NSC in grass and hay
What is NSC
Analysis of NSC in forage
NSC in grass
NSC in hay
NSC in haylage
General information about grass
Analysis of NSC in forage
NSC in grass
NSC in hay
NSC in haylage
General information about grass
What is NSC?
NSC = non structural carbohydrates. Grass consists of:
structural carbohydrates - what we think of as fibre - cellulose, hemicellulose and lignin (analysed as NDF and ADF on a forage analysis),
non-structural carbohydrates,
protein,
minerals (ash) and vitamins,
oil/fat,
and water.
NSC consists of ESC + fructan + starch, or WSC + starch (same thing).
ESC - ethanol soluble carbohydrates or simple sugars (not quite the same thing but similar - ESC is likely to contain a small amount of short-chain fructans whereas simple sugars (on an analysis) won't include fructans). The simple sugars in grass are mostly glucose and fructose (both monosaccharides) and sucrose (a disaccharide). These simple sugars all directly increase insulin, although glucose increases blood glucose and therefore insulin more significantly. Glucose and fructose are absorbed in the small intestine and need no digestion. Sucrose is digested to glucose and fructose by the enzyme sucrase in the small intestine.
Fructan - fructans are polysaccharides - longer chains of mostly fructose with a glucose, held together by bonds which cannot be digested by enzymes in the horse, but are fermented to acids called both volatile fatty acids (VFA) or short-chain fatty acids (SCFA), and the horse can use these for energy. Although there may be a small amount of pre-cecal (before the hind-gut) fermentation, most fructans reach the hindgut where the microbiome ferments them to VFAs.
ESC plus fructans is termed WSC - water soluble carbohydrates. However, this term is relevant to plant analysis but not to horse nutrition, as ESC and fructans are used by the horse in very different ways.
Starch is a polysaccharide that is (generally) digested by the enzyme amylase to glucose in the small intestine. Starch increases blood glucose and insulin concentrations.
Do these classifications matter to horses?
Yes. Not so much in grass, as sucrose changes into fructans, and fructans back to sucrose, according to photosynthesis sugar manufacture surplus and the plant's requirements for growth. However, when carbohydrate levels are more fixed, as in preserved forages (hay, haylage) or cereals, knowing which carbohydrates are likely to increase blood glucose and insulin concentrations is important for laminitis prevention.
For example, species of ryegrass are being cultivated that have high levels of fructans, so high WSC. If these ryegrass species tended to have lower ESC/simple sugars than "native" grasses such as Timothy, they might make suitable hay or haylage for horses that need low ESC and starch, but are ok with a higher energy value, e.g. older horses. We're not suggesting this is the case, so don't go out and specifically buy ryegrass for your laminitis-prone pony - but until every forage analysis splits ESC from WSC/fructan, we simply won't know and won't be able to make the best decisions for feeding our horses.
Forage analysis must be carried out by wet chemistry for accuracy - NIR analysis is not accurate enough for sugar/carbohydrate analysis.
Currently we are not aware of any forage analysis in the UK or Europe that analyses ESC/simple sugars by wet chemistry on a standard forage analysis, and we recommend that all forage samples are sent to Equi-Analytical in the USA, using #603 Trainer analysis.
Analysis of NSC in forage
Sample preparation
Sample preparation can affect NSC levels in fresh forage.
Pelletier et al. (2010) has shown that freezing can lead to an increase in NSC compared to samples placed directly into the dryer.
P. Udén
The influence of sample preparation on the level of soluble and non-structural carbohydrates in forage crops and silages
Proceedings of the 1st Nordic Feed Science Conference 2010
Pelletier S, Tremblay GF, Betrand A, Belanger G, Castonguay Y, Michaud R
Drying Procedures affect Non-structural Carbohydrates and Other Nutritive Value Attributes in Forage Samples
Animal Feed Science and Technology Feb 2010 157(3-4), 139-150 (Full)
Wet chemistry v NIR
Wet chemistry used for forage analysis of ESC and WSC includes colorimetric phenol-sulphuric acid assay.
