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

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.

2020 ◽  
Vol 4 (2) ◽  
pp. 839-847
Author(s):  
Daryoush Alipour ◽  
Atef Mohamed Saleem ◽  
Haley Sanderson ◽  
Tassilo Brand ◽  
Laize V Santos ◽  
...  

Abstract This study evaluated the effect of combinations of feed-grade urea and slow-release urea (SRU) on fermentation and microbial protein synthesis within two artificial rumens (Rusitec) fed a finishing concentrate diet. The experiment was a completely randomized, dose–response design with SRU substituted at levels of 0% (control), 0.5%, 1%, or 1.75% of dry matter (DM) in place of feed-grade urea, with four replicate fermenters per dosage. The diet consisted of 90% concentrate and 10% forage (DM basis). The experiment was conducted over 15 d, with 8 d of adaptation and 7 d of sampling. Dry matter and organic matter disappearances were determined after 48 h of incubation from day 9 to 12, and daily ammonia (NH3) and volatile fatty acid (VFA) production were measured from day 9 to 12. Microbial protein synthesis was determined on days 13–15. Increasing the level of SRU quadratically affected total VFA (Q, P = 0.031) and ammonia (Q, P = 0.034), with a linear increment in acetate (L, P = 0.01) and isovalerate (L, P = 0.05) and reduction in butyrate (L, P = 0.05). Disappearance of neutral detergent fiber (NDF) and acid detergent fiber (ADF) was quadratically affected by levels of SRU, plateauing at 1% SRU. Inclusion of 1% SRU resulted in the highest amount of microbial nitrogen associated with feed particles (Q, P = 0.037). Responses in the efficiency of microbial protein synthesis fluctuated (L, P = 0.002; Q, P = 0.001) and were the highest for 1% SRU. In general, the result of this study showed that 1% SRU in combination with 0.6% urea increased NDF and ADF digestibility and total volatile fatty acid (TVFA) production.


2004 ◽  
Vol 84 (3) ◽  
pp. 481-490 ◽  
Author(s):  
K. M. Koenig ◽  
K. A. Beauchemin ◽  
L. M. Rode

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


Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1774
Author(s):  
Rubem R. Rocha Filho ◽  
Djalma C. Santos ◽  
Antonia S. C. Véras ◽  
Michelle C. B. Siqueira ◽  
Carolina C. F. Monteiro ◽  
...  

This study aimed to investigate the effects on nutrient intake and digestibility, milk yield (MY) and composition, milk fatty acids profile, and microbial protein synthesis caused by feeding lactating dairy cows four different forage cactus genotypes. Eight Girolando cows (5/8 Holstein × 3/8 Gyr), weighing 490 ± 69.0 kg (means ± standard deviation), and producing 15.5 ± 1.0 kg/d of milk during pretrial were distributed to two contemporaneous 4 × 4 Latin squares. The cows were fed a total mixed ration composed of sorghum silage (385 g/kg of dry matter (DM)), concentrated mix (175 g/kg DM), and forage cactus (440 g/kg DM). The experimental treatments consisted of different cactus genotypes, such as Gigante cactus (GC), Miúda cactus (MC), IPA Sertânia cactus (SC), and Orelha de Elefante Mexicana cactus (OEMC). The feeding of MC provided a higher intake of DM, organic matter (OM), and total digestible nutrients, as well as higher MY, energy-corrected milk, and microbial protein synthesis in comparison with those resulting from the other genotypes tested. The GC promoted lower DM and OM, and the apparent digestibility of neutral detergent fiber. The cows fed with OEMC showed lower MY and milk protein yield and content, and higher unsaturated over saturated fatty acid ratio in milk. Miúda forage cactus increased nutrient intake, digestibility of DM and OM, and microbial synthesis without impairing the milk fatty acid profile.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 395-395
Author(s):  
Paul Tamayao ◽  
Gabriel O Ribeiro ◽  
Tim A McAllister ◽  
Hee-Eun Yang ◽  
A M Saleem ◽  
...  

