Application of n-alkanes as diet composition markers in grazing/browsing goats and sheep: effect of using different faecal recovery corrections and plant species grouping approaches

2007 ◽  
Vol 58 (11) ◽  
pp. 1013 ◽  
Author(s):  
M. Oliván ◽  
L. M. M. Ferreira ◽  
U. García ◽  
R. Celaya ◽  
K. Osoro
Keyword(s):  
Plant Species ◽  
Diet Composition ◽  
Animal Species ◽  
Calluna Vulgaris ◽  
Individual Plant ◽  
Botanical Composition ◽  
Agrostis Capillaris ◽  
Dietary Components ◽  
Equal Weighting ◽  
Species Grouping

The present study aimed to test the effect of applying different sets of n-alkane faecal recoveries and different plant species grouping approaches on the estimates of the diet selected by goats and sheep when grazing/browsing complex vegetation communities composed of mosaics of heather-gorse vegetation interspersed with patches of perennial ryegrass. The use of different sets of n-alkane faecal recoveries significantly affected the estimated proportions of most vegetation components in both animal species. The diet estimates were also significantly affected by the calculation approach: A1 (using all individual plant species); A2 (grouping plant species with similar n-alkane profile, with equal weighting within the group); and A3 (grouping plant species with similar n-alkane profile, with different weighting according to the botanical composition of the plot). There was a significant interaction between calculation approach (A) and faecal recovery sets (FR) on the resulting estimates of the Ericaceae species in the diet of goats and of all diet components in sheep. When using A1 approach, the estimated proportion of Agrostis capillaris in the diets was high and seemed to be overestimated, compared with its low availability (1.1% of total cover) in the field. However, the application of calculation approaches A2 and A3 gave lower dietary proportions of component D2 (Agrostis capillaris and Ulex gallii) and higher proportions of components D1 (Lolium perenne and Pseudarrhenatherum longifolium), D3 (Erica umbellata, Erica cinerea, Erica australis, Calluna vulgaris) and Erica arborea. These results indicate that the application of the n-alkane technique for estimation of the diet composition in field with complex vegetation conditions is sensitive to the use of faecal recovery corrections and to the grouping of possible dietary components.

The potential of urinary metabolites of plant compounds as indicators of botanical composition of the diet of goats

2001 ◽  
Vol 2001 ◽  
pp. 146-146
Author(s):  
B. L. Keir ◽  
R. W. Mayes ◽  
E. R. Ørskov
Keyword(s):  
Plant Species ◽  
Diet Composition ◽  
Urinary Metabolites ◽  
Individual Plant ◽  
Botanical Composition ◽  
Lack Of Information ◽  
Free Ranging ◽  
The Impact ◽  
Plant Compounds ◽  
Heterogeneous Vegetation

Knowledge of the nutrition of free-ranging herbivores and the impact on their environment is often limited by lack of information concerning the botanical composition of their diets. For herbivores grazing heterogeneous vegetation environments, current methods for estimating the botanical composition of their diets are limited in their scope and accuracy. The purpose of this study was to establish whether urinary metabolites, occurring as a result of ingestion of different individual plant species, have the potential to be used as markers to estimate diet composition.

The use of alkanes as markers for estimating diet composition in sheep and goats

2006 ◽  
Vol 34 ◽  
pp. 15-20
Author(s):  
L.M.M. Ferreira ◽  
M. Oliván ◽  
M.A.M. Rodrigues ◽  
A. Dias-da-Silva ◽  
K. Osoro
Keyword(s):  
Lolium Perenne ◽  
Diet Composition ◽  
Animal Species ◽  
Live Weight ◽  
Dietary Treatment ◽  
Dietary Components ◽  
Dietary Treatments ◽  
Long Chain ◽  
Selection Of ◽  
Plant Components

SummaryAn experiment was carried out to evaluate the use of alkanes for estimating diet composition of goats and sheep offered three different dietary treatments. Twelve animals as two groups of 4 crossbred goats (G1, 24 kg live weight; G2, 22 kg) and 4 crossbred sheep (S, 26 kg live weight), were housed in metabolism pens. Animals were offered daily a total of 1 kg DM/100 kg live weight. G1 received 70% ryegrass (Lolium perenne) and 30% gorse (Ulex gallii), G2 received 70% ryegrass and 30% heather (Erica sp.) and S group ate 100% ryegrass. Diet composition was estimated from the alkane concentrations (using all alkanes from C23 to C36 or only odd-chain alkanes C27, C29, C31 and C33) in diet and faeces (with or without correction for incomplete faecal recoveries) using least-squares procedures.Dietary treatment and animal species significantly affected alkane faecal recoveries, except for C24 and C36. When applying the faecal recovery corrections, there were no significant differences between measured proportions of dietary components and those estimated using all alkanes or odd-chain alkanes. In contrast, the proportions calculated without faecal recovery correction differed significantly (P<0.05) from the actual proportions and over-estimated the amount in the diet of those plant components with higher concentrations of long-chain alkanes (Erica sp. and Lolium perenne). The results indicate that alkanes are useful markers to estimate diet composition, however, it was observed that animal species and diet composition influenced the faecal recovery of alkanes. This suggests that the use of the alkane methodology for estimating the diet selection of grazing animals should be preceded by a calculation of the actual alkane faecal recoveries for each experimental condition.

