Horses are prone to potentially lethal endotoxemia due to their surrounding fecal containing environment and their predisposition to colic. Their gastrointestinal tract and feces naturally contain gram-negative bacteria. These bacteria express lipopolysaccharide (LPS) on their cell membranes, which is recognized by Toll-like receptor 4 (TLR4). In cases where epithelial barriers are compromised or breached LPS has the potential to enter circulation and cause the inflammatory symptoms seen with endotoxemia. The objective of this study was to determine TLR4 presence and functionality on equine B cells. TLR4 expression on B lymphocytes has been studied in mouse, human and many other mammals, but has not been well characterized in the horse. Humans are highly sensitive to LPS but their B cells express non-functional TLR4. Mice in contrast are highly tolerant of LPS yet their B cells express functional TLR4. Studies in horse have perhaps been limited by the limited array of antibody markers available for use in horse. Anti-human CD21 has previously been shown to mark equine B lymphocytes. We show rat anti-mouse CD45R(B220) mAbs also accurately labels equine B lymphocytes. To investigate TLR4 expression in horses 12 Thoroughbred geldings, ages 5-10, were used for blood collection. By using the density gradient, Lympholyte, lymphocytes were separated from peripheral blood and incubated with or without LPS. B lymphocyte proliferation, TLR4 expression and mRNA changes were examined before or after culture in the presence or absence of LPS. We demonstrate TLR4 is expressed on equine B lymphocytes through the use of a mouse anti-human TLR4 antibody, clone 76B357.1, not previously used in horse. We demonstrated equine B cells fail to proliferate under LPS challenge as opposed to highly proliferative mouse B lymphocytes. However, transcriptional changes were observed in the equine cells within the TLR4 pathway upon treatment with LPS. / Master of Science

Equines have been used for utilized for manual labor, recreation, and companionship amongst many other valuable conveniences since their domestication. As the modern horse progressed from livestock to athlete, attention was paid to the body conformation to be used as an indicator of biomechanics and can dictate equine performance. Poor conformation can put physical limitations on the body and predispose the horse to injury and chronic disease. When not managed properly, these flaws can lead to injury, lameness, and premature retirement in sport horses. The distal limb is composed of tendons and ligaments that are all susceptible to tear or rupture. Protective wraps or boots are typically applied to the distal limb prior to exercise to prevent superficial injury from the environment or interference. However, these preventatives can trap heat against the skin which can have detrimental effects on the fibroblasts which can lead to failure. It was not until the early twentieth century that the idea of equine physiotherapy was adopted, and practices changed to meet remedial needs and create a sustainable, healthy equine athlete. Equine physiotherapy is a broad-spectrum term used to describe the therapeutic efforts made to keep the body in good health by means of prevention of injury to improve or maintain performance. Traditionally, therapeutics are administered by a veterinarian or trained professional in the event of an existing injury. In recent years therapeutics have been commercialized and are readily available for everyday preventative use. The most common readily available treatments being variations of pulsating electromagnetic fields (PEMF), vibration therapy, cryotherapy, and thermotherapy. When used prior to or after exercise, the therapeutics are designed to prepare the body for exercise and improve recovery by increasing circulation and down regulating the inflammatory response. The studies performed evaluate the efficacy of Rambo®Ionic (Horseware, Dundalk,Ireland), Lux Ceramic Therapy® (Schneider Saddlery Co., Inc., Ohio, USA), and Ice-Vibe® (Horseware, Dundalk,Ireland) therapeutic boots when applied to the distal limb as per manufacturer recommendation. The first study evaluated the therapeutic boots ability to alter performance performing gait analysis using the ALOGO™ MovePro (Alogo Technologies, Switzerland) stride sensor, blood analysis measuring serum concentrations of C reactive protein (CRP), basic fibroblast growth factor (bFGF) and tenascin-C (TN-C), and capturing thermal images of the distal limb using an HT-19 thermal imaging camera (HTI, La Vergne, TN). In this study, eight healthy horses were exercised for approximately ten minutes per day for five consecutive days. There was a ten-day washout period where the horse received no treatment between each period; there was a total of four periods. The second study only evaluated Rambo®Ionic (Horseware, Dundalk,Ireland) and Ice-Vibe® (Horseware, Dundalk,Ireland) therapeutic boots on seventeen healthy horses in the Virginia Tech equitation lesson program. There were three periods with five days of consecutive data collection and a ten-day washout period in between where the horses received no treatment. Gait analysis was measured using the ALOGO™ MovePro (Alogo Technologies, Switzerland) stride sensor and a blind behavioral analysis was performed to analyze behavioral changes under saddle in response to a rider. / Master of Science / Equines have been used for utilized for manual labor, recreation, and companionship amongst many other valuable conveniences since their domestication. As the modern horse progressed from livestock to athlete, attention was paid to the structure of the horse, otherwise known as conformation. Conformation is an indicator of physical movement and can dictate what uses the horse is best suited for. In undesirable cases, poor conformation can put physical limitations on the body and predispose the horse to injury and chronic disease. When not managed properly, these flaws can lead to injury, lameness, and premature retirement in sport horses. The distal limb is a particularly vulnerable structure. It is free of muscle and is comprised of tendons, ligaments, and mobile joints. A protective wrap or boot is typically applied to the distal limb prior to exercise which can have detrimental effects on the cellular components of the associated structures which can lead to failure. It was not until the early twentieth century that the idea of equine physiotherapy was adopted, and practices changed to meet remedial needs and create a sustainable, healthy equine athlete. Equine physiotherapy is a broad-spectrum term used to describe the therapeutic efforts made to keep the body in good health by means of prevention of injury to improve or maintain performance. Traditionally, therapeutics are administered by a veterinarian or trained professional in the event of an existing injury. In recent years therapeutics have been commercialized and are readily available for everyday preventative use. The most common readily available treatments being variations of pulsating electromagnetic fields (PEMF), vibration therapy, cryotherapy, and thermotherapy. When used prior to or after exercise, the therapeutics are designed to prepare the body for exercise and improve recovery by increasing circulation and down regulating the inflammatory response. The studies performed evaluate the efficacy of Rambo®Ionic (Horseware, Dundalk,Ireland), Lux Ceramic Therapy® (Schneider Saddlery Co., Inc., Ohio, USA), and Ice-Vibe® (Horseware, Dundalk,Ireland) therapeutic boots when applied to the distal limb as per manufacturer recommendation. The first study evaluated the therapeutic boots ability to alter performance performing gait analysis using the ALOGO™ MovePro (Alogo Technologies, Switzerland) stride sensor, blood analysis measuring serum concentrations of C reactive protein (CRP), basic fibroblast growth factor (bFGF) and tenascin-C (TN-C), and capturing thermal images of the distal limb using an HT-19 thermal imaging camera (HTI, La Vergne, TN). In this study, eight healthy horses were exercised for approximately ten minutes per day for five consecutive days. There was a ten-day washout period where the horse received no treatment between each period; there was a total of four periods. The second study only evaluated Rambo®Ionic (Horseware, Dundalk,Ireland) and Ice-Vibe® (Horseware, Dundalk,Ireland) therapeutic boots on seventeen healthy horses in the Virginia Tech equitation lesson program. There were three periods with five days of consecutive data collection and a ten-day washout period in between where the horses received no treatment. Gait analysis was measured using the ALOGO™ MovePro (Alogo Technologies, Switzerland) stride sensor and a blind behavioral analysis was performed to analyze behavioral changes under saddle in response to a rider.

