The effect of experimentally induced bronchopneumonia on the pharmacokinetics and tissue depletion of gentamicin in healthy and pneumonic calves : a thesis /
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| Format: | Thesis Book |
| Language: | English |
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[College Station, Tex.] :
[Texas A&M University],
[1989]
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| Subjects: |
| Abstract: | ABSTRACT: The effects of a bovine bronchopneumonia model on the pharmacokinetics and tissue residue depletion profiles of gentamicin in calves weighing 90-140 kg was explored. Two groups of heifer calves were used. The first was a normal control group, while the other group had bronchopneumonia induced. A scoring system was developed to evaluate the extent of disease in the two groups. A bimodal distribution of the serum pharmacokinetic parameters in the pneumonic group was caused by the effects of dehydration on the parameters. A significantly higher serum clearance was seen of gentamicin in the pneumonic group than the normal group (P < 0.05). The pharmacokinetic models used to fit the tissue concentrations varied from tissue to tissue and between groups. The power function was the best fit for normal group's renal cortex concentrations and lung concentrations and the grossly appearing diseased lung in the pneumonic group. A one-compartment model was the best fit for the pneumonic group's renal cortex concentrations, renal medulla concentrations in both groups, liver concentrations in both groups, and the grossly normal appearing lung in the pnumonic groups. Because the best model of a particular tissue's concentrations varied between groups, withdrawal periods normally determined in healthy animals may be inappropriate in diseased animals. Addition of several parameters (serum creatinine, serum urea nitrogen, albumin, fibrinogen, and total protein concentration, along with white blood cell counts, and central fluid volume, volume of distribution at steady state, the area under the serum concentration vs. time curve, serum clearance of gentamicin, and the elimination rate constant) to these tissue depletion models using multiple regression improved the prediction of a given tissue's concentraiton. Certain parameters (serum creatinine and severity of disease score on the kill day) consistently improved the prediction of the concentrations in different tissues. |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Veterinary Physiology." "Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of Master of Science August 1989". Approved as to style and content by: Scott A. Brown, Thomas M. Craig, Thomas D. Thomson, James D. McCrady. |
| Physical Description: | xi, 69 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |