In situ rumen degradation of kernels from short-season corn silage hybrids as affected by processing1,2

Abstract The objective of this in situ study was to evaluate the rumen degradability of kernels from short-season corn hybrids grown for silage in Western Canada (Lacombe, AB) and determine whether decreasing kernel particle size would enhance ruminal degradability in a similar manner for all hybrids. The study was a completely randomized design with 3 beef cows (replicates) and a 6 (hybrid) × 3 (particle size) factorial arrangement of treatments. Kernels were processed to generate three different particle sizes: large (2.3 mm), medium (1.4 mm), and small (0.7 mm). Processed samples were incubated in the rumen for 0, 3, 6, 12, 24, and 48 h using the in situ method and degradation kinetics of DM and starch were determined. Effective rumen degradability (ED) was estimated using a passage rate of 0.04 (ED4), 0.06 (ED6), and 0.08/h (ED8). Hybrids exhibited a range in whole plant DM content (23.7 to 25.0%), starch content (15.9 to 28.1% DM), kernel hardness (21.9 to 34.4 s/20 g) and density (3.57 to 4.18 g/mL), and prolamin content (8.24 to 11.34 g/100 g starch). Differences in digestion kinetics among hybrids were generally more pronounced for starch than DM. The hybrids differed in starch degradability (P < 0.05), with earlier maturing hybrids having lower A fraction, lower kd, and lower ED, with hybrid effects on ED being accentuated with faster passage rate. Kernel DM content (r = −0.85, −0.87), hardness (r = −0.89, −0.86), and density (r = −0.84, −0.85) were negatively correlated with ED4 and ED8 of starch, respectively, due mainly to decreased kd of fraction B. Reducing the particle size of kernels increased ED of starch due to increased A fraction and kd of the B fraction. A tendency (P = 0.09) for hybrid × processing effects for ED6 and ED8 indicated that processing had greater effects on increasing ED of starch for earlier maturing hybrids. We conclude that short-season hybrids that mature early may have lower ED of DM and starch and would benefit from prolonged ensilage time. Kernel processing during silage making is recommended for short-season corn hybrids as a means of enhancing rumen availability of starch.

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Influence of Particle Charge and Size Distribution on Triboelectric Separation—New Evidence Revealed by In Situ Particle Size Measurements

Processes ◽

10.3390/pr7060381 ◽

2019 ◽

Vol 7 (6) ◽

pp. 381 ◽

Cited By ~ 2

Author(s):

Johann Landauer ◽

Petra Foerst

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Starch Content ◽

Dynamics Simulation ◽

Height Distribution ◽

Particle Charge ◽

Separation Chamber ◽

Triboelectric Charging

Triboelectric charging is a potentially suitable tool for separating fine dry powders, but the charging process is not yet completely understood. Although physical descriptions of triboelectric charging have been proposed, these proposals generally assume the standard conditions of particles and surfaces without considering dispersity. To better understand the influence of particle charge on particle size distribution, we determined the in situ particle size in a protein–starch mixture injected into a separation chamber. The particle size distribution of the mixture was determined near the electrodes at different distances from the separation chamber inlet. The particle size decreased along both electrodes, indicating a higher protein than starch content near the electrodes. Moreover, the height distribution of the powder deposition and protein content along the electrodes were determined in further experiments, and the minimum charge of a particle that ensures its separation in a given region of the separation chamber was determined in a computational fluid dynamics simulation. According to the results, the charge on the particles is distributed and apparently independent of particle size.

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In situ rumen degradation characteristics of sixty cultivars of barley grain

Canadian Journal of Animal Science ◽

10.4141/a99-118 ◽

2000 ◽

Vol 80 (4) ◽

pp. 691-701 ◽

Cited By ~ 22

Author(s):

G. R. Khorasani ◽

J. Helm ◽

J. J. Kennelly

Keyword(s):

