PARALLELS BETWEEN BIODIVERSITY AND HUMAN DIVERSITY: A MANDATE TO IMPROVE ECOLOGICAL AND ORGANIZATIONAL HEALTH AND VITALITY.

The veterinary medical profession-including in marine biology and oceanography, ecology, conservation science, and zoo, wildlife, aquatic, and exotic animal medicine-suffers from a well-known lack of diversity. It is the author's view that in order to ensure that animals (and plants) have the environment they need to thrive, and to address urgent ecosystem health and conservation issues in our global interconnected communities, our wildlife, zoo, and conservation science organizations must embrace diversity, equity, inclusion, and belonging (DEIB). Just as biodiversity is critical for the health and vitality of our ecosystem, the diversity of the people who care for those ecosystems will protect the health and vibrancy of our professions and organizations. Though research may not yet have established a direct link between the diversification of such organizations and the advancement of biodiversity, that does not mean there is no such effect or impact. With myriad evidence that diverse organizations are better at solving complex problems, why would there be an expectation that these professions would fare differently? A call to action is for such organizations to conduct and publish research regarding the impact of increased human diversity on their missions of enhancing biodiversity. The challenges to biodiversity are great, and our organizations must use every tool in the toolkit to find solutions-including enhancing DEIB. This article elaborates on the many benefits that come with prioritizing DEIB in our organizations-similar to those benefits arising from healthy, biodiverse ecosystems. Potential action steps are shared that organizations and associations may consider in promoting DEIB and igniting progress.

Effects of a cognitive-behavioral skills building program on the mental health outcomes and healthy lifestyle behaviors of veterinary medicine students.

OBJECTIVE: To evaluate the effects of a cognitive-behavioral skills building program (ie, MINDSTRONG; The Ohio State University) on the mental health outcomes and healthy lifestyle beliefs and behaviors of Doctor of Veterinary Medicine (DVM) students. Sample: DVM students (n = 62) before beginning their program at a large public Midwest land-grant university. Procedures: All 171 incoming DVM students (class of 2024) were required to take the cognitive-behavioral skills building program (7 weeks in length) before starting their 2020 school year. Students were given the option to consent to the study portion of the program. Consenting participants completed a pre- and postsurvey containing demographic questions and 5 valid and reliable scales, including the Patient Health Questionnaire-9 that assesses depressive symptoms, the Generalized Anxiety Disorder-7 that evaluates anxiety, the Brief Inventory of Perceived Stress that measures stress, and the Healthy Lifestyle Beliefs and Healthy Lifestyle Behaviors scales. Descriptive statistics described sample characteristics, paired t tests assessed changes over time in the outcomes Personal Wellness Assessment, and Cohen's d determined effect sizes. Results: 62 DVM students completed both surveys. Postintervention, students had significant improvements in depressive symptoms, anxiety, and healthy lifestyle beliefs and behaviors. Clinical Relevance: Although this study used a small convenience sample of DVM students from a single university, a cognitive-behavioral skills building program demonstrated the ability to decrease rates of depression, anxiety, and suicidal ideation and improve healthy lifestyle beliefs and behaviors. Requiring DVM students to participate in such programming could provide benefit during their professional education and throughout their careers.

Supporting diversity, equity, inclusion, and belonging to strengthen and position the veterinary profession for service, sustainability, excellence, and impact.

Advancing equality and equity in society is creating positive change, and the time has come to critically evaluate veterinary medicine, which, by all metrics, lacks diversity. To keep pace with increasingly diverse demographics and recent surges in pet ownership among all racial/ethnic groups, significant efforts to enhance diversity, equity, inclusion, and belonging (DEIB) must occur in veterinary colleges and the profession. Recruiting more underrepresented students, building pipelines for diverse faculty/staff, and creating inclusive, welcoming environments where all can thrive are critical steps toward enhancing DEIB within our organizations and profession. Our goal is to share experiences and lessons learned from our intentional commitment to strengthen DEIB, with the hope that our journey will be helpful to others. Increasing diversity in the veterinary profession will be facilitated through removing barriers, creating inclusive work environments where all people feel they belong, and ensuring fair and equitable hiring and personnel management practices. These steps should in turn improve access and quality of veterinary care, ensure we are more representative of the communities we serve, increase revenue, and preserve the human-animal bond. "You cannot change any society unless you take responsibility for it, unless you see yourself belonging to it, and responsible for changing it." - Grace Lee Boggs.

Transcriptional changes associated with recurrent airway obstruction in affected and unaffected horses.

