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Positive Changes In Regional Vegetation Cover In Patagonia Shown By Maras Monitoring System, Gabriel E. Oliva, J. Gaitan Oct 2021

Positive Changes In Regional Vegetation Cover In Patagonia Shown By Maras Monitoring System, Gabriel E. Oliva, J. Gaitan

IGC Proceedings (1977-2023)

MARAS (Environmental monitoring of arid and semiarid lands) is a vegetation and soil monitoring system in Patagonia, a 700.000 km2 area in southern South America. Installed between 2008-2015 within INTA-Argentina and INIA-Chile national agricultural research institutes, it includes photographs, 500-point intercepts, 50-m canfield lines to detect patches, 10 land function observations and 0-10 cm soil samples in 458 ground sites. Data is centralized and freely accessible https://maras.inta.gob.ar. We analysed changes based in the first 255 reassessments made at 5-year intervals. At a regional scale significant changes (P < 0.05 paired T test) were detected for: perennial vegetation cover, that was originally 42% and increased +3.1%. Plant species richness of 13.7 species/monitor increased +0.7, bare soil of 35% decreased -7.9%. Length of bare soil interpatches was 157 cm and decreased -42 cm. Land function indexes of Stability 46.2%, Infiltration 45.1% and Recycling 31.0% showed small non-significant changes (-1.3, +0.7 and +1.42 respectively). Significant changes in soils under vegetated patches were: conductivity 0.59 dS/m increased +0.49, and pH 7.3 +0.33. Organic matter was 2.0% and increased 0.35%, and sand was 73% and increased 3%. Finer soil particles decreased non-significantly. Bare soil interpatches had 1.4% organic matter and also increased 0.33%, and clay, that initially was 9.3% reduced -2.3%. The long-term ground sites provide a means to monitor slow changes in these rangelands in relation to global climatic change and regional grazing patterns. Patagonia has currently the lowest domestic stocking rates of the last century and vegetation seems to be slowly growing in perennial cover, with significant reductions in exposed bare soil, increase in biodiversity and soil organic carbon.


Modelling Catchment-Scale Evapotranspiration And Net Primary Production In Sub-Humid African Grasslands: Towards Understanding Carbon And Water Trade-Offs In Communal Rangelands, A. R. Palmer, Z. Munch, L. Vermeulen Oct 2021

Modelling Catchment-Scale Evapotranspiration And Net Primary Production In Sub-Humid African Grasslands: Towards Understanding Carbon And Water Trade-Offs In Communal Rangelands, A. R. Palmer, Z. Munch, L. Vermeulen

IGC Proceedings (1977-2023)

Being able to confidently predict net primary production within intensively used rangeland systems has become the goal of many rangeland scientists. The communally-managed rangelands of Africa, with their very high livestock numbers, represent such a challenge, as above-ground biomass is most often depleted before it has had chance to accumulate. In order to provide more accurate estimates of NPP for these rangelands, we explored the use of direct measurements of canopy cover, standing biomass and leaf area index, against standard vegetation indices from the Sentinel 2 sensors. Following intensive field surveys, we developed regression models of the relationships between Sentinel …


Lowveld Savanna Bush Cutting Alters Tree-Grass Interactions, E. R. Wedel, J. B. Nippert, A. M. Swemmer Oct 2021

Lowveld Savanna Bush Cutting Alters Tree-Grass Interactions, E. R. Wedel, J. B. Nippert, A. M. Swemmer

IGC Proceedings (1977-2023)

Savannas are characterized by the coexistence of trees and grasses, and their interactions are modified by water availability and herbivore activity. Many savannas are experiencing bush encroachment, resulting in reduced herbaceous productivity and shifts in savanna structure. This study aims to understand the effects of tree density and tree cutting on herbaceous productivity, water use, and herbivore abundance in a mopane-dominated lowveld savanna. We present data from a 4-year mopane-cutting experiment in the Mthimkhulu Game Reserve bordering Kruger National Park (South Africa). We established three 60x60 m plots for experimental manipulation where mopane stems and re-sprouting shoots were cut 2-3 …


Status And Distribution Of Range Plants Genetic Resources In Al Sabaloga Biosphere Conservation Area, Sudan, Salma Abdelghaffar Hassan Alamin, Hala Ahamed Hassan Oct 2021