The use of plant wax alkanes as marker substances in studies of the nutrition of herbivores: a review

1991 ◽  
Vol 42 (6) ◽  
pp. 913 ◽  
Author(s):  
H Dove ◽  
RW Mayes
Keyword(s):  
Plant Species ◽  
Chemical Constituents ◽  
Individual Plant ◽  
Botanical Composition ◽  
Plant Parts ◽  
Herbage Intake ◽  
Marker Substances ◽  
Pulse Dose ◽  
Sampling Procedures ◽  
Plant Wax

This review discusses the potential use of plant wax components, especially n-alkanes, as markers for estimating herbage intake, estimating the botanical composition of consumed herbage and studying digesta kinetics. Previous approaches to making these measurements are discussed briefly. Attention is drawn to the fact that current methods for estimating intake do not adequately allow for differences between individual animals. It is also suggested that the markers currently used to estimate botanical composition or study digesta kinetics are inadequate. The nature of the chemical constituents of plant waxes is briefly discussed and the concept of using alkanes to estimate intake is introduced. Particular emphasis is given to the fact that although the recovery of alkanes in faeces is not complete, intake can still be estimated using a pair of alkanes (one natural, one dosed) provided these have similar faecal recoveries. The accuracy of estimation of intake is discussed in terms of: obtaining a representative sample of herbage; alkane dosing and faecal sampling procedures; validity of the assumption of similar recoveries for the natural and dosed alkanes; sample preparation and analysis. Published comparisons of estimated and actual intakes are presented, with the conclusion that satisfactory results are obtained if intake is estimated using natural C33 alkane and dosed C32 alkane. The use of the different patterns of alkanes in herbage species, as a means of estimating botanical composition, is then discussed. Results are presented showing this can be done successfully with herbage mixtures or oesophageal extrusa. Procedures are then described for making the corrections for incomplete faecal alkane recovery, necessary to estimate the botanical composition of the herbage consumed by the free-grazing animal. This allows the quantification of the intake of individual plant species by individual animals, and it is suggested that this can be achieved without the need for oesophageally-fistulated (OF) animals. Differences in alkane levels between plant parts within a species are then discussed. It is suggested that these can lead to error in the estimation of intake, if OF animals should consume plant parts different from those consumed by the test animals. However, it is also suggested that differences in alkane levels between plant parts can be used to quantify the intake of these parts, in a manner analogous to the estimation of the intake of individual plant species. The usefulness of alkanes in studies of digesta kinetics is then discussed, principally in relation to the natural alkanes, which remain intimately associated with plant particles in the gut. It is suggested that natural alkanes could prove excellent markers for studies of particle breakdown and digesta flow. The preparation of natural 14C-labelled alkane, for use as a pulse dose in mean retention time studies, is also discussed.

The possible use of n-alkanes, long-chain fatty alcohols and long-chain fatty acids as markers in studies of the botanical composition of the diet of free-ranging herbivores

2005 ◽  
Vol 143 (1) ◽  
pp. 85-95 ◽  
Author(s):  
H. A. M. ALI ◽  
R. W. MAYES ◽  
B. L. HECTOR ◽  
A. K. VERMA ◽  
E. R. ØRSKOV
Keyword(s):  
Fatty Acids ◽  
Plant Species ◽  
Diet Composition ◽  
Fatty Alcohols ◽  
Estimation Methods ◽  
Individual Plant ◽  
Long Chain Fatty Acids ◽  
Free Ranging ◽  
Long Chain ◽  
Chain Fatty Acids

Few methods exist for estimating quantitatively the diet composition of free-ranging herbivores. The current study examined whether long-chain fatty alcohols (alcohols) or long-chain fatty acids (acids) could be used along with n-alkanes to allow reliable diet composition estimates to be made in herbivores consuming complex diets. Twelve Scottish Blackface wether sheep housed in metabolism crates were fed four different mixtures of three plant species (three animals per mixture) for a seven-period experiment. Concentrations of cuticular wax n-alkanes, alcohols and acids were estimated in samples of individual plant species, and the faeces from animals that consumed mixtures of these species. These concentrations were then used to calculate the dietary proportions of each species by a least-squares optimization procedure. To explore the differences between the estimation methods (individual markers and their combinations), the mean squares of errors (EMS) between the actual and predicted proportions of plant species were calculated.In three out of the four mixtures, alcohols had the lowest discrepancies (lowest EMS values), followed by n-alkanes and then acids. Acids yielded the lowest discrepancy in one mixture and the highest in the others.It is concluded that, for this particular set of mixtures, alcohols had great potential to estimate composition of complex diets. However, the estimation using acids was less good and n-alkanes were of intermediate potential. Estimation from the combination of the three marker classes was always better than using the poorest individual marker.

