• Open Access

Evaluation of Methods to Improve the Diagnosis of Systemic Inflammation in Alpacas

Authors


  • The work for this study was performed at College of Veterinary Medicine of Auburn University

Corresponding author: T. Passler, DVM, PhD, DACVIM, Department of Clinical Sciences and Pathobiology, College of Veterinary Medicine, JT Vaughan Large Animal Teaching Hospital, Auburn University, Auburn, AL 36849; e-mail: passlth@auburn.edu.

Abstract

Background

The stoic nature of alpacas and limitations of current diagnostic tests make early recognition of inflammatory diseases in this species challenging.

Objectives

In a model of mild systemic inflammation, this study evaluated the utility of different clinical and clinicopathologic variables as accurate predictors of inflammation in alpacas.

Animals

Twelve clinically healthy alpacas were randomly assigned to equal-sized treatment (TG) and control (CG) groups. After collection of initial blood samples (0 hour), lipopolysaccharide (LPS; 20 μg/kg/24 h) or saline was administered by SC osmotic mini-pumps (OMP) for 96 hours. Additional blood samples were collected at 12, 18, 24, 36, 48, 72, 96, 120, 144, and 240 hours and differential leukocyte counts and concentrations of globulin, albumin, iron, haptoglobin, and serum amyloid A were measured.

Results

Mild swelling was observed at OMP implantation sites in both groups. Other clinical signs of systemic inflammation were not observed. Total leukocytes, neutrophils, albumin, and globulin concentrations were not significantly different between groups. Compared with CG-alpacas, TG-alpacas had fewer lymphocytes (P = .0322), more band neutrophils (P = .0087), and higher neutrophil/lymphocyte ratios (P = .0295) during the first 96 hours of the study. During LPS administration, serum iron concentrations were significantly decreased in TG-alpacas (P < .0001). Haptoglobin concentrations of TG-animals exceeded those of CG-animals after removal of OMP (P = .0056). Serum amyloid A was not detectable in alpacas in this study.

Conclusion and Clinical Importance

These results indicated that neutrophil/lymphocyte ratios and serum iron concentrations are early indicators of inflammation in alpacas. Additional research is needed to evaluate the acute phase protein responses of alpacas.

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