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Full-Text Articles in Life Sciences

Characterising The Fermentation Capabilities Of Gut Microbial Populations From Different Breeds Of Cattle And Sheep Grazing Heathland, D. R. Davies, M. D. Fraser, V. J. Theobald, E. L. Bakewell Mar 2023

Characterising The Fermentation Capabilities Of Gut Microbial Populations From Different Breeds Of Cattle And Sheep Grazing Heathland, D. R. Davies, M. D. Fraser, V. J. Theobald, E. L. Bakewell

IGC Proceedings (1997-2023)

Previous studies have demonstrated differences in the diet composition of sheep and cattle when grazing heather moorland, and such differences may in turn lead to differences in rumen fermentation characteristics and associated adaptation to diet. To investigate this further an in vitro gas production experiment was conducted using inocula from different breeds of cattle and sheep grazing heathland.


The Performance Of Cattle On Lowland Species-Rich Neutral Grassland At Three Contrasting Grazing Pressures, B. A. Griffith, J. R.B. Tallowin Mar 2023

The Performance Of Cattle On Lowland Species-Rich Neutral Grassland At Three Contrasting Grazing Pressures, B. A. Griffith, J. R.B. Tallowin

IGC Proceedings (1997-2023)

Grazing is an essential management practice for maintaining the nature conservation value of lowland semi-natural neutral grassland to control succession and create different faunal habitats via structural heterogeneity within the pasture (Duffey et al., 1974). However, there is a paucity of information on what would constitute a sustainable grazing intensity that will deliver the wildlife objectives and what the consequences of this management would be on growth rate of livestock and overall pasture output. An experiment was designed to quantify the ecological and agronomic consequences of imposing different grazing intensities on species-rich neutral grassland. The results will provide sward-based …


In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan Feb 2023

In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan

IGC Proceedings (1997-2023)

Grazed grass is the predominant feed in Irish dairy and beef cattle production systems. Knowledge of the degradability characteristics of protein in Irish forages is necessary for the establishment of protein values (PDIE and PDIN values) for these. This knowledge would also facilitate more accurate formulation of supplements for grass diets with the potential to reduce nitrogen (N) excretion.


Pasture Land Management System Decision Support Software, G. E. Groover, S. R. Smith, N. D. Stone, J. J. Venuto, J. M. Galbraith Feb 2023

Pasture Land Management System Decision Support Software, G. E. Groover, S. R. Smith, N. D. Stone, J. J. Venuto, J. M. Galbraith

IGC Proceedings (1997-2023)

Controlled or rotational grazing provides benefits to producers and society through profitable and sound management of grazing land and livestock. Pasture land management system (PLMS) is a decision support system developed to help university, government, and professionals provide technical pasture management assistance to beef and dairy producers. The PLMS focuses on the balance between seasonal forage supply and nutrient demand in a dairy or beef cattle operation. It allows users to explore and compare alternatives (dividing fields into multiple paddocks, changing stocking rates, and forage species) through a visual display and embedded simulation. Users enter a description of the farm …


The Feeding Value Of Conserved Whole-Crop Wheat And Forage Maize Relative To Grass Silage And Ad-Libitum Concentrates For Beef Cattle, K. Walsh, P. O'Kiely, F. O'Mara Feb 2023

The Feeding Value Of Conserved Whole-Crop Wheat And Forage Maize Relative To Grass Silage And Ad-Libitum Concentrates For Beef Cattle, K. Walsh, P. O'Kiely, F. O'Mara

IGC Proceedings (1997-2023)

Grass is the predominant forage ensiled in Ireland. However, the relatively modest yields achieved in a single harvest allied to variability in digestibility and ensilability (and thus in intake and animal performance response) and the likelihood of effluent production create disadvantages for grass silage compared to the potential of some alternative forage crops. Thus, alternative forages are worthy of consideration on many farms. The objectives of this study were to quantify the relative intake, digestibility and performance of beef cattle offered grass silage, forage maize silage and whole-crop wheat (fermented or urea-treated), rank these relative to cattle offered an ad …


Nutritive Value For Finishing Beef Steers Of Wheat Grain Conserved By Different Techniques, P. Stacey, P. O'Kiely, A. P. Moloney, F. P. O'Mara Feb 2023

Nutritive Value For Finishing Beef Steers Of Wheat Grain Conserved By Different Techniques, P. Stacey, P. O'Kiely, A. P. Moloney, F. P. O'Mara

IGC Proceedings (1997-2023)

Wheat grain harvested at dry matter (DM) concentrations above 860 g/kg is slow to deteriorate during long-term storage. However, high moisture grain (HMG) ranging from below 600 to 750 g DM/kg is conserved on some farms in the form of anaerobic storage of acid-treated, rolled wheat (AR) and urea-treated whole-wheat (UN) (Stacey et al., 2003). This experiment quantified the nutritive value for beef cattle of standard wheat grain (propionic acid-treated and rolled:PR) compared to AR and UN at different levels of intake.