OBJECTIVE: To identify differentially expressed genes in pulmonary tissues of horses affected with summer pasture-associated obstructive pulmonary disease (SPAOPD), which is a form of recurrent airway obstruction (RAO), compared with those of unaffected horses. ANIMALS: 6 horses with SPAOPD-RAO and 6 unaffected (healthy) horses. PROCEDURES: Horses were assigned to 2 groups on the basis of medical history, clinical score, and transpleural pressure. Total RNA from each of the 5 lung lobes of each of the 6 SPAOPD-RAO-affected horses was extracted and pooled. Similarly, total RNA from unaffected horses was pooled. Differential display (DD) PCR assay was performed, and differentially expressed bands were purified and cloned into a plasmid vector. Plasmids were extracted from recombinant colonies, and purified DNA was sequenced. Genes of interest for RAO pathogenesis were identified. Real-time PCR assay was performed to confirm findings for the DD PCR assay. RESULTS: 18 differentially expressed genes (17 upregulated and 1 downregulated) were identified. Three genes of particular interest were found to be altered (2 upregulated and 1 downregulated) in horses with SPAOPD-RAO by use of real-time PCR assay, and these findings matched the differential expression found by use of the DD PCR assay. CONCLUSIONS AND CLINICAL RELEVANCE: SPAOPD-RAO in horses is a multifactorial, complex disease involving several genes. Upregulated genes, particularly beta2-microglobulin, and the downregulated secretoglobin gene can serve as marker genes that may help to identify SPAOPD-RAO at an early age.

Use of serial laminar tissue collection via biopsy in conscious healthy horses.

OBJECTIVE: To determine the feasibility of performing serial laminar and skin biopsies on sedated horses and whether sampling affected adjacent tissues. ANIMALS: 6 horses. PROCEDURES: Laminar tissues were harvested via biopsy through the hoof wall from healthy conscious horses via sedation and regional anesthesia. Eight specimens were collected at 4 time points during 24 hours from a single foot. Laminar biopsy specimens were harvested with a 6-mm-diameter biopsy punch after burring through the horny corium to the stratum medium. Skin biopsy specimens were collected from an area proximal to the coronary band. All tissues were examined via light microscopy. Total RNA was extracted and quantified, and gene expression analysis was completed for 2 housekeeping genes and the inflammatory mediator cyclooxygenase-2. RESULTS: Laminar and skin biopsies yielded adequate specimens for histologic and gene expression evaluation. There was no extension of inflammation or detectable damage to adjacent tissues during the 24-hour period in either laminar or skin specimens as judged via histologic findings and cyclooxygenase-2 expression. Lameness and discomfort induced by the procedure were minimal. CONCLUSIONS AND CLINICAL RELEVANCE: Laminar biopsy provided a satisfactory method of collecting laminar specimens and allowed serial sampling of individual horses.

The need for veterinarians in biomedical research.

The number of veterinarians in the United States is inadequate to meet societal needs in biomedical research and public health. Areas of greatest need include translational medical research, veterinary pathology, laboratory-animal medicine, emerging infectious diseases, public health, academic medicine, and production-animal medicine. Veterinarians have unique skill sets that enable them to serve as leaders or members of interdisciplinary research teams involved in basic science and biomedical research with applications to animal or human health. There are too few graduate veterinarians to serve broad national needs in private practice; academia; local, state, and federal government agencies; and private industry. There are no easy solutions to the problem of increasing the number of veterinarians in biomedical research. Progress will require creativity, modification of priorities, broad-based communication, support from faculty and professional organizations, effective mentoring, education in research and alternative careers as part of the veterinary professional curriculum, and recognition of the value of research experience among professional schools' admissions committees. New resources should be identified to improve communication and education, professional and graduate student programs in biomedical research, and support to junior faculty. These actions are necessary for the profession to sustain its viability as an integral part of biomedical research.

Characterization of endothelin receptors in the peripheral lung tissues of horses unaffected and affected with recurrent airway obstruction.

The purpose of the study was to determine and compare the expression of endothelin (ET) receptors in the peripheral lungs of healthy horses and those affected with recurrent airway obstruction (RAO) using reverse transcriptase polymerase chain reaction (RT-PCR), real-time PCR, Western blot analysis, and immunohistochemical techniques. Two groups of horses (7 healthy and 7 RAO-affected) were selected from a pool of horses destined for euthanasia. The grouping of horses was based on the history, clinical scoring, and pulmonary function testing. After euthanasia, gross postmortem evaluation of the lungs was conducted, and lung samples were collected and either stored at -80 degrees C or fixed in zinc-formalin for 12 h. The RT-PCR was performed by using specific primers for ETA and ETB receptors, and beta-actin. To determine the relative gene expression real-time PCR was performed. To detect ET receptor protein expression, Western blotting and immunohistochemical studies were performed using polyclonal antibodies against ETA and ETB receptors and beta-actin. The ET receptor expression was determined by performing either densitometric analyses or scoring of immunostaining. Statistical analyses were performed to detect differences in receptor expression within and between the 2 groups. The results indicated that ET receptor expression, particularly ETB receptors, was significantly greater in the peripheral lungs of RAO-affected horses than in those of healthy horses. Clinical trials using ET receptor antagonists, particularly ETB antagonists might help in developing a therapeutic strategy to treat this career-ending disease.

