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Intensive Continuous Dairy Cows Grazing Of An Heterogeneous Grassland: Botanical Evolution In Relation With The Animal Behavior, Anne Mathieu, B Leclerc, J L. Fiorelli, B Jeannin, B Hubert, E de Vaubernier 2025 INRA

Intensive Continuous Dairy Cows Grazing Of An Heterogeneous Grassland: Botanical Evolution In Relation With The Animal Behavior, Anne Mathieu, B Leclerc, J L. Fiorelli, B Jeannin, B Hubert, E De Vaubernier

IGC Proceedings (1977-2023)

Intensive continuous grazing is now well established in tem­perate climate countries (Parker, 1987). In semi-continental cli­mate, the adjustment of stocking rate to herbage growth is more complex (Mathieu and Jeannin, 1986). Moreover parcels are very often an assemblage of different types of permanent meadows. The question of animal behaviour in relation to this spatial heterogeneity, and the subsequent evolution of the pas­ture was posed. The perenniality of this grazing system is dependent on the trend of this evolution. An experimentation was carried out in the northeastern France (Mirecourt, Vosges) by INRA, in order to analyse spa­tial choices made by dairy …


Consommation Par Des Caprins De Quercus Ilex Et Quercus Pubescens Dans Un Taillis Mediterraneen, M C. Leouffre, E Lecrivain, B Leclerc 2025 INRA

Consommation Par Des Caprins De Quercus Ilex Et Quercus Pubescens Dans Un Taillis Mediterraneen, M C. Leouffre, E Lecrivain, B Leclerc

IGC Proceedings (1977-2023)

Abandonnes depuis une cinquantaine d'annees, Jes massifs forestiers du sud-est de Ia France s'embroussaillent, Jes risques d'incendie augmentent alors que des eleveurs caprins a la recherche de ressources fourrageres pour !es troupeaux sont prets a utiliser ces milieux, done a participer a leur entretien. Afin de bien gerer l'espace et de controler )'impact des caprins, une etude a ete effectuee sur la consommation des deux principales especes ligneuses des taillis mediterraneens.


Composition Botanique Du Regime Alimentaire Des Bovins, Ovins Et Caprins Exploitant Des Parcours Naturels Et Agropastoraux Du Senegal, H Guerin, D Richard, D Froit, N Mbaye, C Sall 2025 IEMVT-CIRAD

Composition Botanique Du Regime Alimentaire Des Bovins, Ovins Et Caprins Exploitant Des Parcours Naturels Et Agropastoraux Du Senegal, H Guerin, D Richard, D Froit, N Mbaye, C Sall

IGC Proceedings (1977-2023)

La description botanique du regime ingere par !es ruminants au paturage peut resulter de methodes tres precises de terrain (Bourbouze, 1980) et de laboratoire (Theurer et al, 1976) ou au contraire d'une approche qualitative consistant a classer !es especes en fonction de leur appetibilite. La methode conc;ue pour cette etude a une precision intermediaire. Elle visait a fournir rapidement des informations sur !'utilisation des fourrages de parcours naturels saheliens (Vindou Tiengoli - 200 ha) OU sahelo-soudaniens (Doli - 740 ha) clotures et de parcours agrospastoraux soudaniens (Thysse Kayemor-terroir de 10.000 ha environ) ou soudano-guineens (Kolda-terroir de 3.000 ha) (carte 1).


The Effect Of Cutting And Goat Grazing On The Structure And Function Of Maqui Rangelands In Israel, A Perevolotsky 2025 The Volcani Center

The Effect Of Cutting And Goat Grazing On The Structure And Function Of Maqui Rangelands In Israel, A Perevolotsky

IGC Proceedings (1977-2023)

The Maqui, a vegetation form composed of evergreen shrubs and small trees with sclerophyllous leaves, dominates the Mediterranean Basin. In recent decades the Maqui ecosystem has been recovering from centuries of overexploitation and often develops into a dense thicket. Developing a proprer man­agement scheme for the Maqui ecosystem has become, there­fore, a challenge in many Mediterranean countries. Among the methods suggested to keep dense Maqui open and restore the balance· between the growing woody component and the herbaceous biomass, was the use of goats, which have gained fame as efficient browsers (e.g., Huss, 1971).


