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Prescribed Fire Plus Grazing Horses: A Sustainable Model To Decrease Fire Hazard In A Mountain Landscape, F. Torres-Manso, R. Pinto, A. Marta-Costa, P. Fernandes, M. Fernandes Oct 2021

Prescribed Fire Plus Grazing Horses: A Sustainable Model To Decrease Fire Hazard In A Mountain Landscape, F. Torres-Manso, R. Pinto, A. Marta-Costa, P. Fernandes, M. Fernandes

IGC Proceedings (1977-2023)

The mountain landscapes of northern Portugal have been modified through rural depopulation and the absence of rangeland management. As such, increased above-ground biomass and higher fire hazard resulted, as well as decreased ecosystem biodiversity. The objectives of the OpentoPreserve Interreg SUDOE project are to evaluate the effects of the combined use of prescribed fire with grazing horses, and also to develop strategies of socio-economic valorization of this model. Concerning the evaluation of prescribed fire and grazing effects, the experimental design consisted of three plots in the Natura 2000 Alvão/Marão Site, respectively Control, Fire x Grazing, and Fire. The Fire plots …


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 …


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 …


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 …


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 …


Exploring Drivers Of Invasiveness Of The Plant Species Senna Obtusifolia In Rangelands To Secure Forage Production In West Africa, O. Ouédraogo, A. Zaré, C. Bougma, S. Kambou, A. Linstädter Oct 2021

Exploring Drivers Of Invasiveness Of The Plant Species Senna Obtusifolia In Rangelands To Secure Forage Production In West Africa, O. Ouédraogo, A. Zaré, C. Bougma, S. Kambou, A. Linstädter

IGC Proceedings (1977-2023)

Rangelands in Sahelian countries are continuously over-grazed decreasing forage resources and causing rapid environmental changes. Senna obtusifolia is a less palatable plant species that becomes increasingly invasive. This research explored drivers of its invasiveness in the perspective to propose solutions to secure forage production in the pastoral reserves. Species composition and herbaceous aboveground biomass were assessed in rangelands with different levels of invasion of Senna obtusifolia along a climatic and land-use pressure gradient. A greenhouse experiment was conducted to test the competitiveness of this species. The development of Senna obtusifolia in rangelands affected significantly forage quantity. Indeed the biomass of …


Effects Of Parthenium Hysterophorus On Grassland Community In Nyando Sub-County, Kisumu County, Kenya, B. M. Mutua, W. Chiuri Oct 2021

Effects Of Parthenium Hysterophorus On Grassland Community In Nyando Sub-County, Kisumu County, Kenya, B. M. Mutua, W. Chiuri

IGC Proceedings (1977-2023)

Parthenium hysterophorus is an invasive alien species native to South and Central America. The plant is ranked as one of the most dreaded weeds of the world. Parthenium hysterophorus affects grassland community through the release of allelochemicals that inhibit the germination and growth of grass species. However, little is known about its effects on native grassland community in Nyando sub-county of Kenya. Therefore, this study sought to investigate the effects of P. hysterophorus on grass species, livestock production and its control. A total of 121 farm household heads were interviewed using semi-structured interview schedules. Descriptive analysis and the T-test at …


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 …


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 …


C3 Perennial Grass Dominates Mixed C3/C4 Grasslands After Invasion By A C3 Woody Sprouter, C. E. Cooper, R. J. Ansley, T. J. Steffens, D. B. Murray, T. Zhang Oct 2021

C3 Perennial Grass Dominates Mixed C3/C4 Grasslands After Invasion By A C3 Woody Sprouter, C. E. Cooper, R. J. Ansley, T. J. Steffens, D. B. Murray, T. Zhang

IGC Proceedings (1977-2023)

Honey mesquite (Prosopis glandulosa) encroachment has resulted in decreased C4 mid-grass production and increased C3 mid-grass in the Southern Great Plains of the US. Woody legumes have had similar effects in Africa, Australia, and South America. Prosopis initially facilitates Texas wintergrass (Nassella leucotricha) growth under canopies, in part because N-fixation by this woody legume enriches subcanopy soils, favoring C3 species. As stand density increases, Nassella extends into interspaces between trees as well. Here we report Nassella responses in several studies that either reduced Prosopis to indirectly impact Nassella or treated Nassella directly. In …


Chlorophyll Concentration (Spad Values) As An Indicator Of Crude Protein Content And As A Selection Criterion In Grass Breeding, N. Gáborèík Oct 2021

Chlorophyll Concentration (Spad Values) As An Indicator Of Crude Protein Content And As A Selection Criterion In Grass Breeding, N. Gáborèík

IGC Proceedings (1977-2023)

