Microbial activity in grass-fed in-vitro continuous cultures in response to infusion of graded levels of soluble sugars

2001 ◽  
Vol 2001 ◽  
pp. 29-29
Author(s):  
M.R.F. Lee ◽  
D.K. Leemans ◽  
D.R. Davies ◽  
R.J. Merry ◽  
J. M. Moorby ◽  
...  
Keyword(s):  
Microbial Population ◽  
Soluble Sugars ◽  
Nitrogen Supply ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Microbial Protein ◽  
Continuous Cultures ◽  
Water Soluble Carbohydrate ◽  
N Use

Novel lines of high sugar ryegrass have been shown to increase the efficiency of N use and milk production in zero-grazed cattle (Miller et al., 1999). An experiment was carried out to determine whether this was in part due to an increase in the efficiency of microbial protein synthesis in response to the amount and availability of water soluble carbohydrate (WSC) increasing the balance between energy and nitrogen supply to the rumen microbial population.

The impact of hexose partitioning in sheep in vivo

2001 ◽  
Vol 2001 ◽  
pp. 157-157 ◽  
Author(s):  
A. R. Moss ◽  
C. J. Newbold ◽  
D.I. Givens
Keyword(s):  
Methane Production ◽  
Short Chain Fatty Acids ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Carbohydrate Source ◽  
Fermentation Products ◽  
Water Soluble Carbohydrate ◽  
The Impact

Methane production represents an important sink for hydrogen within the rumen Beever (1993) suggested that the partitioning of fermentable dry matter (DM) between microbial synthesis and fermentation products would alter the pattern of hydrogen production and hence methanogenesis. This hypothesis was investigated in vitro using a range of diets varying in carbohydrate source (Moss et al., 2000). Methane production (moles) increased as the proportion of DM fermented to short chain fatty acids (SCFA) increased and this was related to decreasing water soluble carbohydrate (WSC) to cell wall (NDF) ratio of the diet. The objectives of the current study was to design diets with a range of WSC:NDF ratios and to measure the impact on hexose partitioning and methane production in sheep in vivo.

Effect of spraytopping applications of paraquat and glyphosate on the nutritive value and regeneration of vulpia (Vulpia bromoides (L.) S.F. Gray)

1991 ◽  
Vol 42 (8) ◽  
pp. 1405 ◽  
Author(s):  
AR Leys ◽  
BR Cullis ◽  
B Plater
Keyword(s):  
Nutritive Value ◽  
Grain Filling ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Wagga Wagga ◽  
Time Of Application ◽  
Water Soluble Carbohydrate ◽  
Subsequent Regeneration ◽  
Earlier Application

The effects of paraquat and glyphosate on the nutritive value of dry residues of vulpia [Vulpia bromoides (L.) S. F. Gray], and its subsequent regeneration the following year were examined at Wagga Wagga during the spring, summer and winter of 1986/87 and 1987/88. Paraquat (100 and 200 g a.i./ha) and glyphosate (135 and 270 g a.i./ha) were applied as spraytopping treatments at heading, anthesis and early grain filling stages of vulpia. For both herbicides, time of application was critical to the level of regeneration obtained. Glyphosate gave 84 and 83% control when applied at heading and anthesis respectively, delaying application until early grain filling reduced the level of vulpia control to 28%. Paraquat gave 81% control when applied at anthesis, while delaying application until early grain filling, or earlier application at heading, gave 59% control. Crude protein (CP) and water-soluble carbohydrate (WSC) concentrations, and in vitro organic matter digestibilities (OMD) were measured in vulpia residues collected for 16 weeks after herbicide application. Paraquat increased CP levels most when applied at heading (from 4-8 to 7.2% in 1986, and from 4.9 to 6.5% in 1987). Glyphosate increased CP levels most when applied at heading in 1986 (from 4.8 to 5.4%), but at anthesis in 1987 (from 4.9 to 6.5%). Glyphosate increased WSC most when applied at heading (from 5.7 to 10.6% in 1986, and from 3.5 to 6.3% in 19871, while paraquat reduced WSC in both years. Application of glyphosate at heading was the only treatment to increase OMD (from 50.5 to 54.7%).

