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Protocol For Assessing And Managing Radon Gas Exposure Risks In Caves: A Case Study Of Altamira And Paleolithic Cave Art Of Northern Spain World Heritage Site, Sergio Sanchez-Moral, Javier Lario, Soledad Cuezva, Juan Carlos Cañaveras, Tamara Martín-Pozas, Angel Fernández-Cortés Oct 2025

Protocol For Assessing And Managing Radon Gas Exposure Risks In Caves: A Case Study Of Altamira And Paleolithic Cave Art Of Northern Spain World Heritage Site, Sergio Sanchez-Moral, Javier Lario, Soledad Cuezva, Juan Carlos Cañaveras, Tamara Martín-Pozas, Angel Fernández-Cortés

International Journal of Speleology

Exposure to radon and its progeny poses a significant health risk for workers in tourist caves. Implementing protective measures is challenging due to increasingly strict gas concentration and dose limits in new regulations. This study evaluates the annual effective radiation doses received by workers and researchers, considering seasonal and spatial radon variability. Radon levels, temperature, and ventilation patterns were continuously monitored for at least one year in each cave. Results show significant radon fluctuations influenced by seasonal ventilation regimes driven by thermal gradients between the cave and external atmosphere. Using International Commission on Radiological Protection guidelines, the study calculates the …

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Predicting Species Assemblages At Wildlife Crossing Structures Using Multivariate Regression Of Principal Coordinates, Thomas J. Yamashita, Daniel G. Scognamillo, Kevin W. Ryer, Richard Kline, Michael E. Tewes, John H. Young Jr., Jason V. Lombardi Oct 2025

Predicting Species Assemblages At Wildlife Crossing Structures Using Multivariate Regression Of Principal Coordinates, Thomas J. Yamashita, Daniel G. Scognamillo, Kevin W. Ryer, Richard Kline, Michael E. Tewes, John H. Young Jr., Jason V. Lombardi

School of Earth, Environmental, & Marine Sciences Faculty Publications

Wildlife populations are in decline due to human threats, including highways. Strategies for reducing road impacts on wildlife include wildlife fencing which keep animals off roads and wildlife crossing structures (WCSs) which provide safe passage across roads. Wildlife crossing structures are diverse and transportation managers are often interested in identifying which WCS designs are effective for target species so a model that predicts target species usage of WCSs is likely to be beneficial to managers and biologists. Wildlife crossing structures are typically built for select species but are utilized by other species, so it may be beneficial to examine WCS …

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Grasslands For Our World, F Riveros Oct 2025

Grasslands For Our World, F Riveros

IGC Proceedings (1977-2023)

The present-day role of grasslands and fodder is reviewed with respect agriculture, animal production and environmental concerns. The world's grazing lands are a finite resource and, overall, arc being badly managed; in most developing countries action is required now, before it is too late. They will continue to be a major source of animal feed for the foreseeable future; encroachment from cropping will continue locally but, for much of what is now natural pasture, exploitation by the grazing animal .will remain the major means of obtaining an economic return; the task of grassland professionals is to assist the managers of …

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The Feeding Value Of Forages, C Demarquilly Oct 2025

The Feeding Value Of Forages, C Demarquilly

IGC Proceedings (1977-2023)

The lower productivity of legume based swards and their instability of yield from year to year compared with nitrogen fertilised grass swards continues to be a major constraint on the integration of leguminous nitrogen fixing species into present-day farming systems. Most legume systems have a high biological nitrogen fixation (BNF) potential which is rarely attained in the· field due to limiting environmental or management factors. Enhancement of BNF through manipulation of the Rhizobium and plant components of the symbiosis must be viewed as a long-term objective. Optimisation of nitrogen fixation in the short-term may best be achieved through optimisation of …

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Nitrogen Fixation, Cycling, And Utilization, P M. Murphy, M T. Sherwood Oct 2025

Nitrogen Fixation, Cycling, And Utilization, P M. Murphy, M T. Sherwood

IGC Proceedings (1977-2023)