Starch Content ◽

Genetic Selection ◽

Barley Grain ◽

Kernel Weight ◽

Test Weight ◽

Barley Cultivars ◽

Rumen Degradation ◽

Key Words Barley ◽

Ruminal Digestion

Our objectives were to determine the extent of genetic variability in the rate and extent of ruminal digestion among 60 cultivars of barley, and to evaluate the correlations between ruminal digestion characteristics and chemical composition and test weight of barley cultivars. Barley samples were ground through a 2-mm screen, and bags containing 1 g of ground grains were incubated in the rumen of three late-lactation Holstein cows with rumen cannulae for 0, 1, 2, 4, 8, 12, 16, and 24 h. The rate and extent of ruminal digestion were estimated. The insoluble DM fraction ranged from 33.4 to 56.4%, the degradable DM fraction ranged from 34.1 to 60.2%, and the rate of degradation of DM ranged from 0.200 h−1 to 0.624 h−1. Hulled barley cultivars had lower (P < 0.05) soluble and degradable fractions than hulless cultivars. The soluble fraction was positively correlated to starch content of barley cultivars (P = 0.01) and the degradable fraction was correlated to the test weight and CP content (P < 0.01). The observed variability in the ruminal digestion characteristics of barley cultivars indicates that genetic selection holds promise as a means of enhancing the nutritional quality of barley for ruminants. We also observed that 70% of the variation in digestibility could be explained by measures of bulk density, starch content, and kernel weight. Key words: Barley cultivars, in situ degradability

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Effect of particle size on in situ ruminal disappearances of pea (Pisumsativum) organic matter, proteins and starch in dairy cows

Canadian Journal of Animal Science ◽

10.4141/a98-105 ◽

2000 ◽

Vol 80 (1) ◽

pp. 203-206 ◽

Cited By ~ 6

Author(s):

C. Bayourthe ◽

R. Moncoulon ◽

F. Enjalbert

Keyword(s):

Particle Size ◽

Organic Matter ◽

Dairy Cows ◽

Crude Protein ◽

Rumen Degradation ◽

Pea Flour ◽

Effect Of Particle Size ◽

Pea Seeds ◽

In Sacco

Ruminal disappearance characteristics of OM, CP and starch relative to particle size of dehulled pea seeds were determined using the in sacco method. Fine grinding (≤502 µm) highly increased the rapidly CP and starch degradable fractions and the rate of degradation of these nutrients. Key words: Pea flour, particle size, rumen degradation, crude protein, starch

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In situ rumen degradation kinetics as affected by type of pasture and date of harvest

Scientia Agricola ◽

10.1590/s0103-90162013000600005 ◽

2013 ◽

Vol 70 (6) ◽

pp. 405-414 ◽

Cited By ~ 5

Author(s):

Juan Pablo Keim ◽

Ximena Valderrama ◽

Daniel Alomar ◽

Ignacio Fernando López

Keyword(s):

Degradation Kinetics ◽

Rumen Degradation

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PSIX-17 Investigation of rumen starch and protein degradation kinetics in relation to corn processed by super-conditioned pelleting, extruding and puffing

Journal of Animal Science ◽

10.1093/jas/skaa278.721 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 412-413

Author(s):

Atieh - Rahimi ◽

Abbasali Naserian ◽

Reza Valizadeh ◽

Abdolmansour Tahmasebi ◽

Hesam Dehghani ◽

...

Keyword(s):

Protein Degradation ◽

Soluble Fraction ◽

Degradation Kinetics ◽

Melting Zone ◽

Rumen Degradation ◽

Fractional Rate ◽

Hot Air ◽

Randomized Design ◽

Conditioning Temperature ◽

Corn Processing

Abstract The objective of this study was to investigate the rumen dry matter (DM), starch and protein degradation kinetics of an Iranian corn grain (single crass 702) processed using different thermal processing methods including 1) grinding (G, 2mm), 2) super-conditioned pelleting (SCP; moisture 20%, retention time 6 min and conditioning temperature 95°C), 3) puffing (PUF; puffing temperature 200°C, hot air velocity 25 m/s, feed rate 100 g/m) and 4) extruding (EX; moisture 20%, temperature of melting zone 75°C and die zone 125°C and time 150s). Three lactating Holstein cows fitted with a ruminal cannula were used. Samples were incubated into the rumen for 2, 4, 8, 12, 24, and 48 h. Rumen degradation kinetics were fitted based on equations. Data were analyzed by GLM procedure of SAS (P < 0.05) using a completely randomized design with 6 replications for every treatment. Rapidly soluble fraction (a) and fractional rate constant (c) of DM were higher (P < 0.01) in PUF and EX corns than SCP. The lowest (P < 0.05) slowly degradable fraction (b) of DM was found in SCP. The highest (P < 0.01) effective rumen degradability of DM (ERDM), starch (ERDS) and protein (ERDP) were observed in the EX, followed by PUF, SCP and G corns. Fraction a of starch and protein was significantly greater (P < 0.01) in EX, PUF and SCP than G. The rate of degradability (c) of starch, DM and protein in EX and PUF were similar and higher (P < 0.01) than SCP and G, but c for starch in EX was greater (P < 0.01) than PUF and fallowed by SCP and G corns. In conclusion, the super-conditioning of corn as a new method of corn processing increased rapidly soluble fraction starch similar to PUF and EX corns and effective rumen degradability of starch was significantly increased in SCP corn.

