Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:In Vitro Research
In vitro research involving horses refers to the study of equine cells, tissues, or biological molecules outside their normal biological context, typically in controlled laboratory environments. This research approach allows scientists to investigate cellular processes, molecular interactions, and the effects of various treatments without the ethical and logistical complexities of in vivo studies. In vitro studies contribute to understanding equine physiology, pathology, and pharmacology by providing insights into cellular responses to pathogens, drugs, and other stimuli. This page compiles peer-reviewed research studies and scholarly articles that explore various in vitro methodologies and their applications in equine science, including cell culture techniques, molecular assays, and drug efficacy testing.
Selective oncolytic activity of newcastle disease virus in equine sarcoid primary cells: a preclinical investigation. Equine sarcoids are the most common skin tumors in horses and are characterized by local invasiveness, high recurrence rates, and inconsistent responses to current therapies. Oncolytic virotherapy represents a promising alternative approach that exploits defects in antiviral signaling pathways in tumor cells. Newcastle disease virus (NDV), an avian paramyxovirus that is nonpathogenic in mammals, has demonstrated tumor-selective activity in several species; however, its effects on equine sarcoids have not been previously investigated. In this study, primary cell cultures derived from equine sar...
In Vivo Metabolite Formation and In Vitro Cytochrome P450-Mediated Metabolism of Vonoprazan in Horses. Vonoprazan is a potassium-competitive acid blocker with potential for the treatment of equine gastric ulcer syndrome. Vonoprazan metabolic pathways in horses have not been characterized. This study aimed to identify vonoprazan metabolites following oral administration and to determine the metabolic enzymes responsible for their metabolism using in vitro models. Six healthy adult Thoroughbred horses received vonoprazan (0.5 and 1 mg/kg PO) in a randomized crossover design. Plasma concentrations of vonoprazan-N-oxide (M-I) and vonoprazan-nitrone (M-III) were quantified using a validated liquid...
Antimicrobial effects of equine regenerative medicine products: A systematic review and meta-analysis of in vitro and in vivo studies. Equine regenerative medicine products involving platelet-rich plasma (PRP), mesenchymal stromal cells (MSCs), and their derivatives are increasingly explored for antimicrobial and therapeutic roles, but their efficacy and between-study variability remain unclear. Objective: To systematically review and meta-analyse in vitro and in vivo evidence on antimicrobial effects of equine regenerative medicine products and to evaluate their efficacy against key pathogens. Methods: Systematic review and meta-analysis: METHODS: We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses...
The in vitro application of high-intensity laser therapy on equine platelet-rich plasma and autologous protein solution does not alter select cytokine and growth factor concentrations. To quantify the effects of high-intensity laser therapy (HILT) on the concentration of key immunomodulatory cytokines and growth factors in equine platelet-rich plasma (PRP) and autologous protein solution (APS). We hypothesized that HILT treatment of PRP and APS in vitro would increase the concentration of cytokines and growth factors compared to untreated controls. Unassigned: Whole blood was collected from 6 adult horses housed at the University of Pennsylvania in March 2025 and processed into PRP or APS using commercially available systems (Zoetis). Platelet-rich plasma and APS samples wer...
Somatic cell nuclear transfer as a complementary tool for genetic conservation of the Peruvian Paso horse. The Peruvian Paso horse, a breed of national significance in Peru known for its unique gait, has been selectively bred for nearly 500 years and now faces potential risks due to reduced genetic diversity. To investigate the potential of somatic cell nuclear transfer to enhance genetic conservation strategies, a program was initiated to produce cloned Peruvian Paso foals. Skin biopsies from a highly awarded stallion with exceptional breed-defining traits were used as the source of donor somatic cells. Of the 15 cloned embryos reconstructed, seven blastocysts were produced, and five were transfer...