The main aim of the study was to analyse chlorophyll a + b content (SPAD values) determined by portable chlorophyllmeter (SPAD- 502, Minolta, Japan) and crude protein content in leaves of timothy, coocksfoot, perennial ryegrass and meadow fescue (total 24 cultivars). Differences between both parameters were confirmed and a close relationship between chlorophyll content (SPAD values) and crude protein concentration was found. Correlation coefficient between SPAD and crude protein varied from 0.541++ for ryegrass to 0.906++ for timothy. This fact should be used for selection of grasses with higher crude protein content and/or better use of mineral soil …


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 …


Effect Of Storage Time And Temperature On Recovery Of Synergistes Jonesii From Rumen Fluid And Feces, W. M. Andrew, M. J. Williams, M. J. Allison, C. C. Chase Jr., C. G. Chambliss, R. S. Kalmbacher, W. E. Kunkle Oct 2021

Effect Of Storage Time And Temperature On Recovery Of Synergistes Jonesii From Rumen Fluid And Feces, W. M. Andrew, M. J. Williams, M. J. Allison, C. C. Chase Jr., C. G. Chambliss, R. S. Kalmbacher, W. E. Kunkle

IGC Proceedings (1977-2023)

Synergistes jonesii is a rumen bacterium that degrades 3,4-dihydroxypyridine (3,4 DHP), the toxic breakdown product of mimosine in leucaena (Leucaena leucocephala). Fecal culture is the most practical way to determine S. jonesii presence in zoological ruminants, particularly if feces can be collected from night penning facilities. Fresh rumen fluid and fecal or fecal slurry (sheep [Ovis spp.] only, 1:4 wt to vol. feces and culture media) from cattle (Bos spp.) and sheep, known to be colonized by S. jonesii, were subjected various storage times (0, 6, 12, and 24 h) and temperatures (5, 23, and …


The Importance Of Animal Comfort For Animal Production In Intensive Grassland Systems, P. H. Hemsworth, J. L. Barnett Oct 2021

The Importance Of Animal Comfort For Animal Production In Intensive Grassland Systems, P. H. Hemsworth, J. L. Barnett

IGC Proceedings (1977-2023)

Animals utilise a wide range of regulatory systems to control the conditions within their bodies or homeostasis. These regulatory systems control for example, body temperature, nutritional state, water balance, social interactions and fear and these systems react to environmental and endogenous stimuli so as to correct or prevent displacements from the optimal range. The behavioural and physiological responses utilised by the animal are usually proportional to the challenge to homeostasis. The stress response commences with the central nervous system perceiving a potential challenge to homeostasis. Once the central nervous system perceives a threat, it develops a biological response or defence …


Nitrogen Fertiliser Effects On Perennial Ryegrass Nutritive And Nitrate Content During The Cool Season, Joseph L. Jacobs, Frank R. Mckenzie Oct 2021

Nitrogen Fertiliser Effects On Perennial Ryegrass Nutritive And Nitrate Content During The Cool Season, Joseph L. Jacobs, Frank R. Mckenzie

IGC Proceedings (1977-2023)

A study was undertaken to determine the effects of differing levels of nitrogen (N) application (0 (N1), 25 (N2), 50 (N3) and 75 kgN/ha (N4)) during late autumn (T1), early (T2) and late winter (T3) on the nutritive characteristics and nitrate content of perennial ryegrass. Changes in crude protein (CP) for all treatments at each application time were similar irrespective of level of N application. At the commencement of all treatments, the existing CP content was highest in N3, followed by N2, N1 and N0. Nitrate content decreased throughout T1 primarily due to dry conditions, whilst during T2, levels for …


Nitrogen Concentration In Cell Wall Of Warm-Season Perennial Grasses, G. F. C. Lima, Lynn E. Sollenberger, J. E. Moore Oct 2021

Nitrogen Concentration In Cell Wall Of Warm-Season Perennial Grasses, G. F. C. Lima, Lynn E. Sollenberger, J. E. Moore

IGC Proceedings (1977-2023)

The objectives of this experiment were to evaluate the influence of N fertilizer, age of regrowth, and season on concentration of N in cell-wall fractions of three warm-season perennial grasses (limpograss, [Hemarthria altissima (Poir.) Stapf et C.E. Hubb.], bermudagrass [Cynodon spp.], and bahiagrass [Paspalum notatum Flügge]. The herbage neutral detergent insoluble nitrogen (NDIN) fraction composed almost half of total N in these grasses. Though acid detergent insoluble nitrogen (ADIN) concentrations generally were 80 g kg-1 of total N or less, this fraction is indigestible and unavailable and composes a significant portion of a nutrient that may …


Studies On Feeding Value For Five Psammophyte Shrubs In Ningxia Region, Dongmei X., Weixian C., Sijia G., Xiangyun X. Oct 2021

Studies On Feeding Value For Five Psammophyte Shrubs In Ningxia Region, Dongmei X., Weixian C., Sijia G., Xiangyun X.

