Influence of African Multipurpose Trees on Activity of Rumen Protozoa and Bacteria in Vitro

The engulfment and digestion of bacteria by ciliate protozoa leads to elevated ruminal ammonia concentrations and reduced microbial protein flow from the rumen. Thus it has been suggested that the removal of protozoa from the rumen (defaunation) may be beneficial in animals fed low protein diets (Bird and Leng, 1978). However, existing laboratory methods for defaunation are unsuitable for practical usage. Here we investigated the effects of leaves from various African multipurpose trees (MPT) on the activities of rumen bacteria and protozoa in the hope of identifying naturally occurring defaunating agents.Protozoa are responsible for over 90% of the bacterial protein turnover in the rumen (Wallace and McPherson, 1987), thus the breakdown of bacterial protein was used as an assay of protozoal activity. [14CJ-Leucine-labelled Selenomonas ruminantium was incubated in vitro with rumen fluid taken from four rumen-fistulated sheep receiving a diet of hay, molasses, fishmeal and a mineral and vitamin mixture (500, 299.5,100,91 and 9.5 g/kg respectively). Wheat straw (40 mg/ml) or a 70:30 mixture of straw and MPT was added 2 h before the addition of labelled bacteria. Samples were removed hourly for up to 4 h to follow bacterial degradation. Unlabelled leucine (2.5 mM) was added to the rumen fluid to prevent reincorporation of [14C]-leucine.

Download Full-text

The performance of calves given concentrate diets treated with formaldehyde

Australian Journal of Agricultural Research ◽

10.1071/ar9730613 ◽

1973 ◽

Vol 24 (4) ◽

pp. 613 ◽

Cited By ~ 15

Author(s):

GJ Faichney ◽

HL Davies

Keyword(s):

Food Consumption ◽

Protein Level ◽

Rumen Fluid ◽

Amino Nitrogen ◽

Peanut Meal ◽

Plasma Urea ◽

Protein Levels ◽

Low Protein ◽

Formaldehyde Treatment ◽

Protein Diets

Five groups of Friesian bull calves were given concentrate diets containing 70 % barley in which low (12 %), medium (15 %), and high (19%) protein levels were obtained by varying the amount of peanut meal included. The effects of protein level and of formaldehyde treatment of the complete diet at the low and medium protein levels were studied in terms of liveweight gain, voluntary food consumption, digestibility of the diet, ammonia nitrogen in rumen fluid, and urea and a-amino nitrogen in blood plasma. Observations were begun when the calves reached 70 kg liveweight and continued until they reached 130 kg liveweight. The calves given the low protein diets grew more slowly than those given the higher protein diets. The calves given the high protein diet grew no better than those given the medium protein diets. Formaldehyde treatment was associated with an increase in the rate of liveweight gain of 9% (P = 0.11) at the low protein level but had practically no effect at the medium protein level. The treatment did not adversely affect voluntary food consumption but was associated with decreases in the digestibility of nitrogen and in rumen ammonia levels and small increases in plasma urea levels.

Download Full-text

METABOLISM OF SELENOMETHIONINE IN THE RUMEN

Canadian Journal of Animal Science ◽

10.4141/cjas74-044 ◽

1974 ◽

Vol 54 (3) ◽

pp. 325-330 ◽

Cited By ~ 4

Author(s):

K. J. JENKINS ◽

M. HIDIROGLOU ◽

J. E. KNIPFEL

Keyword(s):

Ion Exchange ◽

Rumen Fluid ◽

In Vitro Study ◽

Exchange Chromatography ◽

Elemental Selenium ◽

Bacterial Protein ◽

Time Intervals ◽

Ruminal Bacteria ◽

Enzymatic Hydrolysate

Five rumen-fistulated wethers were dosed intraruminally with a single dose of 75Se-selenomethionine, and the rumen liquor was collected after various time intervals and separated into bacterial, cell-free, and protozoa plus plant material fractions. Maximum 75Se activity in rumen fluid was observed 2 h after labelled selenomethionine was administered. At 6 h post-dosing, 50% of the rumen liquor label was in the bacterial fraction, decreasing to 20% at 96 h. The majority of bacterial 75Se activity was found to be protein-bound. In a second experiment, five wethers were given 75Se-selenomethionine intraruminally, and 2 h later ruminal bacteria were isolated for identification of selenocompounds in the bacterial protein. Paper chromatographic separation of protein enzymatic hydrolysate showed the presence of selenocystine, selenomethionine, elemental selenium, and 40–50% 75Se activity as unidentifiable components. In an in vitro study, 75Se-selenomethionine was incubated with a rumen bacterial fraction, and ion-exchange and paper chromatography were used to identify selenocompounds formed. The results indicated that 75Se-selenomethionine was metabolized by the bacteria to 75Se-selenocystine, with both selenoamino acids incorporated into bacterial protein. With ion-exchange chromatography, unless carrier selenomethionine was added, 75Se-selenomethionine was degraded and a high proportion of 75Se activity remained on the column.