Introduced cool-season grasses are dominant in Virginia's grasslands, but their high digestible energy and non-structural carbohydrate (NSC) levels pose a risk for horses prone to obesity and laminitis. Native warm-season grasses (NWSG) have lower digestible energy and NSC levels that may be more suitable for horses susceptible to laminitis. The overall objectives of this research were to 1) assess voluntary intake, toxicological response, and apparent digestibility of NWSG hays fed to horses; 2) evaluate the characteristics of three NWSG species under equine grazing; and 3) evaluate establishment strategies for NWSG and wildflowers in Virginia. For the first objective, a hay feeding trial was conducted with 9 Thoroughbred geldings in a 3 x 3 Latin square design. Voluntary dry matter intake of indiangrass (Sorghastrum nutans) and big bluestem (Andropogon gerardii) hays by horses were 1.3% and 1.1% of BW/d, significantly lower than orchardgrass (Dactylis glomerata), an introduced cool-season grass, at 1.7% of BW/d. Biomarkers for toxicity remained within acceptable ranges for all treatments. Apparent DMD did not differ among hays, ranging from 39 to 43%. Non-structural carbohydrate levels were below the maximum recommended concentration for horses susceptible to laminitis. For the second objective, a grazing trial was conducted comparing indiangrass (IG), big bluestem (BB), and eastern gamagrass (Tripsacum dactyloides) (EG) yields, forage losses, changes in vegetative composition, and effects on equine bodyweight. Nine, 0.1-hectare plots were seeded with one of the three native grass treatments, and each plot was grazed by one Thoroughbred gelding in two grazing bouts, one in July and another in September 2019. Indiangrass had the highest available forage, at 4340 kg/ha, compared with 3590 kg/ha from BB (P < 0.0001). Eastern gamagrass plots established poorly, and had only 650 kg/ha available forage during the experiment. Grazing reduced standing cover of native grasses in IG and BB treatments by about 30%, and trampled forage constituted 36-68% of groundcover in those plots after each grazing bout. Horses lost weight on all treatments, but tended (P=0.09) greater weight loss on the indiangrass treatment at 1.5 kg/d compared to 0.5 kg/d in the BB and EG treatments. For the third objective, three experiments were conducted to evaluate different strategies for establishing NWSG and wildflowers. The first experiment compared large grazed plots with or without a 2 oz/acre rate of the herbicide imazapic. Imazapic led to higher biomass and percent cover in plots seeded only with NWSG. For plots seeded with a mix of NWSG and wildflowers, imazapic reduced wildflower establishment and resulted in higher biomass and percent cover of weeds over the course of the experiment. The second experiment examined four rates of imazapic application for NWSG and wildflower establishment in small plots seeded with either NWSG or a NWSG and wildflower mix, and found biomass and percent cover of weeds was lowest at a 6 oz/acre rate, while NWSG biomass and cover did not differ between treatments. Wildflower establishment was again reduced by imazapic. The third establishment experiment compared four site preparation strategies for wildflower establishment and found tillage resulted in the most cover and biomass of wildflowers. / Doctor of Philosophy / Introduced cool-season grasses are dominant in Virginia's grasslands, but their high digestible energy and non-structural carbohydrate (NSC) levels pose a risk for horses prone to obesity and laminitis. Native warm-season grasses (NWSG) have lower digestible energy and NSC levels that may be more suitable for horses susceptible to laminitis. The overall objectives of this research were to 1) assess voluntary intake, toxicological response, and apparent digestibility of NWSG hays fed to horses; 2) evaluate the characteristics of three NWSG species under equine grazing; and 3) evaluate establishment strategies for NWSG and wildflowers in Virginia. For the first objective, a hay feeding trial was conducted with 9 Thoroughbred geldings in a 3 x 3 Latin square design. Voluntary dry matter intake of indiangrass (Sorghastrum nutans) and big bluestem (Andropogon gerardii) hays by horses were 1.3% and 1.1% of BW/d, significantly lower than orchardgrass (Dactylis glomerata), an introduced cool-season grass, at 1.7% of BW/d. Biomarkers for toxicity remained within acceptable ranges for all treatments. Apparent DMD did not differ among hays, ranging from 39 to 43%. Non-structural carbohydrate levels were below the maximum recommended concentration for horses susceptible to laminitis. For the second objective, a grazing trial was conducted comparing indiangrass (IG), big bluestem (BB), and eastern gamagrass (Tripsacum dactyloides) (EG) yields, forage losses, changes in vegetative composition, and effects on equine bodyweight. Nine, 0.1-hectare plots were seeded with one of the three native grass treatments, and each plot was grazed by one Thoroughbred gelding in two grazing bouts, one in July and another in September 2019. Indiangrass had the highest available forage, at 4340 kg/ha, compared with 3590 kg/ha from BB (P < 0.0001). Eastern gamagrass plots established poorly, and had only 650 kg/ha available forage during the experiment. Grazing reduced standing cover of native grasses in IG and BB treatments by about 30%, and trampled forage constituted 36-68% of groundcover in those plots after each grazing bout. Horses lost weight on all treatments, but tended (P=0.09) greater weight loss on the indiangrass treatment at 1.5 kg/d compared to 0.5 kg/d in the BB and EG treatments. For the third objective, three experiments were conducted to evaluate different strategies for establishing NWSG and wildflowers. The first experiment compared large grazed plots with or without a 2 oz/acre rate of the herbicide imazapic. Imazapic led to higher biomass and percent cover in plots seeded only with NWSG. For plots seeded with a mix of NWSG and wildflowers, imazapic reduced wildflower establishment and resulted in higher biomass and percent cover of weeds over the course of the experiment. The second experiment examined four rates of imazapic application for NWSG and wildflower establishment in small plots seeded with either NWSG or a NWSG and wildflower mix, and found biomass and percent cover of weeds was lowest at a 6 oz/acre rate, while NWSG biomass and cover did not differ between treatments. Wildflower establishment was again reduced by imazapic. The third establishment experiment compared four site preparation strategies for wildflower establishment and found tillage resulted in the most cover and biomass of wildflowers.

