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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.
Growth rate of ovulatory follicles during the first ovulatory oestrus (after seasonal anoestrus) and subsequent oestrous period in Irish Draught mares. It is believed that during the spring transition, the developing follicle tends to grow more slowly, persist longer and grow to a larger diameter prior to ovulation than at subsequent oestrus periods. A general suspicion, that the first ovulation of the year is less fertile than subsequent ovulations could be explained by a slower growth rate of the ovulatory follicle during transition with the consequent production of a subfertile oocyte. By detailed serial examination of the same group of Irish Draught mares over three winter/spring periods, no significant difference was found in either grow...
Comparison of microbial populations in the small intestine, large intestine and feces of healthy horses using terminal restriction fragment length polymorphism. The composition of the microbiota of the equine intestinal tract is complex. Determining whether the microbial composition of fecal samples is representative of proximal compartments of the digestive tract could greatly simplify future studies. The objectives of this study were to compare the microbial populations of the duodenum, ileum, cecum, colon and rectum (feces) within and between healthy horses, and to determine whether rectal (fecal) samples are representative of proximal segments of the gastrointestinal tract. Intestinal samples were collected from ten euthanized horses. 16S rRNA gen...
Pharmacokinetics and pharmacodynamics of d-chlorpheniramine following intravenous and oral administration in healthy Thoroughbred horses. The pharmacokinetics of d-chlorpheniramine (CPM), a histamine H1-receptor antagonist, and its ability to inhibit of histamine-induced cutaneous wheal formation, were studied in healthy Thoroughbred horses (n=5). Following an intravenous (IV) dose of 0.5mg/kg bodyweight (BW), plasma drug disposition was very rapid, with the mean terminal half-life and total body clearance calculated as 2.7h and 0.7 L/h/kg, respectively. The observed maximal inhibition of wheal formation following IV doses of 0.1 and 0.5mg/kg BW were 37.8% and 60.6% at 0.5h, respectively. Oral administration of CPM (0.5mg/kg BW)...
The effects of hyperglycemia and endotoxemia on coagulation parameters in healthy adult horses. Hyperglycemia and endotoxemia have been associated with coagulation abnormalities in horses. Studies in humans suggest greater disturbances in coagulation with hyperglycemia and concurrent endotoxemia. Objective: To compare coagulation parameters in horses administered with lipopolysaccharide (LPS) with and without concurrent hyperglycemia. Methods: Twelve healthy adult horses. Methods: Hyperglycemia (180-240 mg/dL) was maintained for 6 hours in 6 horses (GLU-LPS) using 140 mg/kg IV bolus of dextrose followed by a 20% dextrose constant rate infusion. A similar volume of saline was administe...
Lessons of history in veterinary medicine. The future of veterinary medicine is best understood in the context of history. What began as a profession rooted in urban centers in proximity to horses, physicians, and medical schools, was transformed into a land grant-based agricultural profession with the arrival of the internal combustion engine in the early twentieth century. Most of the United States' current veterinary colleges are still located in towns or small cities in the middle section of the country, outside the largest metropolitan areas where most veterinarians practice companion-animal medicine. Throughout veterinarian histo...
Pharmacokinetics of a peroral single dose of two long-acting formulations and an aqueous formulation of doxycycline hyclate in horses. Doxycyline (Dox) is a semisynthetic antibacterial drug with pharmacological advantages over its parent drug (tetracycline) in the treatment of various bacterial diseases in horses. Yet, at present a horse-customized pharmaceutical formulation is not available. Based on its pharmacokinetic/pharmacodynamic (PK/PD) ratio, Dox is considered a time-dependent antibacterial drug and ideally expected to achieve sustained plasma drug concentrations both at or slightly above the minimal inhibitory concentration (MIC) level for as long as possible between dosing intervals. Hence, the objective of this st...
Harnessing the power of personality assessment: subjective assessment predicts behaviour in horses. Objective assessment of animal personality is typically time consuming, requiring the repeated measure of behavioural responses. By contrast, subjective assessment of personality allows information to be collected quickly by experienced caregivers. However, subjective assessment must predict behaviour to be valid. Comparisons of subjective assessments and behaviour have been made but often with methodological weaknesses and thus, limited success. Here we test the validity of a subjective assessment against a battery of behaviour tests in 146 horses (Equus caballus). Our first aim was to determ...
