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

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 lg/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.

The influence of sex, age and season on the haematological profile of alpacas (Vicugna pacos) in Central Europe

“…The above finding supports the theory that haematological reference intervals should be regularly reestablished to account for geographical and genetic variations (Passler et al 2013).…”

Metabolites related to renal function, immune activation, and carbamylation are associated with muscle composition in older adults

“…An elevated neutrophil/lymphocyte ratio may be reflective of an increased systemic microbial burden. For example, neutrophils increase in conjunction with decreased lymphocytes in response to LPS (Passler et al, 2013), and the neutrophil/lymphocyte ratio is elevated in association with increased levels of LPS-binding protein (LBP) (Lemesch et al, 2016). LPS decreases muscle protein synthesis and increases protein degradation (Orellana et al, 2006; Liu et al, 2013), an effect that would be expected to reduce the quantity of normal density muscle.…”

“…It is important to note that an elevated neutrophil/lymphocyte ratio may also be reflective of an increased circulating and/or systemic microbial burden. For example, neutrophils increase in conjunction with decreased lymphocytes in response to lipopolysaccharide (LPS) (Passler et al, 2013), a component of the outer wall of gram-negative bacteria (Rietschel et al, 1994), and in response to infection with gram-positive bacteria (Dolma et al, 2014) or virus (Holub et al, 2012). Similarly, serum levels of LPS-binding protein (LBP) are elevated in association with an increased neutrophil/lymphocyte ratio (Lemesch et al, 2016).…”

Assessment of the Acute Phase Response in Healthy and Injured Southern White Rhinoceros (Ceratotherium simum simum)

“…However, acute phase protein assays aimed at measuring human proteins, or marketed for multispecies use, have been used in numerous wildlife species and shown to have cross-reactivity (8,12,38). Choice of reagent is important, as antibody-based assays do not show the same reactivity, resulting in different abilities to detect the measurand (e.g., SAA) and different reference intervals (7,13,38,39). A modified approach to analytical validation of acute phase proteins conventionally includes demonstration of linearity (which is an indicator of accuracy), estimates of assay imprecision, and determination of differences in APR concentrations between a healthy and diseased group of animals known to have an inflammatory process (6,8,10,12,13,40).…”