The lower productivity of legume based swards and their instability of yield from year to year compared with nitrogen fertilised grass swards continues to be a major constraint on the integration of leguminous nitrogen fixing species into present-day farming systems. Most legume systems have a high biological nitrogen fixation (BNF) potential which is rarely attained in the· field due to limiting environmental or management factors. Enhancement of BNF through manipulation of the Rhizobium and plant components of the symbiosis must be viewed as a long-term objective. Optimisation of nitrogen fixation in the short-term may best be achieved through optimisation of …

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Development Of Legume-Based Pastures For Livestock Production In Yunnan, Peoples Republic Of China- Preliminary Studies With Trifolium Semiplosum Cv. Safari And Temperate Legume Cultivars, M J. Mathison, M/S T. Wang, Z Y. Yang, M H. Dunning, Y N. Al, Z Z. Ma, H X. Al, L W. Peng, H Yang, D C. Zhang, C G. Zhang, G R. Yang Oct 2025

Development Of Legume-Based Pastures For Livestock Production In Yunnan, Peoples Republic Of China- Preliminary Studies With Trifolium Semiplosum Cv. Safari And Temperate Legume Cultivars, M J. Mathison, M/S T. Wang, Z Y. Yang, M H. Dunning, Y N. Al, Z Z. Ma, H X. Al, L W. Peng, H Yang, D C. Zhang, C G. Zhang, G R. Yang

IGC Proceedings (1977-2023)

Aiming to improve livestock production from extensive grassland areas in Yunnan Province south west China, forage cultivar evaluation experiments are in progress as part of the China-Australia Technical Co-operation Programme. Preliminary results are given from introduced temperate legumes sown in 1983 in replicated swards in cultivated and uncultivated grassland. South west monsoon climates sampled range from alpine-temperate to tropical. In alpine sites red clover and annual species e.g. vetches, persian and subterranean clovers were among top dry matter yielders in the first year on cultivated land, Annual clovers failed or were outyielded by white, red clovers and, in one locality, …

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Preliminary Fertilizer Requirements For Establishing Legume Based Pastures In The Alpine Zoone Of Yunnan, Jinjing Wang, J R. Bruce-Smith, Jixin Li, Mingliang Wang Oct 2025

Preliminary Fertilizer Requirements For Establishing Legume Based Pastures In The Alpine Zoone Of Yunnan, Jinjing Wang, J R. Bruce-Smith, Jixin Li, Mingliang Wang

IGC Proceedings (1977-2023)

Preliminary results of field trials designed to assess the soil fertility status for establishing improved legume based pastures in the alpine zone of Yunnan Province are presented. These trials were undertaken by a joint Chinese-Australian Project which is investigating ways to improve the livestock industry of the Province. The best treatments at one site in the North East yielded about 9000kg of total (grass + legume + weeds) pasture and 7000kg of this was attributable to clover production. At another site in the North West on the Southern Tibetan Plateau summer waterlogging confined the pasture yield to 4000kg DM. Tentative …

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Preliminary Studies Of Fertilizer Requirements Of Tropical Legumes In Southern Yunnans Red River Valley, Jinjing Wang, J R. Bruce-Smith, Mingliang Wang, Jixin Li Oct 2025

Preliminary Studies Of Fertilizer Requirements Of Tropical Legumes In Southern Yunnans Red River Valley, Jinjing Wang, J R. Bruce-Smith, Mingliang Wang, Jixin Li

IGC Proceedings (1977-2023)

As part of a joint Chinese-Australian Project to promote livestock development, a farm site in the lower Chinese section of Red River Valley was chosen as an area to study techniques suited to meeting these objectives through establishing and utilizing legume based tropical pastures. Preliminary results of fertilizer trials at Daliuhu Farm show that sulphur deficiency is the main nutrient problem retarding the growth of siratro and stylo legumes. The application of as little as 5, but optimally between 10 and 20kg of sulphur as gypsum Sor elemental S seems to adequately meet their growth requirements. The apparent adequate phosphate …

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Sulfur Fertilization Of Five Tropical Forages Ii. Digestibility Of Dry Matter And Cell Wall Constituents, J E. Van Eys, S Ginting, H Pulungan, W L. Johnson Oct 2025