Efficiency of transvaginal oocyte aspiration (TVA), post-mortem ovary harvest (OH), and Intracytoplasmic Sperm Injection (ICSI) in a Quarter Horse mare population in North America. In a clinical setting, Intracytoplasmic Sperm Injection (ICSI)-derived equine blastocysts can be obtained either by transvaginal oocyte aspiration (TVA) or post-mortem ovary harvest (OH). Most peer-reviewed retrospective reports have described the suitability of these techniques for obtaining blastocysts, pregnancies, and live foals, particularly in Warmblood horse populations in Europe. In this study, retrospective data from Quarter Horse client-owned mares subjected to TVA-ICSI (n = 105; 151 cycles) or OH-ICSI (n = 42) at an academic institution in North America between 2023 and 2025...
Effects of equine sperm incubation under capacitation-supporting conditions on homologous and heterologous ICSI outcomes. Intracytoplasmic sperm injection (ICSI) in horses has become sufficiently efficient to be considered for clinical and commercial application; however, several factors influencing its efficiency remain poorly understood. This study evaluated whether incubating equine sperm under capacitating conditions induces capacitation-associated changes and affects embryo development following homologous equine ICSI, as well as oocyte activation, early cleavage, and 5-methylcytosine (5 mC) and 5-hydroxymethylcytosine (5hmC) levels following heterologous ICSI using bovine oocytes. Equine spermatozoa were ...
The effect of fenugreek (Trigonella foenum-graecum) on stallion spermatozoa motility and vitality in vitro. This study evaluated the effects of Trigonella foenum-graecum L. (fenugreek) seed extract on stallion spermatozoa quality in vitro, focusing on motility, vitality, and functional competence. In vitro spermatozoa analyses showed that fenugreek seed extract did not demonstrate overt cytotoxicity under the tested conditions: S1 = 1562 µg/mL; S2 = 781 µg/mL; S3 = 390.5 µg/mL; S4 = 195.25 µg/mL; S5 = 97.62 µg/mL; S6 = 48.81 µg/mL; S7 = 24.40 µg/mL. Computer-assisted semen analysis (CASA) revealed a concentration- and time-dependent Treatment × Time interac...
Effects of IGF1 Knockdown and Overexpression on the Phenotype and Function of Equine Primary Skeletal Muscle Cells. Skeletal muscle serves as the direct executor of movement, and the proliferation and migration capacities of its constituent cells represent the key physiological foundation determining equine endurance and speed. Previous whole-transcriptome analysis has shown that Insulin-like Growth Factor 1 () is significantly upregulated in following racing and is involved in the PI3K-Akt signaling pathway; however, its specific regulatory mechanism in equine skeletal muscle cells remains unclear. This study utilized primary equine skeletal muscle cells as a model. By constructing an overexpression plas...
Isolation of high-quality stallion spermatozoa: a comparison of methods and their effects on sperm quality and yield, DNA damage, and functional competence by ICSI. Intracytoplasmic sperm injection (ICSI) is the primary method for equine in vitro embryo production, yet outcomes may be influenced by sperm selection techniques. Objective: This study compared four isolation methods: EquiPure™, Vetmotl™, Felix™, and Samson™, to assess effects on sperm quality and embryo development. Methods: Semen was collected from four fertile stallions, processed and evaluated for sperm motility, viability, DNA integrity, and yield of high-quality cells relative to input. Isolated samples were compared to non-isolated (centrifuged) samples. Spermatozoa were used fo...
Sperm Energy-restriction and Recovery (SER) enhances equine sperm function and embryo development after ICSI. Assisted reproductive technologies (ART) are extensively used in domestic animal reproduction; however, improving their efficiency and consistency remains a major challenge for achieving reliable reproductive outcomes. The equine industry faces unique challenges related to sperm capacitation, which limited the success of conventional in vitro fertilization (IVF) for many years. Consequently, intracytoplasmic sperm injection (ICSI) became the most widely used technique for commercial in vitro embryo production. Even though a successful IVF protocol was recently developed, substantial opportunit...
