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Direct colloid osmometry in healthy New World camelids
Rolando J Quesada1, Maria Elena Gorman, Christopher K Cebra
1Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA. quesadar@ufl.edu
Veterinary Clinical Pathology
|May 11, 2011
Summary
Direct measurement of colloid osmotic pressure (COP) in alpacas and llamas is reliable using fresh or stored blood or plasma. This method offers objective fluid therapy monitoring for critically ill camelids.
Area of Science:
- Veterinary Medicine
- Physiology
- Biochemistry
Background:
- Direct colloid osmometry objectively assesses oncotic effects of fluid therapy.
- Essential for monitoring critically ill camelids prone to hypoproteinemia, edema, and ascites.
Purpose of the Study:
- Measure colloid osmotic pressure (COP) in alpacas and llamas.
- Correlate COP with total protein (TP), total solids (TS), and albumin+globulin (A+G) concentrations.
- Evaluate effects of sample type and storage on COP.
Main Methods:
- Collected heparinized blood from healthy alpacas and llamas.
- Measured COP in fresh whole blood and plasma using a membrane osmometer.
- Assessed correlations between COP and TS, TP, and A+G concentrations.
Main Results:
- No significant difference in median COP between alpacas and llamas.
- Sample type and storage conditions did not impact COP.
- Strong positive linear correlation between COP and TS, TP, and A+G in alpacas; best correlation with TS in llamas.
Conclusions:
- COP can be reliably measured in fresh or stored heparinized whole blood or plasma.
- Direct COP measurement is recommended for clinical and research settings.
- Further research needed to clarify COP-TP association in llamas.
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