scholarly journals Effects of an exogenous enzyme preparation on microbial protein synthesis, enzyme activity and attachment to feed in the Rumen Simulation Technique (Rusitec)

2001 ◽  
Vol 85 (3) ◽  
pp. 325-332 ◽  
Author(s):  
Y. Wang ◽  
T. A. McAllister ◽  
L. M. Rode ◽  
K. A. Beauchemin ◽  
D. P. Morgavi ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Enzyme Preparation ◽  
Xylanase Activity ◽  
Barley Grain ◽  
Simulation Technique ◽  
Microbial Protein ◽  
Microbial Protein Synthesis ◽  
Exogenous Enzyme ◽  
Alfalfa Hay ◽  
N Incorporation

The effects of an exogenous enzyme preparation, the application method and feed type on ruminal fermentation and microbial protein synthesis were investigated using the rumen simulation technique (Rusitec). Steam-rolled barley grain and chopped alfalfa hay were sprayed with water (control, C), an enzyme preparation with a predominant xylanase activity (EF), or autoclaved enzyme (AEF) 24 h prior to feeding, or the enzyme was supplied in the buffer infused into the Rusitec (EI). Microbial N incorporation was measured using (15NH4)2SO4in the buffer. Spent feed bags were pummelled mechanically in buffer to segregate the feed particle-associated (FPA) and feed particle-bound (FPB) bacterial fractions. Enzymes applied to feed reduced neutral-detergent fibre content, and increased the concentration of reducing sugars in barley grain, but not alfalfa hay. Ruminal cellulolytic bacteria were more numerous with EF than with C. Disappearance of DM from barley grain was higher with EF than with C, but alfalfa was unaffected by EF. Treatment EF increased incorporation of15N into FPA and FPB fractions at 24 and 48 h. In contrast, AEF reduced the 24 h values, relative to C; AEF and C were similar at 48 h. Infused enzyme (EI) did not affect15N incorporation. Xylanase activity in effluent was increased by EF and EI, compared to C, but not by AEF. Xylanase activity in FPA was higher at 48 h than at 24 h with all treatments; it was higher with EF than C at 24 and 48 h, but was not altered by AEF or EI. Applying enzymes onto feeds before feeding was more effective than dosing directly into the artificial rumen for increasing ruminal fibrolytic activity.

scholarly journals EFFECT OF FORAGE AMOUNT AND PARTICLE SIZE IN DIETS OF LACTATING DAIRY COWS ON SITE OF DIGESTION AND MICROBIAL PROTEIN SYNTHESIS

1985 ◽  
Vol 65 (1) ◽  
pp. 101-111 ◽  
Author(s):  
L. M. RODE ◽  
D. C. WEAKLEY ◽  
L. D. SATTER
Keyword(s):  
Particle Size ◽  
Protein Synthesis ◽  
Dry Matter ◽  
Turnover Rate ◽  
Microbial Protein ◽  
Acid Detergent Fiber ◽  
Microbial Protein Synthesis ◽  
Lactating Dairy Cows ◽  
Alfalfa Hay ◽  
Concentrate Level

Lactating Holstein cows fitted with ruminal and duodenal T-type cannulae were used in two studies to determine the effect of forage: concentrate ratio and forage particle size on site of nutrient digestion and microbial protein synthesis. In exp. 1, cows were fed alfalfa hay at 24, 38, 58 and 80% of total dry matter intake. Organic matter (OM) digestion in the total tract (OMD) increased with increasing concentrate level but apparent ruminal OM digestion (AROMD) was unaffected by diet. Digestion of acid detergent fiber (ADF) was similar among the higher forage diets, but was depressed at the 24% forage level. Efficiency of microbial protein synthesis (MPS) was depressed by high concentrate diets and was positively correlated (P < 0.05) to turnover rate within the rumen. In exp. 2, cows were fed 20% concentrate and 80% alfalfa hay in long, chopped or ground and pelleted form. AROMD was lower with ground hay but OMD was unaffected by diet. Digestibility of ADF in the rumen was lower with ground hay, but was partially compensated for by increased hindgut digestion of ADF. Flow of feed plus endogenous nitrogen (N) at the duodenum was 37% and 47% on N intake with long and ground hay, respectively. Efficiency of MPS increased 15% and postruminal N digestion increased 36% when ground hay replaced long hay. Efficiency of MPS was directly related to ruminal solids turnover rate and inversely related to liquid dilution rate. These results demonstrate improvements in efficiency of MPS with either increasing amounts of forage in the diet or increased ruminal passage of solids. Key words: Digestion, microbial protein, rate of passage, cattle, rumen forage