Follicular growth and atresia at the time of oocyte aspiration differentially affect in vitro embryo production in mares. Ovum pick-up (OPU) followed by intracytoplasmic sperm injection (ICSI) is increasingly used in horses, yet embryo production rates remain variable, potentially reflecting differences in oocyte developmental competence at the time of aspiration. We investigated whether the stage of the follicular wave, growth phase (GP) versus atresia phase (AP), and associated endocrine profiles in mares, influence oocyte developmental competence. Mares underwent follicular ablation to synchronize follicular waves, and oocytes were aspirated during GP or AP for in vitro production of embryos. Serum concentrati...
Cracks in the ice: biological challenges and incremental progress in equine oocyte vitrification. Equine oocyte vitrification could enhance the flexibility of in vitro embryo production, yet developmental competence remains reduced. Only vitrification of oocytes matured in vivo yields foaling rates comparable to fresh oocytes. Recent advances in vitrification at the germinal vesicle (GV) stage, supported by systematic comparisons of cryoprotective agents and exposure times, has enabled consistent blastocyst production and birth of several foals. Comparative studies of GV and metaphase II (MII) stages suggest biological advantages of vitrification after in vitro maturation (IVM), warranting...
Embryo developmental kinetics and vitrification in relation to pregnancy outcome, foaling percentage and foal sex. While fast in vitro embryo development has been associated with improved outcomes, the relationships of slow in vitro embryo development and vitrified versus fresh in vitro produced (IVP) embryo transfer to foaling percentage and foal sex are less explored. Objective: To determine the relationships of (1) day of blastocyst formation (D7-11 after intracytoplasmic sperm injection (ICSI)) and (2) vitrification and warming method (one- and three-step) versus fresh transfer with pregnancy, early pregnancy loss (EPL), foaling percentage and foal sex. Methods: Retrospective clinical study. Methods: B...
Water and cryoprotectant permeability of mature equine oocytes: experimental measurements and in silico predictions. Vitrification of equine oocytes is an essential practice for advancing assisted reproductive technologies however, its efficiency remains limited due to the lack of stage and species-specific information on membrane permeability parameters. In this study, water (L) and CPA permeability (P) for dimethyl sulfoxide (Me₂SO) and ethylene glycol (EG) were measured in in vitro matured (MII) equine oocytes. Cumulus oocyte complexes were obtained from abattoir ovaries or by ovum pick-up and matured in vitro for 30 h at 6% CO. Oocytes followed ideal osmometer behavior principles, with an osmotically ...
Derivation of Equine Mesenchymal Stem/Stromal Cells from Induced Pluripotent Stem Cells via the Neural Crest Pathway and Characterisation by Immunophenotype and Tri-Lineage Differentiation. Mesenchymal stem/stromal cells (MSCs) hold promise for treating different equine conditions but enter senescence during culture. Using induced pluripotent stem cells (iPSCs) to derive MSC-like cells (iMSCs) can increase cell availability and diminish the need for invasive and repeated tissue harvesting. While human iMSCs are intensively studied, research on equine iMSCs (eqiMSCs) is very limited and has focused on strategies for spontaneous differentiation to obtain these cells. The aim of this study was to obtain MSC-like cells from equine iPSCs (eqiPSCs) by directing their differentiation vi...
Protective effects of adiponectin receptor agonists against equine lamellar endoplasmic reticulum stress. Lamellar endoplasmic reticulum (ER) stress occurs in hyperinsulinemia-associated and sepsis-related laminitis. Adiponectin is associated with reduced laminitis risk and inhibits ER stress in other species. Objective: To induce ER stress in ex vivo equine lamellar cells using pharmacological agents. To determine whether co-treatment with adiponectin receptor agonists (ARAs) reduces ER stress. Methods: In vitro. Methods: Lamellar cells from n = 4-5 horses were treated with tunicamycin or thapsigargin (10-1000 nM) for 2-24 h. ER-stressed cells were co-treated with full-length adiponectin ...