Sulfur Fertilization Of Five Tropical Forages Ii. Digestibility Of Dry Matter And Cell Wall Constituents, J E. Van Eys, S Ginting, H Pulungan, W L. Johnson

IGC Proceedings (1977-2023)

Four tropical grasses and one legume were fertilized with O or 60 kg S/ha. Leaves and stems of 6 and 9 weeks old regrowth were harvested seperately from replicated plots and used to study the effect of S fertilization on parameters of in vitro DM and NDF digestion. The overall effect of fertilization was negative and most pronounced for leaves. There were large differences among forages. DM digestibility at 48 h was reduced (P < .05) for fertilized guinea grass and setaria but NDF digestion at 96 h was only lower for guinea grass. DM digestibility of stems was not affected by fertilization but NDF disappearance of napier grass stems was decreased significantly. S fertilization had no effect on lag of NDF digestion but rate of NDF digestion for stems and leaves was reduced (P < .05) by fertilization. The effect was especially large for centro. It is suggested that the negative effects of S fertilization are associated with changes in the structural components of the forages and the source of the rumen inoculum.

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Sulfur Fertilization Of Five Tropical Forages I. Dry Matter Production And Chemical Composition, J E. Van Eys, S Ginting, M Rangjuti, W L. Johnson Oct 2025

Sulfur Fertilization Of Five Tropical Forages I. Dry Matter Production And Chemical Composition, J E. Van Eys, S Ginting, M Rangjuti, W L. Johnson

IGC Proceedings (1977-2023)

Four tropical grasses and one legume were grown on an oxic dystropept soil in W. Java, Indonesia. Two levels of S fertilizer were applied (0 and 60 kg S/ha). Forages were harvested at 6 and 9 week intervals during the wet and dry monsoons respectively. Production of leaves and stems was determined separately and samples of a 6- and 9-week regrowth were analyzed for chemical composition. The effect of S fertilization on dry matter (DM) yield was markedly influenced by the effect of season. During the wet season only the production of stems from napier grass was increased (P < .05). During the dry season stem and leaf production of napier grass and centro increased (P < .05) under fertilization but there was a decrease (P < .05) in leaf production of guinea grass. S fertilization increased S content in leaves and stems by 23%. There was a tendency for N to increase and for NDF in leaves to decrease. Only in centro was ADF and lignin of fertilized plants lower (P < .05). Although Ca, P, Mg, Cu and Zn were not affected by fertilization, ash content in leaves of fertilized forages differed (P < .05) from controls.

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Development And Evaluation Of Stylosanthes Pastures For Seasonally Dry Areas Of Queensland, Australia, B Walker, P J. Mckeague Oct 2025

Development And Evaluation Of Stylosanthes Pastures For Seasonally Dry Areas Of Queensland, Australia, B Walker, P J. Mckeague

IGC Proceedings (1977-2023)

There are 20.8 million hectares of the seasonally dry tropics and subtropics of Queensland to which the Stylosanthes spp. (stylos) are adapted. Only 600 000 hectares have been sown, or are naturalised, to these legumes, mainly to Townsville stylo (S. humilis). However, since 1974 anthracnose (Colletotrichum gloeosporioides) has severely affected Townsville stylo pastures, and newer cultivars of Stylosanthes are being used, viz: Verano (S. hamata), Seca and Fitzroy shrubby stylos (S. scabra) and Graham (S. guianensis var. guianensis). As little was known about the animal production and pasture stability associated with these stylos ( especially shrubby stylos) under …

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Review Of Forage/Livestock Production On Mixed Farms In Sahel West Africa, James R. Dickey Oct 2025

Review Of Forage/Livestock Production On Mixed Farms In Sahel West Africa, James R. Dickey

IGC Proceedings (1977-2023)

This is a review of forage and livestock production as they interact with farming in Sahel West Africa. Because of the complementarity of livestock and farming, as well as the abundant production of native forage in the higher rainfall southern farming areas, there is considerable hope among the donor community and host governments that both livestock and crop production can be substantially increased in the Sudan zone of West Africa. According to Winrock (1978) crop residue provides 24 % of the world supply of ruminant nutrients .. On the other hand, livestock manure supplies a large part of the agricultural …

