Purine derivatives in urine and plasma of lactating cows given different levels of feed intake

Author(s):  
Z. M. Daniels ◽  
X.B. Chen ◽  
D.J. Kyle ◽  
K. Sinclair ◽  
E.R. Ørskov

It has been demonstrated in previous work (Chen et al 1993) that the molar ratio of purine derivatives (PD) to creatinine (C) in spot urine samples can be used as an index of microbial protein supply in sheep. This study was to examine the feasibility of using this approach in cattle.Twelve lactating beef cows were allocated into three groups and each group was fed one of the following levels of restricted feeding: (1) 13 kg fresh weight (FW)/d (high), (2) 10 kg FW/d (medium); (3) 7 kg FW/d(low), given in two equal meals. The diet was pelleted and contained (on fresh weight basis): 0.40 sodium hydroxide treated straw, 0.24 barley, 0.10 soya, 0.25 molassed sugar beet pulp and 0.01 urea. Daily urinary excretion of PD was measured for a week. Two-hourly collections of urine (regarded as ‘spot urine’) were also made over the same period for measurement of PD/C molar ratio. Plasma PD concentration was measured in three jugular blood samples taken on the last day of urine collection. Milk yield was indirectly measured by calf weights before and after suckling. The results were analysed to examine the variability of PD/C in spot samples and the relationship of the spot PD/C measurement with the daily PD output.

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 58-58
Author(s):  
Megan A Gross ◽  
Claire Andresen ◽  
Amanda Holder ◽  
Alexi Moehlenpah ◽  
Carla Goad ◽  
...  

Abstract In 1996, the NASEM beef cattle committee developed and published an equation to estimate cow feed intake using results from studies conducted or published between 1979 and 1993 (Nutrient Requirements of Beef Cattle). The same equation was recommended for use in the most recent version of this publication (2016). The equation is sensitive to cow weight, diet digestibility and milk yield. Our objective was to validate the accuracy of this equation using more recent published and unpublished data. Criteria for inclusion in the validation data set included projects conducted or published within the last ten years, direct measurement of forage intake, adequate protein supply, and pen feeding (no tie stall or metabolism crate data). The validation data set included 29 treatment means for gestating cows and 26 treatment means for lactating cows. Means for the gestating cow data set was 11.4 ± 1.9 kg DMI, 599 ± 77 kg BW, 1.24 ± 0.14 Mcal/kg NEm per kg of feed and lactating cow data set was 14.5 ± 2.0 kg DMI, 532 ± 116.3 kg BW, and 1.26 ± 0.24 Mcal NEm per kg feed, respectively. Non intercept models were used to determine equation accuracy in predicting validation data set DMI. The slope for linear bias in the NASEM gestation equation did not differ from 1 (P = 0.07) with a 3.5% positive bias. However, when the NASEM equation was used to predict DMI in lactating cows, the slope for linear bias significantly differed from 1 (P < 0.001) with a downward bias of 13.7%. Therefore, a new multiple regression equation was developed from the validation data set: DMI= (-4.336 + (0.086427 (BW^.75) + 0.3 (Milk yield)+6.005785(NEm)), (R-squared=0.84). The NASEM equation for gestating beef cows was reasonably accurate while the lactation equation underestimated feed intake.


Author(s):  
X. B. Chen ◽  
Adriana T. Mejia ◽  
D. J. Kyle ◽  
E. R. Ørskov

In ruminants, daily urinary excretion of purine derivatives (PD) reflects the absorption of microbial purines and can be used as an index of microbial protein supply (Chen, Ørskov and Hovell, 1991). The application could be extended to farm conditions if measurements based on spot urine samples or plasma could serve as an alternative index. The objective of this study was to examine whether PD concentrations in spot urine or plasma samples vary diurnally during a given feeding regime and if they reflect differences in daily PD excretion induced by varying feed intake.


