scholarly journals The use of dosed and herbage n-alkanes as markers for the determination of herbage intake

1986 ◽  
Vol 107 (1) ◽  
pp. 161-170 ◽  
Author(s):  
R. W. Mayes ◽  
C. S. Lamb ◽  
Patricia M. Colgrove
Keyword(s):  
Perennial Ryegrass ◽  
Accurate Estimation ◽  
Once Daily ◽  
Herbage Intake ◽  
Cyclical Pattern ◽  
Unbiased Estimates ◽  
Grazing Sheep ◽  
Supplementary Feed ◽  
Palmitic Acids

SUMMARYThe recovery in the faeces of the n-alkanes of herbage (odd-chain, C27–C35) and of dosed artificial alkanes (even-chain, C28 and C32) was studied in twelve 4-month-old castrated male lambs. The lambs received three levels of cut, fresh perennial ryegrass or a mixed diet of perennial ryegrass (0·70) and a barley-based concentrate (0·30) (500–900 g D.M./day). C28 and C32 n-alkanes (130 mg each), absorbed onto shredded paper, were given once daily for 17 days to test whether the recoveries of herbage and dosed alkanes were similar to enable their use as markers for determining the herbage intake of grazing sheep. Stearic and palmitic acids (130 mg each) were given with the dosed alkanes to half of the animals with the objective of facilitating emulsification of the dosed alkanes within the digestive tract.With the exception of C27 n-alkane, the faecal recoveries of all alkanes were unaffected by diet, feeding level or emulsifying agent. Faecal recovery of odd- chain herbage n-alkanes increased with increasing C-chain length. The recovery of the dosed C28 n-alkane was slightly greater than the recoveries of both C27, and C29 n-alkanes of herbage. The recoveries of the dosed C32 n-alkane and the herbage C33-alkane were the same.The mean herbage intake estimated using C33 and C32 n-alkanes was identical to the actual herbage intake. Other alkane pairs gave slight underestimates of herbage intake ranging from 3·5% for the C28–C29 pair to 7·6% for the C27–C28 pair. No cyclical pattern of n-alkane excretion throughout the day was observed. Examination of daily variations in faecal alkane concentrations indicated that the start of alkane dosing should precede the sampling of faeces by at least 6 days.These results suggest that accurate estimation of herbage intake in grazing sheep is possible from the simultaneous use of dosed C32 and herbage C33 n-alkanes as markers.The method may be particularly useful in enabling unbiased estimates of herbage intake to be made in animals receiving supplementary feed.

Determination of herbage intake of suckling lambs using long-chain n-alkanes as markers

1986 ◽  
Vol 1986 ◽  
pp. 82-82
Author(s):  
R.V. Hayes ◽  
C.S. Lamb ◽  
Patricia M. Colgrove
Keyword(s):  
Perennial Ryegrass ◽  
Dry Matter ◽  
Adult Sheep ◽  
Automatic Feeder ◽  
Herbage Intake ◽  
Relative Absorption ◽  
Ad Libitum ◽  
Grazing Sheep ◽  
Long Chain

The n-alkanes of grass outioular wax (odd-chain, C25- C25) can be used simultaneously with dosed n-alkanes (C28or C32) as markers for estimating the herbage intake of grazing sheep if the faecal recoveries of both herbage and dosed markers are the same. In adult sheep the accuracy of herbage intake estimation is not affected by the inclusion of concentrate in the diet as long as the intake and alkane concentrations of the concentrate are known. If, similarly, the ingestion of milk does not interfere with the relative absorption of dosed and herbage alkanes the herbage intake of suckling lambs at pasture could be estimated. To evaluate the potential of the technique in suckling lambs the faecal recoveries of odd-chain herbage n-alkanes and of dosed dotriacontane (C32) were determined in lambs offered eves’ milk and freshly cut herbage.From 2 weeks of age seven individually-housed male lambs received 1 kg/day homogenised ewes’ milk (166 g/day dry matter (DM)) in 4 feeds from an automatic feeder. The milk Has obtained by daily hand-milking of East Friesland ewes and was stored at -20° until used. Freshly cut perennial ryegrass was offered to the lambs ad libitum from the age of 4 weeks. A 6-day total collection of faeces was carried out when the lamba were 10 weeks of age.

scholarly journals Determination of Environmental Factors for the Implementation of the Exploitability Index in Industrial Aggregate Mining Using Multi-Criteria Analysis

2021 ◽  
Vol 10 (4) ◽  
pp. 196
Author(s):  
Julio Manuel de Luis-Ruiz ◽  
Benito Ramiro Salas-Menocal ◽  
Gema Fernández-Maroto ◽  
Rubén Pérez-Álvarez ◽  
Raúl Pereda-García
Keyword(s):  
Environmental Factors ◽  
Environmental Factor ◽  
Human Life ◽  
Accurate Estimation ◽  
Analytic Hierarchy ◽  
Main Components ◽  
Hierarchy Process ◽  
Made In

