Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 12601 - 12630 of 302419

Full-Text Articles in Physical Sciences and Mathematics

The Timing Of Daily Grazing On Annual Ryegrass Or Sulla Forage: The Effects On Milk Yield And Composition Of Comisana Ewes, D. Giambalvo, L. Stringi, C. Scarpello, P. Iudicello, A. Bonanno, A. Di Grigoli Jun 2023

The Timing Of Daily Grazing On Annual Ryegrass Or Sulla Forage: The Effects On Milk Yield And Composition Of Comisana Ewes, D. Giambalvo, L. Stringi, C. Scarpello, P. Iudicello, A. Bonanno, A. Di Grigoli

IGC Proceedings (1993-2023)

The timing and duration of grazing greatly affect the response of animals. Night grazing, in addition to grazing during the day, seems to be one of the most important practices for improving animal performance (Bayer et al., 1987). Many authors have already underlined the major benefits of night grazing, such as improved body condition, reduced heat stress, increased forage intake and milk production. However, labour constraints, insecurity, damage to crops by animals are considered as the main reasons for not practising day and night grazing. The aim of this research was to improve knowledge about the effects of daily …

Go to article

Herbage Production Of Tanzania Grass (Panicum Maximum Cv. Tanzania) Submitted To Combinations Of Frequencies And Intensities Of Grazing By Cattle, Domicio Nascimento Jr., Rodrigo A. Barbosa, Valéria P. B. Euclides, S. C. Da Silva, R. A. Torres Jun 2023

Herbage Production Of Tanzania Grass (Panicum Maximum Cv. Tanzania) Submitted To Combinations Of Frequencies And Intensities Of Grazing By Cattle, Domicio Nascimento Jr., Rodrigo A. Barbosa, Valéria P. B. Euclides, S. C. Da Silva, R. A. Torres

IGC Proceedings (1993-2023)

Animal production from pastures is a complex process comprising three main stages: herbage growth, consumption by grazing animals and conversion into animal products (Hodgson, 1990). Utilisation is the stage where the grazier finds greater flexibility for management, probably because most processes related to harvest of the produced herbage by the grazing animals are very responsive to manipulation and control of defoliation practices. The objective of this study was to evaluate herbage production of a Panicum maximum cv. Tanzania pasture submitted to combinations of frequencies and intensities of grazing.

Go to article

The Effects Of Proximity To Watering Points On Vegetation Parameters In Winter Rangelands Of Chahe-Nou, Damghan, Iran, R. Khalifeh-Zadeh, Mansour Mesdaghi Jun 2023

The Effects Of Proximity To Watering Points On Vegetation Parameters In Winter Rangelands Of Chahe-Nou, Damghan, Iran, R. Khalifeh-Zadeh, Mansour Mesdaghi

IGC Proceedings (1993-2023)

The Chahe-Nou with 115 mm rainfall and high temperatures (30 °C) is located 95 km south of Damghan. It is grazed intensively by nomadic and sedentary sheep and goats during winter. Proximity to watering points affects the rangelands vegetation. With increasing distance from the watering points more palatable species increase, whilst grazing decreases. The areas nearest the watering points contain more unpalatable undesirable invasive species (Department of Natural Resources, 1999). The objective of this research was to evaluate the effects of proximity to watering point on vegetation parameters at two watering points.

Go to article

Grazing Behaviour Of Lambs In Different Production Systems, C. H. E. C. Poli, Alda L. G. Monteiro, C. S. Gomes, G. J. Bosquetto, J. R. Dittrich, Susana Gilaverte, H. V. L. Piazetta Jun 2023

Grazing Behaviour Of Lambs In Different Production Systems, C. H. E. C. Poli, Alda L. G. Monteiro, C. S. Gomes, G. J. Bosquetto, J. R. Dittrich, Susana Gilaverte, H. V. L. Piazetta

IGC Proceedings (1993-2023)

Ingestive behaviour is an important component of a grazing system (Fryxell et al., 2001). The understanding of lamb behaviour patterns in different production systems is crucial to management and to assess the impact of the production system on the use of resources by animals. The objective of this study was to determine the grazing behaviour of lambs in different production systems.

