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.
The Differences in Histoarchitecture of Hoof Lamellae between Obese and Lean Draft Horses. Obesity is a common problem in horses. The associations between obesity and equine metabolic syndrome (EMS) and between EMS and laminitis are known. However, there is a lack of data on whether obesity itself can affect hoof lamellae. Forelimbs and blood from 12 draft horses (six obese and six lean) from a slaughterhouse were acquired. To exclude laminitis and EMS horses, insulin concentration was measured, and hooves were radiographed. Histological evaluation was performed. The shape of the primary and secondary epidermal lamellae (PEL and SEL) was evaluated, and the length of the keratinized ...
The effect of repeated freezing and thawing on the suture pull-out strength in equine arytenoid and cricoid cartilages. To assess the effect of repeated freezing and thawing on the suture pull-out strength in arytenoid and cricoid cartilages subjected to the laryngoplasty (LP) procedure. Methods: Ex vivo experimental study. Methods: Ten grossly normal equine cadaveric larynges. Methods: Bilateral LP constructs were created using a standard LP technique. One hemilarynx was randomly allocated to the single freeze and thaw group and the other allocated to the repeated freeze and thaw (3 complete cycles) group. The suture ends of each LP construct were attached to a load frame and subjected to monotonic loading unt...
Luteal Tissue Area and Immunoreactive Concentration of Progesterone in Plasma of Bred and Non-bred Mares. Progesterone is pivotal to maintain pregnancy in the first trimester and low concentration ( .05). Multiple ovulations were associated with greater progesterone concentration and luteal tissue area (P = .0001). There was a moderate positive association between the number of ovulations and luteal tissue area (r = 0.54; P = .0001). The lack of change in the progesterone concentration and luteal tissue area between bred and non-bred mares suggests that horse seminal plasma does not affect luteal function in mares. As all mares had progesterone above 4 ng/mL after 5-days post-ovulation; it i...
DNA fragmentation of equine cumulus cells from Cumulus-Oocyte complexes submitted to vitrification and its relationship to the developmental competence of the oocyte. The objectives of this study were to evaluate the effect of vitrification on the DNA fragmentation rate of equine cumulus cells and to assess its relationship to oocyte in vitro maturation (IVM) after vitrification. Cumulus cells (CC) from 14 mares were recovered from COCs, previously submitted to vitrification (VIT) and IVM. The DNA fragmentation rate of the cumulus cells (CC-DF) was assessed using a chromatin dispersion test. CC-DF rates between vitrified and control COCs were statistically compared by Student's t-test. The rates of CC-DF from control COCs were lower than in vitrified COCs...
Training the equine respiratory muscles: Inspiratory muscle strength. Little is known about the response of the equine respiratory muscles to training. Objective: To measure an index of inspiratory muscle strength (IMSi) before and after a period of conventional exercise training (phase 1) and inspiratory muscle training (IMT), comparing high-load (treatment) and low-load (control) groups (phase 2). Methods: Prospective randomised controlled trial. Methods: Phase 1: Twenty National Hunt Thoroughbred racehorses performed an inspiratory muscle strength test (IMST) twice on two occasions; when unfit at timepoint A (July), and when race fit at timepoint B (October)....
Gut Fungal Microbiome Responses to Natural Cryptosporidium Infection in Horses. It is critical to characterize changes in the structure and composition of the host fungal community in natural infection, because it gives the possible overview of gut microbiome in host homeostasis and disease progression. A total of 168 rectal fecal samples were collected and examined using nPCR. The positive samples were double-checked using 18S rDNA high-throughput sequencing. After confirmation, ITS high-throughput sequencing was utilized to investigate the fungal community's response to natural infection. Results showed that a total of three positive samples (1.79%) were identified wi...
Association between forage mycotoxins and liver disease in horses. Outbreaks of liver disease in horses are common but the etiology of most remains unknown. Forage mycotoxins have been suspected to be a cause. Objective: To examine the association between outbreaks of liver disease and the presence of mycotoxins in forage stored on the same premises. Methods: Premises were identified where ≥4 horses were contemporaneously affected by liver disease, and a control group was formed from premises where ≥4 horses had been examined and found to have no evidence of liver disease. Methods: Forage was collected from 29 case and 12 control premises. The forage was ...