Kramer KJ, Kagan IA, Lawrence LM, Smith SR
Ethanol-soluble carbohydrates of cool-season grasses: prediction of concentration by near-infrared reflectance spectroscopy (NIRS) and evaluation of effects of cultivar and management
JEVS published online 19 February 2021 https://doi.org/10.1016/j.jevs.2021.103421
Prince K, Goff B, Lawrence L, Kagan I, Smith R.
Predicting water-soluble carbohydrates and ethanol-soluble carbohydrates in cool-season grasses with near-infrared reflectance spectroscopy.
American Forage and Grassland Council Conference Proceedings 2016. Pg 1.
The above papers (Prince 2016 and Kramer 2021 are linked to:
Prince, Kelly Joan MSc thesis 2017 University of Kentucky
Evaluating nonstructural carbohydrate variation of cool-season grasses based on genotype, management and environment
Sample preparation
Sample preparation can affect NSC levels in fresh forage.
Pelletier et al. (2010) has shown that freezing can lead to an increase in NSC compared to samples placed directly into the dryer.
P. Udén
The influence of sample preparation on the level of soluble and non-structural carbohydrates in forage crops and silages
Proceedings of the 1st Nordic Feed Science Conference 2010
Pelletier S, Tremblay GF, Betrand A, Belanger G, Castonguay Y, Michaud R
Drying Procedures affect Non-structural Carbohydrates and Other Nutritive Value Attributes in Forage Samples
Animal Feed Science and Technology Feb 2010 157(3-4), 139-150 (Full)
Wet chemistry v NIR
Wet chemistry used for forage analysis of ESC and WSC includes colorimetric phenol-sulphuric acid assay.
Kramer KJ, Kagan IA, Lawrence LM, Smith SR
Ethanol-soluble carbohydrates of cool-season grasses: prediction of concentration by near-infrared reflectance spectroscopy (NIRS) and evaluation of effects of cultivar and management
JEVS published online 19 February 2021 https://doi.org/10.1016/j.jevs.2021.103421
Prince K, Goff B, Lawrence L, Kagan I, Smith R.
Predicting water-soluble carbohydrates and ethanol-soluble carbohydrates in cool-season grasses with near-infrared reflectance spectroscopy.
American Forage and Grassland Council Conference Proceedings 2016. Pg 1.
The above papers (Prince 2016 and Kramer 2021 are linked to:
Prince, Kelly Joan MSc thesis 2017 University of Kentucky
Evaluating nonstructural carbohydrate variation of cool-season grasses based on genotype, management and environment
NSC in grass
Kramer KJ, Kagan IA, Lawrence LM, Smith SR
Ethanol-soluble carbohydrates of cool-season grasses: prediction of concentration by near-infrared reflectance spectroscopy (NIRS) and evaluation of effects of cultivar and management
JEVS published online 19 February 2021 https://doi.org/10.1016/j.jevs.2021.103421
Kramer KJ, Kagan IA, Lawrence LM, Goff BM, Smith SR
Water-soluble carbohydrates of cool-season grasses: prediction of concentrations by near-infrared reflectance spectroscopy (NIRS) and evaluation of effects of genetics, management and environment
JEVS published online April 2020. https://doi.org/10.1016/j.jevs.2020.103014
Linked to: Evaluating nonstructural carbohydrate variation of cool-season grasses based on genotype, management and environment
Jaqueth AL, Turner TR, Iwaniuk ME, McIntosh BJ, Burk AO
Relative traffic tolerance of cool-season turfgrasses and suitability for grazing by equine
Journal of Equine Veterinary Science published online 25 April 2019 https://doi.org/10.1016/j.jevs.2019.04.005
See also:
Jaqueth, Aubrey Lowrey
Novel uses of turfgrasses for equine operations
PhD dissertation, University of Maryland, 2018
Use of novel forages on horse farms: Novel turfgrass research update - Aubrey Jaqueth University of Maryland, March 2018
DeBoer ML, Hathaway MR, Kuhle KJ, Weber PSD, Reiter AS, Sheaffer CC, Wells MS, Martinson KL
Glucose and Insulin Response of Horses Grazing Alfalfa, Perennial Cool-Season Grass, and Teff Across Seasons
Journal of Equine Veterinary Science Volume 68, September 2018, Pages 33-38
Siciliano PD, Gill JC, Bowman MA
Effect of Sward Height on Pasture Nonstructural Carbohydrate Concentrations and Blood Glucose/Insulin Profiles in Grazing Horses
JEVS October 2017 vol 57, Pages 29–34
"decreasing the sward height by mowing pasture decreased NSC, WSC, and ESC concentrations and subsequently decreased the postprandial insulin response of horses grazing the pasture."