Determinations of cardiac output (CO) by M-mode echocardio-graphy were compared with simultaneous determinations by thermodilution in 2 conscious and 5 anesthetized horses. A range of cardiac outputs was induced by use of a pharmacological protocol (dopamine, 4 ug/kg/min, dobutamine, 4 ug/kg/min, and 10 ug/kg detomidine plus 20 ug/kg butorphanol, in sequence). Changes from baseline CO in response to each drug were evaluated, and data was analyzed to determine whether there were any interactions between drug treatment and measurement method. The mathematical relationship between CO as determined by M-mode echocardio-graphy (COecho) and as determined by thermodilution (COTD) was described and used to predict COTD from COecho. The 2 methods were compared with respect to bias and variability in order to determine the suitability of COecho as a substitute for COTD . Sources of the variability for each method were determined. Determination of CO by either method in standing horses was prohibitively difficult due to patient movement. The pharmacologi-cal protocol was satisfactory for inducing a range of cardiac outputs for the purpose of method comparison; however, use of dopamine did not offer any additional benefit over the use of dobutamine and was generally less reliable for increasing CO. Inclusion of detomidine provided an additional change in CO but did not increase the overall range of CO over that produced by halothane and dobutamine. COecho and COTD were significantly related by the predictive equation COTD = (0.63 +/- 0.157) x COecho + (16.6 +/- 3.22). The relatively large standard errors associated with COecho measurements resulted in a broad 95% prediction interval such that COecho would have to change by more than 100% in order to be 95% confident that the determined value represents true hemodynamic change. COecho underestimated COTD by a mean of 10 +/- 6.3 l/min/450 kg. The large standard deviation of the bias resulted in broad limits of agreement (-22.3 to +2.3 l/min/450 kg). Measurement-to-measurement variability accounted for 28% of the total variation in COTD values and 64% of the total variation in COecho values. Results might be improved if the mean of 3-5 consecutive beats was used for each measurement, but as determined in this experiment, COecho is too variable to have confidence in its use for precise determinations of CO. / Master of Science

Due to the detrimental side effects of NSAID administration, such as gastrointestinal ulceration and renal papillary necrosis, there is a profound need for clinical pain relief in horses with long term orthopedic disease whereby gastrointestinal side effects are obviated. Acetaminophen is one of the most commonly used analgesic drugs in humans, and is readily available as an inexpensive generic over-the-counter preparation. Acetaminophen has a number of mechanisms of action that differ from NSAIDs, including actions on the serotonergic, opioid, endocannabinoid and lipoxygenase pathways. These alternate pathways may provide greater efficacy against chronic or neuropathic pain in equine patients. Acetaminophen was preferred by physicians over COX-2 and nonselective NSAIDs, even when those drugs were coupled with proton-pump inhibitors to reduce gastrointestinal side effects; due to cost considerations and the occurrence of adverse side effects from those drugs. In horses, acetaminophen has been reported to be efficacious as an adjunct treatment for laminitis in one pony, and was an effective analgesic agent when combined with NSAIDs in a model of inducible foot pain. However, no studies have been performed to validate a dose-response curve in horses. A study recently completed by our group demonstrated rapid absorption following oral administration of acetaminophen. Reported human therapeutic plasma concentrations were achieved within 30 minutes of administration, with no clinical or clinicopathologic evidence of adverse side effects after two weeks of repeated dosing. Dose simulation trials indicate that a change in dosage schedule may be required in order to provide adequate plasma concentrations. / Master of Science / The use of non-steroidal anti-inflammatory drugs (NSAIDs) such as phenylbutazone in horses is widespread, and can be associated with detrimental side effects such as gastrointestinal ulceration and kidney damage. The clinical need for pain relief in horses with long-term lameness that minimizes gastrointestinal side effects has led to the development of cyclooxygenase-2 (COX-2) selective NSAIDs, such as firocoxib, but the expense of this therapy is often a major consideration limiting its use and few alternatives are