Increased intake responses from beef steers zero-grazed on Lolium perenne selected for high levels of water soluble carbohydrate

2001 ◽  
Vol 2001 ◽  
pp. 86-86
Author(s):  
M.R.F. Lee ◽  
R.T. Evans ◽  
J.M. Moorby ◽  
M.O. Humphreys ◽  
M. K. Theodorou ◽  
...  
Keyword(s):  
Lolium Perenne ◽  
Microbial Population ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Beef Steers ◽  
Protein Nitrogen ◽  
Dietary Nitrogen ◽  
Available Energy ◽  
Low Levels ◽  
Water Soluble Carbohydrate

Fresh forages may result in the loss of up to 40% of dietary nitrogen as rumen ammonia, as the microbial population is unable to utilise all the non-protein nitrogen released from rapidly degradable plant proteins. This may be due to the characteristically low levels of readily available energy released in the rumen, primarily as a result of the low levels of water soluble carbohydrate (WSC) in traditional forages. In a previous experiment Lee et al, (1999) found an increase in liveweight gain of pre-weaned lambs grazing Lolium perenne selected for high WSC concentrations. This study examined whether the enhanced performance on high WSC grass may be related to increased supply of nitrogen to the small intestine.

Diet selection by sheep grazing Phalaris aquatica L. pastures of differing water-soluble carbohydrate content

2000 ◽  
Vol 51 (6) ◽  
pp. 757 ◽  
Author(s):  
T. A. Ciavarella ◽  
H. Dove ◽  
B. J. Leury ◽  
R. J. Simpson
Keyword(s):  
Diet Selection ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Short Term ◽  
Phalaris Aquatica ◽  
Fibre Concentration ◽  
Water Soluble Carbohydrate ◽  
Reporting Data ◽  
Selection Of

A short-term shading treatment was used to create a Phalaris aquatica L. pasture with alternating strips of ‘low’ [62 mg/g dry matter (DM)] and ‘high’ (126 mg/g DM) water-soluble carbohydrate (WSC) concentration. Analyses showed that starch and all components of the WSC were reduced in concentration by shading. The shaded and unshaded pasture strips did not differ significantly in in vitro DM digestibility (84% DM), nitrogen (3.1% DM), or neutral detergent fibre concentration (42.4% DM). Synthetic alkanes were applied to the pasture strips as markers to measure the selection of the shaded and unshaded pasture by sheep. When 12–13-month-old Merino wethers were given simultaneous access to both pasture treatments, they selected 2.6-fold more unshaded (high WSC) pasture than shaded pasture. The results indicate the involvement of herbage total WSC and its components in the process of diet selection by sheep, and suggest that in future studies, more attention should be paid to reporting data for total WSC concentration.

INFLUENCE OF WATER-SOLUBLE CARBOHYDRATE AND CRUDE PROTEIN CONTENT ON IN VITRO DIGESTION OF DRY MATTER IN HIGHLY DIGESTIBLE FORAGES

1972 ◽  
Vol 52 (2) ◽  
pp. 151-156
Author(s):  
D. M. Bowden
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Cumulative Effect ◽  
In Vitro Digestion ◽  
Water Soluble ◽  
Soluble Carbohydrate ◽  
Freeze Dried ◽  
Influence Of Water ◽  
Water Soluble Carbohydrate

Freeze-dried samples from six series of harvests of orchardgrass (Dactylis glomerata L.) and two series of grass–legume mixtures were generally highly digestible with high levels of water-soluble carbohydrate (WSC). When WSC content was held constant, the influence of crude protein (CP) content on dry matter digested in vitro was statistically significant in 6 of the 19 cuts of orchardgrass and 1 of the 15 cuts of grass–legume mixtures. When CP was held constant, the influence of WSC content on dry matter digested in vitro was significant in seven cuts of orchardgrass and seven cuts of grass–legume. CP content had a greater effect than WSC content on dry matter digested in vitro in 10 cuts of orchardgrass and six cuts of grass–legume mixtures. Cumulative effect of CP and WSC content on in vitro dry matter digestion varied between cuts. The potential of CP and WSC content alone or together as predictors of digestibility of the highly digestible forages sampled in this study varied between cuts.

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