Go to article

Herbage Intake And Animal Performance Of Cattle Grazing Brachiaria Brizantha Cv. Marandu Under Continuous Stocking, S. C. Da Silva, P. Sarmento, L. K. Molan, F. M. E. Andrade, André F. Sbrissia, A. V. Lupinacci, A. C. Gonçalves, D. E. Oliveira Jun 2023

Herbage Intake And Animal Performance Of Cattle Grazing Brachiaria Brizantha Cv. Marandu Under Continuous Stocking, S. C. Da Silva, P. Sarmento, L. K. Molan, F. M. E. Andrade, André F. Sbrissia, A. V. Lupinacci, A. C. Gonçalves, D. E. Oliveira

IGC Proceedings (1993-2023)

Grazing management affects sward structure, which in turn influences plant and animal responses. With the objective of understanding causal relationship between sward structure and animal responses, the present experiment evaluated the daily herbage intake and live weight gain of growing cattle on Brachiaria brizantha cv. Marandu pasture during summer (Dec. 2001 to Mar. 2002).

Go to article

Evaluating The Impacts Of The Transition From Open-Pit To Underground Mining On Sustainable Development Indexes, Naser Badakhshan, Kourosh Shahriar, Sajjad Afraei, Ezzeddin Bakhtavar Jun 2023

Evaluating The Impacts Of The Transition From Open-Pit To Underground Mining On Sustainable Development Indexes, Naser Badakhshan, Kourosh Shahriar, Sajjad Afraei, Ezzeddin Bakhtavar

Journal of Sustainable Mining

Sustainable development is about creating a balance between development and environment, and it consists of three essential principles: environment, society, and economy. Today, one of the most important challenges in deep open pit mines is the transition from open pit to underground, which has positive and negative impacts on sustainable development indexes. In order to reduce these adverse impacts, the impact of various parts of the transition operation on these indexes should be evaluated and corrective and preventive measures should be implemented. In this study, using a hybrid semi-quantitative approach, the effects of the transition in the Songun copper mine …

Go to article

Applications Of Financial Mathematics: An Analysis Of Consumer Financial Decision Making, Alyssa Betterton Jun 2023

Applications Of Financial Mathematics: An Analysis Of Consumer Financial Decision Making, Alyssa Betterton

Honors Theses

Students always ask, “How can this be applied to the real world?” Mortgages, car loans, and credit card bills are things that almost everyone will have to make decisions about at some point in their lives. This research discusses the many different financial choices that consumers have to make. Consumers can use this information to understand how interest rates, the length of the loan, and the initial amount being borrowed affects the amount that is paid back to the companies. The intent of this thesis is to present the mathematical theory of interest. A web-based application has been built based …

Go to article

Effect Of Red And White Clover Added To A Rye Grass-Based Diet On Intake, Fibre Digestion And Methane Release Of Dairy Cows, Anette H. Van Dorland, Michael Kreuzer, M. Leuenberger, H. R. Wettstein Jun 2023

Effect Of Red And White Clover Added To A Rye Grass-Based Diet On Intake, Fibre Digestion And Methane Release Of Dairy Cows, Anette H. Van Dorland, Michael Kreuzer, M. Leuenberger, H. R. Wettstein

IGC Proceedings (1993-2023)

Forage legumes like white and red clover are widely grown in association with grass, with the intention to improve the quality of grass-based diets. However little is known about the effect of either white or red clover added to a grass-based diet on methane release, and existing studies are not conclusive. The objective of this study, applying the respiratory chamber technique, was to determine the effect of red and white clover added to a rye grass-based diet on intake, fibre digestion and methane release of dairy cows.

Go to article

Reproductive Allocation In Brassica Kaber, Caroline Brophy, John Connolly, P. M. Wayne, D. J. Gibson Jun 2023

Reproductive Allocation In Brassica Kaber, Caroline Brophy, John Connolly, P. M. Wayne, D. J. Gibson

IGC Proceedings (1993-2023)

Understanding the reproductive biology of weeds is essential to understanding their role in seminatural plant communities. The annual forb Brassica kaber is an important agricultural weed in the mid-western regions of the U.S.A. Linear regression is often used to establish the relationship between the reproductive mass (R) of a plant (as measured by number of flowers, seeds or mass of reproductive organs) and its dry mass (W)(Sletvold, 2002). Some plants do not have any reproductive output (R=0). These zero values cause a problem forlinear regression. Schmid et al. (1994) suggested using truncated regression as a solution. In this presentation …

