Abstract #W416
Section: Ruminant Nutrition
Session: Ruminant Nutrition: General III
Format: Poster
Day/Time: Wednesday 7:30 AM–9:30 AM
Location: Gatlin Ballroom
Session: Ruminant Nutrition: General III
Format: Poster
Day/Time: Wednesday 7:30 AM–9:30 AM
Location: Gatlin Ballroom
# W416
Varying the degrees of synchrony of energy and nitrogen release in rumen affect the synthesis of microbial protein in continuous culture system.
J. Zhang1, J. Q. Wang1, D. P. Bu*1,2, S. G. Zhao1, P. P. Wang1, X. M. Nan1,3, 1State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China, 2World Agroforestry Centre, East and Central Asia, Beijing, China, 3Synergetic Innovation Center of Food Safety and Nutrition, Harbin, China.
Key Words: synchrony, energy, nitrogen
Varying the degrees of synchrony of energy and nitrogen release in rumen affect the synthesis of microbial protein in continuous culture system.
J. Zhang1, J. Q. Wang1, D. P. Bu*1,2, S. G. Zhao1, P. P. Wang1, X. M. Nan1,3, 1State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China, 2World Agroforestry Centre, East and Central Asia, Beijing, China, 3Synergetic Innovation Center of Food Safety and Nutrition, Harbin, China.
A continuous rumen simulation system apparatus with 16 1000 mL fermentation vessels was used to investigate the effects of different degrees of synchrony between ruminal available energy and nitrogen on rumen fermentation and microbial protein synthesis (MPS). The basal substrate was diet of (g DM/day) 18.50 corn straw, 10.00 corn, 0.26 premix, and 11.24 soybean meal containing 67.5 g N/kg DM, and diets were divided into 2 equal feedings at 09:00 and 21:00 h. The treatments were: the basal diet with (1) 10.0 g maltodextrin which was in the McDougall’s buffer infused continuously into the fermenter (CONT), (2) 10.0 g maltodextrin as 2 6-h infusions starting at 09:00 and 21:00h (FAST) and (3) 10.0 g maltodextrin given as 2 6-h infusions starting at 15:00 and 03:00h (SLOW). Rumen inoculum was obtained from 4 ruminal fistulated cows in early lactation that were fed TMR with 45:55 forage to concentrate ratio. A 8-d incubation period was used, with the first 5 d serving as an adaptation period followed by 3 d of sampling with solid and liquid dilution rates in the fermenters set at approximately 10.0 and 8.0%/h, respectively. Data were analyzed using the MIXED procedure of SAS. All 3 infusion treatments had no significant effect on the apparent digestibility of OM (65.0% for CONT, 62.2% for FAST, and 61.2% for SLOW), DM (66.1%, 63.4% and 63.6%), and CP (71.5%, 68.2% and 68.6%). The pH values among 3 treatments were similar (6.70, 6.68 and 6.71). The concentrations of total volatile fatty acid for CONT and FAST treatments have higher tendency (P = 0.05) than SLOW (79.51 and 77.58 vs. 72.31, mmol/L). However, the CONT and FAST treatments increased (P < 0.05) MPS compared with SLOW (4.0 and 3.8 vs. 2.2, g/day). Compared with SLOW, the lower (P < 0.01) concentration of ammonia in CONT and FAST treatments (7.90 and 8.44 vs. 16.29, mg/dL) may indicate better utilization of ammonia for the growth of ruminal microbe. It is concluded that altering the degree of synchrony in the rates of ruminal release of energy and nitrogen had a marked effect on MPS.
Key Words: synchrony, energy, nitrogen