Saastamoinen M, Herzon I, Särkijärvi S, Schreurs C, Myllymäki M
Horse Welfare and Natural Values on Semi-Natural and Extensive Pastures in Finland: Synergies and Trade-Offs
Land 2017, 6, 69
Richards N, Bailey SR, McGilchrist P
Seasonal variation in non-structural carbohydrates in pastures grazed by Australian Thoroughbreds
Presented at the 8th European Workshop for Equine Nutrition June 2016 held in France.
The graphs below represent mean values of 351 pasture samples collected throughout the year from Feb 2011 until Sept 2015 from 220 paddocks in the Hunter Valley, NSW, Australia, a Thoroughbred breeding area. The samples were dried and sent to Equi-Analytical, for NIR analysis. Laminitis in grazing Thoroughbred broodmares was reported to be a significant issue in this area, with the highest incidence of laminitis in the spring. The paper concludes "Of considerable interest is the fact that the only major difference between winter and spring was in the WSC content, suggesting spring pastures are significantly higher in fructan."
TLS comment:
Sugar+starch combined (hydrolyzable sugars) are greater than 10% (the limit suggested by the ECIR group) in the spring and winter - half the samples would be above the average shown in the graphs.
Spring grass will be low in fibre, so horses are likely to and able to eat more. Research in cows found a correlation between volume ingested and high simple sugar levels (see Mayland et al 2000 below).
In-foal mares may be subject to gestational insulin resistance.
Fructan may be higher in spring than in winter, but the % of fructan is low compared to ESC, and ESC+starch.
The higher incidence of laminitis in the spring is likely to be the result of increased insulin resistance due to pregnancy, combined with the high level of hydrolyzable sugar+starch and possibly increased intake of grass in its vegetative, rather than mature, stage of growth.
Seasonal variation in non-structural carbohydrates in pastures grazed by Australian Thoroughbreds
Presented at the 8th European Workshop for Equine Nutrition June 2016 held in France.
The graphs below represent mean values of 351 pasture samples collected throughout the year from Feb 2011 until Sept 2015 from 220 paddocks in the Hunter Valley, NSW, Australia, a Thoroughbred breeding area. The samples were dried and sent to Equi-Analytical, for NIR analysis. Laminitis in grazing Thoroughbred broodmares was reported to be a significant issue in this area, with the highest incidence of laminitis in the spring. The paper concludes "Of considerable interest is the fact that the only major difference between winter and spring was in the WSC content, suggesting spring pastures are significantly higher in fructan."
TLS comment:
Sugar+starch combined (hydrolyzable sugars) are greater than 10% (the limit suggested by the ECIR group) in the spring and winter - half the samples would be above the average shown in the graphs.
Spring grass will be low in fibre, so horses are likely to and able to eat more. Research in cows found a correlation between volume ingested and high simple sugar levels (see Mayland et al 2000 below).
In-foal mares may be subject to gestational insulin resistance.
Fructan may be higher in spring than in winter, but the % of fructan is low compared to ESC, and ESC+starch.
The higher incidence of laminitis in the spring is likely to be the result of increased insulin resistance due to pregnancy, combined with the high level of hydrolyzable sugar+starch and possibly increased intake of grass in its vegetative, rather than mature, stage of growth.
Note that ESC appears to be the dominant influence on WSC and NSC.
The grass contains far more sugar+starch than fructan at all times of the year.
To try to give these levels of sugar and fructan some perspective in relation to laminitis risk, we hypothetically took the median previously laminitic (therefore insulin dysregulated) pony from research by Borer et al 2012, and put it on Richards' grass in the spring (the pasture with the highest NSC), eating 2.5% of his bodyweight per day, which should reflect some gorging on lush, sweet spring grass.
