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Full-Text Articles in Physical Sciences and Mathematics

Forage Production In Alternative Agriculture: Dairy Farms In Eastern Canada, G Allard, M Mauries, D Pellerin Jun 2024

Forage Production In Alternative Agriculture: Dairy Farms In Eastern Canada, G Allard, M Mauries, D Pellerin

IGC Proceedings (1993-2023)

Alternative agriculture has been adopted by dairy farmers in response to concerns over conventional agriculture. The purpose of this study is to compare forage production characteristics on 12 alternative or conventional dairy farms. Yields and quality components were determined for the first and the second cuts of forage harvested in 1994 and 1995. Similar yields as well as similar crude protein and ADF concentrations were obtained for forages produced on alternative and conventional farms. Although potassium concentrations were lower under alternative farming, forage production is not a limiting factor in alternative dairy farming.


Effects Of Color Of Facilities On Evaluation Of Farm Landscape, Y Hosokawa, K Toda Jun 2024

Effects Of Color Of Facilities On Evaluation Of Farm Landscape, Y Hosokawa, K Toda

IGC Proceedings (1993-2023)

The objective of this study was to make clear the color of farm facilities, being harmonious with the landscape. For the color design of farm facility, the questionnaire was given to 429 subjects by the 8-ordered choices from each figure painted 8 colors, i.e., red, yellow­ red, yellow, green, blue, purple, white, and black, in each landscape element of the roof of barn, the board of fence, the steel tower and the plastic-pack of silos by using the image processor. The harmonious color chosen were red in the roof of barn and mostly white in both fence, steel tower silo, …


Rhizobial And Nutritional Responses Of Desmanthus Clay Soils Of Queensland, N J. Brandon, R A. Date, R M. Jones, R L. Clem, G A. Bahnisch, P R. Spies, A Becerra, B A. Robertson, T.W G. Graham Jun 2024

Rhizobial And Nutritional Responses Of Desmanthus Clay Soils Of Queensland, N J. Brandon, R A. Date, R M. Jones, R L. Clem, G A. Bahnisch, P R. Spies, A Becerra, B A. Robertson, T.W G. Graham

IGC Proceedings (1993-2023)

The objective of these studies was to determine the reasons for chlorosis of desmanthus observed at some sites in southeast Queensland. Inoculation with Rhizobium increased growth of desmanthus in 2 of 4 soils in the field and 4 of 8 soils in pots. Greatest responses occurred in soils with few or no effective native Rhizobium. Most soils however, contained native strains that were effective. Omission of sulphur significantly reduced dry weight of desmanthus grown in pots in 5 of 7 soils by 30-51% relative to plants supplied with all nutrients. Omission of P and Mo resulted in similar yield reductions …


Biological Nitrogen Fixation In A Grass-Clover Pasture Grazed By Dairy Cows, F P. Vinther, K Søegaard, O Aaes Jun 2024

Biological Nitrogen Fixation In A Grass-Clover Pasture Grazed By Dairy Cows, F P. Vinther, K Søegaard, O Aaes

IGC Proceedings (1993-2023)

The objective of this study was to estimate the annual input of nitrogen through biological nitrogen fixation (BNF) to a grass-clover pasture (Lolium perenne L. - Trifolium repens L.) grazed by dairy cows. The input was estimated by combining measurements of BNF in non-grazed plots, BNF in urine affected plots and estimates of the proportion of the pasture affected by urine. Total BNF in non-grazed plot was 75 and 256 kg N ha-1 in 1994 and 1995, respectively. Urine affected BNF both by decreasing the proportion of clover and by decreasing the proportion of N derived from the atmosphere. The …


Phosphorus Requirements In Legumes: Calibration Of A Rapid And Simple Tissue Test, A Moron Jun 2024

Phosphorus Requirements In Legumes: Calibration Of A Rapid And Simple Tissue Test, A Moron

IGC Proceedings (1993-2023)

The objective of this research was to adjust and calibrate a phosphorus (P) tissue test to diagnose in a simple and rapid manner the nutritional status of commonly used legumes in Uruguay. Field experiments conducted during 1993-94 with four legumes, showed a significant yield response to increasing P fertilizer rates. A colorimetric sap analysis was used to determine P status in legumes. A strong relationship was found between P sap analysis and relative yields. A critical level of 90-100 μg P/ml in sap to attain 90% of the maximum yield was obtained.