Go to article

Inheritance Of Yield, Morphological And Quality Characteristics In Cocksfoot (Dactylis Glomerata), A. A. Jafari, H. M. Arefi, H. Nasri Jun 2023

Inheritance Of Yield, Morphological And Quality Characteristics In Cocksfoot (Dactylis Glomerata), A. A. Jafari, H. M. Arefi, H. Nasri

IGC Proceedings (1993-2023)

This study estimated genetic variation in cocksfoot (Dactylis glomerata) for yield, tiller number, heading date, dry matter digestibility (DMD), water soluble carbohydrate (WSC) and crude protein (CP).

Go to article

Proanthocyanidins From Hedysarum, Lotus And Onobrychis Spp. Growing In Sardinia And Sicily And Their Antioxidant Activity, A. Tava, M. G. De Benedetto, D. Tedesco, G. Di Miceli, G. Piluzza Jun 2023

Proanthocyanidins From Hedysarum, Lotus And Onobrychis Spp. Growing In Sardinia And Sicily And Their Antioxidant Activity, A. Tava, M. G. De Benedetto, D. Tedesco, G. Di Miceli, G. Piluzza

IGC Proceedings (1993-2023)

Proanthocyanidins (PA), or condensed tannins, are a class of natural polyphenolic compounds, occurring in numerous plant species, including a number of economically significant forage legumes. These compounds are polymers of flavan-3-ols, and typically contain from 2 to 20 units. Their biological significance is still being debated and, in recent years, a great deal of attention has been focused on their role in ruminant nutrition. Evidence has indicated that PA, in a moderate concentration (0.5-5% DM), may have considerable importance in protecting dietary proteins against microbial degradation in the rumen, and in preventing bloat. The antioxidant activity (AA) is also an …

Go to article

Carbon Sequestration In Irrigated Pastures, Glenn E. Shewmaker, J. A. Entry, R. E. Sojka Jun 2023

Carbon Sequestration In Irrigated Pastures, Glenn E. Shewmaker, J. A. Entry, R. E. Sojka

IGC Proceedings (1993-2023)

Carbon sequestration potential for irrigated grazing lands is significant. We measured organic and inorganic C stored in southern Idaho soils having long-term land use histories that supported native sagebrush vegetation (NSB), irrigated pasture systems (IP), irrigated conservation tillage sites (ICT), and irrigated moldboard plowing systems (IMP). This study estimates the amount of possible organic, inorganic and total C sequestration if irrigated pasture land was expanded by 10%.

Go to article

The Carbon Balance Of Long Term And Newly Established Temperate Grasslands, J. Clifton-Brown, G. Lanigan, R. B. Taylor, J. I. Burke, M. B. Jones Jun 2023

The Carbon Balance Of Long Term And Newly Established Temperate Grasslands, J. Clifton-Brown, G. Lanigan, R. B. Taylor, J. I. Burke, M. B. Jones

IGC Proceedings (1993-2023)

Carbon (C) sequestration is the process of removing CO2 from the atmosphere and storing it in C pools of varying lifetime. Storage can be in the form of above-ground biomass, below-ground biomass or recalcitrant organic and inorganic C in the soil. While the processes of C sequestration are ultimately regulated at the molecular level, management practices and climate can greatly affect the way in which terrestrial ecosystems sequester C (Soussana et al., 2004). Because temperate grasslands account for a significant portion of the agricultural and semi-natural land-cover in N-W Europe any increase in the potential of temperate grasslands …

Go to article

Carbon Sequestration In Pasture And Silvo-Pastoral Systems In Ecosystems Of The Latin American Tropics, M. C. Amézquita, M. Ibrahim Jun 2023

Carbon Sequestration In Pasture And Silvo-Pastoral Systems In Ecosystems Of The Latin American Tropics, M. C. Amézquita, M. Ibrahim

IGC Proceedings (1993-2023)

Conversion of forests to pastures has been the most important land use change in tropical America (TA) in the last fifty years. After deforestation and pasture establishment many areas have been abandoned due to productivity declines arising through mismanagement. Over 60% of the TA's pasture area is degraded. Recent interest in carbon sequestration and environmental considerations might suggest partial reforestation of current pastoral areas but this has implications for the socio-economic welfare of farmers and food availability. However, combining agricultural production with environmental objectives (particularly carbon sequestration) could provide a sustainable alternative. Here we present 3-years of research on the …