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In situ rumen degradation kinetics of timothy and alfalfa as affected by cultivar and stage of maturity

Canadian Journal of Animal Science ◽

10.4141/a03-116 ◽

2004 ◽

Vol 84 (2) ◽

pp. 255-263 ◽

Cited By ~ 18

Author(s):

P. Yu ◽

D. A. Christensen ◽

J. J. McKinnon

Keyword(s):

Degradation Kinetics ◽

Lag Time ◽

Phleum Pratense ◽

Neutral Detergent Fiber ◽

Order Kinetic ◽

Rumen Degradation ◽

Degradation Pattern ◽

Timothy 2 ◽

Full Head

The objective of this study was to investigate the effects of cultivar and stage of maturity at cutting on rumen degradation characteristics of some feed components in alfalfa (Medicago sativa L.) and timothy (Phleum pratense L.). Two adapted cultivars of alfalfa (Pioneer and Beaver) and timothy (Climax and Joliette), grown in Saskatchewan (Canada), were cut at three stages: 1 = 1 wk before commercial cut (early bud for alfalfa; joint for timothy); 2 = at commercial cut (late bud for alfalfa; pre-bloom head for timothy); 3 = 1 wk after commercial cut (early bloom for alfalfa; full head for timothy). Rumen degradation characteristics, including rapidly degradable fraction (A), potentially degradable fraction (B), undegradable fraction (C), degradation rate (Kd), lag time (T0), and effective degradability (ED) of each component, were determined using in situ technique and analyzed by first order kinetic equation described by Ørskov and McDonald with lag time. The results showed that, in alfalfa, the cultivars have no effect on rumen degradation characteristics of dry matter (DM), organic matter (OM), crude protein (CP), and neutral detergent fiber (NDF) and acid detergent fiber (ADF). However, the stage of maturity at cutting has large effects on each component, except CP. Generally, with increasing stage of maturity, it decreased A or B and increased C without affecting Kd and T0, thus resulting in decreasing the ED fraction. In timothy, the cultivars have effects only on rumen degradation characteristics of CP. Climax has a higher effective degradability of CP (EDCP) than Joliette. The stage of maturity at cutting has a large impact on rumen degradation characteristics of each component. Increasing stage of maturity did not affect A, but reduced B and increased C without affecting Kd and T0, thus resulting in reducing ED fraction. In conclusion, Pioneer and Beaver alfalfa have similar rumen degradation characteristics for all feed components. Climax and Joliette timothy were different only on CP degradation pattern with Climax having a higher EDCP fraction than Joliette. The stage of maturity at cutting had a significant impact on rumen degradation characteristics for both forages. Generally, it decreased ED with increasing stage of maturity. Our results indicate that it is inappropriate to assume fixed degradation characteristics for a forage without considering factors such as stage of maturity at cutting. Key words: Chemical component, rumen degradation characteristics, forage, cultivar, maturity

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In vitro fermentation and in situ rumen degradation kinetics of summer forage brassica plants

Animal Production Science ◽

10.1071/an17534 ◽

2019 ◽

Vol 59 (7) ◽

pp. 1271 ◽

Cited By ~ 6

Author(s):

Juan P. Keim ◽

Jaime Cabanilla ◽

Oscar A. Balocchi ◽

Rubén G. Pulido ◽

Annick Bertrand

Keyword(s):