Effects of the vertical and horizontal availability of food resources: the diet selection of sheep grazing on natural grassland

2014 ◽  
Vol 153 (2) ◽  
pp. 322-334 ◽  
Author(s):  
W. Q. CHEN ◽  
X. Y. WANG ◽  
Y. J. ZHANG ◽  
D. HUANG
Keyword(s):  
Plant Species ◽  
Diet Composition ◽  
Influencing Factor ◽  
Diet Selection ◽  
Leymus Chinensis ◽  
Individual Plant ◽  
Stocking Rate ◽  
Grazing Impacts ◽  
Rate Plot ◽  
June July

SUMMARYThe relationship between sheep diet selection and the vertical/horizontal availability of plant species on complex natural Leymus chinensis grassland was investigated. Two plots (low and high stocking rate plots) with different vegetation availabilities, created by adjusting sheep numbers, were studied for 3 months (June, July and August). In each month, the sheep's diet composition was estimated using n-alkanes in combination with long-chain alcohols and/or fatty acid markers. Vertical (sward surface height) and horizontal food availability (proportion cover of individual plant species) were determined simultaneously. The results revealed that sheep diet composition varied greatly according to seasonal variations in vegetation availability, and that sheep diet selection was related to the vertical and horizontal availability of plant species on both plots. Horizontal availability, which turned out to be the main influencing factor, was strongly and positively correlated with sheep diet composition in each month on both plots. On the low stocking rate plot, vertical availability affected sheep consumption in June, July and August. In contrast, a significant correlation between diet composition and vertical availability was only observed in July on the high stocking rate plot. These results suggest that the relative importance of vertical and horizontal availability differed between plots depending on vegetation availability. Horizontal availability played a more important role than vertical availability when sheep grazed freely on natural L. chinensis grassland. Finally, the changing selectivity index for each plant species in each grazing period on both plots indicated different grazing impacts on vegetation communities when vegetation availability differed.

Estimating diet composition for mountain hares in newly established native woodland: development and application of plant-wax faecal markers

2003 ◽  
Vol 81 (6) ◽  
pp. 1047-1056 ◽  
Author(s):  
Shaila J Rao ◽  
Glenn R Iason ◽  
Ian AR Hulbert ◽  
Robert W Mayes ◽  
Paul A Racey
Keyword(s):  
Pinus Sylvestris ◽  
Diet Composition ◽  
Calluna Vulgaris ◽  
Mountain Hare ◽  
Native Woodland ◽  
Form Part ◽  
Lactating Females ◽  
Browse Species ◽  
Dietary Components ◽  
Plant Wax

Knowledge of the feeding ecology of mammalian herbivores is fundamental in predicting their responses to habitat change. Where native woodlands are newly established in open moorland, the extent to which trees form part of the diet of mountain hares (Lepus timidus) is unknown. This information is necessary for predicting the potential effects of mountain hare browsing on woodland establishment. The n-alkanes and a long-chain fatty alcohols found in the cuticular wax of diet plants and faeces (N = 240) were used as markers to estimate the composition of the diet of mountain hares in an area of moorland with newly established Pinus sylvestris and Betula pubescens woodland. During winter, the diet of mountain hares was dominated by Calluna vulgaris, but there was a seasonal shift to a diet dominated by grasses, sedges, and rushes in summer. Pinus sylvestris and B. pubescens were minor dietary components in all seasons. A higher proportion of grasses, sedges, and rushes was found in the diet of lactating females. Results suggest that when an alternative browse species such as C. vulgaris is widely available, mountain hares may not have a large impact on the establishment of native woodland. The dietary results from this study are in broad agreement with those from previous studies using other techniques.

scholarly journals Root-Associated Mycobiomes of Common Temperate Plants (Calluna vulgaris and Holcus lanatus) Are Strongly Affected by Winter Climate Conditions

2021 ◽  
Author(s):  
Mathilde Borg Dahl ◽  
Derek Peršoh ◽  
Anke Jentsch ◽  
Jürgen Kreyling
Keyword(s):  
Soil Temperature ◽  
Plant Species ◽  
High Throughput Sequencing ◽  
Calluna Vulgaris ◽  
Absolute Temperature ◽  
Snow Accumulation ◽  
Temperature Variability ◽  
Holcus Lanatus ◽  
Soil Frost ◽  
Winter Climate