Evaluation Of Different Nitrogen Sources On The Production And Chemical Properties Of C4-Sub-Tropic Pastures, J F. Reckling, G.H J. Kruger Jun 2024

Evaluation Of Different Nitrogen Sources On The Production And Chemical Properties Of C4-Sub-Tropic Pastures, J F. Reckling, G.H J. Kruger

IGC Proceedings (1993-2023)

Digitaria eriantha fertilised with limestone ammonium nitrate (LAN 28 % N), although not statistically significant, resulted in higher dry matter production in comparison to those plants fertilised with urea (U 46% N). Significant lower (P<0.05) soil calcium levels were found in plots fertilised with LAN. Plants fertilised with urea had double the amount of Aspartic and Glutamic acid, indicating that urea did not convert to NO3 -, but was taken up as ammonium.


Effect Of Nitrogen And Potash Fertilization On Dry Matter Yield And Mineral Composition Of Pangolagrass, J B. Andrade, C L. Justo, J.L. V. Coutinho, R M. Peres, E Ferrari Junior, V T. Paulino, W Henrique, J C. Werner, H B. Mattos Jun 2024

Effect Of Nitrogen And Potash Fertilization On Dry Matter Yield And Mineral Composition Of Pangolagrass, J B. Andrade, C L. Justo, J.L. V. Coutinho, R M. Peres, E Ferrari Junior, V T. Paulino, W Henrique, J C. Werner, H B. Mattos

IGC Proceedings (1993-2023)

The effect of nitrogen and potash fertilizations on dry matter and protein yields and chemical composition of pangolagrass (D. decumbens Stent.) was studied in a randomized block design with four replications using a 2 x 2 factorial arrangement. Nitrogen and potash were applied after each cut as an equivalent to 3 and 2% of dry matter (65°C) yield, respectively. There were great increases in dry matter and protein yields when nitrogen alone or combined with potash was used. Potash fertilization alone had no effect on the variables described above. Nitrogen fertilization improved forage pangolagrass composition, being particularly effective on crude …


Nitrogen In Stubble As A Limiting Factor Of Regrowth And Yield Of Orchardgrass After Cutting, T Matsunaka, T Ishii, M Jin Jun 2024

Nitrogen In Stubble As A Limiting Factor Of Regrowth And Yield Of Orchardgrass After Cutting, T Matsunaka, T Ishii, M Jin

IGC Proceedings (1993-2023)

Two field trials were carried out to reexamine the role of total nonstructural carbohydrates (TNC) and nitrogen (N) of the stubble in regrowth of orchardgrass (Dactylis Glomerata L.) during 10 days after cutting and the yield of next cutting. The regrowth and the yield were independent of TNC content in the stubble. They increased with N content in the stubble derived from the different rate of previous N application. When the TNC content in the stubble at the time of cutting was more than about 18% (dry matter basis), the regrowth even in a darkroom was not affected by …


Effect Of Nitrogen Fertilization Upon Spring Growth In Thinopyrum Poticum In Alkaline Soils. Argentina, R Fernandez Grecco, A Sciotti, A Mazzanti, H Echeverria Jun 2024

Effect Of Nitrogen Fertilization Upon Spring Growth In Thinopyrum Poticum In Alkaline Soils. Argentina, R Fernandez Grecco, A Sciotti, A Mazzanti, H Echeverria

IGC Proceedings (1993-2023)

Wheatgrass is a perennial forage grass adapted to low fertility alkaline soils in the Flooding pampa. It has an annual forage growth cycle characterised by a high spring-summer concentration and low values in winter. The objective of this study was to assess that it is possible to anticipate and increase forage growth and DM production of wheatgrass pastures applying nitrogen fertilization. The experiment was carried out at the Balcarce Experimental Station from 28/08/95 to 04/12/95. Using a completely randomized block design the effects of 6 levels of N: 0, 50, 100, 150, 200 and 250 kg Nha-1, added as NO3 …


Effect Of Nitrogen Fertilization Upon Winter Growth In Natural Pastures Of The South East Of Buenos Aires Province, Argentina, R C. Fernandez Grecco, A E. Mazzanti, H A. Echeverria Jun 2024

