein sources.
KW - In vitro
KW - Protein degradation
KW - Soluble protein
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UR - http://www.scopus.com/inward/citedby.url?scp=45549104189&partnerID=8YFLogxK
U2 - 10.2527/jas.2007-0736
DO - 10.2527/jas.2007-0736
M3 - Article
C2 - 18344304
AN - SCOPUS:45549104189
SN - 0021-8812
VL - 86
SP - 1361
EP - 1371
JO - Journal of animal science
JF - Journal of animal science
IS - 6
ER -
