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Cattle And Sheep Mixed Grazing: 2. Competition, S. J. C. González-Montagna, Pedro A. Martínez-Hernández, R. D. Améndola-Massiotti

IGC Proceedings (1977-2023)

The outcome of mixed grazing depends on the degrees of complementarity and competition between animal species. Complementarity increases the utilisation of herbage resource but competition may be desirable when one grazing species has a higher priority ranking in the farming system. A species wins in the competition by harvesting a higher proportion of the available herbage than the other (Nicol, 1997). De Wit (1960) used the replacement series based on degrees of substitution of species, for the quantification of the outcome of mixtures experiments. The use of species equivalence is required in order to apply this approach to the analysis …

Cattle And Sheep Mixed Grazing: 1. Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, Pedro A. Martínez-Hernández

IGC Proceedings (1977-2023)

The effects of mixed grazing of cattle and sheep depend on stocking rate (SR) and species ratio (Nicol, 1997). Calculations of SR and species ratio require the use of species equivalence. Equivalents are often estimated in terms of intake requirements related to live weight (LW), while maintenance energy requirements are calculated on the basis of LW^0.75. Freer (1981) stated that LW^0..9 would be more appropriate for comparisons of intake requirements for maintenance of sheep and cattle. Nonetheless, Nolan & Connolly (1977) stated that the equivalent is system-specific and depends on the species being considered. The objective of …

Diversity Of Diet Composition Decreases With Conjoint Grazing Of Cattle With Sheep And Goats, A. M. Nicol, M. B. Soper, A. V. Stewart

IGC Proceedings (1977-2023)

Conjoint or mixed grazing can affect the diet selected by each species (Nicol & Collins, 1990). Diet similarity coefficients are often used to compare pairs of diets (Krebs, 1999). However this approach is awkward when a number of contrasts are required in a multifactorial comparison. Species diversity is a descriptor of a particular environment. Many models provide an estimate of species diversity, the most common of these being a log-normal distribution (Tokeshi, 1996). We tested whether this model could be applied to dietary components selected from a pasture, and thus provide a coefficient of dietary diversity for the individual diets …

Elasticity Of Ingestive Behaviour And Intake In Sheep Associated With Food Diversity On Plurispecific Swards, C. Cortes, J. C. Damasceno, G. Bechet, J. Jamot, S. Prache

IGC Proceedings (1977-2023)

Animals on heterogeneous swards generally opt for a varied diet. This may stimulate their intake, unless searching constraints limit intake rate (Champion et al., 1998). However the management of plurispecific swards presents a risk of overgrazing the preferred species and undergrazing the less-preferred species. This study aimed to test the effect of type of diversity and type of management on the elasticity of ingestive behaviour and intake in sheep.

Theoretical Considerations On A One-Parameter Approach To Compare Actual And Estimated Compositions Of Multi-Component Diets, C. Elwert, M. Rodehutscord

IGC Proceedings (1977-2023)

The composition of ingested herbage mixtures can be estimated using the alkane technique (Dove & Moore, 1995), with the accuracy of the estimate assessed by linear regression of estimated and actual proportions of the dietary components (Dove, 1992). However, although the linear regression might not differ from the line of equality, large discrepancies may occur within individual components (Hoebee et al., 1998). This paper presents an approach to compare actual and estimated diet compositions using only one parameter.

Estimating Pasture Intake By Dairy Cows, Dennis R. Cosgrove, D. P. Cooper

IGC Proceedings (1977-2023)

Proper nutrient management planning minimizes the environmental impact of manure from dairy farms. Manure output from dairy cows can be predicted from feed intake (Wilkerson et al., 1997). Weighing feed and refusals each day can determine accurately the feed intake of dairy cows in confinement. Intake determination is more difficult for dairy cows on pasture (Vasquez & Smith, 2000). As part of a larger study aimed at estimating manure production of dairy cows on pasture, this study compares 3 methods for estimating pasture yield and feed intake.