Effect Of Nitrogen Fertilization Upon Winter Growth In Natural Pastures Of The South East Of Buenos Aires Province, Argentina, R C. Fernandez Grecco, A E. Mazzanti, H A. Echeverria

IGC Proceedings (1993-2023)

The effect of winter nitrogen fertilization upon herbage accumulation during the winter-spring period on a natural pasture of the Flooding Pampa dominated by cool season annual (Lolium multiflorum) and perennial (Stipa neesiana) grasses was evaluated. The experiment was carried out from August to November in 1994 and 1995. Fertilization treatments were: 0, 50, 100, 150, 200 and 250 kgN ha- 1 (N0, N50, N100, N150, N200 and N250, respectively). The experimental plots were set out in three randomized blocks. In 1994, maximum forage accumulation was reached at N150, and no significant differences were found among N150, …


Effectivity Of Arbuscular Mycorrhizas In Sustainable Grassland Agriculture Following Conversion From Intensive Management, W R. Eason, J Scullion, E P. Scott Jun 2024

Effectivity Of Arbuscular Mycorrhizas In Sustainable Grassland Agriculture Following Conversion From Intensive Management, W R. Eason, J Scullion, E P. Scott

IGC Proceedings (1993-2023)

With increased interest in sustainable agriculture, attention has focused on the role of arbuscular mycorrhiza (AM) in the productivity of agricultural systems. AM spores were taken from grassland and grass-arable systems with either a history of high-input, conventional, or low-input, organic management, and used as a source of inoculum in host plants (Allium amelioprasum, Trifolium repens and Lolium perenne). Spores from organic management systems produced a greater yield response than those from conventional systems. Where various spore inoculum produced differences in host growth responses, it was observed that the infected root of these host plants also produced similar …


Buffelgrass Forage And Seed Production Responses To N And Fertilization, W R. Ocumpaugh, M A. Hussey, B L. Burson Jun 2024

Buffelgrass Forage And Seed Production Responses To N And Fertilization, W R. Ocumpaugh, M A. Hussey, B L. Burson

IGC Proceedings (1993-2023)

Forage and seed production responses to nitrogen (N) and phosphorus (P) fertilizer of Common buffelgrass (Cenchrus ciliaris L.) were evaluated for three years (1991-93). An incomplete factorial set of five rates of N and P were applied each year. Seed data were collected by hand stripping mature seed followed by a forage harvest. Seed quality characteristics were determined on each seed sample. No response to N fertilizer was observed in 1991 nor to P in any year. In 1992, there was a linear forage yield response to N fertilizer. In 1993, both the linear and quadratic effects of N …


Grassland Management In Central Area Of The Masurian Landscape Park, K Mlynarczyk, E Marks, E Korona Jun 2024

Grassland Management In Central Area Of The Masurian Landscape Park, K Mlynarczyk, E Marks, E Korona

IGC Proceedings (1993-2023)

Permanent grassland occupy some 12% of the area of the Masurian Landscape Park. The Cirsio-Polygonetum plant association was distinguished on the semi-natural meadows situated on the peat-marsh soil. Changes in botanical composition of the meadow sward and the productivity of DM, against a background of different mineral fertilization, were examined in a medium-scale plot experiment. It was concluded that both aspects ofutilization must be accorded high priority in the case of extensively managed meadows: medium level of forage production and the landscape conservation.


Reserving Pastures In Communal Grasslands By Agropastoralists Of Tanzania, M L. Kusekwa, A J. Mwilawa, J.K K. Msechu Jun 2024

Reserving Pastures In Communal Grasslands By Agropastoralists Of Tanzania, M L. Kusekwa, A J. Mwilawa, J.K K. Msechu

IGC Proceedings (1993-2023)

Studies were conducted in “Maasai” and “Gogo” tribal communities to gain understanding of traditional management of reserved pastures. Survey techniques were used and forage production and chemical composition were estimated. Household heads were invariably old men who had no formal education. Household size averaged 14 and 11, in Maasai and Gogo tribes respectively. Most reserved pastures were privately owned. Over 90% of pastoralists preferred individual ownership of reserved grazing. Herbage production was 2510 kg DM/ha in Maasai and 3680 kg DM/ha in Gogo locations. Pastures and low protein content (5.1-6.5% CP). Constraints to reserve grazing strategies were land and water …