In the graph below:
Dark blue is the amount of fructan in grams he would eat per day on Richards' spring pasture - 5.2% DM x (289 kg x 2.5%).
Turquoise represents the amount of inulin fructan for his bodyweight that was given in a bolus experimentally to induce laminitis in 100% of horses - 7.5 g x 298 kg.
Light blue represents the amount of inulin fructan for his bodyweight that was given in a bolus experimentally to induce laminitis in 5/16 horses - 5 g x 298 kg. This is the lowest amount of fructan that has induced laminitis (in only some horses) experimentally.
Orange is the amount of ESC (simple sugars) and starch he would eat per day on Richards' spring pasture - 9.9% DM ESC plus 1.5% DM starch x (289 kg x 2.5%).
Compare this to this pony's results from Borer et al 2012:
Hashed orange is the maximum ESC plus starch he ate in his experimental meal of 500 g Happy Hoof (10% WSC plus 4% starch - ESC not given), plus 1 g/kg bw glucose = 70 g (500 g x 14%) plus 289 g = 359 g ESC plus starch (which was mostly glucose).
Pink is his peak insulin result following the Happy Hoof and 1g/kg bw glucose meal, in the spring.
Mauve is his peak insulin result following the Happy Hoof and 1g/kg bw glucose meal, in the autumn, for comparison. Horses may be more insulin resistant in the autumn, perhaps to help them put on weight for the winter.
In the graph below:
Dark blue is the amount of fructan in grams he would eat per day on Richards' spring pasture - 5.2% DM x (289 kg x 2.5%).
Turquoise represents the amount of inulin fructan for his bodyweight that was given in a bolus experimentally to induce laminitis in 100% of horses - 7.5 g x 298 kg.
Light blue represents the amount of inulin fructan for his bodyweight that was given in a bolus experimentally to induce laminitis in 5/16 horses - 5 g x 298 kg. This is the lowest amount of fructan that has induced laminitis (in only some horses) experimentally.
Orange is the amount of ESC (simple sugars) and starch he would eat per day on Richards' spring pasture - 9.9% DM ESC plus 1.5% DM starch x (289 kg x 2.5%).
Compare this to this pony's results from Borer et al 2012:
Hashed orange is the maximum ESC plus starch he ate in his experimental meal of 500 g Happy Hoof (10% WSC plus 4% starch - ESC not given), plus 1 g/kg bw glucose = 70 g (500 g x 14%) plus 289 g = 359 g ESC plus starch (which was mostly glucose).
Pink is his peak insulin result following the Happy Hoof and 1g/kg bw glucose meal, in the spring.
Mauve is his peak insulin result following the Happy Hoof and 1g/kg bw glucose meal, in the autumn, for comparison. Horses may be more insulin resistant in the autumn, perhaps to help them put on weight for the winter.
Obviously, this is far from being a perfect comparison - apart from being hypothetical, there's likely to be little value in comparing natural grazing of fructan and sugar+starch over 24 hours with nasogastric bolus or bucket administration, but researchers have been using the nasogastric bolus administration of fructan as a potential model for naturally ingested fructan for years, so we would suggest our model is just as good!
As you can see, even with our pony eating 2.5% of his bodyweight in spring grass per day, the fructan levels he's eating don't come anywhere near the amount of inulin (a short-chain fructan) given in one bolus by nasogastric tube, even at the lower rate of 5 g/kg bodyweight that caused laminitis in only 5 out of 16 horses experimentally.
However, the amount of simple sugars (ESC) and starch he eats per day is more than double that which, when given in a single bucket feed, caused insulin to rise to over 500 uIU/ml in the spring, and nearly 1000 uIU/ml in the autumn. The minimum level of insulin that causes laminitis isn't known, but Melody de Laat found lamellar pathology in all horses that had experimentally induced insulin levels of around 200 uIU/ml for 48 hours, and Walsh et al 2009 found that the onset of laminitis was associated with hyperinsulinaemia > 100 uIU/ml.
As you can see, even with our pony eating 2.5% of his bodyweight in spring grass per day, the fructan levels he's eating don't come anywhere near the amount of inulin (a short-chain fructan) given in one bolus by nasogastric tube, even at the lower rate of 5 g/kg bodyweight that caused laminitis in only 5 out of 16 horses experimentally.