The Effect Of Grazing By Sheep And Kangaroos Upon The Survival Of Grasses In A Semi-Arid Woodland Of South Eastern Australia, A C. Grice 2025 NSW Agriculture

The Effect Of Grazing By Sheep And Kangaroos Upon The Survival Of Grasses In A Semi-Arid Woodland Of South Eastern Australia, A C. Grice

IGC Proceedings (1977-2023)

Since settlement by Europeans, the vegetation of the semi­arid woodlands of south eastern Australia has undergone major changes. The change of greatest significance to pastoral industries has been the increase in woody species and the decline of endemic perennial grasses (Anon, 1969). One cause of change has been grazing by large numbers of sheep, the introduced rabbit and the increased populations of kangaroos (Wilson et al., 1984; Newsome, 1975). Grazing-induced changes have meant not only the reduction in a valuable forage component but reduced competition for small shrub seedlings and a lowered probability of fires that kill shrubs. (Harrington et …


Evolution Et Degradation D'Un Ecosysteme Pature En Zone Soudano-Guineenne Au Cameroun, G Rippstein 2025 IEMVY/CIRAD

Evolution Et Degradation D'Un Ecosysteme Pature En Zone Soudano-Guineenne Au Cameroun, G Rippstein

IGC Proceedings (1977-2023)

L'Adamaoua est un vaste plateau situe en Afrique Centrale entre Jes 6° et 8° de latitude nord et Jes 10° et 16° de longitude est a des altitudes comprises entre 900 et I 500 m. Le climat y est soudanien avec une saison des pluies de 7 a 9 mois et I 600 a 1 800 mm de precipitation. Les observations foites en station ont montre des modifica­tions relativement foibles de la contribution des especes et des biomasses avec Jes feux, le paturage, Jes chargements moderes, Jes systemes d'exploitation et Jes repos periodiques frequents (Rippstein, 1985). Nous rapportons ici Jes …


Human And Animal Impacts On Vegetation And Forage Plants In The Southern Guinea Savanna Of Nigeria, L C. Nwaigbo 2025 Rivers State University of Science And Technology, Nigeria

Human And Animal Impacts On Vegetation And Forage Plants In The Southern Guinea Savanna Of Nigeria, L C. Nwaigbo

IGC Proceedings (1977-2023)

Human beings and animals interact with their habitat. This interaction changes the structure of the organization of com­munities of plants. The region that has been changed for worst with tress being replaced by grasses as a result of burning is the Savanna region of Nigeria. Annual fire is a common occurence in Nigerian Savanna and this ecological factor has altered the original vegetation of these areas. Burning is usually undertaken for clearing land for culti­vation and also for production of a flush of fresh palatable grass for grazing by the nomadic cattle herdsmen. Forage plants like Afzelia africana, Pterocarpus erinaceus …


Utilisation Sylvopastorale De L'Espinal (Acacia Caven) Dans L'Aire Climatique Mediterraneenne Du Chili. Influence De L'Arbre Sur La Vegetation Pastorale, C Ovalle, J Avendano 2025 Estacion experimental Quilamapu

Utilisation Sylvopastorale De L'Espinal (Acacia Caven) Dans L'Aire Climatique Mediterraneenne Du Chili. Influence De L'Arbre Sur La Vegetation Pastorale, C Ovalle, J Avendano

IGC Proceedings (1977-2023)

L'espinal constitue d'une strate ligneuse dominee par l'arbre autochtone, Acacia caven, et d'une strate herbacee dominee par ��es therophytes d'origine circummediterraneenne, est la forma­tion vegetale pastorale d'importance economique majeure du Chili mediterraneen. L'amelioration pastorale de l'espinal, du fait de la presence simultanee des deux strates de vegetation, se heurte toujours a la question de la place, de !'utilisation ou du role d' Acacia caven par rapport a la strate herbacee dans le systeme ecologique complexe. Une premiere partie des resultats sur !'influence de l'arbre a ete presentee par Ovalle (1986) et Ovalle et Aven­dano (1987). Cette contribution ajoute des resultats …


Grazing Pressure By Sheep: Consequences For Pasture Stability In An Australian Mulga Woodland, K C. Hodgkinson, J W. Terpstra 2025 CSIRO

Grazing Pressure By Sheep: Consequences For Pasture Stability In An Australian Mulga Woodland, K C. Hodgkinson, J W. Terpstra

IGC Proceedings (1977-2023)

The mulga woodlands are an extensive (1.6 km2) native pas­ture type in semi-arid and arid Australia and mainly utilised for wool production (merino sheep). The dominant shrub/treee species is mulga (Acacia aneura) which usually occurs in groves across slopes. Pastures comprise perennial grasses and ephem­eral forbs. Continuous grazing by sheep and cattle and fire suppression has led to widespread degradation of these pastures; perennial grasses have diminished in abundance and been replaced by ephemeral forbs and inedible shrubs. This paper reports the grazing pressure on Thryridolepis mit­chelliana (a perennial grass ubiquitous in mulga woodlands but commonly diminished in abundance) …


Buried Viable Seeds In The Alberta Foothills Under High Intensity Low Frequency Grazing And The Resemblance To Seed Rain, R Lagroix-Mclean, Jane R. King 2025 University of Alberta