Status And Distribution Of Range Plants Genetic Resources In Al Sabaloga Biosphere Conservation Area, Sudan, Salma Abdelghaffar Hassan Alamin, Hala Ahamed Hassan

IGC Proceedings (1977-2023)

The study was conducted in the Al Sabaloga area in 2017. The objective of this study was to investigate the status and distribution of range plants genetic resources in the study area. Sample size of 131 was chosen randomly to collect primary data. The data were coded, summarized, tabulated and processed. Analysis was conducted using (SPSS) computer program. The results were presented in the form of a frequency distribution. The result of this study represented in an ecological zone in the study area about (67%) Nile bank and island, Goz (35%), Valley (22%), Plains (17%) and Mountains (17%). For example, …


Rejuvenation Of Rangelands – Role Of Diversity And Improvement Strategies Of Range Grasses, A. K. Roy, D. R. Malaviya, P. Kaushal Oct 2021

Rejuvenation Of Rangelands – Role Of Diversity And Improvement Strategies Of Range Grasses, A. K. Roy, D. R. Malaviya, P. Kaushal

IGC Proceedings (1977-2023)

In India, a major part of the rural economy is dependent on the grazing-based livestock husbandry which is unique integration of agriculture and livestock coupled with rich traditional knowledge. Ecosystems of common property resources had been a mainstay in rural economy and livelihood. The traditional grazing forage resources in arid and semi-arid regions have deteriorated a lot due to various factors including heavy grazing pressure, climate change and dominance of invasive species, thus, needs rejuvenation. Additionally, these are causing serious economic and ecological problems such as poor productivity, soil and water erosion and reduced carbon sequestration.

The genetic improvement of …


Soil Organic Carbon And Total Nitrogen Stock Response To Traditional Enclosure Management In Eastern Ethiopia, Mohammed Abdulahi, Abule Ebro, Lisanework Nigatu Oct 2021

Soil Organic Carbon And Total Nitrogen Stock Response To Traditional Enclosure Management In Eastern Ethiopia, Mohammed Abdulahi, Abule Ebro, Lisanework Nigatu

IGC Proceedings (1977-2023)

Traditional enclosures are widely used by pastoralists in East Africa. However, the response of basic soil properties to the establishment of traditional enclosure management remains poorly understood. The aim of this study was to investigate the impacts of traditional enclosure on soil organic carbon and total nitrogen stock in the Bordade rangelands, eastern Ethiopia. Soil samples were collected from twelve area enclosures and openly grazed areas at a depth of 0-30 cm. The samples were analyzed for soil organic carbon, total nitrogen and bulk density. There were significant differences between enclosure and openly grazed areas in soil organic carbon and …


Soil Carbon Stocks Are Stable Under New Zealand Hill Country Pastures With Contrasting Phosphorus And Sheep Stocking Regimes, Ronaldo Vibart, Alec D. Mackay, C. Mckenzie, Brian Devantier, Des A. Costall, E. Noakes, F. Bilotto Oct 2021

Soil Carbon Stocks Are Stable Under New Zealand Hill Country Pastures With Contrasting Phosphorus And Sheep Stocking Regimes, Ronaldo Vibart, Alec D. Mackay, C. Mckenzie, Brian Devantier, Des A. Costall, E. Noakes, F. Bilotto

IGC Proceedings (1977-2023)

A temporal and spatial assessment is required to quantify the effects of nutrient inputs and varying grazing management regimes on soil organic carbon (SOC) stocks under grazed pastures in complex landscapes. We examined SOC stocks under permanent pastures in three farmlets under a range of different annual phosphorus (P) fertiliser and associated sheep stocking regimes. The farmlets examined had either no annual P applied (NF), 125 kg single superphosphate (SSP) ha-1 (LF), or 375 kg SSP ha-1 (HF) on an annual basis since 1980. Soils were sampled to three depths (0-75, 75-150, 150-300 mm) in 2003 and 2020, …


Pre- And Post-Degradation Management Of Rangelands: Implications For Sustainable Management, S. K. Tuffa, A. C. Treydte Oct 2021

Pre- And Post-Degradation Management Of Rangelands: Implications For Sustainable Management, S. K. Tuffa, A. C. Treydte