Go to article

The Use Of Long-Term Modelling In Analysing N2O Abatement Strategies In Dairy Pastures, Richard J. Eckard, I. R. Johnson, D. F. Chapman Jun 2023

The Use Of Long-Term Modelling In Analysing N2O Abatement Strategies In Dairy Pastures, Richard J. Eckard, I. R. Johnson, D. F. Chapman

IGC Proceedings (1993-2023)

Concerns about the environmental impact of nitrogen (N) losses in Australia, in particular, nitrous oxide emissions are related to the rapid increase in N application on dairy pastures. Computer modelling is the most suitable method available to assess the potential of best management practices (BMP) to reduce field losses, as direct field measurements are frequently limited by the short term nature of many field trials.

Go to article

Time Budget On Major Activities Of Livestock Grazing Heterogeneous Natural Range And Crop Fields In Semi-Arid Nigeria, B. S. Malami, P. H. Y. Hiernaux, H. M. Tukur, J. Steinbach Jun 2023

Time Budget On Major Activities Of Livestock Grazing Heterogeneous Natural Range And Crop Fields In Semi-Arid Nigeria, B. S. Malami, P. H. Y. Hiernaux, H. M. Tukur, J. Steinbach

IGC Proceedings (1993-2023)

Semi-arid rangelands of West Africa provide herbs, trees and shrubs, which together with crop residues form the main sources of feed for the livestock population. Feed supply in this region is characterised by a progressive decline in quantity and quality with advancing dry season. It was reported that walking ability as well as watering frequencies affect the productivity of grazing livestock (Dicko and Sangare, 1984). This study tests the hypothesis that advancing season increases both time spent walking as well as feeding, with a switch from grazing to browsing.

Go to article

Effect Of Time Spent On Pasture On Grazing Behaviour In Latxa Dairy Sheep, A. Garcia-Rodriguez, N. Mandaluniz, L. M. Oregui Jun 2023

Effect Of Time Spent On Pasture On Grazing Behaviour In Latxa Dairy Sheep, A. Garcia-Rodriguez, N. Mandaluniz, L. M. Oregui

IGC Proceedings (1993-2023)

In the Basque country the dairy ewe production system is based on a high pasture utilisation by means of partial time grazing where ewes spend a limited number of hours outdoors (Oregui et al., 1997). This production system, which is also typical of other Mediterranean areas, is different from that in northern Europe where continuous grazing is the usual management. There is a lack of knowledge concerning grazing behaviour under these conditions. This research investigated the effect of time spent on pasture on grazing behaviour.

Go to article

Diet Selection In A Pasture Of Panicum Maximum Cv. Mombaça With Different Sward Heights, Teresa C. M. Genro, Ê. R. Prates, F. F. Cardoso, L. R. L. San'thiago Jun 2023

Diet Selection In A Pasture Of Panicum Maximum Cv. Mombaça With Different Sward Heights, Teresa C. M. Genro, Ê. R. Prates, F. F. Cardoso, L. R. L. San'thiago

IGC Proceedings (1993-2023)

The n-alkane method allows to measure dry matter (DM) intake and to determine the proportion of grass and legume ingested by ruminants grazing mixed pastures. Dove & Mayes (1996) pointed out that using this method, beyond estimating intake of individual plant species, it may also be possible to determine intake of anatomical components of the plant. The aim of this work was to use the non-negative least squares procedure to estimate diet selection based on plant alkanes and animal faeces.

Go to article

A Simple Vegetation Criterion (Ndf Content) May Account For Diet Choices Of Cattle Between Forages Varying In Maturity Stage And Physical Accessibility, Cécile Ginane, R. Baumont Jun 2023

A Simple Vegetation Criterion (Ndf Content) May Account For Diet Choices Of Cattle Between Forages Varying In Maturity Stage And Physical Accessibility, Cécile Ginane, R. Baumont

IGC Proceedings (1993-2023)

The management of extensively grazed pastures requires an understanding and prediction of the diet choices of herbivores grazing on vegetation that is qualitatively (maturity stage) and quantitatively (biomass, sward height) heterogeneous. The Optimal Foraging Theory (OFT, Stephens & Krebs, 1986), bases its predictions on the relative energy intake rate (EIR) of forages. However, as EIRs are difficult to assess at pasture and are subject to wide intra- and inter-individual variations, another vegetation criterion was sought (accessibility, quality), by-passing the animal's influence, to predict cattle diet choices quantitatively.