An Evaluation Of The N-Alkane Technique For Determining Diet Composition In Animals Grazing Complex Swards, M. D. Fraser, J. M. Moorby, V. J. Theobald, R. Jones

IGC Proceedings (1977-2023)

The n-alkane profiles of epicuticular waxes derived from different plant species are sufficiently distinct to allow assessment of the proportions of different herbages in two-component mixtures including perennial ryegrass/white clover, heather/hill grass and rush/perennial ryegrass (Dove & Mayes, 1996). Evidence suggests the reliability of such estimates declines as the number of different dietary components increases. However, recent studies have shown analysis of additional compounds, including long-chain fatty alcohols, may improve discrimination between different dietary components. The aim of this experiment was to quantify the accuracy of such methods for determining the diet composition of animals grazing complex swards.

Estimating Pasture Intake By Cattle Using Alkanes And A Known Amount Of Supplement, E. Charmley, J. L. Duynisveld, H. Dove

IGC Proceedings (1977-2023)

The alkane ratio method for estimating pasture intake involves calculating the fecal ratio of plant (endogenous) and exogenous alkanes. This method is effective for sheep, although the delivery mechanism for the exogenous alkanes has presented challenges in cattle (Charmley et al. 2003). Dove et al. (2003) have shown that the relative concentration of components in a mixed diet can be estimated from fecal alkane concentrations using least squares methods. Further, if the amount of one dietary component is known, then the amount of all components, and hence intake, can be determined. In this trial beeswax was added to …

Using The N-Alkane Technique To Estimate The Herbage Intake And Diet Composition Of Cattle Grazing A Miscanthus Sinensis Grassland, Y. J. Zhang, Y. Togamura, K. Otsuki

IGC Proceedings (1977-2023)

Plant wax alkanes are now widely used as marker substances (Dove & Mayes 1991) for the estimation of forage intake and diet composition of grazing herbivores. The objective of this study was to evaluate this method with cattle grazing a M. sinensis grassland in Japan.

Rich Information In The Acoustic Signals From Feeding And Grazing In Ruminants, Montague W. Demment, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca

IGC Proceedings (1977-2023)

Because of their impact on productivity and the environment, feeding behaviour, ingestion and rumination are critical to understand intake in grazing ruminants. Many systems, mainly mechanical, have been developed to measure ingestive behaviour. However, these systems have problems, including mechanical failure and the inability to distinguish between the complex jaw movements of prehension and ingestion (Laca et al., 1994). The sounds generated by these behaviours are rich in information that holds potential not only to distinguish and count behaviours, but also identify aspects of the nature of the foods ingested.

The Sound Of Chewing, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca, M. W. Demment

IGC Proceedings (1977-2023)

Acoustic biotelemetry has been proposed as a way to count ingestive bites and chews of grazing animals. Recent work has indicated the possibility that detailed analysis of 'sounds of chewing' contains information about other characteristics of the ingestive process that can be used to study grazing behaviour of free ranging animals (Laca & Wallis DeVries, 2000), or to monitor stall-fed animals in more detail.

Development Of A 2-Dimensional Video-Acoustic Tool For Monitoring Bite Placement, Wendy Griffiths, V. Alchanatis, R. Nitzan, V. Ostrovsky, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, E. D. Ungar

IGC Proceedings (1977-2023)

Studies of grazing behaviour conducted at the spatial scale of a feeding station demonstrate that intake rate declines with increasing depletion, a response attributed to an increase in bite overlap (Ginnett et al., 1999; Ungar et al., 2001). In order to understand the rules that govern bite placement, a methodology is required that can map the sequential placement of bites on the sward surface. We developed a video-acoustic tool to achieve this and report the findings of using the tool on small uniform patches of herbage.

Spatial Heterogeneity Of Seasonal Grazing Pressure Created By Herd Movement Patterns On Hilly Rangelands Using Gps And Gis, A. I. Arnon, E. D. Ungar, T. Svoray, A. Perevolotsky, M. Shachak, H. Baram, R. Yonatan, E. Ben-Moshe, S. Brenner, D. Barkai

IGC Proceedings (1977-2023)

The spatial heterogeneity of grazing pressure on extensive rangelands has management implications (Adler et al., 2001) but it has traditionally been difficult to quantify. Combination of technologies based on GPS (Global Positioning System) and GIS (Geographic Information Systems) is a quantum leap in our ability to address this issue. These tools were used to estimate the spatial heterogeneity of grazing pressure at a farm scale, and examine the relation between local landscape features and local grazing pressure.

