Approximately 4% of horses suffer from one colic episode per year. The outcome is fatal in 11% of cases. F2-isoprostanes are the "gold standard" for assessment of oxidative stress in vivo and have been used extensively to quantify lipid peroxidation in association with risk factors in various diseases in humans. Because horses with colic may have intestinal ischemia and/or inflammation characterized by oxidative stress and increased production of isoprostanes, measurement of isoprostane concentrations in colicky horses may be of clinical value. The purpose of this study was to gather preliminary data on the feasibility of using urine isoprostane concentrations as an early screening tool for the severity of colic and to determine the need for surgery. The long term goal of this investigation is to reduce the number of deaths due to colic by developing a stall-side test capable of identifying horses needing surgery as early as possible and expediting their timely referral. We hypothesized that urine isoprostanes and isoprostane metabolites would be significantly higher in horses with colic compared to normal horses and that they can be used an indicator for the need for surgical intervention. Urine samples were collected from 42 normal horses and 38 horses with colic (21 medical and 22 surgical). Urine isoprostane and isoprostane metabolite concentrations were measured by mass spectrometry and normalized by urine creatinine (Cr) concentrations. Statistical analysis was performed using a one way ANOVA (Tukey's post-hoc comparison) and a 2 sample t-test. Significance was set at P<0.05. Mean (± SD) concentrations of isoprostanes and isoprostane metabolites were significantly higher in urine samples of horses with colic (2.94 ± 1.69 ng/mg Cr and 0.31 ± 0.22 ng/mg Cr, respectively) compared to healthy horses (1.89 ± 1.39 ng/mg Cr and 0.22 ± 0.08 ng/mg Cr, respectively). Urine isoprostane metabolite concentrations were significantly higher in horses undergoing surgery (0.38 ± 0.28 ng/mg Cr) compared to healthy control horses and medically treated colic horses (0.26 ± 0.11 ng/mg Cr). Non-survivors had significantly higher mean urine isoprostane metabolite concentrations (0.47 ± 0.39 ng/mg Cr) compared to healthy control horses and surviving colic horses (0.29 ± 0.24 ng/mg Cr). Since urinary concentrations of isoprostane metabolites are increased in horses suffering from colic and in non-survivor colic horses, the measurement of urine concentrations of isoprostane metabolites may be an important prognostic indicator in equine colic. / Master of Science

This study was aimed at characterizing the apoptotic response equine small intestine subjected to experimental ischemia-reperfusion injury and determining if use of an angiotensin converting enzyme inhibitor (enalaprilat) would ameliorate the apoptotic response. It was designed to determine if mucosal epithelial cells undergo apoptosis during the ischemia phase and also examined if apoptosis is significantly exacerbated by reperfusion. It also investigated whether administration of enalaprilat decreased reperfusion injury secondary to reduced enterocyte apoptosis. Injury was induced using a low flow model of I-R. During celiotomy a single loop of jejunum was isolated and arterial flow decreased to 20% of baseline for one hour and complete occlusion for a second hour. Reperfusion was monitored for 3 hours. A control group (n=6) were not treated while the treatment group (n=6) received 0.5 mg/kg enalaprilat in 0.9% NaCl immediately following ischemia. Jejunal samples were taken prior to the induction of ischemia, immediately post-ischemia and at 1, 2 and 3 hours of reperfusion. Samples were evaluated for gross tissue pathology with standard hematoxylin and eosin staining, the presence of apoptotic cells via TUNEL staining, and gene expression of three apoptosis related genes (bax, bcl-2, p53) using qPCR. Serum enalaprilat and ACE concentrations were determined from blood samples drawn concurrent with jejunal sampling using HPLC/MS and standard HPLC. Plasma enalaprilat concentrations were comparable to previous reports in awake horses. Enalaprilat appeared to have no effect on serum ACE concentrations, however a significant spike in ACE concentration occurred in the treatment group at 1 hour of reperfusion (P=0.0001). Grade of mucosal damage was not significantly different between control and treatment groups at any time point. Subjectively apoptotic index appeared to be higher in the treatment group at end ischemia and during reperfusion. There were no changes in expression of p53 or bcl-2 in either group. Bax expression was significantly decreased (P= 0.02) in the control group at 2 hours of reperfusion. Based on our data administration of an ACE inhibitor during anesthesia in horses with an ischemic segment of intestine confers no protective benefit and may be associated with increased intestinal injury and apoptosis. Lack of expression of p53, bax and bcl-2 suggests another apoptotic mechanism in equine ischemic intestine. / Master of Science