IGC Proceedings (1977-2023)

Rangeland degradation directly affects livestock production, resulting in food insecurity and ecological instability. A shift in vegetation from grass to woody plants has severely affected cattle production in Ethiopian rangelands. Those grass species that are perceived by the pastoralists as highly palatable and desirable are currently decreasing in both quality and quantity. A reason for this decline has been claimed to be degradation owing to overgrazing and climate change. While appropriate management of livestock density in rangelands is essential for sustainable production and grassland ecosystem health, the management of dryland ecosystems is mired in controversy due to the complexity of …


Indian Forage Scenario – Region Wise Availability And Deficit, A. K. Roy, Rajiv K. Agrawal, N. R. Bhardwaj, Asim Kumar Misra, S. K. Mahanta Oct 2021

Indian Forage Scenario – Region Wise Availability And Deficit, A. K. Roy, Rajiv K. Agrawal, N. R. Bhardwaj, Asim Kumar Misra, S. K. Mahanta

IGC Proceedings (1977-2023)

In India, rapid urbanisation, changing food habit and higher purchasing power have increased the demand for animal based food products.Proper feeding strategies using green nutritious fodderis key to increase livestock production and productivity in economical and sustainable way.Three major sources of fodder are crop residues, cultivated fodder from arable land (irrigated and rainfed) and fodder from common property resources like forests, permanent pastures, grazing lands, cultivated wasteland, fallow lands etc.

Based on the livestock census, we estimated the green and dry fodder availability vis-a-vis demand and emerging deficit/surplus situation. The state wise livestock population for Cattle, Buffaloes, Goat, Sheep, Yak …


Grólind – Sustainable Land Use Based On Ecological Knowledge, B. Marteinsdóttir, E. F. Þórarinsdóttir, G. Halldórsson, J. H. Stefánsson, J. Þórsson, K. Svavarsdóttir, R. Finnsdóttir, S. Jónsdóttir Oct 2021

Grólind – Sustainable Land Use Based On Ecological Knowledge, B. Marteinsdóttir, E. F. Þórarinsdóttir, G. Halldórsson, J. H. Stefánsson, J. Þórsson, K. Svavarsdóttir, R. Finnsdóttir, S. Jónsdóttir

IGC Proceedings (1977-2023)

The highlands of Iceland play an important role as summer rangelands for sheep. Large areas are badly degraded and the sustainability of this practice has been questioned. To achieve sustainable land management it is necessary both to obtain data on ecosystem changes over time and to ensure that the results are used by land users and policy makers in their management plans.

Currently, the first long-term national vegetation and soil monitoring programme (GróLind) is being developed in Iceland. The programme is based on an agreement between the Icelandic National Associations of Sheep Farmers, the Farmers Association of Iceland, Ministry of …


Grasses And Ruminants That Will Help Save Space Ship Earth, A. M. Craig, L. L. Blythe Oct 2021

Grasses And Ruminants That Will Help Save Space Ship Earth, A. M. Craig, L. L. Blythe

IGC Proceedings (1977-2023)

For the last twenty years, it has been known that grasses are capable of extracting toxins from the soil. More recently, it has been shown that microorganisms from ruminants, especially sheep, can biodegrade certain toxins in plants and soil, including munition residues. The combination of these two processes act as an agricultural means to clear toxins and munitions from land has been termed Phyto-Ruminal-Bioremediation by the United States Department of Agriculture (USDA) as illustrated in the discussion below. As an example, plants containing toxins such as pyrrolizidine alkaloids can be cleared from pastures using sheep and their ruminant microorganisms. Use …


Mongolian Rangelands Have A Great Potential For Natural Recovery, Bulgamaa Densambuu, Sumjidmaa Sainnemekh, Brandon T. Bestelmeyer, Budbaatar Ulambayar, Burmaa Dashbal, Erdenetsetseg Baasandai Oct 2021

Mongolian Rangelands Have A Great Potential For Natural Recovery, Bulgamaa Densambuu, Sumjidmaa Sainnemekh, Brandon T. Bestelmeyer, Budbaatar Ulambayar, Burmaa Dashbal, Erdenetsetseg Baasandai