Intake Characteristics Of Diploid And Tetraploid Perennial Ryegrass Varieties When Grazed By Simmental X Holstein Yearling Heifers Under Rotational Stocking Management, R. J. Orr, J. E. Cook, K. L. Young, R. A. Champion, A. J. Rook Feb 2023

Intake Characteristics Of Diploid And Tetraploid Perennial Ryegrass Varieties When Grazed By Simmental X Holstein Yearling Heifers Under Rotational Stocking Management, R. J. Orr, J. E. Cook, K. L. Young, R. A. Champion, A. J. Rook

IGC Proceedings (1997-2023)

Orr et al. (2003) measured large differences in dry matter (DM) intake rate between 15 intermediate-heading perennial ryegrass varieties when they were continuously stocked with sheep and subsequently explored the extent to which, for 5 of these varieties, these differences could be explained by chemical and morphological traits (Orr et al., 2004a) which could be targeted in grass breeding programmes. Here, four of the 15 varieties, which within ploidy had low or high intake characteristics when grazed by sheep, were rotationally stocked with cattle and intake and sward factors were measured.


Genetic Characteristics Required In Dairy And Beef Cattle For Temperate Grazing Systems, F. Buckley, C. Holmes, M. G. Keane Feb 2023

Genetic Characteristics Required In Dairy And Beef Cattle For Temperate Grazing Systems, F. Buckley, C. Holmes, M. G. Keane

IGC Proceedings (1997-2023)

Key points

  1. Only about 10% of the world’s milk is produced from grazing systems. Consequently the majority of dairy cattle have not been selected under grazing, nor on seasonal systems. This is not true for beef cattle, for which the majority, especially the dams, are managed under seasonal grazing systems.

  2. In grazing systems daily feed intake is limited to lower levels than are achievable on concentrate plus conserved forage rations. Consequently, cows most suited to grazing environments are likely to have a lower genetic potential for milk production than cows selected in high concentrate systems, to minimise their relative energy …


Nitrogen Leaching From Cattle, Sheep And Deer Grazed Pastures In New Zealand, Keith Betteridge, Sterwart F. Ledgard, Coby J. Hoogendoorn, M. G. Lambert, Z. A. Park, Des A. Costall, P. W. Theobald Nov 2022

Nitrogen Leaching From Cattle, Sheep And Deer Grazed Pastures In New Zealand, Keith Betteridge, Sterwart F. Ledgard, Coby J. Hoogendoorn, M. G. Lambert, Z. A. Park, Des A. Costall, P. W. Theobald

IGC Proceedings (1997-2023)

The impacts of intensified grazing in New Zealand are being reflected in declining quality of groundwater, streams and lake water. Manipulation of ratios of grazing animal species may be one way farmers can reduce nitrogen (N) emissions to ground water. The present research quantifies nitrate and ammonium leaching losses from rotationally grazed sheep, cattle and deer pastures in a common environment.


Effect Of Winter Grazing Management Of Stockpiled Native Pastures Of Basaltic Soils Of Uruguay On Daily Gains Of Heifers, G. Pigurina, R. Castells, G. Reyes, E. J. Berretta Jan 2022

Effect Of Winter Grazing Management Of Stockpiled Native Pastures Of Basaltic Soils Of Uruguay On Daily Gains Of Heifers, G. Pigurina, R. Castells, G. Reyes, E. J. Berretta

IGC Proceedings (1997-2023)