However, the amount of simple sugars (ESC) and starch he eats per day is more than double that which, when given in a single bucket feed, caused insulin to rise to over 500 uIU/ml in the spring, and nearly 1000 uIU/ml in the autumn. The minimum level of insulin that causes laminitis isn't known, but Melody de Laat found lamellar pathology in all horses that had experimentally induced insulin levels of around 200 uIU/ml for 48 hours, and Walsh et al 2009 found that the onset of laminitis was associated with hyperinsulinaemia > 100 uIU/ml.
Kagan IA, Lawrence LM, Seman DH, Prince KJ, Fowler AL, Smith SR
Effects of sampling time, cultivar, and methodology on water- and ethanol-soluble carbohydrate profiles of three cool-season grasses in central Kentucky
JEVS published online Nov 2017
See also
Prince, Kelly Joan MSc thesis University of Kentucky 2017
Evaluating nonstructural carbohydrate variation of cool-season grasses based on genotype, management and environment
Effects of sampling time, cultivar, and methodology on water- and ethanol-soluble carbohydrate profiles of three cool-season grasses in central Kentucky
JEVS published online Nov 2017
See also
Prince, Kelly Joan MSc thesis University of Kentucky 2017
Evaluating nonstructural carbohydrate variation of cool-season grasses based on genotype, management and environment
Akers, Morgan N 2009 MSc thesis
Effects of Early Spring Growth Annual Ryegrass Pasture Consumption on Parameters Associated with Laminitis in Horses
Nonstructural Carbohydrates in Cool-season Grasses - Special Report 1079-E November 2007 Oregon State University
NSC in cool-season grasses varied significantly between varieties, species, between morning to afternoon and at different times of the year. In the table below (Table 1) the highest average NSC concentrations were found in ryegrass species. Matua is a prairie grass. Barfest is a festolium. The bottom 4 grasses are orchard grasses.
In the graph below (Figure 4), 4 cool-season perennial ryegrass varieties were harvested in the vegetative state at 9 am and 8 pm. Samples were freeze-dried and analysed by Dairy One. NSC was significantly higher in the afternoon in the "high NSC" varieties of ryegrass.
Effects of Early Spring Growth Annual Ryegrass Pasture Consumption on Parameters Associated with Laminitis in Horses
Nonstructural Carbohydrates in Cool-season Grasses - Special Report 1079-E November 2007 Oregon State University
NSC in cool-season grasses varied significantly between varieties, species, between morning to afternoon and at different times of the year. In the table below (Table 1) the highest average NSC concentrations were found in ryegrass species. Matua is a prairie grass. Barfest is a festolium. The bottom 4 grasses are orchard grasses.
In the graph below (Figure 4), 4 cool-season perennial ryegrass varieties were harvested in the vegetative state at 9 am and 8 pm. Samples were freeze-dried and analysed by Dairy One. NSC was significantly higher in the afternoon in the "high NSC" varieties of ryegrass.
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McIntosh Bridgett PhD dissertation December 2006
Circadian and Seasonal Variation in Pasture Nonstructural Carbohydrates and the Physiological Response of Grazing Horses
Allen EM, Meyer WA, Ralston SL
Variability in protein and mineral content of pasture and turfgrasses
2004 Rutgers Turfgrass Proceedings (and in Pferdeheilkunde 2005; 21: 11-12)
Volaire F, Norton MR, Norton GM, Lelièvre F
Seasonal patterns of growth, dehydrins and water-soluble carbohydrates in genotypes of Dactylis glomerata varying in summer dormancy
Ann Bot. 2005 May;95(6):981-90. Epub 2005 Mar 10 (PubMed)
Gives figures for monosaccharides, sucrose & fructans as well as WSC total.