Go to article

Influence Of Giving A Choice Of Grazing Or Maize Silage Offered In The Field Simultaneously On Diet Selection Of Lactating Dairy Cows, O. Hernández‐Mendo, J. D. Leaver Jun 2023

Influence Of Giving A Choice Of Grazing Or Maize Silage Offered In The Field Simultaneously On Diet Selection Of Lactating Dairy Cows, O. Hernández‐Mendo, J. D. Leaver

IGC Proceedings (1993-2023)

Changing the times of access to grazing and to maize silage (MS) offered indoors affects the relative intake of each feed, but has little effect on dairy cow performance (Hernandez-Mendo & Leaver, 2000). Offering the MS in the grazing paddock as an instantaneous alternative to grazing should give an insight into the factors influencing feed intake, and may provide a means of alleviating the high rate of decline in milk yield of grazing dairy cows. The objective of this study was to examine the response in diet preferences and performance of lactating dairy cows when grazing a perennial ryegrass sward …

Go to article

A Sward Based Method To Estimate Herbage Selection Of Grazing Dairy Cows, F. Taube, M. Wachendorf, J. Baade Jun 2023

A Sward Based Method To Estimate Herbage Selection Of Grazing Dairy Cows, F. Taube, M. Wachendorf, J. Baade

IGC Proceedings (1993-2023)

Diet selection of grazing animals is influenced by sward composition and vertical sward structure. Grazing studies were established in northern Germany (Kiel, Schleswig - Holstein state) to determine if selective grazing behaviour in a mixed sward can be measured by a sward based method. The hypothesis that active selection of different functional groups of forages can be documented by using the selection index (Figure 1, Hodgson, 1990) and regressive approaches vs time was tested.

Go to article

Biomass Vertical Distribution In A Grazed Grassland Under Monoespecific And Mixed Grazing, C. Saroff, S. González, A. Ohanian, H. Pagliaricci, Y. R. Chiaramello Jun 2023

Biomass Vertical Distribution In A Grazed Grassland Under Monoespecific And Mixed Grazing, C. Saroff, S. González, A. Ohanian, H. Pagliaricci, Y. R. Chiaramello

IGC Proceedings (1993-2023)

Mixed grazing is defined as the use of the same forage resource for more than one herbivore species. It has been shown that different herbivore species have specific grazing modalities (Black and Kenney, 1984), which may differentially modify the structure of the pasture. The aim of this study was to evaluate the biomass vertical distribution in a sward with mixed grazing.

Go to article

Cattle And Sheep Mixed Grazing: 2. Competition, S. J. C. González-Montagna, Pedro A. Martínez-Hernández, R. D. Améndola-Massiotti Jun 2023

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

IGC Proceedings (1993-2023)

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 …

Go to article

Cattle And Sheep Mixed Grazing: 1. Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, Pedro A. Martínez-Hernández Jun 2023

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

IGC Proceedings (1993-2023)

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 LW0.75. Freer (1981) stated that LW0..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 …

Go to article

Diversity Of Diet Composition Decreases With Conjoint Grazing Of Cattle With Sheep And Goats, A. M. Nicol, M. B. Soper, A. V. Stewart Jun 2023

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 (1993-2023)

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 …

Go to article

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 Jun 2023

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 (1993-2023)

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.

Go to article

Theoretical Considerations On A One-Parameter Approach To Compare Actual And Estimated Compositions Of Multi-Component Diets, C. Elwert, M. Rodehutscord Jun 2023

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

IGC Proceedings (1993-2023)

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.

Go to article

Estimating Pasture Intake By Dairy Cows, Dennis R. Cosgrove, D. P. Cooper Jun 2023

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

IGC Proceedings (1993-2023)

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.

Go to article

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 Jun 2023

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 (1993-2023)

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.

Go to article

Estimating Pasture Intake By Cattle Using Alkanes And A Known Amount Of Supplement, E. Charmley, J. L. Duynisveld, H. Dove Jun 2023

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

IGC Proceedings (1993-2023)

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 …

Go to article

First Prev Next Last