Impact Of Extensive Management On Demography Of One Invasive Species Of Permanent Grasslands, D Magda Jun 2024

Impact Of Extensive Management On Demography Of One Invasive Species Of Permanent Grasslands, D Magda

IGC Proceedings (1993-2023)

The objective of this study is to show the effect of extensive practices on the population dynamics of a grassland species (Chaerophyllum aureum) in order to control invasion process. Fertilisation intensity (none or 45g/m2), number (none, one or two) and date of cutting (before or after seed maturity) have been experienced on permanent plots in fields to follow consequences on demography of adults and seedlings. Adult density is regulated through cutting effect and intraspecific competition process. Reduction of competition by cutting leads to a paradoxal highest adult survival rate in on cut treatment compared with abandoned invaded fields. …


Influence Of Drying Method And Temperature On Ruminal Degradable Protein Of Switchgrass, D E. Farnham, K J. Moore, J R. George Jun 2024

Influence Of Drying Method And Temperature On Ruminal Degradable Protein Of Switchgrass, D E. Farnham, K J. Moore, J R. George

IGC Proceedings (1993-2023)

The nutritional value of herbage protein fed to ruminant livestock can be influenced greatly by the extent to which it is degraded in the rumen. This study was conducted to determine if drying method and temperature alters measurements of in situ ruminal escape protein (EP) of switchgrass herbage. Switchgrass harvested at the pre-heading stage was either air dried, freeze dried, or oven dried at 38, 49, 60, or 710 C. Samples from each of the six drying treatments were digested in situ in Dacron bags for 4, 8, 12, or 16 h. Drying treatment had a significant impact on EP …


Development Of Natural Horse Pastures In Finland In The 1900s, H Jansson, K H. Jansson, A Olin, T Talikka, J Pykala Jun 2024

Development Of Natural Horse Pastures In Finland In The 1900s, H Jansson, K H. Jansson, A Olin, T Talikka, J Pykala

IGC Proceedings (1993-2023)

The purpose of the study was to assess the importance of natural pastures as a growing environment for horses and, at the same time, to evaluate the landscape value of such pastures. Another aim was to look at possible ways of conserving areas which have been in use as horse pastures for a long period of time as traditional biotopes belonging to the Finnish horse grazing culture, and to examine how their management and care could be improved.


Relationship Of Soil To Native Pasture In A Flooding Pampa Area (Argentine), S P. Debelis, A A. Bozzo, A Bujan, M B. Barrios Jun 2024

Relationship Of Soil To Native Pasture In A Flooding Pampa Area (Argentine), S P. Debelis, A A. Bozzo, A Bujan, M B. Barrios

IGC Proceedings (1993-2023)

The influence of the topography in soils found in the area surrounding the Chascomús lagoon is examined. The study of the profiles within the representative transect in each microenvironment reveals changes related to its traits. Its relationship with the vegetation present in each toposequence position was observed. The worsening of the natural drainage conditions, are related to reduction of organic matter, increase in the values of pH and PSI, greater intensity of hydromorphic traces and appearance of groups of characteristic species.


Extensification Of Sheep Grazing Systems: Effects On Soil Nutrients, Species Composition And Animal Production, C A. Marriott, I J. Gordon Jun 2024

Extensification Of Sheep Grazing Systems: Effects On Soil Nutrients, Species Composition And Animal Production, C A. Marriott, I J. Gordon

IGC Proceedings (1993-2023)

The effects of ceasing fertiliser inputs to perennial ryegrass/white clover swards, combined with patterns of seasonal grazing, on soil nutrient status, floristic composition and animal production (ewes and single lambs) were studied in a long-term experiment at three upland sites in Scotland. Four unfertilised treatments had a factorial combination of seasonal grazing in summer and autumn at two sward heights (4 and 8 cm). There was also an ungrazed, unfertilised control and a fertilised treatment (140 kg N/ha plus maintenance P and K), grazed at 4 cm sward height in both seasons. All treatments were imposed annually from 1990/91. By …


Grassland Management For Geese: Sustainable Use For Conservation And Agriculture, S M. Percival, R Lilley Jun 2024

Grassland Management For Geese: Sustainable Use For Conservation And Agriculture, S M. Percival, R Lilley

IGC Proceedings (1993-2023)

Increasing numbers of overwintering wild geese have caused considerable problems to agriculture but are often also of conservation concern as their populations are relatively small. Islay, Scotland, is one site where this problem is particularly acute. We studied the two goose species which use this site, the barnacle goose, Branta leucopsis, and the white-fronted goose, Anser albifrons flavirostris, and found that they preferred younger pastures located closer to their roost sites. These preferred areas could be important in developing a sustainable strategy for future goose management. Further non-sustainable population increases might be avoided by increasing disturbance in these areas.


Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso Apr 2024

Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso

IGC Proceedings (1993-2023)

Results from a series of six comparative lamb grazing trials with temperate forages are summarised, and compared with results from the literature. Condensed tannin (CT) concentrations in the diet ranged from 0.12% to 0.47% on a dry matter (DM) basis. Values were generally similar for Yorkshire fog (Holcus lanatus), perennial ryegrass (Lolium perenne) and annual ryegrass (L. multiflorum), each grown with white clover (Trifolium repens), in similar circumstances. Concentrations for tall fescue (Festuca arundinacea)/white clover pastures were relatively low, but may have been artefacts. Drenching with polyethylene glycol (PEG) to bind …


Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake Apr 2024

Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake

IGC Proceedings (1993-2023)

A study was carried out to evaluate the tannin content and crude protein degradation of leaves and twigs from indigenous browsable trees which provide feed for grazing livestock on natural rangelands of Botswana. These browses include the families Leguminosae (Acacias), Capparidaceae (Boscias), Combretaceae (Combretum) and Tiliaceae (Grewias). These were found to be of good nutritive value, with the leaves having a high content of crude protein (9 - 16%) and a wide range of dry matter digestibility (37 - 69.82%). The correlation between crude protein disappearance and tannin content was found to be negative (-0.582) and significant (P<0.05).


Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush Apr 2024

Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush

IGC Proceedings (1993-2023)

The rate of formation of nitrate and ammonium in the soil under dung patches was compared for dung from animals fed either ryegrass (Lolium perenne)/white clover (Trifolium repens) or ryegrass/Lotus pedunculatus forage. Tannin derived from the Lotus did not inhibit ammonification in the soil under dung but nitrate formation was strongly inhibited. The results support the theory that polyphenolics may bind to nitrite in acid soils and cause immobilisation of mineral nitrogen. Apart from their effect of reducing the proportion of dietary nitrogen excreted in urine, tannins in animal diets may make a further contribution to …


Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer Apr 2024

Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer

IGC Proceedings (1993-2023)

A feeding trial was carried out to determine the effect of extractable condensed tannins (ECT) concentration and tannin astringency in tropical legumes on nitrogen (N) digestion by sheep. Test legumes were Desmodium ovalifolium (Do) and Flemingia macrophylla (Fm) which had similar concentrations of Extractable CT (9% DM) but tannins with different degree of astringency (Do, 0.6 and Fm, 0.3 g protein bound/g of ECT). Chopped sun-dried forage of each legume was sprayed with either water (control) or polyethylene glycol (PEG, 3.5% DM) to reduce ECT and fed to 8 sheep with ruminal and duodenal canulas arranged in a replicated 4 …


Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. Mcnabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn Apr 2024

Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. Mcnabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn

IGC Proceedings (1993-2023)

The in vitro precipitation of ribulose-1,5-bisphosphate carboxylase (Rubisco) by condensed tannin (CT) extracted from Lotus corniculatus and Lotus pedunculatus and the effect of these CT on the in vitro rumen degradation of Rubisco was used to compare the reactivity of these CT. The chemical structure of CT from Lotus corniculatus was homogenous with epicatechin stereochemistry and mostly procyanidin units. The CT from Lotus pedunculatus was heterogenous with mostly prodelphinidin units. The amount of CT required to precipitate all the Rubisco when total soluble leaf protein was incubated with CT from Lotus corniculatus and Lotus pedunculatus was similar. Although CT from …


Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye Apr 2024

Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye

IGC Proceedings (1993-2023)

