2016 ACVIM Forum Research Abstract Program

Univariate and 2-factor repeated measures ANOVA were used to analyze data. Friedman tests were used for data sets that failed assumptions for ANOVA. Post hoc pairwise analyses were performed after ANOVA indicated significant (P < 0.05) effect. In foals given either treatment, there were significant (P < 0.05) effects of epinephrine on heart rate, pupil size, PCV and blood glucose. Sweating and arterial BP also increased significantly in control-but not erythromycin-treated foals. Significant treatment x time interaction was found only for sweating; pairwise comparisons were significant at every point after time 0. These results suggest that erythromycin does not cause generalized suppression of aand badrenergic responses. Anhidrosis may be a tissue-specific receptor or post-receptor effect of erythromycin and other macrolides. Vector-borne disease impacts the health and welfare of horses, worldwide. Recognized vector-borne diseases among horses include Anaplasmosis (Anaplasma phagocytophilum), Lyme Disease (Borrelia burgdorferi), Potomac Horse Fever (Neorickettsia risticii) and Piroplasmosis (Babesia caballi /Theleria equi). Additionally, Bartonella, Ehrlichia, Rickettsia, and hemotropic Mycoplasma species have been detected in horses with clinical disease spectrums ranging from nonclinical to fatal. The goal of this study is to investigate serological and molecular (PCR) tests that will detect vector-borne disease (VBD) pathogens in horses and apply a broad diagnostic panel to gain a more definitive picture of vectorborne equine pathogens, including novel species and co-infections. Three populations of horses were used to test serological and molecular diagnostic tests. Group I (n = 16): EDTA-whole blood (WB) and serum (S) sets from clinically healthy horses pastured in North Carolina with no clinical suspicion of VBD; Group II (n = 20): WB and S sets from horses submitted for diagnostic testing to the VBDDL, where presumably the clinician suspected vector-borne disease; Group III (n = 15): WB from horses in M erida, Nicaragua with a high degree of tick exposure. Serologic and PCR testing were performed retrospectively. DNA was extracted from WB, and qPCR assays were performed to test samples for infection by bacterial species within the following genera: Anaplasma, Babesia, Bartonella, Ehrlichia, Mycoplasma, Neorickettsia, Rickettsia and Theilera. For samples with positive results, the infectious agent was speciated by species-specific qPCR assay of the sample and/or DNA sequencing of the PCR amplicon. Seroreactivity to Babesia, Bartonella, Neorickettsia and Rickettsia antigens was determined using IFA, and seroreactivity to 3 Ehrlichia species, 2 Anaplasma species and B. burgdorferi antigens was determined using both a commercially available SNAP Ã’ 4DX Ã’ Plus ELISA and a research-based SNAP Ã’ MA ELISA. The combined use of serological and molecular assays in this study gave evidence of infection (by PCR) or exposure (by seroreactivity) to Anaplasma, Babesia, Bartonella, Borrelia, Ehrlichia spp., Theileria, and Rickettsia spp. None of the samples contained DNA from Mycoplasma spp. and two samples were positive for infection by Rickettsia felis, constituting the first reported instances of equine infection with R. felis detected by PCR. A novel Equine Ehrlichia species, reported in horses from Nicaragua, was detected in additional Nicaraguan horse samples from this study by both PCR, IFA and ELISA. This study highlights the wide-range o