In six, healthy, adult horses, the origin of the left internal carotid artery was isolated via a modified hyovertebrotomy approach. Normograde blood flow was occluded by placement of a tourniquet on the artery near its origin. Lumenal access was gained through placement of a distally directed introducer sheath and retrograde blood flow from the cerebral arterial circle was confirmed. An 8.5 mm diameter detachable latex balloon loaded onto a carrier catheter and placed within a guiding catheter was introduced into the internal carotid artery through the introducer sheath and advanced to the target occlusion site (the proximal curve of the sigmoid flexure of the internal carotid artery). The balloon was inflated with 0.5 ml of a radiopaque solution. Correct placement and inflation of the balloon were confirmed by intraoperative radiography. The balloon was then released and the guiding and carrier catheters withdrawn. Immediate embolization of the distal internal carotid artery was determined by lack of retrograde blood flow through the introducer sheath. The introducer sheath was withdrawn from the vessel and the proximal tourniquet was replaced with two ligatures. Horses were euthanized on day 30 and detailed gross and histopathologic examinations were performed. The balloons were easily placed into the target site and produced immediate occlusion of retrograde flow from the cerebral arterial circle. All balloons remained inflated in their original position throughout the study period. Mature thrombus formation and absence of clinically significant inflammation were consistent findings in all occluded internal carotid arteries at gross necropsy and histologic examination. / Master of Science

Injuries to the equine distal limb are common and often involve synovial, tendinous and/or ligamentous structures. Historically, lacerations involving the equine digital flexor tendons carried a poor prognosis for return to athletic function due to contamination of the site at presentation, involvement of multiple anatomic structures and the need for immediate weight bearing after surgery. The need for weight bearing after surgery places strain on the tenorrhaphy site that exceeds the strength of the repair itself. Extrapolation of complex, stronger tenorrhaphy patterns from human literature and applying them to equine patients has been challenging. Human tenorrhaphy techniques initially focused on strong repairs, which are able to match or exceed the strength of tendon itself. Adhesion formation is problematic in human flexor tenorrhaphies, as most injuries occur to tendons surrounded by synovial structures. Human literature now focuses on using repairs that provide initial strength, minimal damage to intrinsic tendon architecture, and allow for early mobilization. This treatment protocol has greatly improved the functional outcome of human tenorrhaphies. Recent studies have evaluated the strength of complex tenorrhaphy patterns in equine superficial digital flexor tendons, using modifications of the Savage technique. The newly evaluated patterns are stronger than previously tested and commonly used techniques, such as the three-loop pulley (3LP). A review of tendon vasculature across species and healing characteristics of tendons highlights the importance of intrinsic tendon vasculature in the healing process. Using tenorrhaphy techniques that preserve this vasculature may improve the clinical outcome in these cases. Only one study has previously evaluated the effect of tenorrhaphy patterns on intrinsic tendon vasculature in equine superficial digital flexor tendon. This study compared perfusion of intrinsic tendon vasculature of equine superficial digital flexor tendon (SDFT) after 3LP and six-strand Savage (SSS) tenorrhaphies. We hypothesized that the SSS technique would significantly decrease vascular perfusion compared to the 3LP technique. Under general anesthesia, eight pairs of forelimb SDFTs were transected and either SSS or 3LP tenorrhaphy was performed on each forelimb. The horses were heparinized, euthanatized, and forelimbs perfused with barium sulfate solution then fixed with formalin under tension. The tendons were transected every 5mm and microangiographic images were obtained using a Faxitron X-ray cabinet with computed radiography imaging. Microvascular analysis of sections proximal to the tenorrhaphy, throughout the tenorrhaphy and distal to the tenorrhaphy was completed using Image J software and a custom macro. A significant reduction in the number of perfused vessels was seen in the SSS compared to the 3LP at two locations within the tenorrhaphy (p=0.004 and 0.039). The SSS technique took on average 4.7 ± 0.9 times longer to place. The SSS technique causes a reduction in tendon perfusion compared to the 3LP, which may limit its clinical use. Further research is required to elucidate the clinical significance of this difference. / Master of Science