Chew-Bites, Jaw Movement Allocation And Bite Rate In Grazing Cattle As Identified By Acoustic Monitoring, E. D. Ungar, N. Ravid, T. Zada, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, A. Genizi

IGC Proceedings (1977-2023)

Bite rate derives from the time budget of the biting and chewing processes of intake, which are both performed by jaw movements. A new type of jaw movement was revealed by acoustic monitoring in cattle - the "chew-bite" -which chews herbage already in the mouth and harvests fresh herbage with the same jaw movement (Laca et al., 1992). Chew-biting should enable the animal to reduce the total number of jaw movements performed per bite without reducing the number of chews per bite. We examined the variation among individuals in the allocation of jaw movements between the three types, and …

Wildlife Ecological Risk Assessment In The 21st Century: Promising Technologies To Assess Toxicological Effects, Barnett A. Rattner, Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mason D. King, Rafael Mateo, Carolyn B. Meyer, Jason M. O'Brien, Christopher J. Salice

United States Geological Survey: Staff Publications

Despite advances in toxicity testing and the development of new approach methodologies (NAMs) for hazard assessment, the ecological risk assessment (ERA) framework for terrestrial wildlife (i.e., air‐breathing amphibians, reptiles, birds, and mammals) has remained unchanged for decades. While survival, growth, and reproductive endpoints derived from whole-animal toxicity tests are central to hazard assessment, nonstandard measures of biological effects at multiple levels of biological organization (e.g., molecular, cellular, tissue, organ, organism, population, community, ecosystem) have the potential to enhance the relevance of prospective and retrospective wildlife ERAs. Other factors (e.g., indirect effects of contaminants on food supplies and infectious disease processes) …

Study On Modification Of Plant Gum Flushing Fluid In Coal-Bearing Strata And Its Mechanism, Xie Chengchao, Wang Sheng, Yan Peng, Chen Liyi, Li Bingle, Zhang Jie

Coal Geology & Exploration

To improve the adverse effects of the depletion of plant gum resources on the application of flushing fluid in complex strata such as coal-bearing strata, a study was conducted on the compound and crosslinking modification of guar gum. A new type of plant gum flushing fluid (GXB) was developed using xanthan gum as the compound synergist and organic boron as the crosslinking modifier, with cross-linking control agent and inorganic treatment agent as the supplementary. Meanwhile, a series of performance evaluation was carried out. The evaluation results show that GXB has excellent performance and can meet the requirements of drilling in …

Ice-Core Reveals Flavors Of Hydroclimate Extremes In The American Southwest, Laura Calabrò

USF Tampa Graduate Theses and Dissertations

A small number of caves and lava tubes worldwide host perennial ice deposits, which occur at elevations well below those of mountain glaciers and in areas outside the permafrost climatic belt, where no surface glaciation exists. These settings make any of the ice deposits in caves or lava tubes particularly susceptible to the current warming trend, leading to the imminent loss of some untapped cryospheric paleoenvironmental archives.

The present work is the result of a paleoclimate study based on ice deposits accumulated within lava tubes in El Malpais National Monument (ELMA, western New Mexico). The ice cores span from 7,000 …

Environmental Chemical Analysis Method Optimization And Application To Northwest Cuban Marine Sediment, Thea R. Bartlett

USF Tampa Graduate Theses and Dissertations

A method for gas chromatography tandem mass spectrometry (GC-MS/MS) in selected reaction monitoring (SRM) mode has been optimized to quantify 250 compounds of a variety of compound classes such as polycyclic aromatic hydrocarbons (PAHs), oxidized PAHs, organochlorinated pesticides, polychlorinated biphenyls, biomarkers (hopanes, steranes, tri-aromatic steroids, and fecal sterols), aliphatic hydrocarbons, and plastic additives. This method was validated based on available QA/QC standards using several environmental samples, both sediment and biota, and standard reference materials. This contaminant-focused method can be used as a forensic geochemistry tool to evaluate oil contamination and other contaminant histories in future research studies. When applied to …