Buried Viable Seeds In The Alberta Foothills Under High Intensity Low Frequency Grazing And The Resemblance To Seed Rain, R Lagroix-Mclean, Jane R. King

IGC Proceedings (1977-2023)

Sudies describing seed banks and seed rain on native rangelands are few in number although it is recognized that there is an abundance of viable seed within the soil (Rabinowitz, 1981; Johnston et al., 1969). The seed bank and seed rain represent an integral part of the potential for recruit­ment or regeneration of species into the sward (Rabinowitz, 1981). The role of seed banks in succession is yet to be com­pletely understood. Field experiments were conducted to describe seed bank and seed rain on a Canadian native prairie and to evaluate the impact of high intensity low frequency graz­ing on …


The Structure Of The Grass/Clover Sward And Its Implications In Sward Management, Alison Davies 2025 AFRC

The Structure Of The Grass/Clover Sward And Its Implications In Sward Management, Alison Davies

IGC Proceedings (1977-2023)

In attempting to formulate management rules for perennial ryegrass/white clover pastures it is important to try to dis­tinguish between changes in clover content which result from management, and those which result from the different responses of grass and clover to the changing environment. This paper discusses the similarities and differences between the response patterns of components of growth in grass and clover and attempts to show how the differences between the two species my be exploited to control the balance between them.


Effets Du Pietinement Des Bovins Sur Le Trefle Blanc Pur Ou En Association, Francoise Vertes 2025 INRA

Effets Du Pietinement Des Bovins Sur Le Trefle Blanc Pur Ou En Association, Francoise Vertes

IGC Proceedings (1977-2023)

Le pietinement des bovins en mauvaises conditions de por­tance, !ors du dernier paturage d'automne ou de la mise a l'herbe au printemps, etant le principal facteur de deterioration de la structure des sols (Lauden, 1986), nous en avons etudie Jes effets sur Jes plantes et Jes sols, a l'echelle stationnelle, en Breta­gne. Une double demarche analytique et synthetique permet de quantifier a court et moyen terme Jes consequences directes et indirectes du pietinement (Morion,. 1983). Une premiere experimentation (1987) concerne un pietine­ment de printemps, plus ou moins intense; la deuxieme (1987-1988) integre Jes effets d'un pietinement d'hiver, cumule ou non …


Changes Under Sheep Grazing In The Species Composition Of Sown Pastures With Special Reference To White Clover, J Gajda, M Warda, J Sawicki, Anna Kotakowska 2025 Academy of Agriculture

Changes Under Sheep Grazing In The Species Composition Of Sown Pastures With Special Reference To White Clover, J Gajda, M Warda, J Sawicki, Anna Kotakowska

IGC Proceedings (1977-2023)

White clover is a valuable component of pasture (Thomson, 1978). The level of nitrogen fertilization and the method of pas­ture utilization (Mackenzie, 1982), as well as habitat conditions (Lenoble, 1975) have a decided effect upon the persistence of this species in the sward. However, the stability of white clover in the sward is a complex problem and further studies are required. This paper records changes in the species composition of pasture sward caused by sheep grazing with special reference to white clover.


Variation With Season And Node Position In Carbohydrate Content Of White Clover Stolons, M.J M. Hay, A.C P. Chu, M V. Knighton, S Wewala 2025 DSIR

Variation With Season And Node Position In Carbohydrate Content Of White Clover Stolons, M.J M. Hay, A.C P. Chu, M V. Knighton, S Wewala

IGC Proceedings (1977-2023)

Storage of carbohydrate in stolon of field-grown white clover (Trifolium repens L.) is important as up to 60 % of dry matter is in stolons and their carbohydrate content is high relative to roots (Harris et al., 1983). Previously no account has been taken of node position when the carbohydrate status of stolons has been assessed. Most field-grown white clover is clonal, with older nodes continually dying as new nodes are formed, hence the pattern of carbohydrate storage of individual nodes may differ. The objectives of this study were to determine the carbo­hydrate status of individual nodes at different …


Simulation Of The Effect Of Stolon Death Rates On Branching Structure Of White Clover Plants, V J. Thomas, M.J M. Hay, P.C D. Newton 2025 DSIR

Simulation Of The Effect Of Stolon Death Rates On Branching Structure Of White Clover Plants, V J. Thomas, M.J M. Hay, P.C D. Newton

IGC Proceedings (1977-2023)

Simulation is a technique whose value is greatest in two areas. The first of these involves the discipline of examining the system being modelled, and, as a result, being forced to obtain accurate information on the parameters which significantly influence the system. The second area involves estimating the effect of changes in system parameters, and from this establish­ing which factors have substantial effects on the output vari­ables considered. In the model of white clover growth considered here a con­siderable number of input parameters were used. These parameters were derived from data of variable reliability. In particular, the death rate data …