The quality of human life is linked to the exploitation of mining resources. The Exploitability Index (EI) assesses the actual possibilities to enable a mine according to several factors. The environment is one of the most constraining ones, but its analysis is made in a shallow way. This research is focused on its determination, according to a new preliminary methodology that sets the main components of the environmental impact related to the development of an exploitation of industrial minerals and its weighting according to the Analytic Hierarchy Process (AHP). It is applied to the case of the ophitic outcrops in Cantabria (Spain). Twelve components are proposed and weighted with the AHP and an algorithm that allows for assigning a normalized value for the environmental factor to each deposit. Geographic Information Systems (GISs) are applied, allowing us to map a large number of components of the environmental factors. This provides a much more accurate estimation of the environmental factor, with respect to reality, and improves the traditional methodology in a substantial way. It can be established as a methodology for mining spaces planning, but it is suitable for other contexts, and it raises developing the environmental analysis before selecting the outcrop to be exploited.

Determination of the Discharge Coefficient of a Thin-Walled Orifice Used in Hydrostatic Bearings

2005 ◽  
Vol 127 (3) ◽  
pp. 679-684 ◽  
Author(s):  
S. Charles ◽  
O. Bonneau ◽  
J. Fre^ne
Keyword(s):  
Discharge Coefficient ◽  
Ad Hoc ◽  
Thrust Bearing ◽  
Accurate Estimation ◽  
Hydrostatic Bearing ◽  
Hydrostatic Bearings ◽  
Flow Through ◽  
Thin Walled ◽  
Experimental Bench

The characteristics of hydrostatic bearings can be influenced by the compensating device they use, for example, a thin-walled orifice (diaphragm). The flow through the orifice is given by a law where an ad hoc discharge coefficient appears, and, in order to guarantee the characteristics of the hydrostatic bearing, this coefficient must be calibrated. The aim of this work is to provide an accurate estimation of the discharge coefficient under specific conditions. Therefore an experimental bench was designed and a numerical model was carried out. The results obtained then by the experimental and theoretical approach were compared with the values given by the literature. Finally, the influence of the discharge coefficient on the behavior of a thrust bearing is examined.

Variation in the respiratory quotient of birds and implications for indirect calorimetry using measurements of carbon dioxide production

1995 ◽  
Vol 198 (1) ◽  
pp. 213-219 ◽  
Author(s):  
G Walsberg ◽  
B Wolf
Keyword(s):  
Carbon Dioxide ◽  
Power Consumption ◽  
Indirect Calorimetry ◽  
Respiratory Quotient ◽  
Current Knowledge ◽  
Bird Species ◽  
Passer Domesticus ◽  
Carbon Dioxide Production ◽  
Accurate Estimation

Determination of animal power consumption by indirect calorimetry relies upon accurate estimation of the thermal equivalent of oxygen consumed or carbon dioxide produced. This estimate is typically based upon measurement or assumption of the respiratory quotient (RQ), the ratio of CO2 produced to O2 consumed. This ratio is used to indicate the mixture of lipids, carbohydrates and proteins in the metabolic substrate. In this analysis, we report the RQ for two bird species, Passer domesticus and Auriparus flaviceps, under several dietary and fasting regimes. RQ commonly differed substantially from those typically assumed in studies of energy metabolism and often included values below those explainable by current knowledge. Errors that could result from these unexpected RQ values can be large and could present the primary limit to the accuracy of power consumption estimates based upon measurement of carbon dioxide production.

scholarly journals Potentiality of Periphyton-based Aquaculture Technology in Rice-fish Environment

2009 ◽  
Vol 1 (3) ◽  
pp. 624-634 ◽  
Author(s):  
S. K. Saikia ◽  
D. N. Das
Keyword(s):  
Common Carp ◽  
Stocking Density ◽  
Fish Culture ◽  
Arunachal Pradesh ◽  
Gut Content ◽  
Common Carp Cyprinus Carpio ◽  
Feed Source ◽  
Rice Fish ◽  
Supplementary Feed

Periphyton is being used traditionally as rich aquatic feed for fishes throughout the countries like Cambodia, West Africa, Srilanka, India and Bangladesh. In waterlogged rice environment, it can be judiciously utilized as feed source introducing periphytophagous fish. Studies supported rice straw as suitable substrate for periphyton growth. The study of gut content of Common carp (Cyprinus carpio L.) from a periphyton-based rice-fish culture system in Apatani Plateau of Arunachal Pradesh, India showed maximum of 60 genera of microflora and fauna with periphytic in nature. The farmers from this rice-fish culture practice are gaining an average fish production of 500kg ha-1 180 day-1 without employing any supplementary feed. Better selection and determination of appropriate stocking density of periphytophagous fish in waterlogged rice-fields might extend the rice-fish culture towards a sustainable and self-substrating periphyton based aquaculture (SSPBA) practice. Keywords: Periphyton; Sustainable agriculture; Rice-fish; Self-substrating; Common carp; Apatani plateau. © 2009 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v1i3.2114              J. Sci. Res. 1 (3), 624-634 (2009) 

scholarly journals Determination of the toxic threshold of lolitrem B in cattle eating endophye-infected perennial ryegrass

