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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.
Changes in Borrelia burgdorferi ELISA antibody over time in both antibiotic treated and untreated horses. Changes in ELISA serology are frequently used to determine antibiotic treatment success for Lyme disease in horses. This concept was based upon a previous report showing a marked decline in ELISA values in experimentally infected and antibiotic-treated ponies. Changes in Lyme serology following antibiotic treatment in naturally infected horses have not been reported. The objective of this study was to compare Borrelia ELISA antibody concentrations in naturally exposed horses both before and following antibiotic treatment for Lyme disease. A retrospective study was performed comparing oxytetrac...
Predictability of visual perturbation during locomotion: implications for corrective efference copy signaling. In guiding adaptive behavior, efference copy signals or corollary discharge are traditionally considered to serve as predictors of self-generated sensory inputs and by interfering with their central processing are able to counter unwanted consequences of an animal's own actions. Here, in a speculative reflection on this issue, we consider a different functional role for such intrinsic predictive signaling, namely in stabilizing gaze during locomotion where resultant changes in head orientation in space require online compensatory eye movements in order to prevent retinal image slip. The direct...
Does the stimulus type influence horses’ performance in a quantity discrimination task? The ability to understand the relation between quantities has been documented in a wide range of species. Such quantity discrimination competences are commonly demonstrated by a choice of the larger quantity or numerosity in a two-choice task. However, despite their overall success, many subjects commit a surprisingly large number of errors even in simple discriminations such as 1 vs. 3. Recently, it had been suggested that this is a result of the testing procedure. When monkeys could choose between different quantities of edible rewards, they showed low-level success. If, however, they chose ...
Equine myeloperoxidase: a novel biomarker in synovial fluid for the diagnosis of infection. Equine joint infection is a life-threatening disorder, and confirmation of the diagnosis can be difficult. Synovial fluid biomarkers may assist the discrimination between infectious and noninfectious joint disease. Objective: This study investigates whether the immunological detection of total and enzymatically active myeloperoxidase (MPO) assists the diagnosis of joint infection in horses. Methods: The following 4 sample groups were included: healthy; osteochondritis dissecans (OCD); traumatic synovitis; and culture-confirmed infected joints. Synovial fluid was analysed for total MPO by a hor...
Comparison of different treatments for oestrous induction in seasonally anovulatory mares. The aim of this study was to evaluate the effects of different treatments for induction and synchronization of oestrus and ovulation in seasonally anovulatory mares. Fifteen mares formed the control group (C), while 26 mares were randomly assigned to three treatment groups. Group T1 (n = 11) were treated with oral altrenogest (0.044 mg/kg; Regumate(®) ) during 11 days. Group T2 (n = 7) was intravaginally treated with 1.38 g of progesterone (CIDR(®) ) for 11 days. In group T3 (n = 8), mares were also treated with CIDR(®) , but only for 8 days. All mares received PGF2α 1 day afte...
Heart rate, heart rate variability and behaviour of horses during air transport. Heart rate (HR), HR variability (HRV) and behaviour score (BS) of nine horses were evaluated during an eight-hour air transport between The Netherlands and New York. HR and HRV parameters were calculated every five minutes during the air transport. Compared with transit (40±3), mean HRs were higher during loading into the jet stall (67±21, P<0.001), loading into the aircraft (47±6, P=0.011), taxiing (50±8, P=0.001), and during periods of in-flight turbulence (46±7, P=0.017). During the flight, individual horses showed differences in mean HR (P=0.005) and peak HR (P<0.001). By contra...
Comparative genomic analysis and phylogenetic position of Theileria equi. Transmission of arthropod-borne apicomplexan parasites that cause disease and result in death or persistent infection represents a major challenge to global human and animal health. First described in 1901 as Piroplasma equi, this re-emergent apicomplexan parasite was renamed Babesia equi and subsequently Theileria equi, reflecting an uncertain taxonomy. Understanding mechanisms by which apicomplexan parasites evade immune or chemotherapeutic elimination is required for development of effective vaccines or chemotherapeutics. The continued risk of transmission of T. equi from clinically silent,...
Flow-mediated K(+) secretion in horses intoxicated with lolitrem B (perennial ryegrass staggers). To investigate the effects of lolitrem B intoxication on renal K(+) secretion in response to increased tubular flow rates. Methods: Results are derived from a repeated measure pilot study of seven horses fed non-perennial ryegrass feed for a week prior to exposing them to perennial ryegrass seed and hay that contained an average of 2 ppm lolitrem B. At the end of the control and treatment period frusemide (1 mg/kg I/V) was administered and serial fractional excretion of K(+)(FEK(+)) and fractional excretion of Na(+)(FENa(+)) calculated. Baseline concentration of aldosterone in plasma, serum K(...
Lateralized suckling in domestic horses (Equus caballus). Brain lateralization enables preferential processing of certain stimuli and more effective utilization of these stimuli in either the left or the right cerebral hemisphere. Horses show both motor and sensory lateralization patterns. Our aim was to determine whether a lateralized response could be detected in foals during the naturally side-biased behaviour, suckling. The foals' preferred suckling side could be the effect of either visual or motor lateralization. In the case of a visual lateralized response, foals are expected to suck more often from the mother's right side, so potential danger...