De Souza A, Sandrin CZ, Moraes MG, Figueiredo-Ribeiro RL
Diurnal variations of non-structural carbohydrates in vegetative tissues of Melinis minutiflora, Echinolaena inflexa and Lolium multiflorum
(Poaceae)
Revista Brasil. Bot., V.28, n.4, p.755-763, out.-dez. 2005
McGrath D
Seasonal Variation in the Water-Soluble Carbohydrates of Perennial and Italian Ryegrass under Cutting Conditions
Irish Journal of Agricultural Research 1988 27: 131-139
NSC in cereal grasses
Chatterton NJ, Watts KA, Jensen KB, Harrison PA, Horton WH
Nonstructural Carbohydrates in Oat Forage
The Journal of Nutrition, Volume 136, Issue 7, 1 July 2006, Pages 2111S–2113S. https://doi.org/10.1093/jn/136.7.2111S
J Anim Physiol Anim Nutr (Berl). 2012 Jun;96(3):428-35. doi: 10.1111/j.1439-0396.2011.01159.x. Epub 2011 May 16. (PubMed)
Effects of high and moderate non-structural carbohydrate hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings.
Shepherd ML, Pleasant RS, Crisman MV, Werre SR, Milton SC, Swecker WS Jr.
"The objective of this study was to determine the effects of high and moderate non-structural carbohydrates (NSC) hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings. Eight adult overweight (average BCS 7 [9-point scale]) Arabian geldings were fed each of two orchardgrass hays, high NSC (18% DM) and moderate NSC (12% DM), in a cross over design during two 28-day periods. Body weight and body condition score assessment along with blood sampling to measure insulin, glucose, leptin, and triglyceride concentrations were performed on days 0, 7, 14, 21 and 28 of each period. Effects of hay, period, day, and day*hay on plasma glucose and serum leptin were not detected. Serum insulin was influenced by hay (p = 0.001), day (p = 0.03), and day*hay (p = 0.04). Insulin concentrations were higher on day 7 in the high NSC group (15.6 μIU/ml) than the moderate NSC group (9.5 μIU/ml), but not by day 14 (p = 0.0007). Plasma triglyceride was influenced by period (p = 0.0003), day*period (p < 0.0001), and day*hay (p = 0.02). Hyperinsulinaemia was not observed in the overweight Arabian geldings fed either a moderate or high NSC hay."
The horses presumably weren't insulin resistant (insulin 15.6 and 9.5 uIU/ml).
Effects of high and moderate non-structural carbohydrate hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings.
Shepherd ML, Pleasant RS, Crisman MV, Werre SR, Milton SC, Swecker WS Jr.
"The objective of this study was to determine the effects of high and moderate non-structural carbohydrates (NSC) hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings. Eight adult overweight (average BCS 7 [9-point scale]) Arabian geldings were fed each of two orchardgrass hays, high NSC (18% DM) and moderate NSC (12% DM), in a cross over design during two 28-day periods. Body weight and body condition score assessment along with blood sampling to measure insulin, glucose, leptin, and triglyceride concentrations were performed on days 0, 7, 14, 21 and 28 of each period. Effects of hay, period, day, and day*hay on plasma glucose and serum leptin were not detected. Serum insulin was influenced by hay (p = 0.001), day (p = 0.03), and day*hay (p = 0.04). Insulin concentrations were higher on day 7 in the high NSC group (15.6 μIU/ml) than the moderate NSC group (9.5 μIU/ml), but not by day 14 (p = 0.0007). Plasma triglyceride was influenced by period (p = 0.0003), day*period (p < 0.0001), and day*hay (p = 0.02). Hyperinsulinaemia was not observed in the overweight Arabian geldings fed either a moderate or high NSC hay."
The horses presumably weren't insulin resistant (insulin 15.6 and 9.5 uIU/ml).
Hay or haylage for horses: a comparison
Johanna Besier, Brigitte Strickler, Ruedi von Niederhäusern and Ueli Wyss
Johanna Besier, Brigitte Strickler, Ruedi von Niederhäusern and Ueli Wyss
Nonstructural Carbohydrates in Cool-season Grasses
Troy Downing and Mike Gamroth, Oregon State University Extension Service Special Report 1079-E November 2007
"Plants accumulate sugars during the day and use them up at night".
Fisher DS, Mayland HF, Bums JC
Variation in ruminant's preference for tall fescue hays cut either at sundown or at sunup
J. Anim. Sci. 77:762-768 1999
found the highest concentrations of NSC in forages cut late in the afternoon.