Abstract This study investigated the effects of post-pyrolysis treated biochar on nutrient disappearance, total gas and methane (CH4) production, rumen fermentation and microbial protein synthesis in an artificial rumen system (RUSITEC) fed a barley silage-based diet. The basal diet consisted of 60% barley silage, 27% barley grain, 10% canola meal and 3% mineral/vitamin supplement (DM basis). Three spruced-based biochars, treated post-pyrolysis with either zinc chloride, hydrochloric acid/nitric acid mixture or sulfuric acid were added at 2.0% of substrate DM. In a randomized complete block design, treatments were assigned to sixteen vessels (n = 4/treatment) in two RUSITEC systems. The experiment was conducted over 15 d, with 8 d of adaptation and 7 d of sampling. Nutrient disappearance of dry matter (DM), organic matter (OM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) was determined after 48 h of incubation from d 9 to 12, and microbial protein synthesis was measured from d 13–15. Data were analyzed using PROC MIXED in SAS, with the fixed effect of treatment and random effect of RUSITEC system and vessel. Biochar inclusion did not affect disappearance of DM (P = 0.49), OM (P = 0.60), CP (P = 0.14), NDF (P = 0.48), ADF (P = 0.11) or starch (P = 0.58). Biochar also had no effect on total gas production (P = 0.31) or CH4 produced expressed as a % of total gas production (P = 0.06), mg/d (P = 0.70), mg/g of DM incubated (P = 0.74), or mg/g of DM digested (P = 0.64). No effect on total VFA (P = 0.56) or NH3-N (P = 0.20) production were observed. Neither microbial protein synthesis nor total protozoa count were affected by biochar addition (P &gt; 0.05). In conclusion, biochar inclusion in a silage-based diet did not exhibit the potential to mitigate CH4 emissions or improve digestion in a RUSITEC system.


1985 ◽  
Vol 65 (1) ◽  
pp. 101-111 ◽  
Author(s):  
L. M. RODE ◽  
D. C. WEAKLEY ◽  
L. D. SATTER

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


1995 ◽  
Vol 124 (3) ◽  
pp. 463-472 ◽  
Author(s):  
L. A. Sinclair ◽  
P. C. Garnsworthy ◽  
J. R. Newbold ◽  
P. J. Buttery

SUMMARYThe effects of synchronizing dietary energy and nitrogen supply in diets with a similar carbohydrate composition on microbial protein synthesis and rumen fermentation were examined in sheep. Two diets were formulated to be either synchronous (diet S) or asynchronous (diet A) for the hourly release of nitrogen (N) and energy to the rumen. Diet S contained (g/kg) 425 g wheat straw, 400 g winter barley, 150 grapeseed meal and 25 g minerals/vitamins and diet A contained 505 g wheat straw, 458.5 g winter barley, 11·5 g urea and 25 g minerals/vitamins. Both diets were fed at the rate of 1 kg/day in four equal portions, to four cannulated sheep, in two periods in a change-over design. Rumen ammonia concentrations followed the predicted hourly trend in N degradation with a peak 1 h after feeding of 10 mM for diet S and 16 mM for diet A before falling within 3 h of feeding to 4 ITIM in animals fed either diet. Rumen volatile fatty acid (VFA) concentrations followed the cyclical trend predicted by stoichiometric equations, whilst rumen VFA ratios were more stable than predicted in animals fed either diet. The observed content of rumen degradable protein and organic matter truly degraded in the rumen was similar for both diets. The increase in total CHO digested in the rumen observed with diet A (427 g/kg DM) compared with diet S (364 g/kg DM) can be attributed to the greater content of starch in the asynchronous diet, which had a high degradability. The efficiency of microbial protein synthesis (g N/kg OM truly degraded in the rumen) was 11–20% greater in animals fed the synchronous diet (S) than the asynchronous diet (A). It is concluded that microbial N production was more efficient when dietary energy and N supply were synchronized.


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