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Forage Research In Morocco And Approach To Face Constraints In A Developing Country, G Jaritz, M Bounejmate Oct 2025

Forage Research In Morocco And Approach To Face Constraints In A Developing Country, G Jaritz, M Bounejmate

IGC Proceedings (1977-2023)

Forage production is of a iow level in Morocco because of socio-economic and technical constraints in spite of its potential functions to integrate animal husbandry into cropping systems and to prevent soil degradation. An approach to applied forage research is described which takes into account the existing constraints including the suboptimal functioning of the present extension service. It combines small plot experimentation with commercial field testing on livestock farms owned by a number of development organizations and influential farmers in different edapho-climatic regions. In this way, pilot units for demonstration, economic analysis and convincing of decision makers are created and …

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Economics Of Producing Corn (Maize) And Sorghum As Feeds For Animal Production In China, Bingxing Zhang Oct 2025

Economics Of Producing Corn (Maize) And Sorghum As Feeds For Animal Production In China, Bingxing Zhang

IGC Proceedings (1977-2023)

Due to insufficient production of animal products the Chinese people have eaten too much grain and too little meat and milk. Now, as a result of burriper harvests for several years in succession, it is time for the Chinese peasants to convert their surplus grain into feeds for the development of animal production to meet the growing needs of the Chinese people for meat and milk on the one hand and for wool and leather on the other. At the same time more forage sorghum and corn should be grown, especially on unused or misused poor lands and wide hillsides …

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Loss Of Nutrients In Surface Runoff From Grassland Treated With Pig Slurry, M Sherwood Oct 2025

Loss Of Nutrients In Surface Runoff From Grassland Treated With Pig Slurry, M Sherwood

IGC Proceedings (1977-2023)

Soil physical limitations and climatic conditions in some countries make landspreading of manures a potential environmental hazard due to the danger of surface runoff to waterways. Pig slurry at two application rates was spread on sloped grassland plots at three sites with different soil drainage properties. All surface runoff water was collected and analysed after each significant rainfall. At Sites 1 and 2 where the first runoff event occurred within 48 hours of spreading, the runoff water contained very high concentrations of nitrogen (N), phosphorus (P), potassium (K) and BOD (Biochemical Oxygen Demand), which were related to the rate of …

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Yield And Regrowth Characteristics Of Alfalfa Grazed By Sheep In Spring And Summer, V G. Allen, D D. Wolf, J P. Fontenot Oct 2025

Yield And Regrowth Characteristics Of Alfalfa Grazed By Sheep In Spring And Summer, V G. Allen, D D. Wolf, J P. Fontenot

IGC Proceedings (1977-2023)

Grazing alfalfa (Medicago sativa, L.) would provide high quality pasture in animal production systems. The influence of grazing alfalfa with sheep in early spring or in summer on regrowth characteristics, weed encroachment, and subsequent yields was investigated during two years and on hay yields during year 3 with no grazing imposed. Alfalfa was grazed in spring for 0, 2, 4, and 6 weeks at two grazing pressures: light (LAI of 1.0) and heavy (LAI< 0.5). Non-grazed alfalfa was harvested at late bud stage. Regrowth on all systems was harvested at 1/10 bloom. Grazing for 6 weeks reduced subsequent hay yield only in year 2. Heavy grazing pressure increased weed encroachment but weeds were effectively controlled with herbicides. Few residual effects were measurable in year 3. Another planting of alfalfa was grazed in summer following two hay cuts by five systems: 1), 2), and 3) grazed about 14 days after second hay cut for 2, 4, and 6 weeks, respectively; 4) grazed at early bud stage for 7-10 days; 5) grazed at early bloom for 7 days. For system 6, alfalfa was not grazed and hay was cut at 1/10 bloom. Following grazing, hay was cutif regrowth reached 1/10 bloom stage. Grazing for 2, 4, and 6 weeks linearly decreased fall regrowth and increased weed encroachment. In year 3, yield was reduced by grazing except at early bloom but differences were slight by August. Weed encroachment tended to increase with grazing duration. These data indicate that alfalfa is more tolerant of grazing in spring than summer. If weeds are controlled, extended grazing durations appear possible.