Download Full-text

The effect of supplementary nickel on urea metabolism in sheep given a low-protein diet

Proceedings of the British Society of Animal Production (1972) ◽

10.1017/s0308229600017190 ◽

1988 ◽

Vol 1988 ◽

pp. 81-81

Author(s):

J.S. Milne ◽

F. G. Whitelaw ◽

J. Price

Keyword(s):

Rumen Fluid ◽

High Energy ◽

Epithelial Tissue ◽

Urea Synthesis ◽

Feed Conversion ◽

Low Protein ◽

Degradation Rates ◽

Ruminant Diets ◽

Urea Metabolism ◽

Protein Diets

Rumen bacterial urease is known to be a nickel-dependent enzyme and work in USA has shown that the addition of Ni to ruminant diets can increase the activity of urease in rumen fluid (Spears et al., 1977) and in rumen epithelial tissue (Spears et al., 1979)- In practical feeding trials the addition of 5 ppm Ni has also been shown to increase growth rate and feed conversion efficiency in lambs and steers given high-energy low-protein diets (Spears et al., 1979; Spears, 1984). On the basis of these findings it has been suggested that Ni acts by virtue of its effect on rumen urease activity to enhance the recycling of urea-N to the rumen when dietary N supply is low (Spears, 1980). This hypothesis however does not appear to have been tested by direct measurements of the effect of Ni supplements on urea synthesis and degradation rates in ruminants given low protein diets.

Download Full-text

Evidence for a role of the ileum in the control of nitrogen homeostasis via the regulation of arginine metabolism

British Journal Of Nutrition ◽

10.1017/s0007114511000079 ◽

2011 ◽

Vol 106 (2) ◽

pp. 227-236 ◽

Cited By ~ 4

Author(s):

G. Ventura ◽

C. Moinard ◽

F. Sinico ◽

V. Carrière ◽

V. Lasserre ◽

...

Keyword(s):

Direct Action ◽

Arginine Metabolism ◽

Low Protein ◽

Limited Protein ◽

Protein Supply ◽

Protein Diets

As arginine plays a key role in the regulation of liver ureagenesis, we hypothesised that a modulation of enzymes involved in arginine metabolism within the intestine contributes to the regulation of N homeostasis according to protein supply. Our aim was to study the influence of variations in protein or amino acid (AA) supply on intestinal arginase, glutaminase, ornithine aminotransferase (OAT), argininosuccinate lyase and argininosuccinate synthetase. We evaluated in vivo in rats the responses of these enzymes to short-term (ST, 16 h) and long-term (LT, 15 d) variations in dietary protein (10, 17 or 25 % protein diet). In addition, in order to test whether these responses could involve a direct action of AA on the gene expression and activity of these enzymes, Caco-2/TC7 cells were cultured for 3 d with increasing AA concentrations. In vivo, in the ST, both high- and low-protein diets increased arginase activity in the intestinal mucosa (ST25 %: 46 (sem 2) μmol/g per min and ST10 %: 46 (sem 2) μmol/g per min v. ST17 %: 36 (sem 3) μmol/g per min, P < 0·05). In the LT, OAT expression was increased in the LT10 % group (+277 %, P < 0·05) compared with the LT17 % group. Caco-2/TC7 cells showed inverse relationships between AA supply and arginase (P = 0·058) and OAT (P = 0·035) expressions. The present study demonstrates the regulation of intestinal arginase and OAT expressions in response to protein supply. Our in vitro experiments further indicate a direct AA-induced regulation of the mRNA abundance of these enzymes. In situations of limited protein supply, this regulation would increase intestinal arginine catabolism and, possibly via a decrease in arginine portal release, decrease hepatic AA oxidation, thus promoting N sparing.

Download Full-text

Digestion of rumen bacteria in vitro

British Journal Of Nutrition ◽

10.1079/bjn19830015 ◽

1983 ◽

Vol 49 (1) ◽

pp. 101-108 ◽

Cited By ~ 6

Author(s):

R. J. Wallace

Keyword(s):

Rumen Fluid ◽

Individual Species ◽

Rumen Bacteria ◽

Gram Negative Bacteria ◽

Bacterial Protein ◽

Gram Positive ◽

Gram Negative ◽

Pure Cultures ◽

Mixed Bacteria

1. A pepsin + pancreatin method was used to assess the digestibility of pure cultures of rumen bacteria and mixed bacteria prepared from rumen fluid.2. Individual species of Gram-negative rumen bacteria were highly digestible, whereas Gram-positive species, especially cocci, were more resistant to digestion.3. A similar difference was observed microscopically with mixed rumen bacteria, but the influence of the relative proportions of Gram-positive and Gram-negative bacteria on the digestibility of bacterial protein in rumen fluid was small.