IGC Proceedings (1977-2023)

A trial was conducted on five psammophyte shrubs -Caragana intermedia, C. korshinskii, Hedysarum scoparium, H. laeve, Salix psammophylla in the post-fruit period in Ningxia, China. Chemical composition, palatability and in vitro digestibility were studied systematically. The feeding value was evaluated through Fuzzy multifactorial model. According to chemical composition, palatability and in vitro digestibility, C. intermedia, had the highest feeding value and C .korshinskii the lowest.


In Situ Dry Matter Ruminal Degradation Kinetics Of Prairie Grass And Annual Ryegrass Forage, J. R. Carrete, I. Ceconi Oct 2021

In Situ Dry Matter Ruminal Degradation Kinetics Of Prairie Grass And Annual Ryegrass Forage, J. R. Carrete, I. Ceconi

IGC Proceedings (1977-2023)

The objective of this study was to evaluate dry matter ruminal degradation kinetics, of prairie grass (Bromus catharticus Vahl.) and annual ryegrass (Lolium multiflorum), by using in sacco technique, on seven different harvesting dates. The forage was incubated in nylon bags, suspended in the rumen of four Hereford steers with a rumen fistula. The dry matter ruminal degradation was calculated through the exponential model P=a+b(1-exp(-ct)). Potential degradabilities (PD) were high and reduced across a temporal trend, ranging between 92,31 and 81,79g 100g -1 of dry matter (DM) for prairie grass (PG) and 95,06 and 77,44g 100g -1 …


Application Of Near Infrared Reflectance Spectroscopy (Nirs) To Forage Evaluation In Uruguay, D. Cozzolino, Y. Acosta, J. Garcia Oct 2021

Application Of Near Infrared Reflectance Spectroscopy (Nirs) To Forage Evaluation In Uruguay, D. Cozzolino, Y. Acosta, J. Garcia

IGC Proceedings (1977-2023)

Near infrared reflectance spectroscopy (NIRS) were used to assess the chemical composition of a wide range of forages. Nearly five hundred herbage samples covering a wide range of temperate pastures species and mixtures, previously analysed by conventional wet chemistry were scanned in reflectance with a NIRS 6500 (NIRSystems, Silver Spring, USA). The coefficients of determination in calibration (R2 ) and the errors in cross validation (SECV) were 0.98 (5.8), 0.94 (22.2), 0.97 (5.6), 0.94 (6.9) and 0.89 (19.7) for crude protein, in vitro organic matter digestibility, dry matter, ash and acid detergent fiber, in g kg –1 on a …


Seasonal Variation Of Brachiaria Spp. Quality In The Pantanal Of Mato Grosso Do Sul, Brazil, S. M. A. Crispim, E. L. Cardoso, F. Fernandes Oct 2021

Seasonal Variation Of Brachiaria Spp. Quality In The Pantanal Of Mato Grosso Do Sul, Brazil, S. M. A. Crispim, E. L. Cardoso, F. Fernandes

IGC Proceedings (1977-2023)

This study aims to evaluate the dry matter yield and the crude protein (CP) of Brachiaria decumbens and Brachiaria humidicola and soil covering by these species, considering stand lasting age and hydrologic cycle periods in the Pantanal, from November 1996 to November 1997. Dry matter yield presented differences between hydrologic cycle periods and age, and their interactions. B. decumbens and B. humidicola over 10 years comparison yielded the largest amount of dry matter yield, observed in February. B. humidicola growth rate was slower than B. decumbens. Pastures stand ages did not cause differences in crude protein, but differences have …


Continuous Digestibility Assessment Of Tropical Grasses, A. Chudy, T. Schmidt, A. Glatzle Oct 2021

Continuous Digestibility Assessment Of Tropical Grasses, A. Chudy, T. Schmidt, A. Glatzle

IGC Proceedings (1977-2023)

The feed value for cattle of three tropical grasses, Gatton (Panicum maximum cv. Gatton), Estrella (Cynodon plectostachyus) and Tifton-85 (Cynodon sp. cv. Tifton-85) was investigated during the growing period, using the method of “continuous digestibility estimation”. Results indicate that feed value is hardly influenced by the growth stage from the 90th day on. Common European in-vitro feed evaluation procedures are not to be recommended for tropical grasses as they presented consistently lower values than did in-vivo measurements.