Author(s):  
Kathleen B. Reuter

The reaction rate and efficiency of piperazine to 1,4-diazabicyclo-octane (DABCO) depends on the Si/Al ratio of the MFI topology catalysts. The Al was shown to be the active site, however, in the Si/Al range of 30-200 the reaction rate increases as the Si/Al ratio increases. The objective of this work was to determine the location and concentration of Al to explain this inverse relationship of Al content with reaction rate.Two silicalite catalysts in the form of 1/16 inch SiO2/Al2O3 bonded extrudates were examined: catalyst A with a Si/Al of 83; and catalyst B, the acid/phosphate Al extracted form of catalyst A, with a Si/Al of 175. Five extrudates from each catalyst were fractured in the transverse direction and particles were obtained from the fracture surfaces near the center of the extrudate diameter. Particles were also obtained from the outside surfaces of five extrudates.


2017 ◽  
Vol 95 (2) ◽  
pp. 884-891 ◽  
Author(s):  
G. V. Kozloski ◽  
C. M. Stefanello ◽  
L. Oliveira ◽  
H. M. N. Ribeiro Filho ◽  
T. J. Klopfenstein

2005 ◽  
Vol 14 (3) ◽  
pp. 317-346 ◽  
Author(s):  
TIMOTHY S. BROWN

This article examines the life and times of Richard Scheringer, an army officer and supporter of Adolf Hitler who became famous during the early 1930s for his high-profile conversion to communism. Known in the closing years of the Weimar Republic as a point-man for Communist efforts to win support from the radical right, Scheringer survived the Third Reich to become a leading figure in the postwar Communist Party. His well-documented but little-studied career, bridging critical caesurae of modern Germany history, highlights the unique political constellation of the interwar period, demonstrating fundamental continuities in the relationship of German communism to the nation before and after 1945.


1968 ◽  
Vol 48 (2) ◽  
pp. 129-137 ◽  
Author(s):  
A. R. Maurer ◽  
H. F. Fletcher ◽  
D. P. Ormrod

Pea plants growing in "weighing lysimeters" were subjected to five soil-water regimes to determine their response to varying conditions of soil water imposed at different stages of development. Plants subjected to a minimal water stress developed luxuriantly and continued to grow up to the harvest period. Pea yield and plant height were not reduced, but fresh weight and dry matter were less if irrigation was applied when soil water fell to 60% rather than 88% of that available. A severe water stress after blossom reduced pea yield, irrespective of soil-water conditions prior to blossom. Plants which had been given ample soil water before blossom wilted visibly when a severe stress was imposed in the post-blossom period, yet wilting did not occur in plants subjected to severe water stress both before and after blossom. Severe water stress prior to blossom did not cause a decrease in pea yield if ample soil moisture was made available after blossom.


Heliyon ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. e06420
Author(s):  
Caroline Azevedo Martins ◽  
Maria Conceição B dos Santos ◽  
Cassiano Felippe Gonçalves-de-Albuquerque ◽  
Hugo Caire Castro-Faria-Neto ◽  
Mauro Velho Castro-Faria ◽  
...  

2020 ◽  
pp. 33-43
Author(s):  
Olga N. Ratnicava ◽  
Irina P. Lisitsyna ◽  
Inna V. Аgeichik

Based on studies of geomorphology, stratigraphy, hydrology, various maps of Polesie, zones of influence of amelioration canals, vegetation maps, modern satellite images, as well as field studies of peatlands of Pripyat Polesie, two independent drainage systems have been identified, with a network of amelioration canals that intensively discharge water into the rivers Stwiga and Ybort`. Maps of key points were built In GIS-format, on which five sites were laid in the field within the Mezhch and Neresnya peat deposits for further long-term monitoring of GWL parameters. The locations of the sensors installation are based on the relationship of bog phytocenoses with the average annual GWL values and the amplitude of their fluctuations. Analysis of the GWL parameters before and after environmental rehabilitation measures will allow assessing the effectiveness of planned measures in disturbed areas and obtaining new data on areas of peat deposits in their natural state.


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