The nasal vestibulum is the optimal sampling site for MRSA screening in hospitalised horses. The increased incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection in equine hospitals highlights the need for infection control protocols based on optimal patient screening. In horses, the deep ventral meatus of the nasal cavity is the principal site sampled to detect MRSA. However, in humans, the anterior nares are the preferred sampling site. The objective of this study was to determine the optimal sampling location in the nasal chambers for MRSA in horses by comparing the results obtained from three different locations (the vestibulum, diverticulum and ventral meatus) ...
Morphometric analyses of the body and the branches of the normal third interosseous muscle (suspensory ligament) in Standardbreds. The third interosseous muscle (suspensory ligament, TIOM) is composed of connective tissue (CT) with a variable proportion of muscle (MT) and adipose tissue (AT). The aim of our study is to quantify the CT, MT and AT within the body and the branches of right thoracic and pelvic limbs TIOM in sound horses to determine whether there are differences in CT, MT and AT between age, sex, limbs and levels. Right limbs from 11 sound horses were collected. Samples from 6 levels of the TIOM were embedded in paraffin or in Tissue-Tek(®) . Most of the paraffin sections were shredded. Using the cryosection...
Differentiation and activation of equine monocyte-derived dendritic cells are not correlated with CD206 or CD83 expression. Dendritic cells (DC) are the main immune mediators inducing primary immune responses. DC generated from monocytes (MoDC) are a model system to study the biology of DC in vitro, as they represent inflammatory DC in vivo. Previous studies on the generation of MoDC in horses indicated that there was no distinct difference between immature and mature DC and that the expression profile was distinctly different from humans, where CD206 is expressed on immature MoDC whereas CD83 is expressed on mature MoDC. Here we describe the kinetics of equine MoDC differentiation and activation, analysing both ph...
Measures of antioxidant status of the horse in response to selenium depletion and repletion. Selenium plays a role in the antioxidant mechanism via the selenoenzyme glutathione peroxidase (GSH-Px). Change in Se status because of Se depletion or supplementation is associated with a change in GSH-Px activity and could potentially affect antioxidant status. This study evaluated the impact of change in Se status on measures of antioxidant status and oxidative stress in adult horses. Twenty-eight horses were blocked by age and gender and were randomly allocated to 1 of 4 dietary treatment groups: low Se (LS), adequate Se (AS), high organic Se (SP), and high inorganic Se (SS). For 196 d, LS...
Digestive capacity in weanling and mature horses. The ability of young and mature horses to digest DM, OM, and NDF was compared using 6 weanling colts and 6 mature (13.2 ± 3.0 yr) geldings. Each colt was paired with a gelding, and the pair was adapted to a diet containing 67% alfalfa cubes and 33% concentrate for 21 d. During the adaptation period, horses were accustomed to housing and all handling procedures. The adaptation period was also used to adjust the amount of feed offered to minimize orts and to maintain similar rates of intake within a pair. After the adaptation period, a 5-d fecal collection period using fecal collection harnesse...
Proteomic comparison of equine and bovine milks on renneting. Rennet-induced coagulation of bovine milk is a complex mechanism in which chymosin specifically hydrolyzes κ-casein, the protein responsible for the stability of the casein micelle. In equine milk, this mechanism is still unclear, and the protein targets of chymosin are unknown. To reveal the proteins involved, the rennetability of equine milk by calf chymosin was examined using gel-free and gel-based proteomic analysis and compared to bovine milk. RP-HPLC analysis of bovine and equine milks showed the release of several peptides following chymosin incubation. The hydrolyses of equine and bov...
Comparison of glycopyrrolate and atropine in ameliorating the adverse effects of imidocarb dipropionate in horses. Imidocarb, an effective treatment for piroplasmosis, may cause colic and diarrhoea in horses. Atropine and glycopyrrolate are anticholinergics that could reduce the adverse effects of imidocarb. However, atropine and glycopyrrolate inhibit gastrointestinal motility, potentially causing ileus and colic. Objective: To compare glycopyrrolate and atropine in ameliorating the adverse effects of imidocarb dipropionate in horses and to determine the effect of combinations of these drugs on the gastrointestinal tract. Methods: A blinded, randomised, crossover study was performed in 8 healthy horses. E...
Effects of repeated intra-articular administration of amikacin on serum amyloid A, total protein and nucleated cell count in synovial fluid from healthy horses. Serum amyloid A (SAA) in synovial fluid has recently been used as a marker for septic arthritis in horses but the effects of repeated intra-articular (IA) administration of amikacin on synovial SAA concentrations are unknown. Objective: To report the effect of repeated IA administration of amikacin on SAA, total protein (TP), nucleated cell count (NCC) and differential NCC in synovial fluid of healthy equine joints. Methods: A controlled, 2 period crossover study was performed on 5 clinically healthy horses. Each intercarpal joint received one of 2 treatments every 48 h for 5 consecutive times...