Field-drying reduces extractable condensed tannin (CT) of sericea lespedeza [Lespedeza cuneata (Dum-Cours) G. Don], but effects on specific bound and unbound forms of CT and the relationship to protein and fiber digestion in ruminants are unclear. Intake and digestibility of fresh-frozen and field-dried high- and low-tannin sericea were investigated in a feeding trial with sheep (Ovis spp.). Field-drying had no effect on crude protein (CP) and fiber content of sericea, but shifted CT from extractable to bound forms. Digestion coefficients for CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were lower for high-tannin sericea than the low-tannin …


Alteration Of Condensed Tannin Sythesis In Transgenic Forage Legumes, F Paolocci, G Tanner, S Arcioni, F Damiani Apr 2024

Alteration Of Condensed Tannin Sythesis In Transgenic Forage Legumes, F Paolocci, G Tanner, S Arcioni, F Damiani

IGC Proceedings (1993-2023)

The transformation of Lotus corniculatus plants with the maize gene Sn, reorganizes the tissue specificity of condensed tannins accumulation. In particular the transformed plants show an increase of tannin content in roots and a decrease in leaves. Molecular and enzymatic analyses suggest that the transgene can functionally substitute an endogenous unknown gene not expressed in roots and induces its silencing when it is expressed. These findings could have applications for reducing tannin content in unpalatable plants and for cloning genes involved in tannin synthesis.


Comparison Of The In Vitro Fermentation Characteristic Of Fractionated Alfalfa And Sainfoin, L R. Mcmahon, M Goto, T A. Mcallister, G A. Jones, K J. Cheng Apr 2024

Comparison Of The In Vitro Fermentation Characteristic Of Fractionated Alfalfa And Sainfoin, L R. Mcmahon, M Goto, T A. Mcallister, G A. Jones, K J. Cheng

IGC Proceedings (1993-2023)

Alfalfa and sainfoin leaves were lyophilized and ground (A, S, respectively) or were fractionated into soluble (ASOL, SSOL) and insoluble (AINS, SINS)components and lyophilized and incubated in vitro with diluted ruminal fluid for 24h. Whole leaf and soluble fractions were also incubated with polyethylene glycol 8000 (PEG). Gas production (GP), ammonia concentration [NH3] and volatile fatty acid (VFA) production were lower (P< 0.05) from S and SSOL than from A and ASOL Insoluble fractions differed only in [NH3] (SINS < AINS, P < 0.05). Inclusion of PEG increased (P < 0.05) GP, [NH3] and VFA production from whole leaf and soluble fractions of sainfoin, but not alfalfa. Inactivating the condensed tannins in sainfoin with PEG overcame differences in degradability between these two forages.


Differences In Chemical Composition Among Provenances Of Tree Fodder Species In A Subhumid Environment: Relation To Use As Supplements, B H. Dzowela, L Hove, P L. Mafongoya Apr 2024

Differences In Chemical Composition Among Provenances Of Tree Fodder Species In A Subhumid Environment: Relation To Use As Supplements, B H. Dzowela, L Hove, P L. Mafongoya

IGC Proceedings (1993-2023)

Studies were initiated in a subhumid Southern African environment to assess the chemical composition and nutritive value of Acacia angustissima (Mill.) Kuntze, Calliandra calothyrsus Meiss. and Leucaena species. The objective was to determine variability in crude protein (CP) concentration, acid detergent fibre (ADF), neutral detergent fibre (NDF), and soluble and insoluble proanthocyanidins from fodder samples of species, subspecies and provenances. A wide range was found in these parameters. The implications of these chemical composition factors, especially proanthocyanidins, on the use of these browse fodders in livestock feeding systems are discussed.


Nutritional Implications Of Bound Proanthocyanidins, H P.S Makkar, K Becker Apr 2024

Nutritional Implications Of Bound Proanthocyanidins, H P.S Makkar, K Becker

IGC Proceedings (1993-2023)

The correlation between protein binding capacity of proanthocyanidin-rich neutral detergent fiber (NDF) and their proanthocyanidin (PAs) content was very low (r = -0.21; n = 6). These PAs-rich NDF did not affect growth of a tannin-sensitive strain of Clostridium perfringens. A substantial amount of bound PAs (75 to 92 %) disappeared from the NDF in 24 h of fermentation in an in vitro incubation medium containing rumen microbes. Addition of a tannin-binding agent, polyethylene glycol to the incubation medium containing rumen microbes and browses made free of extractable tannins or NDF rich in bound PAs increased the gas production up …