IGC Proceedings (1977-2023)

Mongolians are aware that rangeland degradation is accelerating due to the combination of unsustainable use and drought events, but the natural recovery of degraded rangeland and timelines for recovery are less well studied. In this paper, we describe the use of “recovery class” concepts in rangeland classification that are being used to evaluate rangeland condition and management impacts across Mongolia. Recovery classes are analogous to degradation classes already used in Mongolia, but are based on ecological site descriptions (ESDs) and provide information about expected recovery rates based on quantitative measurements. While the degradation levels communicate the severity of plant community …


Choosy Grazers And Plant Communities – Interactions Between Cattle Breeds And Vegetation In Semi-Natural Pastures, C. M. Pauler, Johannes Isselstein, J. Berard, T. Braunbeck, M. K. Schneider Oct 2021

Choosy Grazers And Plant Communities – Interactions Between Cattle Breeds And Vegetation In Semi-Natural Pastures, C. M. Pauler, Johannes Isselstein, J. Berard, T. Braunbeck, M. K. Schneider

IGC Proceedings (1977-2023)

It is well recognized that domesticated and wild ruminant grazers have an important impact on the composition of grassland vegetation, mainly by forage selection, trampling and defaecation. However, little is known on the effects of genetic diversity, for example differences among breeds of cattle. Cattle breeds differ in terms of robustness, growth rate, weight and probably also in movement and forage selection behaviour, which all could impact vegetation composition. Our study therefore aimed at identifying breed-specific differences in forage selection and behaviour and its consequences for vegetation. In a controlled experiment on semi-natural pastures in the Swiss Alps, suckler cows …


Germinable Soil Seed Bank Of Bothriochloa Macra Dominated Pasture In South-Eastern Australia, M. L. Mitchell, J. M. Virgona, A. Durling, F. W. Dempsey Oct 2021

Germinable Soil Seed Bank Of Bothriochloa Macra Dominated Pasture In South-Eastern Australia, M. L. Mitchell, J. M. Virgona, A. Durling, F. W. Dempsey

IGC Proceedings (1977-2023)

In native pastures, soil seed banks play an important role in conserving the genetic material in a plant population, influencing community structure and providing protection against adverse climatic conditions. One important native grass is Bothrichloa macra (Steud.) S.T.Blake (Red grass, Red-leg grass). This grass is a C4 indigenous perennial grass that is commonly found in native pastures in the high rainfall zone of south-eastern Australia.

At Tarrawingee, NE Victoria, (36°25´S, 146°31´E) and Wymah, southern NSW, (35°58´S, 147°11´E), Australia, two sites that had Bothriochloa macra as the dominant native grass were sampled. Three hundred cores (50 mm diameter and 50 …


Carbon And Nitrogen Pools In Soil Aggregates Were Affected By Grazing Component ---- Results From Dry And Wet Sieving Methods, N. Liu, Y. Q. Wei, Y. Pang, B. Wei, Y. J. Zhang Oct 2021

Carbon And Nitrogen Pools In Soil Aggregates Were Affected By Grazing Component ---- Results From Dry And Wet Sieving Methods, N. Liu, Y. Q. Wei, Y. Pang, B. Wei, Y. J. Zhang

IGC Proceedings (1977-2023)

Grazing intensity can affect soil carbon (C) sequestration in semiarid grassland, but less is known about the effects of grazing component (defoliation, trampling, excreta return and their combinations) on the C and Nitrogen (N) in soil aggregates. In this study, a simulated grazing experiment was established in a typical steppe of Inner Mongolia, and we investigated the impacts of different grazing component treatments on the different size of aggregates distribution and their C and N content from dry and wet physical separations. Different soil C fractions were showed in different sieving method. The C content of different aggregate size showed …


Enhanced Grazing Management Assessment Using Drone-Based Lidar Measurements, V. W. Temu, W. C. Hession, P. Sforza, H. Wang Oct 2021

Enhanced Grazing Management Assessment Using Drone-Based Lidar Measurements, V. W. Temu, W. C. Hession, P. Sforza, H. Wang

IGC Proceedings (1977-2023)