Local and remote lesions in horses subjected to small colon distension and decompression.

The purpose of this study was to observe and characterize colonic and lung lesions in horses subjected to experimental distension and decompression of the small colon. Sixteen healthy adult horses were divided into 2 groups: 9 horses that were subjected to distension of the small colon by means of a latex balloon surgically implanted in the lumen and inflated to a pressure of 40 mm Hg for 4 h, and 7 horses in which the balloon was implanted but not inflated. Colonic biopsy specimens were collected before balloon implantation, at the end of the period of obstruction, and 1.5 and 12 h after decompression and were examined for hemorrhage, edema, and neutrophil infiltration; myeloperoxidase (MPO) activity and hemoglobin concentration were measured as well. At the end of the experiment, lung samples were also collected and examined for neutrophil accumulation and MPO activity. The mucosa was not affected by luminal distension; lesions were restricted to the seromuscular layer. Neutrophil accumulation and edema were observed in the samples from both groups of horses but were greater in those from the distension group, in which there was also hemorrhage, fibrin deposition, and increased MPO activity in the seromuscular layer. Similarly, there was greater accumulation of neutrophils in the lung samples from the distension group than in those from the sham-operated group, as determined by histologic evaluation and MPO assay. These findings provide new evidence of reperfusion injury and a systemic inflammatory response, followed by remote lesions, in horses with intestinal obstruction.

Pathophysiologic effects of phenylbutazone on the right dorsal colon in horses.

OBJECTIVE: To determine pathophysiologic effects of phenylbutazone on the equine right dorsal colon (RDC). ANIMALS: 12 healthy adult horses. PROCEDURES: A controlled crossover observational study was conducted. Clinical and serum variables, colonic inflammation (histologic grading), and measurement of myeloperoxidase (MPO) activity, malondialdehyde (MDA) and prostaglandin E(2) (PGE(2)) concentrations, ingesta volatile fatty acid (VFA) content, and arterial blood flow in the RDC were evaluated for a 21-day period in horses administered phenylbutazone (8.8 mg/kg, PO, q 24 h) or a control substance. RESULTS: Data from 8 horses were analyzed. Plasma albumin concentrations decreased significantly from days 10 to 21 during phenylbutazone treatment, compared with results during the same days for the control treatment. Phenylbutazone treatment caused neutropenia (< 3.0 x 10(3) cells/microL). No other clinical or hematologic abnormalities were detected for phenylbutazone or control treatments. Two horses developed colitis while receiving phenylbutazone. No significant differences were detected in the RDC between phenylbutazone and control treatments for MPO activity, MDA and PGE(2) concentrations, and histologic evidence of inflammation. Arterial blood flow in the RDC was significantly increased during phenylbutazone treatment, compared with values for the control treatment. Differences were identified in VFA production during phenylbutazone treatment, compared with the control treatment, with a decrease in acetic acid concentrations over time. CONCLUSIONS AND CLINICAL RELEVANCE: Prolonged phenylbutazone administration caused hypoalbuminemia, neutropenia, changes in RDC arterial blood flow, and changes in VFA production. Veterinarians should monitor serum albumin concentrations and neutrophil counts and be cautious when making dosing recommendations for phenylbutazone treatment of horses.

Comparison of chondrogenic potential in equine mesenchymal stromal cells derived from adipose tissue and bone marrow.