A 13-year retrospective study of equine abortions in Canada. The purpose of this study was to identify the most common causes of equine abortion in Canada, and to compare findings to similar reports from other countries. Equine. Necropsy reports from 901 equine abortion cases were acquired from provincial veterinary diagnostic laboratories across Canada. The final diagnosis was classified into basic abortion causes (infectious, non-infectious, unknown) and into primary and secondary categories for analysis. Non-infectious causes of abortion were the most frequently identified in Canada, with fetoplacental causes, including umbilical cord torsion or plac...
No Morphological Integration of Dorsal Profiles in the Araucanian Horse (Colombia). The aim of this research was to determine if the division between the cervical, dorsal, and croup profiles (three regions commonly assessed for descriptive profile purposes) has a modular basis as well as a morphological integration. For this, a total of 135 digital photographs were obtained, in a lateral view, of adult horses (14 females and 121 geldings; age range: 2-20 years), of the Araucanian breed, an equine population typical of the flooded savannah of Arauca, NE Colombia. From each image, 25 reference points (semi-landmarks) were obtained at the dorsal level of the neck, back, and crou...
Development and validation of a horse reference panel for genotype imputation. Genotype imputation is a cost-effective method to generate sequence-level genotypes for a large number of animals. Its application can improve the power of genomic studies, provided that the accuracy of imputation is sufficiently high. The purpose of this study was to develop an optimal strategy for genotype imputation from genotyping array data to sequence level in German warmblood horses, and to investigate the effect of different factors on the accuracy of imputation. Publicly available whole-genome sequence data from 317 horses of 46 breeds was used to conduct the analyses. Results: Depend...
Anatomical features for an adequate choice of the experimental animal model in biomedicine: III. Ferret, goat, sheep, and horse. The anatomical characteristics of each of the many species today employed in biomedical research are very important when selecting the correct animal model(s), especially for conducting translational research. In previous papers, these features have been considered for fish (D'Angelo et al., 2016), the most common laboratory rodents, rabbits, and pigs (Lossi et al. 2016). I here follow this line of discussion by dealing with the importance of proper knowledge of ferrets, goats, sheep, and horses' main anatomical features in translational research.
Osteochondrosis (Osteochondritis Dissecans) in Lusitano Horses: Prevalence and Characteristics. Osteochondrosis (osteochondritis dissecans), OC(D), is an important joint disorder that has been studied through the years in different breeds but, to our knowledge, there are no reports of its prevalence in Lusitano horses. The aim of this study was to assess the prevalence of OC(D) in Lusitanos, define the characteristics of the disorder in this breed and compare with Spanish Purebred horses. This is a retrospective study that analysed the radiographs from the metacarpometatarsophalangeal, tarsocrural and femoropatellar joints that were taken in 302 Lusitano horses (1-12 years; obtained from...
Survey of ocular abnormalities in draft horses. To determine the prevalence of ocular disease in draft horses in the United States. Methods: Draft horses of various breeds and ages. Methods: Nondilated ophthalmic examination was performed using slit lamp biomicroscopy and indirect ophthalmoscopy. Intraocular pressures were measured when possible. Results: One hundred sixty-five draft horses were examined. Age range: 10 days to 33 years (mean 10.8 years, median 10 years); 87 geldings (52.7%), 71 mares (43.0%), 7 stallions (4.2%); 64 Percherons (38.8%), 51 Belgians (30.9%), 29 Clydesdales (17.6%), 15 Shires (9%), and 6 other draft bre...
Is each horse unique and unrepeatable? An explanation through morphometric and statistical analysis of the limb bones. Horses went through functional differentiation during their evolutionary and reproductive development, however, some body parts continued to improve their specificity for speed. Regarding this, we evaluated by morphometric analysis the relationship between limb section (LS) differences in the appendicular structures of horses. Two hundred and seven (n = 207) adult horses of different breeds and sex were selected. The limb section was measured by identification of topographic palpable skeleton landmarks with a measurement tape (centimetres). Quantitative variables (limb section) were analysed...