Chemical Composition ◽

Degradation Kinetics ◽

Gas Production ◽

In Vitro Fermentation ◽

Fermentation Products ◽

Rumen Degradation ◽

Kinetics Of ◽

Forage Rape

The aim of the present study was to assess and compare the nutrient concentration, the in vitro fermentation and the in situ rumen degradation characteristics of Brassica rapa ssp. rapa L. (turnips) and Brassica napus ssp. biennis L. (forage rape). Five varieties of each species were established in three field replicates and were organised in a randomised complete-block nested design. All varieties were harvested and further analysed for chemical composition, in vitro gas-production kinetics, volatile fatty acid (VFA) production and in situ degradation kinetics of dry matter (DM) and crude protein. Turnips showed higher ash, total sugars, raffinose, sucrose, glucose and fructose concentrations (P < 0.001) than did forage rape. Turnip varieties differed in their sucrose, glucose, fructose and total soluble sugar concentration (P < 0.001), whereas rape varieties differed in their neutral detergent fibre concentration (P = 0.004) and digestible organic matter on a DM basis (P < 0.01). Regarding DM-degradation parameters, turnips had a higher soluble fraction ‘a’ (P < 0.01) and a lower insoluble, but potentially degradable fraction ‘b’ (P < 0.01) than did rape, but the fractional degradation rate ‘c’ (0.18/h) was similar to that of rape. Rates of gas production were slightly higher (P = 0.018) for turnip than for rape. No effects for brassica species nor for varieties within species were detected (P > 0.05) for total in vitro VFA production, as well as for the relative proportions of acetate, propionate, butyrate, branch chained VFA and the actetate:propionate ratio. Our study showed that most of the differences that were observed in terms of chemical composition and degradation kinetics did not result in differences in in vitro fermentation products.

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PSXII-8 Effects of fat matrix and particle size of coated methionine on by-pass fraction of dry matter and nitrogen

Journal of Animal Science ◽

10.1093/jas/skz258.820 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 413-414

Author(s):

Leandro Royo ◽

Mónica Puyalto ◽

Trinidad De Evan ◽

Juan José Mallo ◽

Maria Dolores Carro

Keyword(s):

Particle Size ◽

Fixed Effects ◽

Dry Matter ◽

Cold Water ◽

Passage Rate ◽

Mixed Effect ◽

Palm Fatty Acid Distillate ◽

Effect Model ◽

Ruminal Degradation

Abstract The aim of this study was to evaluate the By-Pass fraction (BPF) of the dry matter (DM) and nitrogen (N) of coated methionine with different fat matrix (FM) and particle size (PS). Two FM (Hydrogenated Stearin, HS, and Hydrogenated Palm Fatty Acid Distillate, HPFAD) and four PS (< 500, 500–750, 750–1400, and >1400 µm) were evaluated in an in situ trial with three rumen-cannulated sheep. Intact samples (1 g) were weighed into nylon bags and incubated in the rumen for 2, 4, 8, 12 and 24 h; process repeated twice in each sheep. After extraction from the rumen, the bags were washed with cold water, frozen and lyophilized, before determining N content in the incubation residue. Effective degradability of DM and N was calculated for a rumen passage rate of 0.08/h-1 according to Ørskov and McDonald (1979), and the BPF was calculated as 100 minus the effective degradability. Data were analyzed using a mixed-effect model, with FM, PS and FMxPS interaction as fixed effects and sheep as random; means were compared with LSD test (P ≤ 0.05). HS-coated methionine had higher values of BPF of DM and N (78.2 and 49.6%, respectively; values averaged for all PS; P < 0.001) than HPFAD-coated methionine (64.4 and 17.7%, respectively). There was an interaction between FM and PS (P < 0.001) for BPF of DM and N. Increasing PS of HS-methionine augmented the BPF from 68.9 to 90.3% for DM and from 22.9 to 79.8% for N, whereas the increases for PFAD-methionine were lower (from 66.3 to 66.3% for DM, and from 7.5 to 28.6% for N). It is concluded that the use of HS as FM and the increase of PS are valid strategies to improve methionine protection from ruminal degradation, reaching BPF values of 90.3 and 79.8 % for DM and N, respectively.