AbstractWinter temperatures are projected to increase in Central Europe. Subsequently, snow cover will decrease, leading to increased soil temperature variability, with potentially different consequences for soil frost depending on e.g. altitude. Here, we experimentally evaluated the effects of increased winter soil temperature variability on the root associated mycobiome of two plant species (Calluna vulgaris and Holcus lanatus) at two sites in Germany; a colder and wetter upland site with high snow accumulation and a warmer and drier lowland site, with low snow accumulation. Mesocosm monocultures were set-up in spring 2010 at both sites (with soil and plants originating from the lowland site). In the following winter, an experimental warming pulse treatment was initiated by overhead infrared heaters and warming wires at the soil surface for half of the mesocosms at both sites. At the lowland site, the warming treatment resulted in a reduced number of days with soil frost as well as increased the average daily temperature amplitude. Contrary, the treatment caused no changes in these parameters at the upland site, which was in general a much more frost affected site. Soil and plant roots were sampled before and after the following growing season (spring and autumn 2011). High-throughput sequencing was used for profiling of the root-associated fungal (ITS marker) community (mycobiome). Site was found to have a profound effect on the composition of the mycobiome, which at the upland site was dominated by fast growing saprotrophs (Mortierellomycota), and at the lowland site by plant species-specific symbionts (e.g. Rhizoscyphus ericae and Microdochium bolleyi for C. vulgaris and H. lanatus respectively). The transplantation to the colder upland site and the temperature treatment at the warmer lowland site had comparable consequences for the mycobiome, implying that winter climate change resulting in higher temperature variability has large consequences for mycobiome structures regardless of absolute temperature of a given site.

scholarly journals On the flora of honey plants of the Northern and Northwestern Altai regions within the Altai Territory

2019 ◽  
Vol 16 ◽  
pp. 00013
Author(s):  
Tatyana Kopytina ◽  
Galina Nenasheva ◽  
Marya Ivanova
Keyword(s):  
Plant Species ◽  
Botanical Composition ◽  
Floristic Richness ◽  
Maximum Content ◽  
North Western

The revision of honey plants in the regions’ floras and nature objects is regularly made for estimation of melliferous capacity of the territory. The article is devoted to the investigation of the melliferous flora of Northern and North-Western Altai in the area of Altai Territory. The goal of the research was to reveal the botanical composition of authentic honeys. The representativeness of melliferous species among common floristic richness in the studied districts is the following: in Altaiskiy − 56.49 %, Smolenskiy − 60.17 %, Soloneshenskiy − 53.61 %, Charyshskiy − 44.57 %. The examples of the botanical content of samples typical for each of these districts have been shown. In the angelica (djagilevyj) honey from Altajskiy district the maximum content of pollen belongs to the representatives from Apiaceae family 78.86 %. For the angelica (djagilevyj) honeys from surveyed districts the high content of pollen from the families Asteracerae, Brassicaceae, Fabaceae, Rosaceae are typical with different percentage in the samples. The article provides information on examples of wild-growing plant species including relicts, potential melliferous which pollen can be used as “marker” for determination of honey as Altai-origin.

scholarly journals Individuals from different-looking animal species may group together to confuse shared predators: simulations with artificial neural networks

2006 ◽  
Vol 274 (1611) ◽  
pp. 827-832 ◽  
Author(s):  
Colin R Tosh ◽  
Andrew L Jackson ◽  
Graeme D Ruxton
Keyword(s):  
Animal Species ◽  
Empirical Work ◽  
Species Group ◽  
Mixed Species ◽  
Retinotopic Maps ◽  
Species Groups ◽  
Artificial Neural ◽  
Mixed Species Groups ◽  
Species Grouping ◽  
Prey Items

Individuals of many quite distantly related animal species find each other attractive and stay together for long periods in groups. We present a mechanism for mixed-species grouping in which individuals from different-looking prey species come together because the appearance of the mixed-species group is visually confusing to shared predators. Using an artificial neural network model of retinotopic mapping in predators, we train networks on random projections of single- and mixed-species prey groups and then test the ability of networks to reconstruct individual prey items from mixed-species groups in a retinotopic map. Over the majority of parameter space, cryptic prey items benefit from association with conspicuous prey because this particular visual combination worsens predator targeting of cryptic individuals. However, this benefit is not mutual as conspicuous prey tends to be targeted most poorly when in same-species groups. Many real mixed-species groups show the asymmetry in willingness to initiate and maintain the relationship predicted by our study. The agreement of model predictions with published empirical work, the efficacy of our modelling approach in previous studies, and the taxonomic ubiquity of retinotopic maps indicate that we may have uncovered an important, generic selective agent in the evolution of mixed-species grouping.

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