Objective: To assess the safety and efficacy of lyophilized milled human amnion as a wound dressing of experimentally created equine distal limb wounds. Animals: Four clinically normal adult horses (3 Thoroughbred and 1 Paint, median age 11 years) obtained via donation. Procedures: One forelimb of each horse was randomly assigned to the treatment group, and the contralateral limb was assigned as the control. Full-thickness skin wounds were created on each metacarpus. Treatment limb wounds were dressed with lyophilized, milled, human-derived amnion material delivered under triple antibiotic ointment. Control wounds were dressed with triple antibiotic ointment. All wounds were covered in non-adherent dressings and distal limb bandages were applied. Digital photographs were taken of the wounds at each bandage change, performed every 2-4 days throughout a 98-day study period. Biopsies were collected at days 7, 21, 35, and 84. Results: One horse developed unilateral cellulitis that resolved with additional treatment. All treatment limbs exhibited an inflammatory response characterized by focal edema and discharge from the wounds. Wounds were completely epithelialized in control limbs sooner than treatment limbs in all horses, although there was no statistical difference between control (mean 46.8 days) and treatment (mean 51.8 days) wounds. Histologic scores were better in control wounds than in amnion-treated wounds at all time points. Conclusions and Clinical Relevance: Because wounds treated with amnion material in this study exhibited an inappropriate inflammatory response that resulted in delayed time to wound closure, human lyophilized milled amnion is not recommended for use in equine wound management. / Master of Science / Poorly healing wounds can be debilitating in horses. Amnion-derived treatments have been used in the horse and other species and been shown to improve wound healing. The purpose of this project was to evaluate a specific human-derived amnion material in the horse to evaluate its safety and efficacy. After creation of standardized skin wounds, the test product was applied to one limb and compared to untreated wounds on the horse's opposite limb. We found that the amnion material in this study caused swelling and longer wound healing times in horses. Therefore, this particular material is not recommended for use on horse wounds.

Feeding a fat-containing diet to the exercising horse is a facile way to increase energy density without risking the complications associated with hydrolyzable carbohydrates. Fat adaptation may also result in increases in the utilization of free fatty acids for fuel during exercise and sparing of muscle glycogen. Phosphatidylcholine, the main component of lecithins, can influence muscle contraction and improve endurance capacity during exercise. When it is combined with corn oil in a total mixed ration, soy lecithin is both highly digestible and palatable to horses. Our objectives in this study were to compare the effects of incremental exercise and isocaloric control (CON), corn oil (CO), and a soy lecithin/corn oil (LE) diets on plasma free fatty acids (FFA), cholesterol, glycerol, triglyceride (TG), lactate, and glucose. Also three different statistical models were compared for goodness of fit to the lactate curve. Plasma lactate and glucose both increased slowly early in the incremental exercise test (IET), then increased rapidly as the work intensity increased. Both decreased during recovery. No effects of IET or diet were found for either of these variables. Plasma TG was unchanged during exercise, but increased rapidly during recovery. Plasma FFA decreased from resting early in the IET then remained steady throughout the remainder of exercise. During recovery a rapid increase was exhibited. Plasma glycerol was constant during exercise, but increased during recovery. Plasma cholesterol did not change during exercise or recovery. Diet affected plasma FFA. Plasma FFA were lower for the CO and LE diets than the CON diet during the IET. Plasma glycerol was lower for the CO diet than the CON diet during the IET, with the LE diet intermediate between the two. Plasma cholesterol was higher for the CO and LE diets than the CON diet during the IET. A segmented model and an exponential model were found to have a good fit to the lactate curve. A point of inflection for a rapid increase in plasma lactate during incremental exercise was discovered. When this model was applied to diet, no differences in lactate threshold were found between the diets. Some criteria for fat adaptation were met, namely diet affected plasma FFA, glycerol, and cholesterol. However diet did not affect plasma TG, lactate, or glucose. This indicates that the rate of fatty acid oxidation was increased following fat adaptation, but it did not affect the rate of glucose oxidation and glycolysis during exercise. A lactate threshold for the equine can be obtained using a broken line model. Further studies using this approach are needed to establish its correlation with performance. / Master of Science

Childhood trauma and post-traumatic stress disorder (PTSD) is a growing mental health concern in pediatric occupational therapy (OT). More than two thirds of children report at least one traumatic event by age sixteen. Of the children with at least one reportable trauma, an estimated 3-–15% of girls and 14-–43% of boys will go onto develop PTSD. The consequences of undiagnosed and/or untreated pediatric PTSD include negative long-term health implications through adulthood that negatively impact quality of life. Negative implications may include depression, anxiety, substance abuse, high-risk sexual behavior, chronic diseases, and even suicide. Children with PTSD experience chronic stress responses that inhibits their willingness and interest to socialize, process social information, and develop relational skills towards others while performing daily activities. A two-part solution is discussed in this dissertation that includes educating occupational therapy practitioners (OTPs) about the benefits of incorporating equines for children with trauma and PTSD and review of a proposed program evaluation study. The proposed program evaluation study will help contribute to provider knowledge and research gaps of how horses impact pediatric social skills and their mental health. This dissertation will also discuss a plan for program implementation, evaluation, funding, and dissemination.