Comparison of cost for conventional embryo transfer versus intracytoplasmic sperm injection. There are obvious practical advantages of both conventional ET and ICSI. One question that has not been addressed adequately, however, is the relative cost of each procedure and if there is a cost advantage of one over the other. Objective: The objective of the present study was to obtain additional cost data from clinics and breeding farms that perform both ET and ICSI. Methods: A request was sent to 10 clinics that performed either just OPU or OPU/ICSI. These facilities were representative of reproductive specialists located all across the United States. Six clinics provided information on a...
Conventional IVF in the horse past, present, and future: physiological and technical insights. For decades, conventional in vitro fertilization (IVF) in the horse was ineffective, leading to reliance on intracytoplasmic sperm injection (ICSI) for both research and clinical in vitro embryo production. However, the ability to achieve IVF is essential to the study of key reproductive processes, including sperm capacitation, fertilization, and early embryonic development. Recently we have established a repeatable and efficient IVF system for horses, using long-term (9-22 h) sperm pre-incubation. For clinical use, IVF has many features that may support higher embryo quality than does ICSI, a...
Integrated workflow for production and in vitro characterization of equine anti-SARS-CoV-2 hyperimmune serum with epitope mapping. This study establishes an integrated workflow linking antibody production, neutralization assessment, and epitope mapping, supporting the identification of antigenic regions recognized by polyclonal antibodies generated in vivo. The viral suspension was inactivated with β-propiolactone under biosafety level 3 (BSL-3) conditions, with no cytopathic effect or plaque formation observed, confirming loss of viral replicative capacity. The produced immunogen retained antigenic activity, as demonstrated by reactivity with IgG antibodies from vaccinated and previously infected individuals. Protein an...
A novel flowable calcium silicate cement for endodontic therapy in equine teeth. Equine endodontic treatment for apical infections is performed infrequently due to anatomical and accessibility challenges of equine cheek teeth. However, the alternative of extraction is not without risk and lifelong implications for the horse. Mineral trioxide aggregate (MTA), a calcium silicate cement (CSC), has been used successfully in human dentistry for decades. MTA and other CSCs demonstrate excellent biocompatibility with favourable antimicrobial and physicochemical properties. These characteristics may support their application as an alternative filling material when used in equine e...
FGF2, LIF, and IGF1 supplementation during in vitro maturation or culture improves equine ICSI embryo development in an age-dependent manner. Ovum pickup (OPU) combined with intracytoplasmic sperm injection (ICSI) has reshaped equine assisted reproduction, enabling embryo production from mares and stallions with constrained breeding opportunities; however, limited efficiency of in vitro maturation (IVM) and in vitro culture (IVC) continues to hinder embryo production. Growth factor supplementation with fibroblast growth factor 2 (FGF2), leukemia inhibitory factor (LIF), and insulin-like growth factor 1 (IGF1) in combination (FLI) has been shown to enhance oocyte and embryo developmental competence in several species. Objective: This...
Comparison of in vitro degradation of immunoreactive adrenocorticotropic hormone and insulin in equine blood measured by two immunoassay methods. This study compared the in vitro stability of equine plasma adrenocorticotrophic hormone (ACTH) and serum insulin measured by chemiluminescent assay (CLA; Siemens Immulite 2000XPi) and immunofluorescent assay (IFA; Tosoh AIA-900) after storage at 4°C or room temperature (approximately 21°C) for clinically relevant periods. Fresh equine EDTA blood for ACTH and coagulated blood for insulin were aliquoted and analysed immediately (T0) and after storage. ACTH was assessed at 24, 48 and 72 hours; insulin was assessed at 24 hours, 72 hours and 7 days. Percentage recovery relative to T0 was analyse...
In vitro cultivation of Trypanosoma equiperdum: Comparison of in vitro and in vivo antigens for an ethical and sustainable serological diagnosis of Dourine. The protozoan Trypanosoma equiperdum is the causative agent of Dourine, a contagious sexually transmitted disease of equines that can manifest itself in chronic or acute form. Dourine has serious veterinary and economic implications, as there are no vaccines available for prevention and the management of the disease requires the culling of infected animals, together with rigorous sanitary control measures. This study compares the traditional production of T. equiperdum antigen grown in vivo, with an in vitro cultivation methodology developed to eliminate the use of animals. The in vitro and in...