The effect of three grazing systems of fall stockpiled native pastures on the winter gains of 66 Hereford heifers (135 kg) was studied. Treatments were: continuos grazing (CG); (C7) the plot was divided in 12 and each was grazed for 7 days and (C28), the plot was divided in 3 and each were grazed for 28 days. Heifers were weighed every 14 days and grazing behaviour was recorded. Stockpiled HM was greater (P< 0.05) in C7 and C28 than in CG (988, 912, and 604 kg DM/ha, respectively). Herbage allowance (HA) was greater (P< 0.01) in CG followed by C28 and C7 (11.7, 6.6 and 5.9 kg DM/100 kg LW, respectively). Post-grazing HM was greater (P0.05) in all pastures (CP 10.2%, NDF 71.2%, ADF 41.3% and ash 14.4%). Final LW of heifers were similar (P> 0.05) (167, 162 and 160 kg for CG, C7 and C28, respectively). A very mild winter favoured exceptional gains which tended to be higher in CG (0.353 …


Describing Cattle Grazing Distribution In Communal Rangelands Of The Eastern Cape South Africa: Towards Improving Livestock Rangeland Use, B. Gusha, A. R. Palmer Jan 2022

Describing Cattle Grazing Distribution In Communal Rangelands Of The Eastern Cape South Africa: Towards Improving Livestock Rangeland Use, B. Gusha, A. R. Palmer

IGC Proceedings (1997-2023)

This study used global positioning systems (GPS) to understand grazing distribution of three cattle in the communal rangeland of Eastern Cape, South Africa. Free ranging cattle were randomly selected from participating households and were fitted with neck GPS collars, which recorded geographic position every five-minute interval during wet and dry season. The study identified three production domains where cattle were reported to be spending most of their time grazing, separated by bound polygons on google earth Pro to further extract MODIS EVI???. The recorded GPS points were loaded into google earth Pro to analyse the distribution of cattle grazing in …


Agropastoral Systems An Alternative To Revert Pasture Degradation In The Cerrados Of Brazil: Preliminary Results, Manuel C. M. Macedo, J. A. M. Bono, A. H. Zimmer, F. P. Costa, Tsutomu Kanno, Cesar Heraclides Behling Miranda, A. N. Kichel Dec 2021

Agropastoral Systems An Alternative To Revert Pasture Degradation In The Cerrados Of Brazil: Preliminary Results, Manuel C. M. Macedo, J. A. M. Bono, A. H. Zimmer, F. P. Costa, Tsutomu Kanno, Cesar Heraclides Behling Miranda, A. N. Kichel

IGC Proceedings (1997-2023)

A long term experiment was set to test the hypothesis that agropastoral systems could improve crop and animal production, being more profitable and sustainable relative to economical, biological and environmental aspects, than continuous and traditional crop and grazing pasture systems. Five farming systems are being tested: two traditional (continuous soybean annual cropping and continuous pasture cropping) and three agropastoral systems (two combinations of four by four years of rotational crop-pasture systems and one by three years of crop-pasture rotation). Animal production in continuous pasture cropping measured as liveweight gain/ha (LWG) are declining along the years in the sub-treatment without fertilizer …


Goats To Control The Encroachment Of Undesirable Brush And Woody Species In Cattle Pastures, J-M. Luginbuhl, J. T. Green Jr., M. H. Poore, A. C. Conrad Dec 2021

Goats To Control The Encroachment Of Undesirable Brush And Woody Species In Cattle Pastures, J-M. Luginbuhl, J. T. Green Jr., M. H. Poore, A. C. Conrad

IGC Proceedings (1997-2023)

Field studies were initiated in an abandoned, overgrown 8.4 ha orchard left untouched for 15 years to evaluate the effectiveness of using goats (Capra hircus hircus) to manage undesirable vegetation. Goats alone (G: 30 does/ha) or cattle (Bos taurus) with goats (GC:17 does/ha and 3 steers/ha) were mob-grazed twice a year during four grazing seasons. Multiflora rose (Rosa multiflora Thunb.) canopy area decreased from 12 to 2.5 m2 in grazed pastures and multiflora rose live canes were 100% in the control, 0% in G, and only 8% in GC at the completion of the …


The Role Of Cattle Dung In Seed Dispersal Of Major Species In A Zoysia Japonica Pasture In Japan, K. Shimoda, S. Sakanoue Dec 2021

The Role Of Cattle Dung In Seed Dispersal Of Major Species In A Zoysia Japonica Pasture In Japan, K. Shimoda, S. Sakanoue

IGC Proceedings (1997-2023)

