Topic:Comparative Study
Comparative studies in equine research involve the systematic analysis of different horse breeds, management practices, or physiological responses to identify variations and similarities. These studies are instrumental in understanding how different factors influence health, performance, and behavior in horses. Common areas of comparison include genetic traits, nutritional requirements, disease resistance, and response to training. By evaluating these differences, researchers can develop targeted strategies for breeding, healthcare, and training. This page aggregates peer-reviewed research studies and scholarly articles that focus on the methodologies, findings, and implications of comparative studies in the context of equine science.
Comparative Evaluation of Sperm Quality Assessment Methods in Purebred Spanish Horses. Evaluating semen quality in Purebred Spanish Horses is essential to determine reproductive potential and optimize assisted reproductive techniques. Objective: This study compared several sperm analysis methods in Purebred Spanish Horses to standardize protocols suitable for both laboratory and field conditions. Methods: Fifteen stallions were evaluated through three ejaculates, analyzing sperm parameters using different techniques. Sperm kinematics was assessed by Sperm Computer Analyzer (SCA-CASA) or iSperm mCASA. Viability was analyzed by eosin-nigrosin-Giemsa (ENG) staining or Hoechst 33258...
A topographic analysis of skin thickness in horses. A systematic study of regional skin thickness in different types of horses has not yet been described. Knowledge about regional skin thickness has long been used in human medicine to optimise wound care and skin grafting outcomes and similar knowledge could prove useful in equine wound management. The objective of the current study was to report the topographical variation in skin thickness of Warmblood (WB) and Coldblood (CB) type horses and to compare different methods for measuring skin thickness. Horses free of skin conditions and euthanised for reasons unrelated to this study were include...
Updates on Seizures and Epilepsy in the Horse. The goal of this article is to provide the equine practitioners with a framework for a diagnostic algorithm for the patient presented with possible seizures/epilepsy. Using a comparative approach, a review of companion animal and human research is provided with the intention of expanding our current knowledge on seizure/epilepsy, as well as diagnostic and treatment strategies for equine patients.
Comparative Evaluation of Follicular Flushing Frequency and Scraping Time During Ovum Pick-Up in Mares: Effects on Oocyte Recovery Rate and Technical Considerations. Transvaginal ultrasound-guided follicular aspiration or ovum pick-up (OPU) has become the standard technique for oocyte collection in mares for intracytoplasmic sperm injection (ICSI). Although repeated follicular flushes and wall scraping are commonly used to improve oocyte recovery rate (ORR), the relative contribution of each remains unclear. This study aimed to compare the effects of multiple flushes versus controlled scraping time on ORR in mares. A controlled trial was conducted in two phases: (1) an ex vivo phase using slaughterhouse ovaries (n = 32), and (2) an in vivo phase in c...
Engineered biopolymeric hydrogels for in vitro modeling of equine sarcoid tumors in comparative oncology. Developing advanced preclinical in vitro cancer models is essential for understanding tumor biology, improving drug discovery, and enhancing the clinical translation of new therapies. Papillomaviruses (PVs) cause diverse lesions in humans and animals; notably, bovine papillomavirus (BPV) is the main cause of equine sarcoid, the most common skin tumor in horses. Its pathogenesis involves viral infection, fibroblast transformation, and extracellular matrix (ECM) remodeling. These processes highlight the limitations of conventional two-dimensional (2D) culture systems, which fail to replicate the...
Single-cell atlas of the equine placenta reveals cellular heterogeneity and gestational-stage-associated programs. The placenta mediates critical interactions between mother and offspring that guide development and impact long-term health. Despite its importance, the cellular organization of the equine (Equus caballus) placenta remains poorly defined. The equine epitheliochorial placenta, characterized by the absence of trophoblast invasion and prominent endocrine activity, provides a unique comparative model for studying placental cellular composition and development. Methods: We applied single-cell RNA sequencing to chorioallantois tissue collected from first-trimester (n = 1) and term (n = 2) equine...
Cross-Species Analysis of Transcriptomic Response to Alpha-Herpesvirus Infection in Human, Bovine and Equine Cells. Comparative transcriptomics offers a powerful approach to elucidate host-virus interactions across related pathogens, yet systematic evaluations across species-matched cellular systems remain limited. We performed a cross-species RNA sequencing analysis of respective species' cells infected with three alphaherpesviruses-herpes simplex virus 1 (HSV-1), bovine alphaherpesvirus 1 (BHV-1), and equid alphaherpesvirus 1 (EHV-1)-to dissect conserved and virus-specific transcriptional responses. We show that certain orthologous genes and orthologous pathways are differentially regulated upon infection...