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Seasonal Distribution Of A Fungal Endophyte In Tall Fescue Pastures, D P. Belesky, O J. Devine, S R. Wilkinson, J A. Stuedemann, D M. Hildreth Oct 2025

Seasonal Distribution Of A Fungal Endophyte In Tall Fescue Pastures, D P. Belesky, O J. Devine, S R. Wilkinson, J A. Stuedemann, D M. Hildreth

IGC Proceedings (1977-2023)

The presence of a fungal endophyte (Acremonium coenophialum) in tall fescue (Festuca arondinacea) and high nitrogen (N) fertilizer input, has been associated with tall fescue toxicosis symptoms in beef cattle. Expression of toxicosis symptoms vary with season, however the dynamics of endophyte levels in a tall fescue over a growing season have not been described. Our study characterizes seasonal distribution of the endophyte in grazed fescue swards as influenced by cultivar and N fertilizer over two years (1983 and 1984). Three replicate 0.7 ha paddocks of 'Johnstons', 'Triumph' and 'KY-31' (low and high endophyte status; and 134 …

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Preliminary Report On Experiment Of Winter Rotational Grazing Of Local Cattle, Lu Wengao, Lai Zhiqiang Oct 2025

Preliminary Report On Experiment Of Winter Rotational Grazing Of Local Cattle, Lu Wengao, Lai Zhiqiang

IGC Proceedings (1977-2023)

In winter, grass growth declines sharply and animal's demand increases with the passage of time. In Dec., affected by frostbite and low temperatures, pasture output drops greatly and cannot meet the needs of cattle. For this reason, in Nanning, late Dec. is considered the winter grazing in a critical period (WGCP). Huts and shelters should be put up in the areas where animals should continue to graze throughout the winter. It is relatively economical to give animal supplementary feeding started in late Dec.

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Behavioral And Physiological Characteristics Of Misaki Horses As Adapted To Their Winter Habitats, Y Kaseda, E Yamaguchi Oct 2025

Behavioral And Physiological Characteristics Of Misaki Horses As Adapted To Their Winter Habitats, Y Kaseda, E Yamaguchi

IGC Proceedings (1977-2023)

Few informations have been found on the metabolic adaptation of domestic animals to their winter circumstances. The present study was conducted to make clear the behavioral and physiological characteristics of Misaki horses living under semi-wild condition as adapted to their winter habitats. Nine 24 hour consecutive observations were made from 1983 to 1984, and simultaneously heart rate (beatd per min.), rectal temperature and ambient temperature were recorded at the intervals of 30 min .. Horses were frequently found to graze and rest in the forests or on south-facing weedy grasslands in winter. Time budget of a day changed seasonally and …

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Alternative For Managing Beef Yearlings After Intensive Early Stocking Of Kansas Flint Hills Range, G L. Posler, G M. Ward, J G. Riley, C E. Owensby, E F. Smith, K K. Bolsen, R M. Helsel, N S. Hill Oct 2025

Alternative For Managing Beef Yearlings After Intensive Early Stocking Of Kansas Flint Hills Range, G L. Posler, G M. Ward, J G. Riley, C E. Owensby, E F. Smith, K K. Bolsen, R M. Helsel, N S. Hill

IGC Proceedings (1977-2023)

Intensive early stocking of Kansas Flint Hills tall grass prairie (2X normal rate during the first half of the grazing season) has produced greater beef/ha than season -long stocking because of low animal gains during the last half season. Alternatives for animals removed from native range in mid-July include grazing seeded forages such as alfalfa or hybrid sudangrass or direct placement to the feedlot. During 3 years, we compared grazing alfalfa or hybrid sudangrass during the last half season and subsequentfeedlot placement for finishing with placement directly to the feedlot in mid-July. In our studies, animal gains were better for …

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The Effect Of Stocking Rate And Grazing Management Upon Ewe Liveweight, Ewe Fertility, Lamb Growth And Pasture Production On Subterranean Clover Based Pasture In Western Australia, H Lloyd Davies, I N. Southey Oct 2025