To evaluate the role of cattle dung in seed dispersal of major species in Zoysia japonica pasture in Japan, we investigated the species composition and density of seeds in cattle dung by means of a germination test. Of 20 major species which had a mean coverage of more than 0.1%, 90% were detected as seeds in cattle dung. In addition, the species composition and density of seeds in cattle dung differed among three sampling seasons. Seeds of the six most prevalent species in terms of coverage were detected from cattle dung during the growing season. Hence, we conclude that it …


Influence Of Grassland Management And Grazing By Different Farm Animals On Animal Performance And Flora Alterations, W. Jentsch, H.-D. Matthes, A. Admasu, H. Möhring Dec 2021

Influence Of Grassland Management And Grazing By Different Farm Animals On Animal Performance And Flora Alterations, W. Jentsch, H.-D. Matthes, A. Admasu, H. Möhring

IGC Proceedings (1997-2023)

The objectives of this study were to test the possibilities of using different farm animals for landscape care on extensive pasture, taking into account their particular performance, and to analyse alterations of the flora in consequence of grazing by different animals and various pasture management. Salers had the highest (836g/d) and Galloways (584g/d) the lowest live weight gain as compared with the other breeds (771g/d). Lambs had higher live weight when grazing together with cattle and horses (mixed grazing) than under one species grazing. The number of legume increased and that of grass decreased. Following 3 years the grazing animals …


Late Winter Dietary Overlap Among Greater Rheas And Domestic Herbivores On The Argentinean Flooding Pampa, G. Vacarezza, M. S. Cid, F. Milano Dec 2021

Late Winter Dietary Overlap Among Greater Rheas And Domestic Herbivores On The Argentinean Flooding Pampa, G. Vacarezza, M. S. Cid, F. Milano

IGC Proceedings (1997-2023)

This study evaluates the dietary overlap among greater rheas (Rhea americana L.) sheep and cattle in the Flooding Pampa, Buenos Aires, Argentina during late winter, when is observed the lowest forage availability. The work was carried out with the following forage classes (FC): warm and cool season grasses and forbs (legumes and no-legumes). Diet botanical composition was estimated by microanalysis of faeces. Principal Component Analysis and Kulcyznsky´s index of similarity were used for data analysis. Rhea populations selected diets with higher forb percentages. On the contrary, vegetation structure and their own morpho-physiology conditioned cattle to diets almost exclusively gramineous. …


Forage Management For Extending The Grazing Season, David W. Koch, C. M. Lux, J. W. Flake Dec 2021

Forage Management For Extending The Grazing Season, David W. Koch, C. M. Lux, J. W. Flake

IGC Proceedings (1997-2023)

Studies were conducted to determine ways to extend grazing season with forages adequate to meet the needs of grazing animals and to reduce the cost of livestock production. Perennial grasses were swathed, windrowed and left in the field until they were winter-grazed with bred heifers. Corn (Zea mays L.) was stockpiled for winter grazing with lambs and ewes. Windrowed grasses increased in acid detergent fiber (ADF) and neutral detergent fiber (NDF) compared with stored hay, but crude protein content, heifer weight gain and body condition change was similar for both forages. An economic value of $218 ha-1 from …


Intensive Grazing Systems For Beef Cattle Production, F. P. Fontenot, V. G. Allen, M. A. Cochran, N. B. Frank Dec 2021

Intensive Grazing Systems For Beef Cattle Production, F. P. Fontenot, V. G. Allen, M. A. Cochran, N. B. Frank

IGC Proceedings (1997-2023)

The objective of this study was to compare grazing systems that used rotational and continuous stocking for beef cows-calves and stocker cattle grazing fescue (Festuca arundinacea) and clover (Trifolium repens). For each system seven cows/calves and seven stocker steers were used within each of two replicates. The cows and stockers grazed stockpiled forage and were fed hay in winter, and grazed growing forage during spring and summer. Cows in the rotational system gained at a faster rate (P< . 05) from October to April than those in the continuous system. Daily gains of calves were higher (P< . 05) for the continuous system. Rate of gain during the last 28 days was higher (P< . 05) for the stockers in the rotational system. Average hay yields were not different for the two stocking systems, but more (P< . 05) hay was fed to the cattle in the continuous system. The system that used continuous stocking was more easily managed and required less labor and facilities.