Provision of certain carbohydrate-based supplements to pasture-fed sheep, as well as time of harvesting of the pasture, influences pH, ammonia concentration and microbial protein synthesis in the rumen

2001 ◽  
Vol 41 (1) ◽  
pp. 21 ◽  
Author(s):  
L. M. Trevaskis ◽  
W. J. Fulkerson ◽  
J. M. Gooden
Keyword(s):  
Protein Synthesis ◽  
Nutrient Content ◽  
Barley Grain ◽  
Water Soluble ◽  
Soluble Carbohydrates ◽  
Microbial Protein ◽  
Castrate Male ◽  
Microbial Protein Synthesis ◽  
Rumen Ph ◽  
Kikuyu Grass

A series of experiments was conducted to test the hypothesis that ‘synchronising’ the availability of carbohydrate and nitrogen (N) in the rumen of sheep, either by the feeding of carbohydrate-based supplements in relation to pasture intake or by provision of pasture with a higher ratio of these 2 nutrients, would benefit microbial protein synthesis (MPS). The response variables were rumen pH and ammonia (NH3), and urine allantoin was measured as an indicator of MPS. The animals used were adult castrate male sheep fitted with a rumen cannula. In experiment 1, rumen NH3 and pH were found to be at a maximum and minimum, respectively, 1–2 h after feeding kikuyu (Pennisetum clandestinum) grass and 3–4 h after feeding biennial ryegrass (Lolium multiflorum) with rumen N degradability (at 18 h in sacco) being 55 and 75%, respectively. In experiment 2, the infusion of sucrose at 4 h post-ingestion of ryegrass pasture (the anticipated time of peak rumen NH3 concentration) lowered peak NH3 concentration by 40 mg/dL (from 187 to 147 mg/dL) and raised urine allantoin excretion from 6.0 to 9.0 mmol/sheep.day compared with infusion of sucrose at –1, +1 or +7 h. When sucrose was infused, 1 h after being fed kikuyu (synchronous) at the expected time of peak rumen NH3 concentration, the NH3 peak (from 152 to 110 mg/dL) and rumen pH were reduced and urinary allantoin excretion raised (from 6.6 to 7.6 mmol/sheep.day) compared with sheep given sucrose 7 h after ingestion of kikuyu grass (asynchronous). In experiment 3, the feeding of fine-rolled barley grain at, or 2 h before, feeding kikuyu grass, to ‘synchronise’ the availability of rumen-fermentable carbohydrates (RFC) in the grain with the availability of N released from the grass, substantially reduced rumen NH3 and pH, and increased urine allantoin levels (from 10.1 to 11.8 mmol/sheep.day) compared with feeding barley at 4 or 6 h before feeding grass. In experiment 4, sheep were fed kikuyu or ryegrass cut in the early morning (AM) or late afternoon (PM), with the nutrient content varying only in water-soluble carbohydrates (64 v. 114 g/kg DM for ryegrass and 41 v. 80 g/kg DM for kikuyu, respectively) and percentage of dry matter. Sheep fed PM-ryegrass had a significantly lower rumen pH compared with sheep fed AM-ryegrass but there was no difference in rumen NH3 concentrations. Urinary allantoin secretion was substantially higher in the PM group than the AM group (8.7 v. 3.9 mmol/sheep.day). When sheep were fed PM-kikuyu the pH fell to lower values than for the AM-kikuyu (6.4 v. 6.8) and there was again no effect on rumen NH3 levels. Urine allantoin levels were higher (P = 0.006) (6.2 v. 5.6 mmol/ sheep.day) in PM-fed sheep. The results of these studies support the hypothesis that there are benefits in synchronising the availability of RFC with N in the rumen on MPS but this is not always associated with significant changes in rumen pH and NH3. The implications of these results are discussed in relation to the situation in which synchronisation of RFC and N may potentially benefit dairy cattle.