available. Acetaminophen is one of the most commonly used analgesic drugs in humans, and is readily available as an inexpensive generic over-the-counter preparation. Despite the lower efficacy of acetaminophen in trials of human patients with chronic osteoarthritis, acetaminophen remains the preferred analgesic in humans due to its increased tolerance and improved cost-benefit analysis when compared to nonselective and COX2 selective NSAIDs. Acetaminophen has a number of mechanisms of action that differ from the current mainstays of equine analgesic therapy, which may provide greater efficacy against chronic or neuropathic pain in equine patients. A recent study of acetaminophen in horses has shown rapid absorption and achievement of levels reported to be therapeutic in humans, with no adverse side effects after two weeks of repeated dosing. In horses, acetaminophen has demonstrated efficacy as an adjunct treatment for laminitis in one pony, and was an effective analgesic agent when combined with NSAIDs in a model of inducible foot pain.

Establishment and maintenance of a successful pregnancy requires signaling from the embryo to the mare, a process known as maternal recognition. Six days after fertilization, the trophectoderm (TE), a placenta precursor is formed. Signals emanating from the TE to the uterine environment are critical to maternal recognition of pregnancy. The identity of factors necessary for this process remain unknown. A novel equine induced trophoblast cell line (iTr) that closely mimics the genotype and phenotype of native equine TE was created. Transcriptome analysis of iTr revealed increased expression of growth factor (GF) receptors for Epidermal GF (EGF), Hepatocyte GF (HGF), Fibroblast GF-2 (FGF-2) and Insulin GF (IGF-1), suggesting these GF may be important targets during TE development in the early embryo. We hypothesized that treatment of iTr cells with these GF would induce changes in cell proliferation and expression of genes likely involved in maternal recognition. The objectives of this experiment were to evaluate the effect of these GFs on iTr mitotic response and regulation of genes involved in steroidogenesis. Equine iTr cells (n = 3) were cultured with 10 ng/mL EGF, HGF, FGF-2 or IGF-1 for 24 hr, with 5-ethynyl-2'-deoxyuridine (EdU) supplementation during the final 2 hr. Subsequently, cells were fixed and EdU positive and total nuclei were enumerated. A parallel plate of iTr cells was treated in a similar manner and lysed for total RNA isolation. Quantitative PCR using gene-specific primers for CYP11A1, PTGS2, PTGES2, and PTGES3 was performed. Data were analyzed by ANOVA with Tukey's post hoc adjustment using the GLM procedure of SAS. Treatment with EGF, FGF-2, HGF, and IGF-1 increased (P < 0.05) iTr proliferation from control levels of 25.33 ± 1.03% to 38.58 ± 1.61%, 45.50 ± 2.94%, and 38.23 ± 2.01% respectively. The 2-&#916;&#916;CT method was used to calculate the fold change (FC) using GAPDH as the reference gene for normalization. Expression of CYP11A2, PTGES2, and PTGES3 was not affected by GF, as measured by qPCR. By contrast, PTGS2 transcript abundance increased (P < 0.05) following FGF-2 (FC = 3.327 ± 0.8291) and HGF (FC = 11.88 ± 4.572) treatment. These results indicate that FGF-2 and HGF may simultaneously induce proliferation and prostaglandin production by TE cells. The combined results of these experiments will improve our understanding of TE morphogenesis and its response to uterine-derived growth factors. / Master of Science / Establishment and maintenance of a pregnancy requires that the mare uterus recognize the presence of the embryo, a process known as maternal recognition of pregnancy. The trophectoderm (TE) are cells on the outer layer of the embryo formed six days after fertilization, which later give origin to the placenta. The TE sends signals from the embryo to the uterus, that are very important for the mare’s recognition of the embryo’s presence. The specific nature of these signals are still unknown in the horse. A cell line (iTr) very similar in aspect and genes to the horse’s native TE has been created in our laboratory. A set of comparative assays have showed that, during the developmental stage of maternal recognition, both the horse TE and the iTr cells share significant identity, and have receptors for the same set of growth factors (GF), suggesting these GF are important for early embryo development and potentially involved in the signaling process of maternal recognition. We proposed that treatment with these GF would induce iTr cells to proliferate and express signals likely involved in maternal recognition in horses. The objectives