Contract Grazing Of Young Beef Cattle On Ryegrass In The Southeastern Usa, David I. Bransby Dec 2021

Contract Grazing Of Young Beef Cattle On Ryegrass In The Southeastern Usa, David I. Bransby

IGC Proceedings (1997-2023)

The objective of this study was to evaluate contract grazing (in which the landowner grazes cattle owned by someone else for a specified fee) as an alternative to traditional ownership of the cattle, in order to improve profitability of grazing young beef cattle on annual ryegrass under limited availability of operating capital in the southeastern USA. Production data from a two-year grazing experiment were used as a basis for an economic analysis which assumed market prices for the beef industry in the region. Return/ha over animal and pasture costs was $312.20 for contract grazing, and $477.50 for purchased cattle. However, …


Integration Of Cattle And Improved Pastures Under Coconuts In Southern Luzon, Philippines, F. A. Moog, H. E. Diesta, A. G. Deocareza Dec 2021

Integration Of Cattle And Improved Pastures Under Coconuts In Southern Luzon, Philippines, F. A. Moog, H. E. Diesta, A. G. Deocareza

IGC Proceedings (1997-2023)

Results of two studies involving 1) grazing of Signalgrass (Brachiaria decumbens) pastures at different stocking and 2) cut-and-carry forages in smallholder farms for cattle under coconuts are presented. Grazing at 3 AU/ha and 2 AU/ha gave significantly higher LWG/ha (P 0.05) over 1 AU/ha but highest financial return was obtained from 2 AU/ha. Productivity of cattle on cut-and-carry forages in small farms varies among farmers with better animal performance directly related to quantity and quality of feeds offered and industriousness of individual farmers. Both studies showed the benefits derived from integration of cattle with improved pastures under coconuts.


Transgenic Maize Hybrid Crop Residues: Nutritive Value And Their Effects On Performance Of Grazing Beef Cows, S. K. Barnhart, J. R. Russell, M. J. Hersom, D. E. Farnham Nov 2021

Transgenic Maize Hybrid Crop Residues: Nutritive Value And Their Effects On Performance Of Grazing Beef Cows, S. K. Barnhart, J. R. Russell, M. J. Hersom, D. E. Farnham

IGC Proceedings (1997-2023)

Several maize (Zea mays) hybrids, including three transgenic hybrids containing Bacillus thuringiensis (Bt) enzymes (Bt-maize hybrids), were planted in a field study. Mature, midgestation, beef cows (Bos tarus) strip-grazed post-harvest residues as paddocks over 126 days. Body condition-scores and weights were monitored. Forage yield, weathering losses and forage composition were monitored on grazed and ungrazed areas. Forage selection and intake were estimated. Grain yields, dropped grain, initial crop residue concentrations of dry matter (DM), organic matter (OM) and in vitro digestible organic matter (IVDOM) yields were similar among hybrids. Hybrids varied in infestation of maize borers, …


Integrating Pastures Into The Traditional Slash-And-Burn Cycle In Northeastern Pará, Brazil, S. Hohnwald, B. Rischkowsky, R. Schultze-Kraft, J. M. King, A. P. Camarão Nov 2021

Integrating Pastures Into The Traditional Slash-And-Burn Cycle In Northeastern Pará, Brazil, S. Hohnwald, B. Rischkowsky, R. Schultze-Kraft, J. M. King, A. P. Camarão

IGC Proceedings (1997-2023)

A project to test possibilities to integrate pastures into the traditional slash-and-burn cycle of small farmers in the Bragantina region in northeastern Pará, Brazil, is presented. Whereas in practice the traditional grass-only pasture is managed separately from the crop/fallow cycle, two options for integration are tested: a Brachiaria humidicola pasture enriched with two bushy and one herbaceous legume, Cratylia argentea, Chamaecrista rotundifolia and Arachis pintoi, and a B. humidicola pasture allowing a controlled regrowth of secondary vegetation ("Capoeira"). The regeneration performance of these pastures for a subsequent cropping period is compared with plots of undisturbed regrowth of Capoeira …


Herbivore Preference For Afternoon- And Morning-Cut Forages And Adoption Of Cutting Management Strategies, H. F. Mayland, J. C. Burns, D. S. Fisher, Glenn E. Shewmaker, R. Carlstrom, D. S. Cash Nov 2021

Herbivore Preference For Afternoon- And Morning-Cut Forages And Adoption Of Cutting Management Strategies, H. F. Mayland, J. C. Burns, D. S. Fisher, Glenn E. Shewmaker, R. Carlstrom, D. S. Cash

IGC Proceedings (1997-2023)

Photosynthesizing forage plants accumulate total nonstructural carbohydrates (TNC) during daylight, but then TNC concentrations are reduced during the night. Afternoon-cut forage (PM) has greater TNC value and thus economic value, than morning-cut (AM). Livestock prefer PM-cut hay and this can be readily demonstrated by offering animals a choice of hays cut in PM and AM. Alfalfa growers in the western United States are readily adopting PM-cutting technology to increase profits.