Genome-Wide DNA Methylation Analysis of Performance Variation in the 5000-m Speed Race of Yili Horses. Whole-genome bisulfite sequencing (WGBS) was employed in this article to map blood DNA methylation profiles at single-base resolution in Yili horses before a 5000 m speed race, with comparative analysis of epigenetic differences between the 'elite group' and 'ordinary group' across six four-year-old stallions. The overall methylation level in the elite group was generally higher than that in the ordinary groups, with a minority of regions showing hypomethylation. For instance, the promoter regions of key metabolic and neuro-related genes exhibited significant hypomethylation. The article ident...
Comparative Analysis of Extracellular Vesicle Isolation From Equine Serum and Plasma Using Two Isolation Methods With Structural and Proteomic Validation. Extracellular vesicles (EVs) are promising biomarkers and mediators of intercellular communication, but their isolation from equine biofluids remains challenging. This study compared two isolation workflows-size-exclusion chromatography (SEC) and differential ultracentrifugation followed by SEC (UC + SEC)-to evaluate their efficiency, reproducibility, and the proteomic composition of EVs derived from equine serum and plasma. Blood from six healthy horses was processed to obtain platelet-free plasma and serum. EVs were isolated using SEC or UC + SEC and characterized by transmission ele...
Validation of a handheld smartphone markerless gait-analysis tool using an estimated groundline in horses. A handheld smartphone-based computer vision algorithm (RealHorse® [RH]) offers accessible alternatives for equine gait analysis but requires validation against a gold-standard three-dimensional multicamera optical motion capture system (Qualisys® [QS]). Objective: To evaluate the accuracy and precision of RH in measuring vertical displacement signals (VDS) at the eye, withers, back and croup in horses trotting on a straight line and on a circle. Methods: Cross-sectional comparative validation study of a markerless computer vision algorithm. Methods: Fifty-nine horses were recorded while trot...
Comparative tensile properties of the equine vagina, penile sheath, and scrotum. This experimental study characterizes the elastic behavior of male and female equine genital tissues using uniaxial tensile testing, with strain measurements obtained via digital image correlation. Dog-bone-shaped tissue specimens were excised from mares and geldings (n=23 from female specimens and n=42 from male specimens) with all specimens aligned along the circumferential direction (CD) of the vagina, penis, and scrotum. The results include load-displacement data, stress-strain data, and tangent moduli for the penile sheath, vaginal canal, and scrotum, with strain measured in both the CD a...
Comparative analysis of the organization and complexity of immunoglobulin light chain loci in equids. This study investigated three donkey breeds-Guanzhong, Jiami, and Northern Shaanxi-to characterize the structural organization and diversification mechanisms of the immunoglobulin light-chain (IgL) loci and to conduct both intra-breed and interspecies comparisons with horses. The donkey IGλ locus is located on chromosome 8 and arranged in a Vλ-(Jλ-Cλ)-Vλ configuration. It contains 7 Cλ genes, each preceded by a corresponding Jλ gene to form a Jλ-Cλ cluster. Upstream of this cluster, 156 Vλ genes were identified, including 29 potential functional genes; downstream, 98 Vλ genes were d...
Evaluating the Accuracy of a Vision-Based Algorithm for Groundline Estimation in Trotting Horses Using Multiple Camera Angles. Equine lameness diagnosis largely relies on subjective visual assessments, which can be biased. Although marker-based methods, force plates and inertial measurement units (IMUs) provide objective measurements, they require specialized setups. Vision-based algorithms offer a portable, markerless alternative, but their accuracy needs thorough testing. Objective: To evaluate a custom vision-based algorithm for estimating the groundline across multiple camera angles, including handheld use in horses trotting on a treadmill. Methods: Experimental comparative study. Methods: Eight Standardbred trott...
Comparing isoflurane and desflurane: A prospective randomised blinded clinical trial in horses undergoing elective surgery. The recovery period is associated with the greatest risk of injury for horses undergoing anaesthesia. Recovery quality and duration can be influenced by the volatile agent. Methods: This prospective, randomised blinded clinical investigation recruited 101 healthy client-owned horses undergoing elective surgery at one UK equine hospital. Anaesthesia was standardised, and horses were randomly assigned to receive desflurane or isoflurane for maintenance. Horses were ventilated to normocapnia and received dobutamine to maintain mean arterial blood pressure above 60 mmHg. All the patients received ...
Comparison of body temperatures and pulse rate between athletic and non-athletic horses during the hot-humid condition. Clinical assessment of parameters that give indications of the health status and fitness of horses are very important in equine practice. The study aimed to compare the resting body temperatures at different anatomical sites and resting pulse rates of athletic and non-athletic horses. Eighteen horses were used for the study, comprising ten athletic and eight non-athletic horses. Measurements of environmental parameters, rectal temperature (RT), body surface temperature (BST) and pulse rate were recorded between 9 and 11 am twice with one week interval at the Ibadan Polo Club, Eleyele, Ibadan, ...