Globally, there is an urgent need of research-based technologies for small ruminant producers to benefit from rapidly growing market demands for ruminant meat and related food products from forage-based operations. However, effective forage-based animal production requires a rapid assessment, and monitoring of grazing management needs to adjust stocking rates and/or spatial animal distribution in a timely manner. Applicability of unmanned aerial vehicles (drones) for grazing management offers opportunities to rapidly estimate biomass build-ups, ground coverage, and monitor animal behaviour. The reliability of drone-based laser scanning (DLS) for monitoring warm-season grass responses to simulated grazing intensities was assessed at Virginia State …


Ecorestore: Decision Support System To Restore The Productivity Of Degraded Rangelands In Southern Africa, Klaus Kellner, Dirk Pretorius, C. Marais Oct 2021

Ecorestore: Decision Support System To Restore The Productivity Of Degraded Rangelands In Southern Africa, Klaus Kellner, Dirk Pretorius, C. Marais

IGC Proceedings (1977-2023)

Land degradation is a multifaceted problem that affects the agricultural productivity of land due to a loss of vegetation cover and can often be ascribed to bush encroachment in savanna and grassland rangelands. Bush encroachment entails the increase in abundance and density of indigenous and alien woody vegetation (i.e. shrub thickening), which has a negative impact on the tree-grass ratio, biodiversity, as well as on a range of ecosystem services that affect the well-being of land users, often causing an increase in poverty and the introduction of non-sustainable land management practices, especially in arid- and semi-arid regions mostly affected by …


Rangeland Management In A Changing World – Active And Passive Restoration Case Studies From Ethiopia, Tanzania, And South Africa, A. C. Treydte, S. A. Baumgartner, S. K. Tuffa, A. A. Abdeta Oct 2021

Rangeland Management In A Changing World – Active And Passive Restoration Case Studies From Ethiopia, Tanzania, And South Africa, A. C. Treydte, S. A. Baumgartner, S. K. Tuffa, A. A. Abdeta

IGC Proceedings (1977-2023)

Rangelands cover almost 50% of the earth’s land surface and are often found in marginal areas that often face climate extremes. The production of herbaceous biomass has strongly declined over the last decades due to overgrazing and adverse climatic conditions such as frequent droughts and flooding. While different rangeland restoration methods are being used, their effect on vegetation quality and quantity over time has rarely been experimentally tested and monitored. Our research comprises experiments of various rangeland restoration tools we have used across eastern and southern Africa. We conducted passive restoration through exclosure experiments and compared vegetation in and outside …


Counteracting Green Alder Shrub Expansion By Low-Input Grazing, M. K. Schneider, T. Zehnder, J. Berard, C. Pauler, M. Staudinger, Michael Kreuzer, A. Lüscher Oct 2021

Counteracting Green Alder Shrub Expansion By Low-Input Grazing, M. K. Schneider, T. Zehnder, J. Berard, C. Pauler, M. Staudinger, Michael Kreuzer, A. Lüscher

IGC Proceedings (1977-2023)

In the past decades, the decline of traditional agriculture has caused an abandonment of marginal pastures in many mountain areas of Europe. In the Swiss Alps, green alder (Alnus viridis) is the most abundant successional shrub. A survey of 24 pasture-shrub gradients showed that the encroachment by green alder, in contrast to other shrubs, is associated with a substantial decline in plant species richness. The understorey of alder is primarily populated by very few, broad-leaved herbaceous species benefitting from the atmospheric nitrogen fixed by actinomycetes in symbiosis with green alder. However, the understory vegetation also provides an underestimated …


Bee-Friendly Beef: Developing Biodiverse Pastures To Increase Ecosystem Services, J. Wagner, S. Ghajar, M. O’Rourke, B. Tracy Oct 2021

Bee-Friendly Beef: Developing Biodiverse Pastures To Increase Ecosystem Services, J. Wagner, S. Ghajar, M. O’Rourke, B. Tracy

IGC Proceedings (1977-2023)

The capacity of grasslands to provide ecosystem services, such as pollinator resources, is often limited by lack of plant biodiversity. This is true of grasslands in the eastern US that are dominated by tall fescue (Festuca arundinacea) a non-native, cool-season grass that is typically toxic to cattle. This paper summarizes a research project in Virginia, USA exploring the idea that ecosystem services provided by tall fescue-dominated grasslands can be improved by increasing the plant biodiversity available to beef cattle and bees. Within three 6.5 ha tall fescue grasslands, we established 0.8 ha plots with a 17 species mix …