Ecological Governance Of Aral Sea: Important Way To Deepen Scientific And Technological Cooperation With Central Asia, Miao Wu, Jianfang Qiao, Yuanming Zhang, Changyan Tian, Yaoming Li, Yun Hao, Xiaoyun Zhang, Lixian Wang, Jingjing He

Bulletin of Chinese Academy of Sciences (Chinese Version)

In September 2022, the President of the People’s Republic of China visited Uzbekistan for the first time after the epidemic. In the subsequent joint statement between China and Uzbekistan, China welcomed the adoption of the Aral Sea initiative proposed by Uzbekistan at the General Assembly of the United Nations. The two sides expressed their willingness to actively promote synergy between the Global Development Initiative and projects related to improving the ecological, economic, and social environment of the Aral Sea region under the framework of the United Nations. In this context, this paper describes the current situation of the Aral Sea …

Marine Anoxia Initiates Giant Sulfur-Bacteria Mat Proliferation And Associated Changes In Benthic Nitrogen, Sulfur, And Iron Cycling In The Santa Barbara Basin, California Borderland, David J. Yousavich, De'marcus Robinson, Xuefeng Peng, Sebastian J.E. Krause, Frank Wenzhoefer, Felix Janßen, Na Liu, Jonathan Tarn, Frank Kinnaman, David L. Valentine, Tina Treude

Faculty Publications

The Santa Barbara Basin naturally experiences transient deoxygenation due to its unique geological setting in the southern California Borderland and seasonal changes in ocean currents. Long-term measurements of the basin showed that anoxic events and subsequent nitrate exhaustion in the bottom waters have been occurring more frequently and lasting longer over the past decade. One characteristic of the Santa Barbara Basin is the seasonal development of extensive mats of benthic nitrate-reducing sulfur-oxidizing bacteria, which are found at the sediment–water interface when the basin's bottom waters reach anoxia but still provide some nitrate. To assess the mat's impact on the benthic …

Impact Of Land Use/Cover Change And Slope Gradient On Soil Organic Carbon Stock In Anjeni Watershed, Northwest Ethiopia, Bethel Geremew, Tsegaye Tadesse, Bobe Bedadi, Hero T. Gollany, Kindie Tesfaye, Abebe Aschalew

National Drought Mitigation Center: Faculty Publications

Today’s agri-food systems face the triple challenge of addressing food security, adapting to climate change, and reducing the climate footprint by reducing the emission of greenhouse gases (GHG). In agri-food systems, changes in land use and land cover (LULC) could affect soil physicochemical properties, particularly soil organic carbon (SOC) stock. However, the impact varies depending on the physical, social, and economic conditions of a given region or watershed. Given this, a study was conducted to quantify the impact of LULC and slope gradient on SOC stock and C sequestration rate in the Anjeni watershed, which is a highly populated and …

The Effect Of Harvesting Strategy Of Grass Silage On Milk Production, K. Kuoppala, M. Rinne, J. Nousiainen, P. Huhtanen

IGC Proceedings (1977-2023)

Timing of harvest in primary growth of grass is a major factor affecting D-value (digestible organic matter, g/kg DM) of silage and dry matter (DM) consumption and milk production of dairy cows (Rinne, 2000). The objective of this research was to investigate whether there is a similar pattern in regrowths of grass.

The Effect Of Harvesting Strategy Of Grass Silage On Milk Production, K. Kuoppala, M. Rinne, J. Nousiainen, P. Huhtanen

IGC Proceedings (1977-2023)

Timing of harvest in primary growth of grass is a major factor affecting D-value (digestible organic matter, g/kg DM) of silage and dry matter (DM) consumption and milk production of dairy cows (Rinne, 2000). The objective of this research was to investigate whether there is a similar pattern in regrowths of grass.