OBJECTIVE: To compare the chondrogenic potential of adult equine mesenchymal stem cells derived from bone marrow (MSCs) or adipose tissue (ASCs). STUDY DESIGN: In vitro experimental study. ANIMALS: Adult Thoroughbred horses (n=11). METHODS: BM (5 horses; mean [+/-SD] age, 4+/-1.4 years) or adipose tissue (6 horses; mean age, 3.5+/-1.1 years) samples were obtained. Cryopreserved MSCs and ASCs were used for pellet cultures in stromal medium (C) or induced into chondrogenesis+/-transforming growth factor-3 (TGFbeta(3)) and bone morphogenic factor-6 (BMP-6). Pellets harvested after 3, 7, 14, and 21 days were examined for cross-sectional size and tissue composition (hematoxylin and eosin), glycosaminoglycan (GAG) staining (Alcian blue), collagen type II immunohistochemistry, and by transmission electron microscopy. Pellet GAG and total DNA content were measured using dimethylmethylene blue and Hoechst DNA assays. RESULTS: Collagen type II synthesis was predominantly observed in MSC pellets from Day 7 onward. Unlike ASC cultures, MSC pellets had hyaline-like matrix by Day 14. GAG deposition occurred earlier in MSC cultures compared with ASC cultures and growth factors enhanced both MSC GAG concentrations (P<.0001) and MSC pellet size (P<.004) after 2 weeks in culture. CONCLUSION: Equine MSCs have superior chondrogenic potential compared with ASCs and the equine ASC growth factor response suggests possible differences compared with other species. CLINICAL RELEVANCE: Elucidation of equine ASC and MSC receptor profiles will enhance the use of these cells in regenerative cartilage repair.

Case-control study of risk factors for pasture-and endocrinopathy-associated laminitis in North American horses.

OBJECTIVE To investigate risk factors for the development of pasture- and endocrinopathy-associated laminitis (PEAL) in horses and ponies in North America. DESIGN Case-control study. ANIMALS 199 horses with incident cases of PEAL and 351 horses from 2 control populations (healthy horses [n = 198] and horses with lameness not caused by laminitis [153]) that were evaluated in North America between January 2012 and December 2015 by veterinarian members of the American Association of Equine Practitioners. PROCEDURES North American members of the American Association of Equine Practitioners were contacted to participate in the study, and participating veterinarians provided historical data on incident cases of PEAL, each matched with a healthy control and a lameness control. Conditional logistic regression analysis was used to compare data on PEAL-affected horses with data on horses from each set of controls. RESULTS Horses with an obese body condition (ie, body condition score ≥ 7), generalized or regional adiposity (alone or in combination), preexisting endocrinopathy, or recent (within 30 days) glucocorticoid administration had increased odds of developing PEAL, compared with horses that did not have these findings. CONCLUSIONS AND CLINICAL RELEVANCE The present study identified several risk factors for PEAL that may assist not only in managing and preventing this form of laminitis, but also in guiding future research into its pathogenesis.

Serial alterations in digital hemodynamics and endothelin-1 immunoreactivity, platelet-neutrophil aggregation, and concentrations of nitric oxide, insulin, and glucose in blood obtained from horses following carbohydrate overload.

OBJECTIVE: To quantify changes in endothelium-derived factors and relate those changes to various aspects of digital hemodynamics during the prodromal stages of carbohydrate overload (CHO)-induced laminitis in horses. ANIMALS: 20 adult horses without abnormalities of the digit. PROCEDURES: Digital and jugular venous blood samples were collected at 1-hour intervals (for assessment of endothelin-1 [ET-1] immunoreactivity and measurement of glucose, insulin, and nitric oxide [NO] concentrations) or 4-hour intervals (CBC and platelet-neutrophil aggregate assessment) for 8 hours or 16 hours after induction of CHO-associated laminitis in horses treated with an ET-1 antagonist. Effects of treatment, collection site, and time and the random effects of horse on each variable were analyzed by use of a repeated-measures model. Where treatment and collection site had no significant effect, data were combined. RESULTS: Compared with baseline values, CHO resulted in changes in several variables, including a significant increase from baseline in digital blood ET-like immunoreactivity at 11 hours; digital blood ET-like immunoreactivity was significantly greater than that in jugular venous blood at 8, 9, 11, and 12 hours. Digital and jugular venous blood concentrations of glucose increased from baseline significantly at 3, 4, and 5 hours; insulin concentration increased significantly at 5 hours; and the number of platelet-neutrophil aggregates increased significantly at 12 hours. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, concurrent increases in venous blood ET-1 immunoreactivity, insulin and glucose concentrations, and platelet-neutrophil aggregates support a role of endothelial dysfunction in the pathogenesis of CHO-induced laminitis.

Effects of intramuscular administration of acepromazine on palmar digital blood flow, palmar digital arterial pressure, transverse facial arterial pressure, and packed cell volume in clinically healthy, conscious horses.