of this experiments were to evaluate the effect of EGF, HGF, FGF-2 and IGF-1 on iTr cells by measuring proliferation and cellular mechanisms of maternal recognition already established in in other species. Equine iTr cells were cultured with different GF and right before analysis a fluorescent dye that stain dividing cells was added in order to measure the proliferation. Equivalent cell cultures were used to evaluate if the treatment affected the production of hormones involved in signaling maternal recognition. Treatment with all GF induced higher cell proliferation, but HGF also increased the production of one enzyme that participates in producing a very important hormone (prostaglandin E2). The combined results of these experiments add to our understanding of maternal recognition in horses.

Flexor tendon lacerations in horses are traumatic injuries that can be career ending and life threatening. In the horse, a tendon repair must withstand the strains placed on the tenorrhaphy by immediate weight bearing and locomotion post-operatively. Despite the use of external coaptation, such strains can lead to significant gap formation, construct failure, longer healing time and poor quality of the healed tendon. Similar to equine surgery, gap formation and construct failure are common concerns in human medicine, with early return to post-operative physiotherapy challenging the primary repair. Early return to exercise and decreased gap formation has been shown to reduce adhesion formation. Based on these concerns, the ideal tenorrhaphy suture pattern for equines would provide: 1) high ultimate failure load, 2) resistance to gap formation, 3) minimal alteration in blood supply, and 4) minimal adhesion formation. Historically, various suture patterns and materials have been evaluated for human and equine flexor tendon repair. Results of equine studies suggest the three-loop pulley pattern (3LP) compares favorably to other patterns and is recommended for primary tenorrhaphy. However, this pattern still experiences significant gap formation and can result in failure. As a result, a technique which decreases the problems inherent in the 3LP is warranted for tenorrhaphy of equine flexor tendons. A review of the human literature highlights certain characteristics of the tenorrhaphy that may improve results including core purchase length and suture loop characteristics. Optimization of these tenorrhaphy characteristics can increase tenorrhaphy performance and patient outcome. The six-strand Savage technique (SSS) is a pattern routinely used in human hand surgery for tendon repair, and possesses high ultimate failure load and resistance to gap formation that may be beneficial for application in equine tendon repair. This study compared a novel tenorrhaphy pattern for horses, the SSS, with the currently recommended pattern, the 3LP, in an in vitro model. We hypothesize the SSS will fail at a higher ultimate load, resist pull through, and resist gap formation better than the 3LP. All testing used cadaveric equine superficial digital flexor tendons from horses euthanized for reasons other than musculoskeletal injury. All testing was approved by the IACUC. The two techniques were applied to cadaveric equine superficial digital flexor tendons. The same investigator performed all repairs (EE). Biomechanical properties were determined in a blinded, randomized pair design. Ultimate failure load, mode of failure and load required to form a 3mm gap were recorded on an Instron Electropuls materials testing system. Gap formation was determined using synchronized high-speed video analysis. Results are reported as mean + standard deviation. Statistical comparisons were made using Student's T test, with significance set at p<0.05. The tenorrhaphies were tested for their ultimate failure load and failure mode. The mean failure load for the SSS construct (421.1 ± 47.6) was significantly greater than that for the 3LP repaired tendons (193.7 ± 43.0). Failure mode was suture breakage for the SSS constructs (13/13) and suture pull through for the 3LP constructs (13/13). The maximum load to create a 3mm gap in the SSS repair (102.0N ± 22.4) was not significantly different from the 3LP repair (109.9N ± 16.0). The results of the current study demonstrate that the SSS tenorrhaphy has a higher ultimate failure load and resistance to pull through than the 3LP. The biomechanical properties of the SSS technique show promise as a more desirable repair for equine flexor tendons. However, in vivo testing of the effects of the pattern on live tissue and in a cyclic loading environment is necessary before clinical application of the pattern is recommended. / Master of Science