Effects of dietary flaxseed and vitamin E on fermentation, nutrient disappearance, fatty acid biohydrogenation, and microbial protein synthesis using a simulated rumen (Rusitec)

2020 ◽  
Vol 100 (4) ◽  
pp. 691-702
Author(s):  
K. Stanford ◽  
H. Sultana ◽  
M.L. He ◽  
M. Dugan ◽  
T.A. McAllister
Keyword(s):  
Protein Synthesis ◽  
Fatty Acid ◽  
Vitamin E ◽  
Barley Grain ◽  
Neutral Detergent Fiber ◽  
Microbial Protein ◽  
Acid Detergent Fiber ◽  
Microbial Protein Synthesis ◽  
Concentrate Production ◽  
Microbial N

Two simulated rumens (Rusitecs) were used to assess the effects of flaxseed (FS) and (or) vitamin E (VE) on rumen fermentation, fatty acid (FA) biohydrogenation, and microbial protein synthesis. Ground FS replaced 0% or 15% of barley grain, along with VE at 0 or 1000 IU d−1 in a 2 × 2 factorial experiment. Flaxseed lowered neutral detergent fiber (P = 0.001) and acid detergent fiber (P = 0.01) and increased (P = 0.001) nitrogen (N) disappearance. Flaxseed also increased (P = 0.01) total volatile FA and decreased (P = 0.001) acetate production. When both FS and VE were included, the acetate:propionate ratio decreased (P = 0.04). Biohydrogenation of FA was not influenced by VE, but total FA and C18:0 in effluent were increased (P = 0.001) and C16:0 decreased (P = 0.001) by FS. With VE, total microbial N (MN) was increased (P = 0.001). In the concentrate, production of MN in feed-particle-bound bacteria was increased (P = 0.001) by VE. Vitamin E did not alter FA biohydrogenation but did promote MN production. The stable and relatively high pH in the Rusitec may have prevented the typical shift from C18:1 trans-11 to C18:1 trans-10 with concentrate diets. Future studies simulating subclinical acidosis in the Rusitec may illuminate ruminal mode(s) of action of VE on FA biohydrogenation.

scholarly journals EFFECT OF AMOUNT AND LENGTH OF ALFALFA HAY IN DIETS CONTAINING BARLEY OR CORN ON SITE OF DIGESTION AND RUMEN MICROBIAL PROTEIN SYNTHESIS IN DAIRY COWS

1988 ◽  
Vol 68 (2) ◽  
pp. 445-454 ◽  
Author(s):  
L. M. RODE ◽  
L. D. SATTER
Keyword(s):  
Protein Synthesis ◽  
Turnover Rate ◽  
Block Design ◽  
Microbial Protein ◽  
Microbial Protein Synthesis ◽  
Alfalfa Hay ◽  
Total Digestion ◽  
Randomized Complete Block Design ◽  
Main Effects ◽  
Microbial N

Eight lactating Holstein cows fitted with simple cannulae in the rumen and proximal duodenum were used in a 2 × 2 × 2 factorial experiment in a randomized complete block design. The factors studied were: (1) forage length (full bloom alfalfa hay, long or chopped); (2) forage level in the total ration (25 or 75%); and (3) type of grain in the concentrate mixes (barley or corn). Organic matter (OM) intake was not affected by level of forage or grain type but was greater (P < 0.05) with chopped hay than with long hay. Apparent total digestion of OM increased (P < 0.01) from 59.7 to 68.1% as forage in the diet decreased from 75 to 25%, but site of digestion was unaffected. Flow to the duodenum of nonammonia-N, feed N, and microbial N were unaffected by forage level, forage length, or grain type. No differences in main effects were observed between corn and barley but interactions between grain type and forage length or amount indicate that type of grain had an influence upon site of OM digestion and flow of nonammonia-N and microbial N from the rumen. Efficiency of microbial protein synthesis (MPS) was positively associated with turnover rate of rumen solids regardless of liquid dilution rate. When no change in turnover rate of solids occurred, efficiency of microbial protein synthesis increased in association with increases in turnover rate of liquid. Key words: Lactation, cattle, bacteria, alfalfa, duodenum, rumen

scholarly journals Effect of exogenous fibrolytic enzymes and ammonia fiber expansion on the fermentation of wheat straw in an artificial rumen system (RUSITEC)1

2019 ◽  
Vol 97 (8) ◽  
pp. 3535-3549 ◽  
Author(s):  
Atef M Saleem ◽  
Gabriel O Ribeiro ◽  
Haley Sanderson ◽  
Daryoush Alipour ◽  
Tassilo Brand ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Wheat Straw ◽  
Block Design ◽  
Xylanase Activity ◽  
Neutral Detergent Fiber ◽  
Microbial Protein ◽  
Endoglucanase Activity ◽  
Fibrolytic Enzymes ◽  
Microbial Protein Synthesis ◽  
Ammonia Fiber Expansion