Mitochondrial genome assembly of the Peruvian Paso horse through PacBio long-read sequencing. The complete mitochondrial genome of the Peruvian Paso Horse was assembled using PacBio HiFi long reads, resulting in a high-quality circular genome of 16,617 bp comprising 13 protein-coding genes, 22 tRNAs, 2 rRNAs, and a control region. Nucleotide composition and gene structure were consistent with other equine mitogenomes. Codon usage analysis revealed a bias toward CUA (Leu), AUA and AUC (Ile), suggesting translational optimization. Thirty-five heteroplasmic variants were identified, predominantly located in RNA genes (12 S rRNA and tRNA-Phe), with allele frequencies between 0.10 and 0.6...
Differential Energy Metabolism in Skeletal Muscle Tissues of Yili Horses Based on Targeted Metabolomics and Transcriptomics Analysis. Skeletal muscle is the largest organ system in mammals. To investigate the differences in energy metabolism across various skeletal muscles in Yili horses, this study examined muscle fiber type distributions through immunohistochemical staining of muscles, including the splenius, triceps brachii, longissimus dorsi, and gluteus medius. The splenius and gluteus medius muscles, which exhibited the greatest differences in the proportion of slow-twitch fiber area, were selected for further comparison of differential metabolites and transcriptomic expression profiles between slow-twitch and fast-twi...
Comparison between SNP array and imputed data to estimate population structure and ROH hotspots in horse breeds. Single nucleotide polymorphism (SNP) arrays are commonly used for studying the genomic structure and diversity of livestock breeds, but whole-genome sequencing (WGS) provides higher-resolution genomic data. Genotype imputation has become a standard practice for increasing the genomic resolution of association studies. This work aimed to extend imputation to biodiversity analyses, comparing SNP array data before and after imputation. A 40 k SNP dataset of 281 horses from 12 breeds (DS) was imputed to sequence-level using a reference panel of 327 sequenced individuals, generating approximately 9...
Naloxone supplementation during vitrification of equine in vitro matured oocytes after overnight holding: insights from a comparative study with the bovine model. Cryopreservation of equine mature oocytes remains a major challenge in assisted reproduction, mainly due to the limited availability of material and logistical constraints requiring a holding phase. To address these issues, this study evaluated whether naloxone (NX), an opioid receptor antagonist with reported antioxidant properties, could improve vitrification outcomes and whether bovine oocytes could serve as a suitable preliminary and supportive model. Two experiments were conducted. In experiment 1, immature (bGV) and mature (bMII) bovine oocytes were vitrified without (VIT) or with NX (VI...
A SLC45A2 mutation is strongly associated with the cream dilution in Baroque donkeys. Domestic Baroque donkeys are popular animals in many European parks and zoos. Although their cream coat color is very charismatic, the underlying genetics is still undiscovered. Addressing this question, a candidate approach was used to search for the causative mutation.Considering the knowledge from domestic horses, the () was identified as the most promising candidate. Samples from 77 domesticated donkeys, 11 wild equids, 1 mule and 2 domestic horses were included in comparison. All exons and the flanking intron sequences of the were sequenced (2774bp).Sequence comparison revealed that a m...
A systematic review on the effect of individual characteristics and management practices on equine cognition. Equine cognition is relevant to the many roles that horses serve in society, such as leisure riding, competitions, or even animal-assisted therapy. Equine cognitive abilities have been explored in recent years. However, gaining an overview of horse cognition is challenging due to the broad range of abilities studied and the diverse methodologies employed. In addition, the subjects of existing equine cognition studies vary greatly in contextual factors such as their breed, age, sex, and management conditions - each of which may influence test performance in the following cognitive categories: D...
Comparative Analysis of the Stallion Field Performance Test at Different Training Stages and Horse Age. Breeding value estimations of Warmblood horses in Poland are based on field performance, but the amount of stallions' data is still insufficient (334 horses). The first study's aim is to compare stallions' results in different stages and evaluate the overall ability using both stages. The effects on preselection (first stage free movement) and performance tests (second stage under rider) were analyzed separately and together as the overall ability. Spearman correlations were evaluated. The second aim was to evaluate the training period on the results. Due to the pandemic and lack of tests, hor...