Like any other agricultural industry, many different career paths in the equine field are becoming more technologically advanced. To adapt to technological progress, current standards need to be integrated into school-based agricultural education courses to properly train and teach students about current industry standards. In addition to equine science curriculum development, emphasis must also be focused on providing assistance to secondary-school-based agriculture teachers so they can effectively teach industry-based equine science objectives in their programs. The equine curriculum objectives were measured in terms of perceived importance by equine professionals and post-secondary equine educators as well as Arizona school-based agriculture teachers. Further, the Arizona school-based agriculture teachers indicated their self-perceived ability to teach the objectives. Demographics for each group (equine industry professionals and Arizona school-based agriculture teachers) were also collected. A Borich needs assessment was calculated to prioritize areas needed for professional development of school-based agriculture teachers. Recommendations include the importance of bringing secondary-school-based agricultural education equine science curricula in line with industry standards. Further, providing professional development to secondary-school-based agriculture teachers is key to increasing teachers’ competence and ability to teach industry-based equine science.

Equine assisted psychotherapy (EAP) is an emerging experiential methodology<br />that has recently gained recognition as a method for addressing a range of presenting<br />problems for a wide variety of client populations. Couples therapy is one area that the<br />practice of equine assisted psychotherapy has recently gained traction. This study<br />describes the practice of equine assisted couples therapy in terms of practitioner<br />characteristics, approach to treatment, therapeutic goals and outcomes. Mental health<br />professionals currently using equine assisted psychotherapy to treat couples share their<br />experiences and perspectives to provide an overview of this emerging modality. / Master of Science

With overdose deaths and residential addiction treatment admittance increasing, more treatment options are necessary to meet the demand of services. Equine assisted psychotherapy and learning (EAPL) is a relatively new therapeutic tool in addiction treatment for individuals battling substance use disorder (SUD), and thus, lacks a solid evidence base to be implemented consistently and effectively. The purpose of this dissertation was to determine the effectiveness of EAPL in creating an emotionally safe environment for learning for college-age young adults with a particular focus on those struggling with SUD. This was accomplished in a series of projects focused on: 1) implementing evaluation methodology for tracking emotional safety and learning in young adults participating in equine interaction activities without therapeutic intentions, 2) determining the relationship between physiological responses and emotional safety and learning in young adults participating in outpatient EAPL programming for SUD, and 3) evaluating the treatment outcomes associated with emotional safety and learning for young adults with SUD participating in EAPL at a residential treatment facility. Each project utilized the same three evaluations for evaluating emotional safety and learning: 1) emotional safety evaluation, 2) equine knowledge exam, and 3) physical skills evaluation. In each of the studies, a correlation was found between emotional safety and equine knowledge and handling skills for college-age young adults, however, equine interaction with therapeutic intentions revealed a stronger correlation indicating it is not just the horse that provides the mental health benefits. An emotionally safe environment for learning, was established for college-age young adults within a residential treatment facility, this was not dependent on the length of stay or level of participation suggesting this is an efficient therapeutic option for SUD for this population. Emotional safety for the college-age young adults participating in EAPL was correlated to vital sign measurements, but vital sign measurements of young adults were independent of the vital signs of the therapy horse. Each of the three projects provided vital information filling the gap of knowledge surrounding EAPL as an effective clinical intervention strategy for SUD in college-age young adults and created a basis for further research using more objective measures.