Allogeneic Platelet-Rich Gel Supernatant Reprograms the Cytokine and Growth Factor Microenvironment in an Equine In Vitro Inflammatory Tendon System. Tendinopathy involves a dysregulated inflammatory microenvironment in which cytokines, growth factors (GF) and extracellular matrix components interact dynamically. Platelet-rich plasma (PRP) is widely used as a regenerative therapy, but its mechanisms of action in inflamed tendon remain unclear. This study evaluated whether platelet-rich gel supernatant (PRGS) reprograms the inflammatory-anabolic mediator network in an equine in vitro tendon explant system stimulated with lipopolysaccharide (LPS). Tendon explants were cultured under six experimental conditions, including non-stimulated contro...
Hyperactivation and Tyrosine Phosphorylation of Cryopreserved Stallion Spermatozoa in Relation to Conventional In Vitro Fertilization Blastocyst Production. Challenges in establishing clinical conventional in vitro fertilization (IVF) in horses include variation in sperm and oocyte quality, which can be affected by mare age. Extended preincubation of stallion spermatozoa has resulted in successful IVF. However, there is limited research on the impact of preincubation on sperm characteristics and IVF success. Objective: Responses of frozen-thawed stallion spermatozoa over time under IVF preincubation conditions were evaluated, and samples based on specific responses were tested for their ability to fertilize oocytes, including those from older mare...
Membrane and mitochondrial antioxidants improve post-thaw functional quality of stallion spermatozoa. Cryopreservation of stallion semen induces oxidative stress that compromises sperm motility, membrane integrity, and mitochondrial function. Given the high mitochondrial reliance of equine spermatozoa and their susceptibility to oxidative damage, compartment-specific antioxidant strategies may improve post-thaw functional resilience. This study evaluated the effects of astaxanthin, a membrane-active carotenoid, and MitoTEMPO, a mitochondria-targeted superoxide scavenger, on the functional and oxidative status of frozen-thawed stallion spermatozoa. Ejaculates from nine stallions were cryopreser...
An in vitro collagen gel contraction assay to assess the relaxing effect of potential pharmacological alternatives to oxytetracycline on foals’ tendons. Oxytetracycline has been successfully used to treat flexural limb deformities in foals. However, its antimicrobial properties and potential adverse side effects warrant the investigation of alternatives. Inhibition of matrix metalloproteinases (MMPs) or collagen cross-linking have been suggested as possible mechanisms of action. This study assessed the influence of potential alternative substances lacking antimicrobial properties on collagen gel contraction by juvenile equine myofibroblasts in vitro. Myofibroblasts were isolated from forelimb SDFTs and inferior check ligaments from foals eutha...
Equine Oocyte and Embryo Metabolism in the ART Setting: Current Knowledge and Clinical Significance. Equine in vitro embryo production has become very efficient and is used extensively worldwide for the clinical production of foals. What we know so far about offspring health and performance is promising; however, elements of the in vitro process remain unphysiological when compared to in vivo conditions. Studying the metabolism of oocytes and embryos can help inform the optimisation of culture systems and identify aberrations if they occur. Given the growing body of knowledge on the downstream effects of an inadequate peri-conception environment, both in vivo and in vitro, it is imperative th...
Holding immature equine oocytes for up to 3 nights prior to ICSI under practical shipping conditions (10-22 °C) is compatible with blastocyst development. In vitro embryo production via intracytoplasmic sperm injection (ICSI) is widely used in equine reproductive management. Shipping of immature oocytes allows oocyte recovery for ICSI to be performed by referring veterinarians. However, delays in oocyte shipment are common, and their effect on outcomes is unclear. Shipping is typically done at about 22 °C, but previous studies have shown that holding at 15 °C maintains equine oocyte developmental competence. We hypothesized that lower temperatures may better support oocyte viability if the case that delays occur. Oocytes (n = 664) were rec...