Download Full-text

Differences between sheep and red deer in in vitro apparent and true digestibility of commonly used red deer feeds

Acta agriculturae Slovenica ◽

10.14720/aas.2018.112.1.1 ◽

2018 ◽

Vol 112 (1) ◽

pp. 5

Author(s):

Andrej LAVRENČIČ ◽

Darko VETERNIK

Keyword(s):

Dry Matter ◽

Red Deer ◽

Nutritive Value ◽

Rumen Fluid ◽

Apple Pomace ◽

Host Animal ◽

Grass Silage ◽

Naturally Occurring ◽

True Digestibility

The nutritive value of red deer feeds is frequently determined by sheep despite the ultimate arbitrator of the nutritive value of any feed is the host animal. The objective of the trial was to determine the influence of rumen fluid donor (sheep vs red deer) on in vitro dry matter (DMD), neutral-detergent fibre (NDFD) and true digestibility (ivTD) of eleven substrata, naturally occurring in Slovenian forests (chestnut fruits, acorns of common and sessile oak, two fresh grasses) and those frequently used in supplemental red deer feeding (two grass hays and two grass silages, apple pomace and sugar beet roots). Only the fresh grass from Jelendol had greater (p < 0.05) DMD (646 vs 508 g/kg) when incubated in red deer inoculum. The NDFD and ivTD were always numerically greater when substrates were incubated in red deer inocula, however the NDFD and ivTD were significantly greater (p < 0.05) only when fresh grass from Jelendol (590 vs 343 g/kg and 801 vs 681 g/kg, respectively), grass silage from Kokra (541 vs 359 g/kg and 742 vs 639 g/kg, respectively) and apple pomace (428 vs 328 g/kg and 704 vs 653 g/kg, respectively) were incubated in the inoculum prepared from red deer rumen contents. These results indicate that rumen fluid from sheep can be used to predict in vitro digestibility in red deer and that these parameters can be used in the formulation of deer diets.

Download Full-text

Effect of Methionine Supplementation on Rumen Microbiota, Fermentation, and Amino Acid Metabolism in In Vitro Cultures Containing Nitrate

Microorganisms ◽

10.3390/microorganisms9081717 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1717

Author(s):

Faiz-ul Hassan ◽

Yanxia Guo ◽

Mengwei Li ◽

Zhenhua Tang ◽

Lijuan Peng ◽

...

Keyword(s):

Amino Acid ◽

Volatile Fatty Acids ◽

Rumen Fluid ◽

Culture Technique ◽

Rumen Microbiota ◽

Ruminal Ph ◽

Ch4 Production ◽

Low Protein ◽

The Individual

This study evaluated the effect of methionine on in vitro methane (CH4) production, rumen fermentation, amino acid (AA) metabolism, and rumen microbiota in a low protein diet. We evaluated three levels of methionine (M0, 0%; M1, 0.28%; and M2, 1.12%) of in the presence of sodium nitrate (1%) in a diet containing elephant grass (90%) and concentrate (10%). We used an in vitro batch culture technique by using rumen fluid from cannulated buffaloes. Total gas and CH4 production were measured in each fermentation bottle at 3, 6, 9, 12, 24, 48, 72 h of incubation. Results revealed that M0 decreased (p < 0.001) the total gas and CH4 production, but methionine exhibited no effect on these parameters. M0 decreased (p < 0.05) the individual and total volatile fatty acids (VFAs), while increasing (p < 0.05) the ruminal pH, acetate to propionate ratio, and microbial protein content. Methionine did not affect ruminal AA contents except asparagine, which substantially increased (p = 0.003). M2 increased the protozoa counts, but both M0 and M1 decreased (p < 0.05) the relative abundance of Firmicutes while increasing (p < 0.05) the Campilobacterota and Proteobacteria. However, Prevotella and γ-Proteobacteria were identified as biomarkers in the nitrate group. Our findings indicate that methionine can increase ruminal asparagine content and the population of Compylobactor.

