EVALUATION OF 25-HYDROXYVITAMIN D IN HOFFMANN'S TWO-TOED SLOTHS (CHOLOEPUS HOFFMANNI) USING DRIED BLOOD SPOTS ANALYZED BY LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY.

Although biochemical analytes have typically been measured using serum or whole blood samples, an increasing number of assays are validated for measurement of analytes from dried blood spots (DBS) on filter paper. DBS techniques are minimally invasive, require only a small sample volume, and simplify processing, storage, and shipment of samples. These qualities make DBS-based assays ideal for sampling of wildlife species in both captive and field settings. In this study, a liquid chromatography-tandem mass spectrometry assay was evaluated for measurement of 25-hydroxyvitamin D in sloths. Paired serum and DBS samples were collected from nine healthy captive Hoffmann's two-toed sloths (Choloepus hoffmanni). Statistical analysis using Passing-Bablok regression analysis, Bland-Altman plots, and the Wilcoxon signed-rank tests found good agreement between 25-hydroxyvitamin D3 measurements in serum and DBS samples. Constant and proportional bias were absent. Results from this study support the use of DBS samples for the evaluation of vitamin D status in Hoffmann's two-toed sloths and provide a foundation for further studies to validate this technique.

Cell mediated immune response in goats after experimental challenge with the virulent Brucella melitensis strain 16M and the reduced virulence strain Rev. 1.

Brucella melitensis is the etiologic agent of brucellosis in small ruminants and a common cause of disease in humans. While the protective immune response against this pathogen has been well studied in the mouse model, little is known of the immune response triggered by B. melitensis infection in natural hosts. The objective of the present study was to evaluate the caprine immune response over the course of infection with virulent B. melitensis strain 16 M and reduced virulence vaccine strain Rev. 1. Pregnant goats were infected at 11-14 weeks of gestation with 8 × 106 or 8 × 107 CFU of B. melitensis. Changes in granulocyte, monocyte, and mononuclear cell numbers were monitored by flow cytometry. Proliferative and functional responses of CD4+ T cells and WC1+ γδ T cells were also studied. B. melitensis 16 M infection triggered a pro-inflammatory response characterized by increased numbers of granulocytes, monocytes, and lymphocytes. The relative lymphocytosis was comprised of increases in CD4+ but not WC1+ T cell types in most animals. Little proliferative response was observed in Rev. 1-infected goats. Analysis of lymphocyte function suggested a degree of potential CD4+ T cell anergy, with low levels of CD25 expression and unresponsiveness to mitogen stimulation noted post-infection. The components of the protective response elicited by the Rev. 1 vaccine strain remain undefined. The study suggests a potential WC1+ γδ T cell mediated response, with high percentages of γδ T cells found to produce IFN-γ at various time points over the course of Brucella infection.

Evaluation of shedding, tissue burdens, and humoral immune response in goats after experimental challenge with the virulent Brucella melitensis strain 16M and the reduced virulence vaccine strain Rev. 1.

Brucella melitensis is the causative agent of brucellosis in small ruminants and is of considerable economic and public health importance in many countries worldwide. The control of disease in humans depends on the control of disease in livestock; however, few counties with endemic B. melitensis infection have been able to successfully eradicate this pathogen. This underscores the need for further research on the pathogenesis of both virulent and vaccine strains of B. melitensis in the small ruminant host. The aim of the present study was to characterize clinical effects, tissue colonization, shedding, and humoral immune response following B. melitensis infection in goats. Both virulent (16M) and reduced virulence (Rev. 1) strains of B. melitensis were studied. Pregnant goats were infected at 11-14 weeks of gestation with 8 x 106 or 8 x 107 CFU of B. melitensis. Infection of goats with B. melitensis 16M resulted in an 86% abortion rate. This strain disseminated widely in pregnant does post-infection with none of the 15 sampled tissues spared from colonization. Importantly, we report the first isolation of B. melitensis from muscle tissue in ruminants. Pathogenesis of Rev. 1 infection was variable with two does showing minimal colonization and one doe exhibiting disease similar to that of animals infected with fully virulent 16M. Shedding of B. melitensis in milk occurred in all 16M- and Rev. 1- infected goats. In pregnant animals challenged with virulent B. melitensis, median time to seroconversion was 21 days; however, 2 animals did not seroconvert until after abortion.

Surgical procedures in pinniped and cetacean species.

Significant advances in veterinary diagnostic and surgical techniques have been made over the past several decades. Many of these advances, however, have not reached the field of marine mammal medicine. A number of limitations exist: risks of anesthesia, anatomical challenges, difficulties with wound closure, environmental constraints, equipment limitations, and perceived risks. Despite these limitations, surgical treatments have been successfully utilized in marine mammals. While surgery is performed in pinnipeds more frequently than in cetaceans, studies conducted in the 1960s and 1970s on dolphin sleep and hearing demonstrated that general anesthesia can be successfully induced in cetaceans. Since this pioneering work, a small number of successful surgeries have been performed in dolphins under both general anesthesia and heavy sedation. While these surgical procedures in pinnipeds and cetaceans have typically been limited to wound management, dentistry, ophthalmic procedures, fracture repair, and superficial biopsy, a number of abdominal surgeries have also been performed. Recently there have been pioneering successes in the application of minimally invasive surgery in marine mammals. Many of the anatomical challenges that almost prohibit traditional laparotomies in cetacean species and present challenges in pinnipeds can be overcome through the use of laparoscopic techniques. Due to the limited number of pinnipeds and cetaceans in captivity and, thus, the limited case load for veterinarians serving marine mammal species, it is vital for knowledge of surgical procedures to be shared among those in the field. This paper reviews case reports of surgical procedures, both traditional and laparoscopic, in pinnipeds and cetaceans. Limitations to performing surgical procedures in marine mammals are discussed and surgical case reports analyzed in an effort to determine challenges that must be overcome in order to make surgery a more feasible diagnostic and treatment option in the field of marine mammal medicine.