Troy Downing and Mike Gamroth, Oregon State University Extension Service Special Report 1079-E November 2007
"Plants accumulate sugars during the day and use them up at night".
Fisher DS, Mayland HF, Bums JC
Variation in ruminant's preference for tall fescue hays cut either at sundown or at sunup
J. Anim. Sci. 77:762-768 1999
found the highest concentrations of NSC in forages cut late in the afternoon.
Henry F. Mayland, Glenn E. Shewmaker, Philip A. Harrison, and N. Jerry Chatterton
Nonstructural Carbohydrates in Tall Fescue Cultivars: Relationship to Animal Preference
Agronomy Journal Vol 92 Nov-Dec 2000
8 Tall Fescue cultivars, grown in Kimberley, Idaho, 42'30 N, 114'08 W, elevation 1200 m, were sampled between 8 and 9.30 am in 4 months during the growing season over 2 years. The grass was vegatively growing, samples were cut at 8 cm. The grass was topped to 8 cm and fertilized between samplings. NSC included starch, fructan, glucose, fructose, sucrose and other non-quantified soluble sugars.
Total NSC ranged from 91 to 162 g/kg the first year and 68 to 192 g/kg the second year, with the lowest NSC recorded in August each year, when regrowth was slowest.
The total NSC component averages (mean) over the 2 years were (as structural dry mass (SDM) and dry matter (DM) in g/kg:
SDM DM
Glucose 14 12.6
Fuctose 5 3.6
Sucrose 40 34.8 Total measured sugars (glucose, fructose, sucrose) on a DM basis were 51 g/kg
Fructan 23 20.9
Starch 24 20.9
Other sugars 23 19.2
Total NSC 129 112.0
Sucrose was the primary component of NSC. Monosaccharides and disaccharides accounted for an average of around 45% of NSC, with a range of 33 to 58%.
Cows were given free access to the different grasses and grazed the grasses with the highest NSC, and highest monosaccharides and disaccharides, the most, and in general grazed the grasses with the lowest NSC the least.
Nonstructural Carbohydrates in Tall Fescue Cultivars: Relationship to Animal Preference
Agronomy Journal Vol 92 Nov-Dec 2000
8 Tall Fescue cultivars, grown in Kimberley, Idaho, 42'30 N, 114'08 W, elevation 1200 m, were sampled between 8 and 9.30 am in 4 months during the growing season over 2 years. The grass was vegatively growing, samples were cut at 8 cm. The grass was topped to 8 cm and fertilized between samplings. NSC included starch, fructan, glucose, fructose, sucrose and other non-quantified soluble sugars.
Total NSC ranged from 91 to 162 g/kg the first year and 68 to 192 g/kg the second year, with the lowest NSC recorded in August each year, when regrowth was slowest.
The total NSC component averages (mean) over the 2 years were (as structural dry mass (SDM) and dry matter (DM) in g/kg:
SDM DM
Glucose 14 12.6
Fuctose 5 3.6
Sucrose 40 34.8 Total measured sugars (glucose, fructose, sucrose) on a DM basis were 51 g/kg
Fructan 23 20.9
Starch 24 20.9
Other sugars 23 19.2
Total NSC 129 112.0
Sucrose was the primary component of NSC. Monosaccharides and disaccharides accounted for an average of around 45% of NSC, with a range of 33 to 58%.
Cows were given free access to the different grasses and grazed the grasses with the highest NSC, and highest monosaccharides and disaccharides, the most, and in general grazed the grasses with the lowest NSC the least.
NSC in hay
Moore-Colyer MJS, Taylor JLE, James R
The Effect of Steaming and Soaking on the Respirable Particle, Bacteria, Mould, and Nutrient Content in Hay for Horses
JEVS April 2016 Volume 39, Pages 62–68
Deepdyve
Samples taken from 30 small bales from a range of meadow (permanent pasture, several grass species) and seed (perennial rye grass) hays collected from all over the UK and considered representative of the UK hay harvest in 2009
had mean WSC of 12.6% on an as fed basis (range 6.2% - 20.2%), measured by the phenol-sulfuric method (Dubois et al. 1956). Estimating a DM content of 88%, this would be 11.09 % WSC on a DM basis. Starch, ESC, DE, DM not given.