Serum Phosphorylated Neurofilament Heavy Subunit Levels and its Association with the Risk for Catastrophic Injury in Thoroughbred Racehorses. Neurofilaments are structural proteins that are concentrated in the body and axons of neurons. Damage to the neurons or axons as a result of trauma or infectious diseases leads to the release of neurofilaments into blood and cerebrospinal fluid (CSF). This case-control study was carried out to compare serum levels of phosphorylated neurofilament heavy chain (pNF-H) between clinically healthy Thoroughbred (TB) horses and TB horses that suffered catastrophic musculoskeletal injuries (cMSI), and to investigate the correlation between putative risk factors and serum concentrations of pNF-H in inju...
Contrasting Volatilomes of Livestock Dung Drive Preference of the Dung Beetle Bubas bison (Coleoptera: Scarabaeidae). Volatile cues can play a significant role in the location and discrimination of food resources by insects. Dung beetles have been reported to discriminate among dung types produced by different species, thereby exhibiting behavioral preferences. However, the role of volatile organic compounds (VOCs) in dung localization and preference remains largely unexplored in dung beetles. Here we performed several studies: firstly, cage olfactometer bioassays were performed to evaluate the behavioral responses of (Coleoptera: Scarabaeidae) to VOCs emanating from fresh horse, sheep, and cattle dung; seco...
The impulsive horse: Comparing genetic, physiological and behavioral indicators to those of human addiction. Stress and genotype elicit changes in impulse control in a range of species that are attributable to adaptations in both the central and peripheral nervous system. We examined aspects of this mechanism in the horse by assessing the effect of a dopamine receptor genotype (DRD4) and central dopaminergic tone (measured via spontaneous blink rate [SBR] and behavioral initiation rate [BIR]), on measures of impulsivity, compulsivity (3-choice serial reaction time task) and sympathetic/ parasympathetic system balance (heart rate variability [HRV]). Genotype did not have a significant effect on any of...
Follicular-fluid proteomics during equine follicle development. The complex composition of the follicular fluid (FF), the intimate proximity to the oocyte, and the continual changes in their composition have a major effect on folliculogenesis and oogenesis. To date, the profiling of FF proteomes during follicle selection, development, and ovulation has not been comprehensively investigated. Therefore, a shotgun proteomics approach and bioinformatics analyses were used to profile the proteomes of equine FF harvested in vivo from follicles at the following development stages: predeviation (18-20 mm), deviation (22-25 mm), postdeviation (26-29 mm), preo...
Site- and Zone-Dependent Changes in Proteoglycan Content and Biomechanical Properties of Bluntly and Sharply Grooved Equine Articular Cartilage. In this study, we mapped and quantified changes of proteoglycan (PG) content and biomechanical properties in articular cartilage in which either blunt or sharp grooves had been made, both close to the groove and more remote of it, and at the opposing joint surface (kissing site) in equine carpal joints. In nine adult Shetland ponies, standardized blunt and sharp grooves were surgically made in the radiocarpal and middle carpal joints of a randomly chosen front limb. The contralateral control limb was sham-operated. At 39 weeks after surgery, ponies were euthanized. In 10 regions of interest (...
Pulmonary Function and Aerobic Capacity Responses to Equine Assisted Therapy in Adolescents with Idiopathic Scoliosis: A Randomized Controlled Trial. Idiopathic scoliosis is a common spinal malalignment that negatively impacts the respiratory system and physical conditioning in adolescents. Equine-assisted therapy comprises therapeutic horseback riding that optimizes physical performance and mobility in a range of contexts. However, the influence of equine-assisted therapy on pulmonary function remains unclear. Objective: To examine the impact of 10 weeks of hippotherapy combined with Schroth exercises on pulmonary function and aerobic capacity in adolescents with idiopathic scoliosis. Methods: A randomized controlled trial including 45 pat...
Influence of Chronic Lameness on Thoracolumbar Musculus Multifidus Structure in the Horse. The clinical relationship between equine limb lameness and secondary back dysfunction is largely unknown. Proper function of the spine is critical to maintain the integrity of the kinetic chain and attenuate forces from the appendicular skeleton. The musculus multifidus (m. multifidus) is the primary muscle providing spinal intersegmental stabilization and a functional relationship between m. multifidus hypertrophy and equine postural stability has been established. The relationship between equine thoracolumbar m. multifidus cross-sectional area (CSA) and limb lameness is unknown. The objectiv...