OBJECTIVE: To determine the magnitude and duration of effects of acepromazine administered intramuscularly (IM) on digital and systemic hemodynamic variables in clinically healthy horses. STUDY DESIGN: Experimental study. ANIMALS: Healthy adult horses (n=12). Methods- An ultrasonic Doppler flow probe was surgically implanted around the medial palmar digital artery before the study. Catheters were inserted in the transverse facial artery, lateral palmar digital artery, and jugular vein. A treatment group (n=6) was administered 0.04 mg/kg body weight of acepromazine IM; control horses (n=6) were administered an equivalent volume of saline IM. Palmar digital blood flow, and digital and facial arterial pressures were measured at baseline and for 6 hours after administration. Venous blood was collected for measurement of packed cell volume (PCV). RESULTS: Horses administered acepromazine had significantly lower facial arterial pressure compared with control horses administered saline. Palmar digital arterial blood flow in acepromazine-treated horses was not significantly different from that in control horses but increased significantly post-administration, compared with the respective baseline values for acepromazine-treated horses. PCV significantly decreased in horses administered acepromazine compared with their respective baseline value. CONCLUSION: IM acepromazine causes hypotension and increases palmar digital blood flow over time but the magnitude of the effect on digital blood flow was not sufficient to yield differences compared with saline-treated horses. CLINICAL RELEVANCE: IM acepromazine has a modest effect on palmar digital blood flow, facial arterial pressures and PCV in healthy horses with minimal sedation.

Characterization of equine adipose tissue-derived stromal cells: adipogenic and osteogenic capacity and comparison with bone marrow-derived mesenchymal stromal cells.

OBJECTIVE: To characterize equine adipose tissue-derived stromal cell (ASC) frequency and growth characteristics and assess of their adipogenic and osteogenic differentiation potential. STUDY DESIGN: In vitro experimental study. ANIMALS: Horses (n=5; aged, 9 months to 5 years). METHODS: Cell doubling characteristics of ASCs harvested from supragluteal subcutaneous adipose tissue were evaluated over 10 passages. Primary, second (P2), and fourth (P4) passage ASCs were induced under appropriate conditions to undergo adipogenesis and osteogenesis. Limit dilution assays were performed on each passage to determine the frequency of colony-forming units with a fibroblastic (CFU-F) phenotype and the frequency of ASC differentiation into the adipocyte (CFU-Ad) and osteoblast (CFU-Ob) phenotype. RESULTS: ASC isolates exhibited an average cell-doubling time of 2.1+/-0.9 days during the first 10 cell doublings. Approximately 1 in 2.3+/-0.4 of the total stromal vascular fraction nucleated cells were ASCs, based on the CFU-F assays, and 1 in 3.6+/-1.3 expressed alkaline phosphatase, an osteogenic marker. Primary ASCs differentiated in response to adipogenic (1 in 4.9+/-5.4, CFU-Ad) and osteogenic (1 in <2.44, CFU-Ob) inductive conditions and maintained their differentiation potential during subsequent passages (P2 and P4). CONCLUSION: The frequency, in vitro growth rate, and adipogenic and osteogenic differentiation potential of equine ASCs show some differences to those documented for ASCs in other mammalian species. CLINICAL RELEVANCE: Adipose tissue is a potential source of adult stem cells for tissue engineering applications in equine veterinary medicine.

Comparison of 2 endothelin-receptor antagonists on in vitro responses of equine palmar digital arterial and venous rings to endothelin-1.

The goals of this study were to determine the concentration-response (C-R) relationship of endothelin-1 (ET-1), compare 2 ET-receptor antagonists and determine the antagonist concentrations that block the vasomotor effects of ET-1, and compare the effectiveness of ET-1 and previously studied vasoconstrictors in equine palmar digital arterial and venous rings in vitro. Vessel rings from 8 nonlaminitic horses were placed in Tyrode's solution, 1 side fixed to the floor of an organ bath and the other side fixed to a force-displacement transducer. Two separate studies were conducted: (I) incubation with a single ET-receptor antagonist (PD142893 or PD145065 at a concentration of 10(-7), 10(-6), or 10(-5) M), followed by determination of an ET-1 C-R curve (using concentrations of 10(-10) to 10(-6) M) for medial vessel rings; and (II) comparison of ET-1 with norepinephrine and histamine (10(-10) to 10(-6) M) and comparison of contractile responses of medial and lateral vessel rings. In study I, ET-1 administration caused pronounced and sustained concentration-dependent contraction of vessel rings; these contractile responses were decreased by 10(-5) M PD142893 and were completely blocked by 10(-5) M PD145065. Venous rings had greater apparent maximum contraction in response to ET-1 than arterial rings. In study II, the relative sensitivity of norepinephrine was found to be equivalent to that of ET-1, whereas that of histamine was lower. No significant differences were observed between responses of medial versus lateral vessel rings. Thus, ET-1 is a potent vasoconstrictor of equine palmar digital arteries and veins, and the ET-receptor antagonist PD145065 is more effective than PD142893 in inhibiting these contractile effects in vitro.