Influence of head and neck position on radiographic measurement of intervertebral distances between thoracic dorsal spinous processes in clinically sound horses. Reductions in distances between dorsal spinous processes on radiographs are used as criteria for the diagnosis of impingement of the thoracic dorsal spinous processes in horses but are potentially altered by spine motion and different head and neck positions. Objective: To determine the influence of head and neck positions on intervertebral distances between dorsal spinous processes on radiographs of thoracic spines of clinically sound horses. Methods: Lateral-lateral radiographs were obtained from 23 horses in 3 head and neck positions. The width of the thoracic dorsal spinous processes and i...
Combining two serological assays optimises sensitivity and specificity for the identification of Streptococcus equi subsp. equi exposure. The detection of anti-Streptococcus equi antibodies in the blood serum of horses can assist with the identification of apparently healthy persistently infected carriers and the prevention of strangles outbreaks. The aim of the current study was to use genome sequencing data to develop an indirect enzyme linked immunosorbent assay (iELISA) that targets two S. equi-specific protein fragments. The sensitivity and specificity of the antigen A and antigen C iELISAs were compared to an SeM-based iELISA marketed by IDvet - diagnostic Vétérinaire (IDvet). Individually, each assay compromised specifi...
Evaluation of a point-of-care portable analyzer for measurement of plasma immunoglobulin G, total protein, and albumin concentrations in ill neonatal foals. To compare the diagnostic performance of a point-of-care (POC) analyzer with that of established methods for the measurement of plasma IgG, total protein, and albumin concentrations in neonatal foals. Methods: Evaluation study. Methods: 100 neonatal foals < 7 days of age. Procedures-Plasma IgG, total protein, and albumin concentrations were measured with a POC analyzer via an immunoturbidimetric method. Corresponding measurements of plasma IgG, total protein, and albumin concentrations were measured by means of automated biochemical analyzers via automated immunoturbidimetric, biuret, and b...
Further characterisation of an experimental model of tendinopathy in the horse. Injuries in energy-storing tendons are common in both horses and man. The high prevalence of reinjury and the relatively poor prognosis for returning to preinjury performance levels warrant further research, for which well characterised models would be very helpful. Objective: Given the clinical similarities in tendinopathy of energy-storing tendons, we hypothesised that a recently developed experimental model of equine tendon injury would display many of the characteristics of clinical tendinopathy and could therefore be of use for both species, thus providing comparative insight to the human...
Microsatellite analysis of genetic diversity and population structure of Arabian horse populations. The Arabian horse ignites imagination throughout the world. Populations of this breed exist in many countries, and recent genetic work has examined the diversity and ancestry of a few of these populations in isolation. Here, we explore 7 different populations of Arabians represented by 682 horses. Three of these are Middle Eastern populations from near the historical origin of the breed, including Syrian, Persian, and Saudi Arabian. The remaining Western populations are found in Europe (the Shagya Arabian and Polish Arabian) and in America (American Arabian). Analysis of genetic structure was ...
In vitro biomechanical comparison of a 4.5 mm narrow locking compression plate construct versus a 4.5 mm limited contact dynamic compression plate construct for arthrodesis of the equine proximal interphalangeal joint. To compare the in vitro biomechanical properties of a 4.5 mm narrow locking compression plate (PIP-LCP) with 2 abaxially located transarticular screws and a 4.5 mm limited contact dynamic compression plate (LC-DCP) with 2 abaxially located transarticular screws using equine pasterns. Methods: Experimental. Paired in vitro biomechanical testing of 2 methods for stabilizing adult equine forelimb PIP joints. Methods: Adult equine forelimbs (n = 8 pairs). Methods: Each pair of PIP joints were randomly instrumented with either a PIP-LCP or LC-DCP plate axially and 2 parasagitally positioned 5.5 mm ...
Comparison of efficacy and duration of effect on corneal sensitivity among anesthetic agents following ocular administration in clinically normal horses. To compare efficacy and duration of effect on corneal sensitivity of 0.5% proparacaine hydrochloride, 0.5% bupivacaine hydrochloride, 2% lidocaine hydrochloride, and 2% mepivacaine hydrochloride solutions following ocular administration in clinically normal horses. Methods: 68 clinically normal horses. Methods: 60 horses were assigned to receive 1 anesthetic agent in 1 eye. For each of another 8 horses, 1 eye was treated with each of the anesthetic agents in random order with a 1-week washout period between treatments. Corneal sensitivity was assessed via corneal touch threshold (CTT) measurem...