Download Full-text

Factors affecting the rate of breakdown of bacterial protein in rumen fluid

British Journal Of Nutrition ◽

10.1079/bjn19870098 ◽

1987 ◽

Vol 58 (2) ◽

pp. 313-323 ◽

Cited By ~ 81

Author(s):

R. J. Wallace ◽

Carol A. McPherson

Keyword(s):

Protein Turnover ◽

Rumen Fluid ◽

Minor Importance ◽

Bacterial Protein ◽

Protein Breakdown ◽

Factors Affecting ◽

Selenomonas Ruminantium ◽

Endogenous Protein ◽

Live Bacteria ◽

Soluble Material

1. The cellular proteins ofButyrivibrio jibrisolvens, Lactobacillus casei, Megasphaera elsdenii, Selenomonas ruminantiumandStreptococcus boviswere labelled by growth in the presence of L-[14C]leucine, and the breakdown of labelled protein was measured in incubations of these bacteria with rumen fluid to which unlabelled 5 mM-L-leucine was added. The rate of protein breakdown was estimated from the rate of release of radioactivity into acid-soluble material.2. Protein breakdown occurred at different rates in different species. The mean rates for B.fibrisolvens, L. casei, M. elsdenii, Sel. ruminantiumandStr. boviswere 28.6, 18.1, 17.7, 10.5 and 5.3% /h respectively in samples of strained rumen fluid (SRF) with different protozoal populations. Rates of 3% /h or less were found in SRF from ciliate-free sheep or in faunated SRF from which protozoa had been removed by centrifugation. Further removal of mixed rumen bacteria had little effect. Suspensions of washed protozoa degraded bacterial protein at rates which were of the same order as those found in SRF.3. The rate of breakdown of bacterial protein in different samples of SRF tended to increase as the numbers of small entodiniomorphid protozoa increased. The numbers of larger entodiniomorphs and holotrichs had no obvious influence on this rate.4. Autoclaved and u.v.-treated bacteria were generally no different from live bacteria in their susceptibility to breakdown in SRF from faunated sheep, indicating that endogenous protein turnover was not a significant cause of bacterial protein catabolism.5. The rate of bacterial protein breakdown was unrelated to the proteolytic activity of SRF.6. It was concluded that predation by small protozoa is by far the most important cause of bacterial protein turnover in the rumen, with autolysis, other lytic factors and endogenous proteolysis being of minor importance.

Download Full-text

Rumen fermentation and microbial yield of high- or low-protein diets containing ground soybean seeds or homemade rapeseed expellers evaluated with RUSITEC

Canadian Journal of Animal Science ◽

10.4141/cjas2013-007 ◽

2013 ◽

Vol 93 (3) ◽

pp. 363-371 ◽

Cited By ~ 1

Author(s):

M. Guadagnin ◽

F. Tagliapietra ◽

M. Cattani ◽

S. Schiavon ◽

H. J. Worgan ◽

...

Keyword(s):

Fatty Acids ◽

Dry Matter ◽

Microbial Growth ◽

Volatile Fatty Acids ◽

Rumen Fermentation ◽

Soybean Seeds ◽

Low Protein ◽

Ground Soybean ◽

Protein Diets

Guadagnin, M., Tagliapietra, F., Cattani, M., Schiavon, S., Worgan, H. J., Belanche, A., Newbold, C. J. and Bailoni, L. 2013. Rumen fermentation and microbial yield of high- or low-protein diets containing ground soybean seeds or homemade rapeseed expellers evaluated with RUSITEC. Can. J. Anim. Sci. 93: 363–371. This experiment aimed to compare diets containing two crude protein (CP) concentrations [147 or 109 g kg−1in dry matter (DM)] and two protein sources containing ground soybean seed (GSS) or rapeseed expeller (RSE). Diets were compared in terms of digestibility, volatile fatty acids (VFA) and ammonia concentrations, and N flows, using rumen simulation fermenters (RUSITEC). Home−made RSE (CP=287 g kg−1dry matter and ether extract=199 g kg−1DM) was produced using equipment adopted by small farms. Reduction of dietary CP content did not affect digestibility, except for a reduction of N apparent digestibility (P<0.01), but increased efficiency of N utilization (P=0.001) without affecting microbial N production (P=0.82). Total VFA concentration was not (P=0.56) influenced by CP content. Compared with GSS, RSE exhibited a greater neutral detergent fibre digestibility (P<0.01), it did not influence total volatile fatty acids (VFA; P=0.10) but decreased the proportions of acetate and propionate on total VFA (P<0.001) and increased those of butyrate and branched-chain VFA (P<0.001). Microbial efficiency was comparable for GSS and RSE. Results suggest that reduction of dietary CP concentration in DM did not impair in vitro digestibility and microbial growth. The protein mixture containing homemade RSE showed in vitro fermentative properties and microbial growth comparable with those of GSS.

Download Full-text