Rangeland In Marajó Island, Brazilian Amazon, A Long History Of Commons For Small-Breeders, T. Barbosa, M. Opplert, R. Folhes, S. Carvalho, Jean François Tourrand Oct 2021

Rangeland In Marajó Island, Brazilian Amazon, A Long History Of Commons For Small-Breeders, T. Barbosa, M. Opplert, R. Folhes, S. Carvalho, Jean François Tourrand

IGC Proceedings (1977-2023)

Rangelands cover almost one third of the earth's surface and are characterized by a low productivity and high sociocultural value. But the lack of recognition of the environmental, social and economic values of rangelands, along with the expansion of agribusiness, tourism and urban sprawl give rise to a rangeland dilemma. This dilemma is found in various regions of the world, where this set of factors leads to the generally irreversible destruction of the rangeland. The process is recent in the Amazon rangeland, such as the eastern part of Marajó Island and the Low Amazon wetlands. A survey conducted on 90 …


Effects Of Herding On Rangeland Use Efficiency In Kenya, A. Seidel, F. Asch, B. Warth Oct 2021

Effects Of Herding On Rangeland Use Efficiency In Kenya, A. Seidel, F. Asch, B. Warth

IGC Proceedings (1977-2023)

Within each foraging itinerary, herders can intervene in the forage selection process, encouraging herds to use highly palatable and less palatable rangeland resources. Such a herding strategy could prevent rangeland degradation and increase livestock productivity. The objectives of this study were to examine forage availability and identify factors influencing stocking rates around night resting places on a ranch in Laikipia County, Kenya.

Forage availability was measured along six regularly spaced transects around night resting places corralling one herd of camels, one mixed herd of goats and sheep, and two herds of cattle, with biomass sampling points at 50-, 150-, 250-, …


Livestock Policy In Special Areas, Alberta, Canada, P. L. Strankman Oct 2021

Livestock Policy In Special Areas, Alberta, Canada, P. L. Strankman

IGC Proceedings (1977-2023)

Special Areas, Alberta, Canada, is a rural municipality of 2.1 million hectares (about 5 million acres) in south-eastern Alberta. It is home to almost 5000 residents, with a unique governance arrangement in Alberta. Most of the farms and ranches utilize a mix of crop and livestock primarily annual cereal and oil seed cultivation and beef cattle. These production units are usually a mosaic of privately-owned land and Crown land leased from the government.

It provides an interesting case study for the local, and national challenges facing western Canadian agriculture. It also provides an opportunity to contrast with different bioclimatic and …


Collaborative Construction Of A Method That Contributes To Improve The Decision Making In Associative Ranches By Controlling The Grass Allowance In A Context Of Climate Variability, Emilio Duarte Esteves, Rómulo Cesar, Javier Fernández, Marcelo Ghelfi, Valentina Herrera, Virginia Caravia, Rodrigo Iribarne, Federico De Brum, Héctor Rodríguez, Marcelo Pereira Machín Oct 2021

Collaborative Construction Of A Method That Contributes To Improve The Decision Making In Associative Ranches By Controlling The Grass Allowance In A Context Of Climate Variability, Emilio Duarte Esteves, Rómulo Cesar, Javier Fernández, Marcelo Ghelfi, Valentina Herrera, Virginia Caravia, Rodrigo Iribarne, Federico De Brum, Héctor Rodríguez, Marcelo Pereira Machín

IGC Proceedings (1977-2023)

Pasture management and the particular conditions of each year are responsible for productive results, farm income, and condition of the pasture. A simple and robust method that relates the available grass and the required grass was built in a participatory manner, and contributes to a critical reflection process among the group of decision-making, adapting to their context. In 17 farms from the Basalt region in Uruguay, grass and animals were monitored seasonally. A simple method was developed with farmers, and from de offer needed to meet production targets (KgMS/KgPV) the amount of grass requires was calculated. The grass height was …


Searching For Molecular Markers For Salt Tolerance In Rhodes Grass (Chloris Gayana Kunth), E. Taleisnik, M. Salgado, M. D. Bonafede, L. E. Manghers, H. Pérez, L. García Seffino, A. Castagnaro, D. G. Díaz Oct 2021