The Effects Of Offering Hay, Pit-Stored Grass Silage Or Big-Bale Silage To Pregnant Ewes On Ewe And Lamb Performance, T. F. Crosby, P. J. Quinn, J. J. Callan, T. Mcgrane

IGC Proceedings (1977-2023)

Hay and pit silage have been used extensively for feeding sheep over the winter period, but in recent years, especially on smaller farms, big-bale silage has become increasingly popular. However, there is limited comparative information on the use of big-bale silage for sheep, especially in relation to the effects of chopping and growth stage at harvest. This study compared the performance of ewes offered hay, pit silage, or big-bale grass silage made from either chopped or unchopped grass and cut from the same field at the same time.

The Effects Of Offering Grass Or Maize Silages To In-Lamb Ewes On Body Weight And Condition Changes, Colostrum Yield And Quality, T. F. Crosby, P. J. Quinn, J. J. Callan, P. Reilly, B. Flynn, D. Cunningham, T. Massey

IGC Proceedings (1977-2023)

Hay and more recently grass silage (GS) have been the traditional feeds for sheep in Ireland over the winter period. Alternatives such as maize silage (MS) are becoming increasingly important as winter forage sources especially for cattle. This study sought to evaluate grass silage and maize silage when offered to pregnant ewes.

Round-Bale Silage Preparation Of Rice Straw, Yimin Cai, C. Xu, N. Yoshida, M. Ogawa

IGC Proceedings (1977-2023)

Rice straw is an important feed resource for ruminants. In Japan, rice straw cannot be fully dried due to the usually humid autumn season, which leads to about 70% of the production being ploughed back or incinerated. Therefore, the development of techniques to enhance the long-term preservation and quality of rice straw is of great importance. In this work, a new lactic acid bacterium was used as a silage inoculant, and its effect on round-bale silage preparation from fresh rice straw was examined.

Factors Affecting Bag Silo Densities And Losses, R. E. Muck, B. J. Holmes

IGC Proceedings (1977-2023)

Bag silos (polyethylene tubes, 30 to 90 m length, 2.4 to 3.7 m diameter, 0.22 mm thick) are used on approximately one-third of the dairy farms in the U.S.A. for making silage, and the level of adoption is increasing rapidly. Unfortunately, almost no research data have been published on these types of silos. Our objective was to measure densities and losses in bag silos at three farms, looking for causes of variation in both.

Moisture Control, Inoculant And Particle Size In Tropical Grass Silages, S. F. Paziani, L. G. Nussio, D. R. S. Loures, L. J. Mari, José Leonardo Ribeiro, P. Schmidt, M. Zopollatto, M. C. Junqueira, A. F. Pedroso

IGC Proceedings (1977-2023)

Decreased fermentation and spoilage losses with improved aerobic stability during feed out can be accomplished by several strategies, such as wilting, addition of microbial additives and moisture absorbents. Particle size reduction may increase bulk density and improve the fermentation. The objective of this trial was to evaluate the effects of particle size, moisture content and a microbial additive on chemical-physical parameters and losses in silages made from Tanzania grass.

Effect Of A New Microbial Strain As An Inoculant On The Quality Of Maize Silage, J. G. Kim, J. S. Ham, E. S. Chung, S. Seo, J. K. Lee

IGC Proceedings (1977-2023)

Lactic acid bacteria play a key role in making silage from forage, and lactic acid bacteria selected from good silage could be expected to be suitable inocula for making good silage. Thus, the purpose of this study was to examine the such novel lactic acid bacteria for making high quality maize silage.

The Potential Of Different Forage Combinations For Green-Chop Silage, Trevor L. Knight, Tom J. Fraser, T. A. White, M. G. Hyslop

IGC Proceedings (1977-2023)

On the Canterbury Plains of New Zealand (NZ) there is an opportunity on cropping farms, between summer harvest and autumn/winter sowing, to grow forage crops to make high quality silage. Recently, cereal cultivars have been specifically bred for forage production and suitability for whole-crop silage (de Ruiter et al. 2002), and also high legume (e.g. sulla) content forage mixes have resulted in high quality silages with high lactic acid and soluble carbohydrate content (Niezen et al. 1998). This trial aimed to determine the yield potential of various cereal/legume forage mixtures summer sown and harvested for silage in autumn.