Grazing Management Effects On Perennial Ryegrass And White Clover Triller Populations, W F. Hunt 2025 DSIR

Grazing Management Effects On Perennial Ryegrass And White Clover Triller Populations, W F. Hunt

IGC Proceedings (1977-2023)

Pasture grazing managements have clearly identifiable effects on plant morphology, density and species composition. Typ­ically, swards grazed continuously by sheep have relatively high populations of relatively small perennial ryegrass tillers while rotationally grazed swards contain rather fewer large/ tillers (Chapman and Clark 1984, Suckling 1959, Mitchelle and Glen­day 1958, Collet et al., 1981). Generally, more severe defoli­ations are associated with greater tiller densities (Davies 1977). Management induced increases in tiller populations of per­ennial pastures are possible because plants tiller freely when competition for light is reduced by herbage removal (Hunt and Field 1978). If left undisturbed, tiller density is finally …


Manipulating The Plastic Response Of White Clover Through Grazing, In A Cool, Temperate Climate In New Zealand, R.J M. Hay, G S. Baxter 2025 DSIR

Manipulating The Plastic Response Of White Clover Through Grazing, In A Cool, Temperate Climate In New Zealand, R.J M. Hay, G S. Baxter

IGC Proceedings (1977-2023)

In Southland, New Zealand, a wide range of grazing systems are practised, from continuous set-stocking to year round rot­ational grazing. A problem is the apparent decline in contri­bution of white clover (Trifolium repens L.) to total sward pro­duction in older pastures. Cereal and brassica crops, which depleted soil N, were traditionally sown each year and used to ensure that about 20 % of any farm consisted of clover-domi­nant two and three year old pastures. Carran (pers. comm.) suggests that all-grass-farming has removed the N-deficit incentive for clover growth. Farmlet tri­als at the Gore Regional Station, DSIR, have shown that …


Characteristics Of Individual White Clover Plants In Grazed Swards, M J.M Hay, J L. Brock, V J. Thomas 2025 DSIR

Characteristics Of Individual White Clover Plants In Grazed Swards, M J.M Hay, J L. Brock, V J. Thomas

IGC Proceedings (1977-2023)

Compared to the large volume of agronomic research on white clover (Trifolium repens L.), studies on the growth and morphology of individual plants constituting the population under grazing are few (Brock et al., 1988). Increased knowledge of the clonal growth and seasonal behaviour of individual white clover plants is seen as essential (Snaydon, 1985) if the mechanisms governing persistence and productivity in mixed grazed swards are to be understood. Seasonal growth patterns of white clover vary with environment (Jones, 1982) and this paper describes seasonal variation in some characteristics of individual white clover plants in grazed swards in a temperate …


The Influence Of Physical And Biochemical Characteristics Upon The Selection Of White Clover By Grazing Sheep, J Hodgson, D A. Clark, S Wewala 2025 Massey University

The Influence Of Physical And Biochemical Characteristics Upon The Selection Of White Clover By Grazing Sheep, J Hodgson, D A. Clark, S Wewala

IGC Proceedings (1977-2023)

Observations have been made on the reactions of sheep to variations in leaf mark (Cahn and Harper, 1976) and cyanogenic glucoside concentration (Corkill, 1952) in white clover (Trifolium repens L.), but little is known about the rela­tive importance of alternative visual and biochemical cues in selective behaviour under grazing conditions. This paper reports the results of two studies at DSIR Grasslands Division, Palmerston North, New Zealand on the reactions of grazing sheep to white clover plants exhibiting substantial genotypic variation in leaf size and colour, leaf mark, and cyanogenic glucoside potency.


Interactions Between Parent Stolons And Branches In Assimilate Partitioning In White Clover (Trifolium Repens L.), D F. Chapman, M J. Robson, R W. Snaydon 2025 The University of Reading

Interactions Between Parent Stolons And Branches In Assimilate Partitioning In White Clover (Trifolium Repens L.), D F. Chapman, M J. Robson, R W. Snaydon

IGC Proceedings (1977-2023)

In temperate regions of the world, white clover (Trifolium repens L.) persists in permanent pastures by vegetative repro­duction (Chapman 1987). Thus stolon branching is vital for the perennation of the species. There is, however, no information available on physiological relationships between branches and parent stolons, or on the degree of physiological integration of whole clover plants. Clover spreads laterally by stolon exten­sion and in extremely heterogenous environments, like grazed pastures, parts of a single plant may encounter different levels of stress (defoliation, nutrient levels, shading). Physiological integration (eg. mutual exchange of carbohydrate between branches and parent stolon) may allow …


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