TY  - JOUR
A1  - Bachmann, Lutz
A1  - Homeier, Timo
A1  - Arlt, Sebastian
A1  - Brueckner, Monika
A1  - Rawel, Harshadrai Manilal
A1  - Deiner, Carolin
A1  - Hartmann, Helmut
T1  - Influence of different oral rehydration solutions on abomasal conditions and the acid-base status of suckling calves
N2  - The aim of the study was to investigate the influence of oral rehydration solutions (ORS) on milk clotting, abomasal pH, electrolyte concentrations, and osmolality, as well as on the acid-base status in blood of suckling calves, as treatment with ORS is the most common therapy of diarrhea in calves to correct dehydration and metabolic acidosis. Oral rehydration solutions are suspected to inhibit abomasal clotting of milk; however, it is recommended to continue feeding cow's milk or milk replacer (MR) to diarrheic calves to prevent body weight losses. Three calves with abomasal cannulas were fed MR, MR-ORS mixtures, or water-ORS mixtures, respectively. Samples of abomasal fluid were taken before and after feeding at various time points, and pH, electrolyte concentrations, and osmolality were measured. The interference of ORS with milk clotting was examined in vivo and in vitro. To evaluate the effects of ORS on systemic acid-base status, the Stewart variables strong ion difference ([SID]), acid total ([A(tot)]), and partial pressure of CO2 (pCO(2)) were quantified in venous blood samples drawn before and after feeding. Calves reached higher abomasal pH values when fed with MR-ORS mixtures than when fed MR. Preprandial pH values were re-established after 4 to 6 h. Oral rehydration solutions prepared in water increased the abomasal fluid pH only for 1 to 2 h. Oral rehydration solutions with high [SID3] ([Na+] + [K+] - [Cl-]) values produced significantly higher abomasal pH values and area under the curve data of the pH time course. Caseinomacropeptide, an indicator of successful enzymatic milk clotting, could be identified in every sample of abomasal fluid after feeding MR-ORS mixtures. The MR-ORS mixtures with [SID3] values >= 92 mmol/L increased serum [SID3] but did not change venous blood pH. Oral rehydration solutions do not interfere with milk clotting in the abomasum and can, therefore, be administered with milk. In this study, MR-ORS mixtures with high [SID3] values caused an increase of serum [SID3] in healthy suckling calves and may be an effective treatment for metabolic acidosis in calves suffering from diarrhea.
Y1  - 2009
UR  - http://www.journalofdairyscience.org/
U6  - https://doi.org/10.3168/jds.2008-1487
SN  - 0022-0302
ER  - 
TY  - JOUR
A1  - Bauer, Monika
A1  - Hartmann, Lutz
A1  - Kleinpeter, Erich
A1  - Kuschel, Frank
A1  - Pithart, Cornelia
A1  - Weissflog, Wolfgang
T1  - Chiral Dopants Derived from Ephedrine/Pseudoephedrine: Structure and Medium Effects on the Helical Twisting Power
JF  - Molecular crystals and liquid crystals
N2  - Chiral dopants were obtained by acylation of enantiomerically pure ephedrine and pseudoephedrine with promesogenic carbonyl reagents. The products have been investigated with respect to their chiral transfer ability on nematic host matrices characterized by extreme differences of the dielectric anisotropy. It has been found that the medium dependence of the helicity induction nearly disappears at reduced temperatures. Based on variable temperature H-1 NMR studies on monoacylated homologues, the estimated coalescence temperatures and free activation enthalpies for the hindered rotation around C-N bonds could be correlated with the helical twisting power. Measurements by dielectric spectroscopy reveal the correlation between the molar mass of substituents linked to the chiral building block and the dynamic glass transition of corresponding chiral dopants. Furthermore, the effect of intramolecular and intermolecular hydrogen bonds has been studied by ATR-FTIR spectroscopy.
KW  - ephedrine/pseudoephedrine
KW  - Chiral dopants
KW  - ATR-FTIR
KW  - molecular structure
KW  - dielectric spectroscopy
KW  - H-1 NMR
Y1  - 2015
U6  - https://doi.org/10.1080/15421406.2014.949592
SN  - 1542-1406
SN  - 1563-5287
VL  - 608
IS  - 1
SP  - 14
EP  - 24
PB  - Routledge, Taylor & Francis Group
CY  - Abingdon
ER  -