Duration Of Regrowth Of Ryegrass (Lolium Perenne) Swards: Effects On Rumen Fermentation Of Lactating Dairy Cows, P. Chilibroste, S. Tamminga, H. Boer Nov 2021

Duration Of Regrowth Of Ryegrass (Lolium Perenne) Swards: Effects On Rumen Fermentation Of Lactating Dairy Cows, P. Chilibroste, S. Tamminga, H. Boer

IGC Proceedings (1997-2023)

The relative importance of duration of sward regrowth and rumen fill and fermentation on the control of grazing time and intake rate during the first grazing session of the day were studied. Four lactating dairy cows were allowed to graze ryegrass (Lolium perenne) swards, with five different regrowth periods after mowing (6, 9, 16, 22 and 30 d). The cows were allowed to graze until they stopped voluntarily. Samples of rumen liquid were taken at approximately 0, 30, 60, 120 and 240 min after the grazing session was finished. Concentration of volatile fatty acids (VFA) followed a significant …


Gastrointestinal Nematode Infections In Grazing Domestic Ruminants, M. Eysker Oct 2021

Gastrointestinal Nematode Infections In Grazing Domestic Ruminants, M. Eysker

IGC Proceedings (1997-2023)

World wide gastrointestinal nematode infections impair production of ruminants. Particularly in small ruminants control of these infections is seriously hampered by the development of resistance of the parasites against anthelmintic drugs. This implies that alternative control measures have to be implemented in order to maintain a sustainable ruminant industry. In this paper the various possibilities to achieve this are briefly discussed. The possibilities discussed include grazing management, vaccination, selective breeding, biological control, nutrition and the use of bioactive forages such as for instance plants containing condensed tannins. At the end it is concluded that combinations of these options should preferably …


Tree Competition Reduces Cattle Growth Rates In Eucalypt Woodlands Of Queensland, T. J. Hall, J. R. Douglas Oct 2021

Tree Competition Reduces Cattle Growth Rates In Eucalypt Woodlands Of Queensland, T. J. Hall, J. R. Douglas

IGC Proceedings (1997-2023)

The wiregrass/bluegrass (Aristida/Bothriochloa) native pasture community in Eucalypt woodlands is a major cattle producing resource in Queensland. The effects of poplar box tree (Eucalyptus populnea) competition (at 5 m2/ha tree basal area) and grazing pressure on pastures and on growth of Brahman-cross steers were measured in a grazing experiment. Treatments were 2 tree competition levels (live trees or clearing) by 3 grazing pressures (low - 25%, medium - 50% and high - 75% utilisation of annual pasture growth). Pasture yield and pasture foliage cover increased for 3 years from the reduction in tree competition …


Bloat In Ruminants: The Cell Rupture Hypothesis, B. P. Berg, T. A. Mcallister, K.-J. Cheng Oct 2021

Bloat In Ruminants: The Cell Rupture Hypothesis, B. P. Berg, T. A. Mcallister, K.-J. Cheng

IGC Proceedings (1997-2023)

An alfalfa (Medicago sativa L.) cultivar with a low initial rate of digestion (LIRD), AC Grazeland B, was developed to test the hypothesis that the rate of cell rupture was a cause of frothy bloat in cattle or sheep. The amount of cell wall increases and digestibility declines as plants mature. Thus the cell rupture theory also predicts that the bloat potential of alfalfa is related to maturity. This study compared the digestibility of cell walls (NDF) in LIRD cultivars with that of a standard, Beaver, in relation to maturity and bloat incidence. Fresh alfalfa was fed to wethers …


A Comparative Grazing Study Of Sheep And Cattle Diet Selection On Native Pastures In Uruguay, Fabio Montossi, G. Pigurina, E. J. Berretta, I. Santamarina Oct 2021

A Comparative Grazing Study Of Sheep And Cattle Diet Selection On Native Pastures In Uruguay, Fabio Montossi, G. Pigurina, E. J. Berretta, I. Santamarina