Differential Protein Expression of the Marginal Transitional Zone in Foals with Osteochondrosis. The marginal transitional zone is peripherally located within the diarthrodial joint, and represents the interface of articular cartilage, periosteum, and the fibrous joint capsule. The purpose of this study is to characterize the protein expression of matrix and molecular regulators in the marginal transitional zone of foals having osteochondrosis (OC) compared to normal foals. Several families of proteins with known roles in cartilage and bone development are investigated, including matrix molecules, Wnt signaling, apoptotic factors and paracrine cell signaling molecules. Our results demonst...
Lacrimal Secretion Variation and Menace Response Appearance in Healthy Standardbred Foals From Birth to Four Weeks of Age. This study assesses lacrimal secretion in healthy foals within 48 hours after birth and evaluates their variations in lacrimal secretion and menace response appearance during the first month of life. A total of 31 Standardbred foals were evaluated. Foals were housed with their dams in 4 × 4 m boxes throughout the study. A complete ophthalmic examination was performed for each animal enrolled in the study, including the foals' dams which were used as a control group to compare the lacrimal secretion of foals at birth with that of adult horses. In foals, the Schirmer Tear Test I (STT I) and m...
Tracking the Impact of Weather on Equine Activity While Pastured. Keeping horses outdoors on pasture full-time with free access to shelter holds numerous advantages over housing in stalls, promoting both better mental and physical health. One reason for these benefits is the potential for increased physical activity in horses outdoors on pasture versus those confined to stalls. However, it is not guaranteed the horse will take advantage of this opportunity for greater movement. For this reason, it is important to understand the various reasons why horse activity patterns change. The objective of this study was to investigate how various weather factors - inc...
Fecal microbiome of horses transitioning between warm-season and cool-season grass pasture within integrated rotational grazing systems. Diet is a key driver of equine hindgut microbial community structure and composition. The aim of this study was to characterize shifts in the fecal microbiota of grazing horses during transitions between forage types within integrated warm- (WSG) and cool-season grass (CSG) rotational grazing systems (IRS). Eight mares were randomly assigned to two IRS containing mixed cool-season grass and one of two warm-season grasses: bermudagrass [Cynodon dactylon (L.) Pers.] or crabgrass [Digitaria sanguinalis (L.) Scop.]. Fecal samples were collected during transitions from CSG to WSG pasture sections (...
Cultured dissociated primary dorsal root ganglion neurons from adult horses enable study of axonal transport. Neurological disorders are prevalent in horses, but their study is challenging due to anatomic constraints and the large body size; very few host-specific in vitro models have been established to study these types of diseases, particularly from adult donor tissue. Here we report the generation of primary neuronal dorsal root ganglia (DRG) cultures from adult horses: the mixed, dissociated cultures, containing neurons and glial cells, remained viable for at least 90 days. Similar to DRG neurons in vivo, cultured neurons varied in size, and they developed long neurites. The mitochondrial movem...
Early castration in foals: Consequences on physical and behavioural development. The impact of very early castration of foals has not yet been studied despite the many positive effects observed in dogs and cats. Objective: The objective of the study was to compare castration at 3 days and 18 months and assess their subsequent morphological and behavioural development. Methods: This was a randomised, blinded clinical study. Methods: Twenty-two Welsh ponies underwent either early (3-day old, EC group, n = 11) or traditional (18-month old, TC group, n = 11) castration. Animals were followed up to 3 years of age. All ponies were castrated using a primary closure techn...
Training the equine respiratory muscles: Ultrasonographic measurement of muscle size. Limited information exists regarding changes in the size of respiratory and locomotor muscles in response to exercise training in the Thoroughbred racehorse. Objective: To describe and compare the responses of the respiratory and locomotor muscles to conventional exercise training and inspiratory muscle training (IMT). Methods: Prospective randomised controlled trial. Methods: Thoroughbred racehorses, in training for competition in National Hunt races, were recruited from two training establishments. Ultrasonographic images were obtained for selected muscles of the upper airway, diaphragm, acc...
The Gut Microbiome of 54 Mammalian Species. The gut microbiome plays a critical role in many aspects of host life, and the microbial community composition is heavily influenced by the prevailing conditions in the gut environment. Community composition has been suggested to have large implications for conservation efforts, and gut health has become of interest for optimizing animal care in captivity. In this study, we explore the gut microbiome of a wide range of animals in the context of conservation biology. The composition of the gut microbial community of 54 mammalian animal species was investigated using 16S rRNA gene amplicon seque...