Searching For Molecular Markers For Salt Tolerance In Rhodes Grass (Chloris Gayana Kunth), E. Taleisnik, M. Salgado, M. D. Bonafede, L. E. Manghers, H. Pérez, L. García Seffino, A. Castagnaro, D. G. Díaz

IGC Proceedings (1977-2023)

Rhodes grass (Chloris gayana Kunth), a C4 forage grass, is regarded as salttolerant and exhibits intra- and inter-cultivar variability for this trait. Plants of cv Boma were selected for salt tolerance at the seedling and adult stages, cloned and characterized by RAPD and AFLP amplification patterns. Both techniques were equally efficient for fingerprinting these clones. More bands were obtained by AFLP but the ratio of polymorphic bands and the proportion present only in tolerant clones were the same by both methods. These bands, along with those exclusive for sensitive clones could be useful as markers for assisted selection.


Genetic Variability Within Two Adapted Populations Of Tall Wheatgrass (Thynopyrum Ponticum) In Argentina, A. Andrés, R. Guillen Oct 2021

Genetic Variability Within Two Adapted Populations Of Tall Wheatgrass (Thynopyrum Ponticum) In Argentina, A. Andrés, R. Guillen

IGC Proceedings (1977-2023)

The genetic variability within two adapted populations of tall wheatgrass (Thinopyrum ponticum) was evaluated in Argentina, as an introductory part of a breeding programme in progress at our Institute. The final aim of this programme is to provide new cultivars of tall wheatgrass, adapted to different management systems. Two hundred fifty plants per population were grown from seeds, clonally propagated and transplanted as a spaced-plant trial in a randomized design with three replicates. The results indicated large differences between genotypes within the two populations for most attributes measured, though there were no significant differences between populations. Attributes related …


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

Gastrointestinal Nematode Infections In Grazing Domestic Ruminants, M. Eysker

IGC Proceedings (1977-2023)

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 …


Plant Secondary Compounds; Their Impact On Forage Nutritive Value And Upon Animal Production, T. N. Barry, D. M. Mcneill, W. C. Mcnabb Oct 2021

Plant Secondary Compounds; Their Impact On Forage Nutritive Value And Upon Animal Production, T. N. Barry, D. M. Mcneill, W. C. Mcnabb

IGC Proceedings (1977-2023)

Both the anti-nutritional and beneficial effects of secondary compounds in a range of temperate and tropical forages have been reviewed. Major secondary compounds in temperate and tropical forage plants occur in the phenolic fraction and include condensed and hydrolysable tannins, phenolic monomers and lignin. Condensed tannins (CT) bind to plant protein by pH-reversible hydrogen bonding. In temperate legume forages this reduces rumen protein degradation and can increase the absorption of essential amino acids (EAA) from the small intestine, with reactivity depending on CT concentration, molecular weight and chemical structure. Low concentrations of CT in Lotus corniculatus (20-40g/kg DM) increased EAA …


A Strategy For Detecting Natural Anthelmintic Constituents Of The Grassland Species Plantago Lanceolata, D. L. Gustine, M. A. Sanderson, J. Getzie, S. Donner, R. Gueldner, N. Jennings Oct 2021

A Strategy For Detecting Natural Anthelmintic Constituents Of The Grassland Species Plantago Lanceolata, D. L. Gustine, M. A. Sanderson, J. Getzie, S. Donner, R. Gueldner, N. Jennings

IGC Proceedings (1977-2023)

A strategy to detect anthelmintic constituents in plantain (Plantago lanceolata) using a bioassay-driven purification approach was tested. Plantain consumed by cattle may control or reduce internal parasite titers, possibly due to the iridoid glucoside aucubin. Lyophilized, ground leaves of wild P. lanceolata were extracted with 95 % ethanol or boiling water containing calcium carbonate. Partially purified extracts (0 to 250 mg ml-1), 5 μg ml-1 of the anthelmintic levamisole, or 5 mg ml-1 of aucubin were tested with sheathed bovine parasites (Ostertagia ostertagi). The percent moving worms was unchanged for water controls …


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 (1977-2023)

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 …