Müller CE, Nostell K, Bröjer J
Methods for reduction of water soluble carbohydrate content in grass forages for horses
Livestock Science Volume 186, April 2016, Pages 46-52
The effect of 1. conservation method (hay, haylage, silage); 2. using bacterial inoculants (in haylage and silage); 3. storage time; and 4. soaking was measured on WSC.
WSC was the sum of glucose, fructose, sucrose and fructans were analysed using an enzymatic-spectrophotomectric method.
Grass was harvested as silage @ 40% DM, haylage @ 60% DM and hay @ 84% DM. Silage had lower glucose, fructose and WSC than haylage and hay; hay had more sucrose and fructans than silage and haylage.
Forages were sampled after 3, 6, 12 and 18 months storage - length of storage time did not affect WSC.
Forages were soaked for 12 and 24 hours in water. Soaking for 12 hours reduced fructose and WSC in silage by ~50%. Soaking for 12 hours reduced glucose, fructose and WSC in haylage by ~50%, no further losses occurred after soaking for 24 hours. Soaking for 12 hours reduced glucose by 50%, fructose by 30%, sucrose by 85% and fructan by 60% in hay, with further losses of glucose after soaking for 24 hours.
WSC was 24 g/kg DM in silage before soaking, and 38 g/kg DM in hay after soaking for 24 hours.
NSC in haylage
Harris PA, Nelson S, Carslake HB, Argo Caroline McG, Wolf R, Fabri B, Brolsma KM, van Oostrum MJ, Ellis AD
Comparison of NIRS and Wet Chemistry Methods for the Nutritional Analysis of Haylages for Horses
Journal of Equine Veterinary Science published online 4 September 2018
Lindåse S, Müller C, Nostell K, Bröjer J
Evaluation of glucose and insulin response to haylage diets with different content of nonstructural carbohydrates in 2 breeds of horses
Domest Anim Endocrinol. 2018 Jul;64:49-58. doi: 10.1016/j.domaniend.2018.03.006. Epub 2018 Apr 9
Harris PA, Nelson S, Carslake HB, Argo Caroline McG, Wolf R, Fabri B, Brolsma KM, van Oostrum MJ, Ellis AD
Comparison of NIRS and Wet Chemistry Methods for the Nutritional Analysis of Haylages for Horses
Journal of Equine Veterinary Science published online 4 September 2018
Lindåse S, Müller C, Nostell K, Bröjer J
Evaluation of glucose and insulin response to haylage diets with different content of nonstructural carbohydrates in 2 breeds of horses
Domest Anim Endocrinol. 2018 Jul;64:49-58. doi: 10.1016/j.domaniend.2018.03.006. Epub 2018 Apr 9
General information about grass
Dairy Grazing: Growth of Pasture Plants - University of Missouri
Green plants photosynthesis in their chloroplasts, making simple sugars or carbohydrates from light energy from sunlight, carbon dioxide in the air and water in the soil, and releasing oxygen. Young leaves are more efficient at photosynthesis than old leaves, leaves in high intensity light are more efficient than leaves in shade. Cool-season = temperate = C3 plants. The optimal temperature for C3 grass growth is 18 - 24 degrees C. C3 plants need water and are most productive during cooler moister spring and autumn months. C3 grasses grow in the spring, mature by late spring or early summer, become semidormant in the summer and resume growth in the autumn.
Dairy Grazing: Growth of Pasture Plants - University of Missouri
Green plants photosynthesis in their chloroplasts, making simple sugars or carbohydrates from light energy from sunlight, carbon dioxide in the air and water in the soil, and releasing oxygen. Young leaves are more efficient at photosynthesis than old leaves, leaves in high intensity light are more efficient than leaves in shade. Cool-season = temperate = C3 plants. The optimal temperature for C3 grass growth is 18 - 24 degrees C. C3 plants need water and are most productive during cooler moister spring and autumn months. C3 grasses grow in the spring, mature by late spring or early summer, become semidormant in the summer and resume growth in the autumn.