Prediction Of Intake Of Hay Differing In Species And Maturity By Goats, S. W. Coleman, S. P. Hart, T. Sahlu Oct 2021

Prediction Of Intake Of Hay Differing In Species And Maturity By Goats, S. W. Coleman, S. P. Hart, T. Sahlu

IGC Proceedings (1977-2023)

Eight species of forage, a cool-season perennial (Festuca arundinacea) and annual grass (Triticum aestivum), four warm-season perennial grasses (Bothriochloa caucasica, B. ischaemum, Cynodon dactylon, and Tripsacum dactyloides), a warm season annual (Digitaria sanguinalis) and a perennial legume (Medicago sativa), were cut at two or three maturities to provide a wide array of quality difference (n=20). Twenty wether goats (Capra hicus) were fed the hays in four different trials using an incomplete block so that each hay was fed to four different goats. Alfalfa produced the highest DM, …


Effect Of Level Of Surface Spoilage On The Nutritive Value Of Maize Silage Diets, K. K. Bolsen, L. A. Whitlock, G. L. Huck, M. K. Siefers, T. E. Schmidt, R. V. Pope, M. E. Uriarte Oct 2021

Effect Of Level Of Surface Spoilage On The Nutritive Value Of Maize Silage Diets, K. K. Bolsen, L. A. Whitlock, G. L. Huck, M. K. Siefers, T. E. Schmidt, R. V. Pope, M. E. Uriarte

IGC Proceedings (1977-2023)

This study determined the effect of surface spoilage in the diet on feed intake and nutrient digestibilities using growing steers fed whole-plant maize silage-based diets. A bunker silo, 0.9 m in depth, and a 2.7 m diameter AgBag were filled with alternating loads of chopped forage. After 90 days, the bunker was sealed with a sheet of polyethylene, and this silage was designated “spoiled”. The silage in the AgBag was designated “normal”. The four diets contained 90% silage and 10% supplement (dry matter basis), and the proportions of silage in the diets were A) 100% normal, B) 75% normal: 25% …


Selenium And Sulphur Concentrations In Primary Growths Of Different Plant Communities, W. Opitz Von Boberfeld Oct 2021

Selenium And Sulphur Concentrations In Primary Growths Of Different Plant Communities, W. Opitz Von Boberfeld

IGC Proceedings (1977-2023)

The factorised evaluated data of seven different grassland swards and two harvest dates of primary growths led to following results: Regarding the concentrations of selenium and sulphur, a selenium antagonist, and the N/S ratio, there were no significant plant community x harvest date, plant community x year, and harvest date x year interactions. The selenium concentrations, which never met the requirements of ruminants, were the highest in young herbage of a Bromion racemosi community reaching 49 µg kg-1 DM. The average of all swards and treatments was 33 µg kg-1 DM of selenium. Apparently, repeated application of selenate-bearing …


Canopy Characteristics, Ingestive Behaviour And Herbage Intake In Cultivated Tropical Grasslands, Lynn E. Sollenberger, J. C. Burns Oct 2021

Canopy Characteristics, Ingestive Behaviour And Herbage Intake In Cultivated Tropical Grasslands, Lynn E. Sollenberger, J. C. Burns

IGC Proceedings (1977-2023)

Compared to temperate systems, there have been few detailed assessments of canopy characteristics and associated grazing behavior in planted tropical grasslands. Reasons include the large number of forage species used in warm climates, the diversity of their morphology, research priorities emphasizing germplasm evaluation and management, and limited resources. This review describes canopy attributes of C4 grass pastures, highlights the most important relationships between grazing behavior and these canopy characteristics, and discusses the implications of canopy characteristics and grazing behavior for long-term intake and animal performance. It is suggested that the largest differences in canopy characteristics between tropical and temperate …


Foraging Behaviour And Intake In Temperate Cultivated Grasslands, S. Prache, J. L. Peyraud Oct 2021

Foraging Behaviour And Intake In Temperate Cultivated Grasslands, S. Prache, J. L. Peyraud

IGC Proceedings (1977-2023)

In temperate areas, grazing provides a large part of the nutrient requirements of ruminants and may be an important form of land use. In Europe, grassland occupies some 150 million hectares, and grazing provides about 60 to 75% of the nutrient requirements of cattle (Wilkins and Vidrih 2000). From the end of the 80’s, agricultural surpluses in Europe have led to production quotas and increased interest in more extensive systems. At the beginning of the 90’s, the emergence of the notion of sustainable agriculture combining economic, social (concerns in dereliction of less-favoured rural areas), and environmental issues (pollution, loss of …


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 (1977-2023)

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.