Aberrant wound healing in the horse: naturally occurring conditions reminiscent of those observed in man. Impaired wound healing represents an enormous clinical and financial problem for companion animals and humans alike. Unfortunately, most models used to study healing rely on rodents, which have significant differences in the healing and scarring process and rarely develop complications. In order to better simulate impaired healing, the model should strive to reproduce the natural processes of healing and delayed healing. Wounds on the limbs of horses display similarities to wounds in humans in their epithelialization/contraction ratio, genetic influence as well as dysregulated cytokine profile...
Sequence analysis of ORFs 5, 6 and 7 of equine arteritis virus during persistent infection of the stallion–a 7-year study. Nucleotide and amino acid sequences of ORFs 5, 6 and 7 of EAV during persistent infection in the stallion of the Malopolska breed were analysed in the study. A total of 11 blood and semen samples were collected between 2004 and 2011. The titre of specific EAV antibodies in this carrier stallion was maintained at a high level throughout the study and was equal approximately 1:128. The sequence analysis of ORF5 showed 16 variable sites including 12 with synonymous substitutions and 4 with non-synonymous substitutions. The degree of nucleotide sequence identity among the strains ranged from 98.92...
Effect of age and prostheses location on rima glottidis area in equine cadaveric larynges. To determine the effect of horse age and laryngeal prosthesis location on rima glottidis area in cadaveric larynges. Methods: Experimental study. Methods: Cadaveric equine larynges (n = 40). Methods: Specimens were grouped by age: group 1, ≤5 years (n = 18); group 2, >5 to ≤10 years (n = 12); group 3, >10 years (n = 10). A cranial prosthesis was placed through the dorsal cricoid spine at 70% of the distance of the total cricoid length measured from the caudal rim. A dorsal prosthesis was placed through the caudal rim of the cricoid on the dorsal midline. A lateral prosthesis was plac...
Ex vivo comparison of 7 polydioxanone, 2 polyglactin 910 for closure of ventral median celiotomy in horses. To compare bursting strength and failure mode between ventral median celiotomies closed with USP 7 braided polydioxanone (7PD) or USP 2 polyglactin 910 (2PG). Methods: Ex vivo experimental. Methods: Equine cadavers (n = 10). Methods: A 25 cm ventral median celiotomy was created in fresh equine cadavers. A 200 L polyurethane bladder was inserted into the abdomen. Celiotomies were closed in a simple continuous pattern with 2 sections of 7PD or 2PG. The bladder was inflated with compressed air until construct failure. The horses' signalment, body weight, suture type, failure mode (suture or abdom...
Ex vivo comparison of bursting strength of ventral median and right ventral paramedian celiotomies in horses. To compare bursting strength and failure mode between ventral median (VM) and right ventral paramedian (RVP) celiotomies closed with 1 section of USP 7 braided polydioxanone (7PD). Methods: Ex vivo experimental. Methods: Equine cadavers (n = 12). Methods: A 25 cm VM or RVP (positioned 5 cm lateral to the linea alba) celiotomy was created in fresh equine cadavers. A 200 L polyurethane bladder was inserted into the abdomen. Celiotomies were closed in a simple continuous pattern with 1 section of 7PD. The bladder was inflated with compressed air until construct failure. Horse signalment, body wei...
Pharmacokinetics and safety of oral administration of meloxicam to foals. The pharmacokinetics, efficacy, and safety of meloxicam have been evaluated in adult horses, but not foals. Physiologic differences between neonates and adults might alter drug pharmacokinetics and therapeutic index. Objective: The pharmacokinetics of meloxicam will be different in foals compared with adult horses, and foals could be at increased risk for adverse drug effects. Methods: Twenty lightbreed foals less than 6 weeks of age at commencement of the study. Methods: Single and repeated oral dose pharmacokinetics were determined for meloxicam (0.6 mg/kg) in 10 foals. The safety of the d...
Mitochondrial phylogenomics of modern and ancient equids. The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy's zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further charact...
Quantitative versus qualitative approaches: a comparison of two research methods applied to identification of key health issues for working horses in Lesotho. The relative merits and potential complementarity of participatory methods and classical epidemiological techniques in veterinary-related research is a current topic of discussion. Few reported studies have applied both methodologies within the same research framework to enable direct comparison. The aim of this study was to compare issues identified by a classical epidemiological study of horses and their owners with those identified by owner communities using participatory approaches. In 2009, a cross-sectional survey was undertaken as part of an impact assessment study of farrier and saddle...