IGC Proceedings (1997-2023)

An experiment was carried out during winter, spring and summer 1997, on native pastures of the basaltic region of Uruguay to evaluate the effects of different herbage mass levels (high, medium and low) on sward characteristics and on sheep and cattle diet selection and grazing behaviour. Higher herbage masses resulted in increments in herbage accumulation and sheep bite weight: winter (1880, 1513 and 610 kg DM ha-1, P < 0.01; 199, 148 and 128 mg DM/bite, P < 0.01), and summer (3046, 2175 and 1172 kg DM ha-1, P < 0.01; 214, 175 and 143 mg DM/bite, P < 0.01) for high, medium and low herbage mass levels respectively. The nutritive value of diet selected by sheep and cattle was higher than that of the herbage on offer, and higher in sheep than in cattle: winter (10.2, 15.9 and 12.5% crude protein, CP, P < 0.05; 49.2, 32.4 and 38.1% acid detergent fiber, ADF, P < 0.01, and summer (7.4, 10 and 9.5% CP, P < 0.05; 51.1, 36.8 and 43% ADF, P < 0.01) for herbage on offer, sheep and cattle diets respectively. These contrasting results found in the nutritive value were closely associated with differences in the proportions of the botanical components recorded, particularly the differential contribution of dead material. This experiment quantified the importance of diet selection in determining the nutritive value of the forage eaten by sheep and cattle on the native pastures of the basaltic region of Uruguay and established some relationships between diet selection and grazing management, involving animal selectivity ability differences (sheep versus cattle) and seasonal effects.


A Sheep And Catlle Diet Selection Study On A Fertilized Native Sward In Uruguay, Fabio Montossi, E. J. Berretta, G. Pigurina, I. Santamarina Oct 2021

A Sheep And Catlle Diet Selection Study On A Fertilized Native Sward In Uruguay, Fabio Montossi, E. J. Berretta, G. Pigurina, I. Santamarina

IGC Proceedings (1997-2023)

This study was undertaken during winter, spring and summer 1997, located in the basaltic region of Uruguay to evaluate the effects of stocking rate (SR) and N and P fertilizer application on sward characteristics and on sheep and cattle diet selection and grazing behaviour. The treatments applied were: a) control (C; without fertilizer application using a SR of 0.9 stock units (SU)/ha), b) T1 (with N and P fertilizer application using a SR of 0.9 SU/ha), c) T2 (with N and P fertilizer application using a SR of 1.2 SU/ha) and d) T3 (with N and P fertilizer application using …


Influence Of Sward Height, Concentrate Supplementation And Season On Grazing Activity Of Beef Cows, O. J. Gekara, E. C. Prigge, W. B. Bryan, M. Schettini, E. L. Nestor Sep 2021

Influence Of Sward Height, Concentrate Supplementation And Season On Grazing Activity Of Beef Cows, O. J. Gekara, E. C. Prigge, W. B. Bryan, M. Schettini, E. L. Nestor

IGC Proceedings (1997-2023)

The influence of sward height, concentrate supplementation and season on daily pattern of forage consumption of lactating beef cows grazing cool season pastures was determined. Cows (n=24; BW=535±10.8 kg) were randomly assigned to eight plots maintained at sward heights (SH) of either 4-8 cm or 8-12 cm and fed three levels of concentrate supplement: none = 0 kg/day, low = 3.12 kg/day or high = 6.24 kg/day. Cows on lower SH had greater (P < .08) forage dry matter intake and spent an additional 1.2 hours/day (P < .01) grazing compared to the higher SH. Cows on lower SH consumed 7.7 kg/day of forage dry matter and grazed 9.4 hours/day whereas those on higher SH consumed 7.1 kg/day and grazed 8.2 hours/day. Cows on lower SH grazed 0.7 hours/day (P < .06) and 0.4 hours/day (P < .08) longer at 06:00-10:00 hour and 11:00-13:00 hour, respectively, compared to the higher SH. Grazing efficiency (kg of forage consumed/hour of grazing) decreased (P < .01) as season progressed. Season influenced duration of grazing activity (P < .01). Cows grazed 0.5 hours longer (P < .01) at 06:00-10:00 hour late in summer (August) compared to spring (May) and mid summer (June/July). Cows grazed 0.3 hours longer (P < .08) at 11:00-13:00 hour during spring compared to late summer.