Equine-assisted psychotherapy is emerging as a new alternative therapy method. As the field is new, there is limited amount of research looking at the current theoretical foundation being utilized in the therapeutic process. This study aims to explore the field of equine-assisted psychotherapy and its current theoretical foundation. The main question guiding this study was: What are the therapeutic theories and themes guiding the current practice of equine-assisted psychotherapy? The study consisted of six in-person qualitative interviews with current practitioners of equine-assisted psychotherapy. A short Likert-type scale was also used to quantitatively gather descriptive statistics about theories currently being used by these practitioners. The results of this study yielded interesting findings about the similarities between equine-assisted psychotherapy and traditional office therapy. The use of horses in therapy creates new dynamics to be addressed in the therapeutic process. The practitioners interviewed in this study agreed on many different aspects about the application of equine-assisted psychotherapy to clients displaying characteristics of trauma, anxiety, depression, and boundary issues, but also had dissenting opinions about other aspects of the practice. The generalist model of social work practice is utilized in the questionnaire. This method of questioning found that the use of the generalist model is applicable to the field of equine-assisted psychotherapy.

Equine Assisted Activities and Therapy (EAA/T) is a non-invasive treatment modality recommended by the medical and educational community for a subset of challenged children and adults. As its popularity increases, so too are the concerns among stakeholders and the medical and educational professions about its legitimacy as a treatment modality. The main concern being that EAA/T practitioners have not acquired the professional skills required and that the EAA/T treatment programmes are not evidence-based. The central question of this research focused on identifying Equine Assisted Activities and or Therapy (EAA/T) and creating an optimal learning curricula and more practical experience for future practitioners. In order to explore these issues an extensive multi-method research study was conducted to identify gaps in EAA/T curricula, which included a review of empirical data and different curriculum models. The Delphi Method (DM), a robust, qualitative, naturalistic, systematic and interactive research method was used to support the research. Part of the DM required an analysis of data, adaptation of issues and amendments to questions culminating in a collective consensus among EAA/T experts. The key research findings suggested that current training programmes use curricula with significant gaps resulting in poor professional knowledge formation, a lack of experiential learning, insufficient knowledge of equestrianism and an inability to use pedagogic paradigms. Other findings showed that curricula being used were not being built as an application of sound theoretical principles but rather, transmitted in a manner that does not motivate active and meaningful learning or promote the best practical experience. As a consequence, national organisations and academies dedicated to EAA/T training sidestep high standards and core values for the sake of membership and financial gain. This rigorous research study has highlighted gaps in current training practices and has made it possible to make recommendations for a future curriculum. Recommendations that suggest the future curriculum is built on sound theoretical principles developing foundation knowledge to operate EAA/T in all fields of practice. This could set new quality and performance benchmarks and provides EAA/T practitioners with adequate tools to connect best practices to people with real-life challenges.

Mental disorders are a prevalent health issue that has an extensive amount of variability in the quantity of disorders, affected populations, and treatment. There are a multitude of approaches or therapeutic methods used by the mental health community. Although each therapy is valuable in unique ways, each therapy may not be suitable to treat every disorder or client. Traditional approaches, such as talk therapy, are effective for certain individuals, whereas some clients may not respond well to any of the traditional talk therapies. When traditional therapies are not working, a referral can be made for a therapy that might suit the client better. Equine-Assisted Psychotherapy (EAP) is an experiential psychotherapy that has done well not only in assisting typical clients, but also with clients that have had trouble in traditional modes of therapy. This is a collaboration of current works and research in EAP, along with the knowledge base of a current licensed practitioner of EAP. The purpose is to lay out the fundamentals of EAP, which offers a different modality than traditional talk therapies. By crafting a better picture of EAP, perhaps it can kindle further research in its efficacy and guide additional mental health professionals towards this type of therapy.