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Published on: July 23, 2016
Analysis of aqueous humor obtained from normal eyes of llamas and alpacas
M L Aubin1, J R Gionfriddo, K R Mama
1Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523, USA.
Objective:
To evaluate composition of aqueous humor obtained from normal eyes of llamas (Lama glama) and alpacas (Lama pacos).
Sample Population:
Aqueous humor obtained from 10 male llamas and 10 male alpacas.
Procedure:
All animals had normal eyes, as determined by ocular examination. Aqueous humor samples were obtained via paracentesis of the anterior chamber of animals that were heavily sedated. Chemical analysis included measurement of concentrations of sodium, potassium, magnesium, chloride, bicarbonate, phosphorus, and glucose as well as osmolality and pH.
Results:
With the exception of potassium concentrations, values for aqueous humor composition did not differ significantly between llamas and alpacas. Mean +/- SD values for llamas and alpacas, respectively, were: sodium, 154.7 +/- 2.1 and 152.7 +/- 2.1 mEq/L; potassium, 5.3 +/- 0.4 and 4.6 +/- 0.4 mEq/L; magnesium, 1.8 +/- 0.1 and 1.7 +/- 0.1 mg/dl; chloride, 130.0 +/- 1.6 and 127.0 +/- 3.3 mEq/L; bicarbonate, 19.2 +/- 1.5 and 20.2 +/- 2.3 mEq/L; phosphorous, 2.7 +/- 0.3 and 2.5 +/- 0.4 mg/dl; glucose, 80.3 +/- 3.9 and 80.8 +/- 7.3 mg/dl; total protein, 29.0 +/- 8.6 and 31.5 +/- 10.1 mg/dl; and osmolality, 305.8 +/- 11.8 and 306.2 +/- 4.9 mOsm. The pH ranged from 7.5 to 8.0 for both species. Potassium concentrations were significantly higher in llamas than alpacas.
Conclusions And Clinical Relevance:
Except for potassium, composition of aqueous humor did not differ significantly between llamas and alpacas. Aqueous humor composition of llamas and alpacas is similar to that of other species that have been examined.