The Effect Of Stocking Rate And Grazing Management Upon Ewe Liveweight, Ewe Fertility, Lamb Growth And Pasture Production On Subterranean Clover Based Pasture In Western Australia, H Lloyd Davies, I N. Southey

IGC Proceedings (1977-2023)

Border Leicester x Merino ewes joined to Dorset Hom rams were run at 3 stocking rates (S.R.) and 2 systems of pasture management, viz Continuous grazing (C.G.) or a 4 sub-plot Deferred grazing system (D.G.) designed to meet the needs of the breeding ewe on subterranean clover based pastures at Bakers Hill (32°S l17°E), Western Australia for three years. Stocking rate affected ewe liveweight at joining and lambing, the growth of single lambs in the first year and tended to reduce the growth rate of twin lambs. It profoundly affected the amount of dry matter of pasture on offer. The …

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The Preliminary Study On Optimum Stocking Rate In Alpine Meadow, Nanlin Pi, Xingmin Zhou, Xinquan Zhao Oct 2025

The Preliminary Study On Optimum Stocking Rate In Alpine Meadow, Nanlin Pi, Xingmin Zhou, Xinquan Zhao

IGC Proceedings (1977-2023)

In a grazing trial with Tibetan sheep at Haibei Research Station of Ecosystem, the relationships between stocking rate, live-weight gain per animal and live-weight gain per ha were studied in a Kobresia humilis meadow pasture. Stocking rates were 2.14 (A), 3.12 (B), and 6.07 (C) animal/ha. Grazing was rotated in a summer-autumn pasture (from July to October) and in a winter-spring pasture (from November to June of next year). Under different stocking rates, changes in horizontal and vertical plant community composition have taken place. The decreases of live-weight gain per animal and of herbage yield with increased stocking rate were …

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Relating Profit To Quantity Of Standing Herbage In Grazing Intensity Studies, David I. Bransby, B E. Conrad Oct 2025

Relating Profit To Quantity Of Standing Herbage In Grazing Intensity Studies, David I. Bransby, B E. Conrad

IGC Proceedings (1977-2023)

Previous economic analyses of grazing intensity studies have related profit to stocking rate. However, no information is available on the relationship between profit and kg standing herbage ha-1. In this paper the objective is to relate profit ha-1 to standing herbage. Coastal bermudagrass continuously grazed with beef steers at four grazing pressures is used as an example. Average daily gain and animal grazing days ha-1 were linearly related to standing herbage (r = 0.95 and 0.99). The resultant regression equations were used to relate beef gain ha-1 to standing herbage. This function in tum was used to relate profit ha-1 …

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Influence Of Stocking Rate On The Plant-Animal Interface In Rotational Grazed Mixed Swards, J W. Stuth, J R. Brown, P D. Olson, M R. Araujo Oct 2025

Influence Of Stocking Rate On The Plant-Animal Interface In Rotational Grazed Mixed Swards, J W. Stuth, J R. Brown, P D. Olson, M R. Araujo

IGC Proceedings (1977-2023)

The impacts of brief periods of intense grazing in multipasture-single herd grazing systems on critical plant and animal parameters in natural mixed swards are not well understood. It was our objective to determine the interrelationship and nutritional consequence of tiller defoliation intensity, selection ratio and diet composition of two codominant species with contrasting phenology and growth habit as stocking rate was increased. A 16-pasture, 1-herd short-duration grazing regime was simulated at four stocking rates on a little bluestem (Schizachyr­ium scoparium)-brownseed paspalum (Paspalum plicatulum) savannah. Variables measured included morphology and defoliation intensity of marked tillers, diet composition …

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Modeling Of Beef-Forage Grazing Interactions, O J. Loewer, K L. Taul, L W. Turner, N Gay, R Muntifering Oct 2025

Modeling Of Beef-Forage Grazing Interactions, O J. Loewer, K L. Taul, L W. Turner, N Gay, R Muntifering

IGC Proceedings (1977-2023)

The key to more efficient production of beef from forages is in matching animal intake and plant growth. One method of evaluating the interaction of grating animals and growing forages is through dynamic computer simulation models. A model called GRAZE has been developed to evaluate this interaction. GRAZE incorporates previously developed plant and animal models with selective grazing logic based on the premise that beef animals maximize their digestible dry matter intake rate. The model subdivides the pasture int_o subareas. The subareas are grazed according to a priority system where the animal shifts from one subarea to another so as …

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Meeting Animal Needs From Mixed Grass-Legume Pastures, A J. Harris, D A. Clark Oct 2025

Meeting Animal Needs From Mixed Grass-Legume Pastures, A J. Harris, D A. Clark

IGC Proceedings (1977-2023)

Experiments measuring plant performance and animal production from sheep at 4 climatically diverse sites in New Zealand are described. In the southern South Island grazing patterns have been developed which minimize the effect of the winter pasture production trough and make best use of the high spring/summer growth rates. High yields of animal products are achieved. In Canterbury, summer moisture stress and cool winters can have far-reaching effects on pasture and, consequently, animal performance. Use of special-purpose pastures with complementary production rhythms has allowed high productivity to be achieved in dry land. On moist North Island hill country increased stocking …

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The Animal Factor In Pasture Studies, J A. Taylor Oct 2025

The Animal Factor In Pasture Studies, J A. Taylor

IGC Proceedings (1977-2023)

The challenge in plant-animal interface research is to derive meaningful plant-animal relationships. This paper examines some of the assumptions and bias in conventional grazing research practices. Variations within pasture and in the activity and distribution of grazing animals are important characteristics of most grazing situations. The conventional sampling strategies do not allow for the possibility that the animal perceives vegetation in a different or more subtle way than we perceive it. A more logical approach would be to seek patterns in animal activity and distribution and relate these to variations in herbage and site attributes. This approach would provide the …

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Maximizing Beef Production From Irrigated Pastures With Light Weight Steers, W W. Heinemann Oct 2025

Maximizing Beef Production From Irrigated Pastures With Light Weight Steers, W W. Heinemann

IGC Proceedings (1977-2023)

An experiment was designed to compare beef production by three successions of light weight steers continuous grazing two kinds of irrigated pastures. Two growth promotant ear implants were superimposed treatments in 1982. Successions of light weight steers were used in an effort to obtain maximum animal gain per ha, comparing rates of gain and gains per ha by trimesters. Average steer gains per ha from orchardgrass (Dactylis glomerata) and from perennial ryegrass (Lolium perenne) over a 4-year period were nearly the same. Average daily gains by steers that grazed perennial ryegrass were greater than by steers that grazed orchardgrass but …

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Pastures And Pasture Management For High Animal Production In New Zealand, R W. Brougham, G P. Cosgrove Oct 2025

Pastures And Pasture Management For High Animal Production In New Zealand, R W. Brougham, G P. Cosgrove

IGC Proceedings (1977-2023)

Limits to pasture and animal production from perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) pastures have been studied in systems experiments with fattening dairy beef bulls in the lowland Manawatu region of New Zealand. At high stocking rates the management system utilizes peak spring pasture growth and provides sufficient herbage for animals during periods of low growth in self contained, no conservation farmlets. High animal production of approximately 1000 kg of carcass meat/ha annually has been achieved. Accumulation of pasture reserves in autumn through long rotations and reductions in grazing pressure in summer through slaughter of fattened animals …

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Mosaic Grazing - Animal Selectivity In Tropical Savannas Of Northern Australia, J J. Mott Oct 2025

Mosaic Grazing - Animal Selectivity In Tropical Savannas Of Northern Australia, J J. Mott

IGC Proceedings (1977-2023)

In set stocked, heavily grazed, unburnt, native grass/sown legume pastures in the tropical savannas of northern Australia, animals were found to graze very selectively. This contrasts with the more uniform light grazing usually occurring in the extensive, lightly grazed native grasslands which are normally burnt annually. Once heavy selective grazing of an area was initiated, this grazing pressure was maintained, while ungrazed areas grew rank and unacceptable. Although three different sized paddocks were used to give different stocking rates, the area heavily grazed was the same at all stocking rates. In unfertilised paddocks, plants died within two years when selectively …

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