Transcriptomic profiling reveals similarities between equine IVF and ICSI embryos. In vitro production of equine embryos has been performed using intracytoplasmic sperm injection (ICSI) for the last two decades. Since 2022, a repeatable protocol for conventional in vitro fertilization (IVF) provides a successful alternative. However, little is known about the influence of the fertilization method on embryo quality and the transcriptomic profile. In this study, we aimed to examine differentially expressed genes (DEGs) between ICSI and IVF embryos in the horse. Therefore, ten equine sibling blastocysts, produced in vitro by either ICSI or IVF from three different mares, were s...
Reliability, agreement and variability of a markerless computer vision algorithm for equine gait analysis under field conditions. Computer vision-based algorithms offer accessible alternatives for equine gait analysis but require thorough assessment under diverse conditions. Objective: To evaluate a proprietary vision-based algorithm's reliability in measuring vertical displacement signals (VDS) at the eye, withers and croup, alongside groundline estimation, for horses trotting on straight lines and circles under field conditions. Methods: Cross-sectional comparative study evaluating agreement, variability and reliability of a markerless computer vision algorithm. Methods: We obtained 67 handheld iPhone recordings from 3...
Cellular interactions and gene expression analysis of two equine-derived bone graft materials: an in vitro study. Bone grafting is a surgical procedure that involves the use of bone tissue or bone substitutes to repair damaged bone. In dentistry and maxillofacial surgery, bone graft substitutes from various sources are commonly used. Given their critical role in clinical outcomes, it is essential to thoroughly investigate the biological and mechanical properties of these materials. Methods: In this in vitro study, we evaluated the biological properties of two equine-derived bone graft substitutes in comparison to β-tricalcium phosphate. The materials included one equine-derived graft containing hydrolyze...
Ultrasound-guided versus blind intercostal nerve injection in equine cadavers. To describe the detailed anatomy of the equine thoracoabdominal region and to compare the accuracy of ultrasound-guided versus blind intercostal nerve injection techniques, targeting the thoracic intercostal nerves (T12-T18) in equine cadavers. Methods: Randomized, blinded, cadaveric study. Methods: Eight fresh adult equine cadavers. Methods: Eight horse cadavers were used: one in phase I (436 kg; 4 years old) for anatomic landmarks identification and seven in phase II [420 (317-560 kg); 16 (3-22 years old) [median (minimum-maximum)] for comparative study. In phase I, dissections were performe...
Intraocular Tumors in Horses: Diagnosis, Tumor Classification, Oncologic Assessment and Therapy. Intraocular neoplasia in horses is rare and only few case reports and small case series exist. Intraocular neoplasia has various clinical signs and includes important differential diagnoses in ocular disease. This narrative review of the current literature aims to provide a clinically relevant overview and classification of intraocular tumors in horses and adds a comparative oncological perspective concerning diagnosis, treatment and future considerations. The available clinical and imaging examination techniques allow for a reliable and differentiated investigation of the tumor, even in the s...
Lectin Microarray-based Glycomics and Machine Learning Identify Shared Osteoarthritis Biomarkers in Humans, Dogs, and Horses. Post-traumatic osteoarthritis (PTOA) is a common sequela to joint injury in both humans and companion animal species such as horses and dogs. Despite the increasing prevalence of osteoarthritis (OA) in humans, investigation of glycosylation changes associated with OA remains in its infancy. Recent advances, such as lectin microarray analysis, now enable detailed glycan profiling in complex biofluids such as synovial fluid. Using lectin microarray technology, this study characterized glycosylation patterns in synovial fluid samples from healthy and OA-affected joints in horses, dogs, and humans...
What if Horses Were Humans? Comparing Rein Tension and Bit Pressures to Human Pressure Pain Thresholds. Bit pressure and rein tension-induced mouth pain in horses have recently become a significant welfare concern, fueling debates within the equestrian community and beyond. Evidence indicates that bits can cause pain-related behaviors and even oral lesions. Although studying pressure-induced pain in animals is challenging, the similarities in the physiology of pain processing (nociception) across mammals suggest that it is reasonable to assume that pain perception in humans and horses is principally comparable. Therefore, we compared human pressure pain detection thresholds (PPDTs) to reported r...
Comparative analysis of 3 qPCR primer-probe sets for the detection of equid alphaherpesvirus 1. With the revision of the World Organisation for Animal Health (WOAH) Terrestrial Manual on equine rhinopneumonitis in 2024, 3 recommended qPCR primer-probe sets were added for the detection of equid alphaherpesvirus 1 (EqAHV1; formerly equine herpesvirus 1 [EHV1]; family , taxon species ), also known as equine abortion virus. We compared the sensitivity and specificity of the 3 qPCR primer-probe sets to determine the most reliable set. Sets gB1H and gB1P, which target the glycoprotein B () gene of EqAHV1, detected all 10 copies and even lower copy numbers. In contrast, set gC1 (ISO 17025-accre...