AbstractThis study investigated the effect of treatment of wheat straw using ammonia fiber expansion (AFEX) and exogenous fibrolytic enzymes (Viscozyme) on fiber digestibility, rumen fermentation, microbial protein synthesis, and microbial populations in an artificial rumen system [Rumen Simulation Technique (RUSITEC)]. Four treatments were assigned to 16 vessels (4 per treatment) in 2 RUSITEC apparatuses in a randomized block design. Treatments were arranged as a 2 × 2 factorial using untreated or AFEX-treated wheat straw with or without exogenous fibrolytic enzymes [0 or 500 μg of protein/g straw dry matter (DM)]. Fibrolytic enzymes were applied to straw, prior to sealing in nylon bags. The concentrate mixture was provided in a separate bag within each fermentation vessel. The RUSITECs were adapted for 8 d and disappearance of DM, neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude protein (CP) was measured after 48 h of incubation. Ammonia fiber expansion increased (P < 0.01) the disappearance of wheat straw DM (69.6 vs. 38.3%), NDF (65.6 vs. 36.8%), ADF (61.4 vs. 36.0%), and CP (68.3 vs. 24.0%). Total dietary DM, organic matter (OM), and NDF disappearance was also increased (P ≤ 0.05) by enzymes. Total microbial protein production was greater (P < 0.01) for AFEX-treated (72.9 mg/d) than untreated straw (63.1 mg/d). Total gas and methane (CH4) production (P < 0.01) were also greater for AFEX-treated wheat straw than untreated straw, with a tendency for total gas to increase (P = 0.06) with enzymes. Ammonia fiber expansion increased (P < 0.01) total volatile fatty acid (VFA) production and the molar proportion of propionate, while it decreased (P < 0.01) acetate and the acetate-to-propionate ratio. The AFEX-treated straw had lower relative quantities of fungi, methanogens, and Fibrobacter succinogenes (P < 0.01) and fewer protozoa (P < 0.01) compared to untreated straw. The pH of fermenters fed AFEX-treated straw was lower (P < 0.01) than those fed untreated straw. Both AFEX (P < 0.01) and enzymes (P = 0.02) decreased xylanase activity. There was an enzyme × straw interaction (P = 0.02) for endoglucanase activity. Enzymes increased endoglucanase activity of AFEX-treated wheat straw, but had no effect on untreated straw. The addition of enzymes lowered the relative abundance of Ruminococcus flavefaciens, but increased F. succinogenes. These results indicate that AFEX increased the ruminal disappearance of wheat straw and improved fermentation and microbial protein synthesis in the RUSITEC.

Effect of protein source on microbial protein synthesis and nutrient digestion in beef cattle fed barley grain-based diets

2004 ◽  
Vol 84 (3) ◽  
pp. 481-490 ◽  
Author(s):  
K. M. Koenig ◽  
K. A. Beauchemin ◽  
L. M. Rode
Keyword(s):  
Protein Synthesis ◽  
Beef Cattle ◽  
Barley Grain ◽  
Protein Supplementation ◽  
Protein Source ◽  
Canola Meal ◽  
Microbial Protein ◽  
Protein Sources ◽  
Microbial Protein Synthesis ◽  
Microbial N

Four British cross heifers fitted with ruminal and duodenal cannulas were used in an experiment designed as a 4 × 4 Latin square. The basal diet was composed of 90% barley grain concentrate and 10% barley silage (DM basis) with either no protein supplementation (13.6% CP), or an additional 1.2% CP (% of DM) in the form of urea, canola meal (CM) or blood meal (BM). Ruminal ammonia N concentration was highest (P < 0.05) for the urea-supplemented diet (111 ± 18 mg N L-1), but no differences were observed among the control, CM- or BM-supplemented diets (59 to 78 mg N L-1; P > 0.05). Ruminal pH averaged 5.78 and was not affected by protein source (P = 0.97). Canola meal and BM tended (P < 0.10) to increase microbial N flow by 31 g N d-1 or 21% above the control diet. The response of microbial N flow to urea supplementation was intermediate between the control and true protein sources (P > 0.10). Ruminal OM and starch digestion were not affected by the dietary treatments (P > 0.10). In conclusion, barley grain-based finishing diets supplemented with protein sources of varying ruminal degradabilities increased microbial protein supply, but the improvement in microbial protein synthesis had no effect on diet fermentability. Key words: Protein supplements, microbial proteins, barley, beef cattle

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