2007 ◽  
Vol 13 ◽  
pp. 399-402
Author(s):  
L. Blythe ◽  
C. Estill ◽  
J. Males ◽  
A.M. Craig
Keyword(s):  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Clinical Signs ◽  
Positive Control ◽  
Control Group ◽  
Crossbred Cattle ◽  
Testing Laboratory ◽  
Neotyphodium Lolii ◽  
Lolitrem B

Perennial ryegrass (Lolium perenne) straw is used as a feed for livestock and horses. Some straw is infected with the endophyte, Neotyphodium lolii, which produces lolitrem tremorgens. Ingesting of the toxin produces clinical "ryegrass staggers." A 28 day feeding trail was conducted using 61 Black Angus, pure and crossbred cattle. The cattle were fed one of three levels of lolitrem B in chopped perennial ryegrass straw ranging from 0 ppb up to 3058 ppb. Four Japanese Wagyu crossbred cattle were fed chopped ryegrass straw containing 1400 ppb lolitrem B. The cattle were evaluated and scored twice a day for clinical signs of gait difficulties. Cattle consuming 1400 ppb lolitrem B did not show any overt clinical signs. After 14 days, 7 out of 15 cattle in the 1954 ppb lolitrem B group showed clinical signs of ataxia, stiffness, and tremors as seen in ryegrass staggers. All of the cattle in the positive control group of up to 3058 ppb lolitrem B with a 4 week mean of 2574 ppb developed clinical signs of staggers. None of the Wagyu cattle at 1400 ppb lolitrem B developed clinical signs. A dose response curve was developed based on the results of this study coupled with a prior study for use in the testing laboratory. Keywords: lolitrem B, perennial ryegrass, Lolium perenne, endophyte fungus, Neotyphodium lolii, cattle, threshold levels

Wool production of grazing sheep supplemented with casein and formaldehyde-treated casein

1971 ◽  
Vol 11 (48) ◽  
pp. 9 ◽  
Author(s):  
JP Langlands
Keyword(s):  
Sodium Caseinate ◽  
Supplementary Feeding ◽  
Stocking Rate ◽  
Wool Production ◽  
Herbage Intake ◽  
Grazing Sheep

For 59 days grazing Merino wethers were given 0, 40, or 80 g of sodium caseinate each day directly into the abomasum. Clean wool production was increased by 35 and 38 per cent after giving 40 and 80 g per day respectively. In a second experiment grazing Merino wethers were given 0 or 80 g casein, or 40 or 80 g casein treated with formaldehyde (HCHO-casein) each day through cannulae inserted into the rumen. Wool production was increased by 22, 38, and 51 per cent by the 80 g casein, 40 g HCHO-casein and 80 g HCHO-casein treatments respectively. In a third experiment Merino wethers, in which rumen cannulae had been prepared, were grazed at a high and low stocking rate, and were given daily 0, 20, 40, or 60 g HCHO-casein through the rumen cannulae. Wool production and efficiency of wool production increased, and herbage intake declined as the level of supplementary feeding increased.

scholarly journals Use of an optical density ruler in measurements of dye-dilution curves

1964 ◽  
Vol 19 (2) ◽  
pp. 347-353 ◽  
Author(s):  
James B. Bassingthwaighte ◽  
Anthony W. T. Edwards ◽  
Earl H. Wood
Keyword(s):  
Indocyanine Green ◽  
Optical Density ◽  
Light Transmission ◽  
Accurate Estimation ◽  
Calibration Constant ◽  
Nonhomogeneous Media ◽  
Dye Dilution ◽  
Logarithmic Relationship ◽  
Dilution Curves

The inapplicability of Beer's law to densitometry of dyes in whole blood or other nonhomogeneous media has been long known. When using a densitometer whose output is directly proportional to the light transmitted, a simple transformation— log X = log (x – x0)—can be employed to allow rapid, accurate estimation of dye concentration. This is facilitated by use of an optical density ruler. The transformation, X = x – x0, can be made mechanically, by shifting the infinity position of the ruler with reference to the zero light transmission position, or electrically, by appropriate use of zero suppression in the densitometer circuit. The transformation results in an exponential (logarithmic) relationship between light transmitted and concentration of the dye (indocyanine green). Readings of relative optical density obtained by use of the ruler are multiplied by a calibration constant to calculate dye concentration. The principles of the transformation have been applied to the determination of the optimal zero suppression required for maintenance of constant sensitivity of the densitometer in the presence of various levels of background dye. densitometer calibration; indocyanine green densitometer; calibration of dye-dilution curves; correction of dye-dilution curves Submitted on September 13, 1963

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