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Comparison of Chemical Composition and Rumen Degradation Kinetics of Three Forages: Whole Plant Barley, Whole Plant Foxtail Millet and Grass-Legume Hay

Journal of Agricultural Science ◽

10.5539/jas.v8n6p1 ◽

2016 ◽

Vol 8 (6) ◽

pp. 1

Author(s):

H. A. Lardner ◽

R. Kumar ◽

E. Darambazar ◽

D. Damiran ◽

J. J. McKinnon

Keyword(s):

Chemical Composition ◽

Crude Protein ◽

Nutritive Value ◽

Soluble Fraction ◽

Degradation Kinetics ◽

Foxtail Millet ◽

Neutral Detergent Fiber ◽

Rumen Degradation ◽

Whole Plant

The objective of this study was to determine the chemical composition and in situ rumen degradability of whole plant barley (Hordeum vulgare), whole plant foxtail millet (Setaria italica) and smooth bromegrass (Bromus inermis Leyss)-alfalfa (Medicago sativa L.) (grass-legume) hay, collected during a companion field grazing study. Relative to grass-legume hay, barley and millet were higher (P = 0.05) in crude protein (CP) and soluble CP, and lower (P = 0.02) in neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin, neutral detergent insoluble CP, and acid detergent insoluble crude protein. The potentially undegradable fraction of CP averaged 32% lower for barley and millet, compared to grass-legume hay, while CP soluble fraction was 36 and 64% higher (P < 0.05) for barley and millet, respectively, than for grass-legume hay. Millet had the highest NDF degradability (P = 0.03) and grass-legume hay the least. Barley and millet had greater (P = 0.02) effective degradability of dry matter (DM), CP, and NDF than grass-legume hay. Millet had the highest (P = 0.01) degradable and lowest undegradable fractions of DM and NDF, and lowest soluble fraction of NDF and rate of CP degradation (P < 0.05). Results indicate that whole plant barley and millet have greater nutritive value than grass-legume hay and may be suitable annual forages for extensive grazing.

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In situ rumen degradation of dry matter and crude protein in ewes and dairy cows

Animal Science ◽

10.1017/s1357729800050827 ◽

1999 ◽

Vol 68 (4) ◽

pp. 801-808 ◽

Cited By ~ 8

Author(s):

L. B. J. Šebek ◽

H. Evererts

Keyword(s):

Dairy Cows ◽

Cold Exposure ◽

Crude Protein ◽

Dry Matter ◽

Degradation Kinetics ◽

Clear Trend ◽

Rumen Degradation ◽

Degradation Rates ◽

Reference Protein

AbstractComparative studies were performed on the in-situ rumen degradation rate (kd) and the in-situ rumen undegradable residue (U) of dry matter (DM) and crude protein (CP) in sheep and dairy cows. The effect of different treatmentsfor sheep were investigated together with the validity of using cow-based reference protein values of foods for sheep. The effect of different breeds (Texel ewes and crossbred ewes), dietary roughage: concentrate ratio and shearing (mild cold exposure) were investigated for sheep.The in-situ rumen incubations were performed in accordance with standard operational procedures which were comparable for both species. The foods under consideration were hay and concentrates. Cows displayed lower (DM 0·53 , CP 0·86) Kds than sheep for concentrates.For hay a clear trend between cows and sheep was not observed but cows displayed 0·40 lower Kds than Texel ewes and 0·30 higher Kds than crossbred ewes. For concentrates U levels did not differ between species but for hay cows had 0·45 higher U values than Texel ewes. Texel ewes showed 0·45 higher Kd and 0·35 lower U for DM and CP than crossbred ewes. Dietary roughage: concentrate ratio in sheep diets did not influence the Kds and Us of the foods under consideration. Shearing of crossbred ewes increased Kd of CP by 0·25 and reduced U for DM and CP by 0·20 and 0.24 .In conclusion different in situ rumen degradation rates were found between dairy cows and sheep. This probably makes using reference protein values of foods invalid for sheep since they are based on data for cows. Differences (Kd andU) were also found between sheep breeds and between unshorn and shorn crossbred ewes (mild cold exposure). No effect on rumen degradation kinetics could be attributed to dietary roughage: concentrate ratio.

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