Lymphoma risk in livestock farmers: results of the Epilymph study. We explored the risk of lymphoma and its most prevalent subtypes associated with occupational contact with livestock, and whether risk was modified by age at first contact, in 2,348 incident lymphoma cases and 2,462 controls who participated in the EPILYMPH case-control study. A detailed occupational history was collected in cases and controls, including working in a livestock farm, species of livestock, its approximate number and circumstances of contact. For each disease outcome, and each type of livestock, odds ratios (OR) and their 95% confidence intervals (95% CI) were calculated using un...
Stimulatory effect of PGF2α on PRL based on experimental inhibition of each hormone in mares. During the luteolytic period in mares, the peak of 65% of pulses of a PGF2α metabolite (PGFM) and the peak of a pulse of PRL have been reported to occur at the same hour. It is unknown whether the synchrony reflects an effect of PGF2α on PRL or vice versa. Controls, a flunixin meglumine (FM)-treated group (to inhibit PGF2α), and a bromocriptine-treated group (to inhibit PRL), were used at 14 days postovulation in June and in September (n = 6 mares/group/mo). Blood samples were collected hourly from just before treatment (Hour 0) to Hour 10. Concentrations of PGFM in the FM group were lower ...
Exogenous L-lactate clearance in adult horses. To determine endogenous production of L-lactate and the clearance of exogenous sodium L-lactate (ExLC) in healthy adult horses. Methods: A sodium L-lactate solution (1 mmol/kg body weight qs to 500 mL final volume in 0.9% NaCl) was adminstered IV over 15 minutes. Blood samples for L-lactate concentration [LAC] measurement were collected immediately prior to infusion, at 5, 10, and 15 minutes during infusion and at 1 minute intervals for 15 minutes, at 30, 45, 60, 120, and 180 minutes postinfusion. Disposition modeling and pharmacokinetic analysis was performed using proprietary software. Metho...
The horse as a model of naturally occurring osteoarthritis. Osteoarthritis (OA) is an important cause of pain, disability and economic loss in humans, and is similarly important in the horse. Recent knowledge on post-traumatic OA has suggested opportunities for early intervention, but it is difficult to identify the appropriate time of these interventions. The horse provides two useful mechanisms to answer these questions: 1) extensive experience with clinical OA in horses; and 2) use of a consistently predictable model of OA that can help study early pathobiological events, define targets for therapeutic intervention and then test these putative thera...
Evaluation of growth models for follicle development and ovulation in Lusitano mares. Several growth models are commonly used in the biological sciences, to model the follicle growth occurring in the estrous cycle. The aim of this project was to find the model that best fit the follicular size growth data for Lusitano mares. Retrospective data collected from reproduction book records of n=84 mares and n=124 cycles was used to find the series to be fitted to the models. The exponential, Gompertz, logistic, von Bertalanffy, Richards and Weibull models were used, and the most parsimonious and best fit was achieved with the logistic model (r(2)=0.999). The logistic model fits the L...
Relationship of mixed bacterial infection to prognosis in foals with pneumonia caused by Rhodococcus equi. Isolation of multiple bacterial species is common in foals with Rhodococcus equi pneumonia. Objective: There is no association between isolation of other microorganisms and outcome. Methods: 155 foals with pneumonia caused by R. equi. Methods: Case records of foals diagnosed with R. equi pneumonia based on culture of the respiratory tract were reviewed at 2 referral hospitals (University of Florida [UF] and Texas A&M University [TAMU]). Results: R. equi was cultured from a tracheobronchial aspirate (TBA) in 115 foals and from lung tissue in 38 foals. Survival was significantly higher at UF...
Serum protein concentrations as predictors of serum immunoglobulin G concentration in neonatal foals. To determine the predictive value of serum concentrations of total protein (sTP), albumin (sAlb), and globulin (sGlob) measured by automated calorimetric assays to estimate serum immunoglobulin G (sIgG) concentrations in neonatal foals and identify failure of transfer of passive immunity when compared to turbidoimmunometric assay determinations of sIgG. Methods: Retrospective and prospective analysis of laboratory data. Methods: University tertiary care facility. Methods: Group 1 (retrospective): foals (n = 45) ≤7 days of age in which sIgG, sGlob, sAlb, and sTP concentrations were measured o...
Induction of double ovulation in mares using deslorelin acetate. This study aimed to determine whether deslorelin acetate could induce double ovulation in mares. In Experiment 1, eight mares were treated with prostaglandin on Day 8 (D8) after ovulation, then treated with saline or with 100 μg of a controlled-release formulation of deslorelin acetate vehicle intramuscularly (IM) every 12h from D8 after ovulation until at least two follicles reached 33 mm. At this time, ovulation was induced with 2500 IU of hCG. Artificial insemination was performed 24h after induction, and embryos were collected on the eighth day after ovulation was first detected. In Exper...
Secondary osteon size and collagen/lamellar organization (“osteon morphotypes”) are not coupled, but potentially adapt independently for local strain mode or magnitude. In bone, matrix slippage that occurs at cement lines of secondary osteons during loading is an important toughening mechanism. Toughness can also be enhanced by modifications in osteon cross-sectional size (diameter) for specific load environments; for example, smaller osteons in more highly strained "compression" regions vs. larger osteons in less strained "tension" regions. Additional osteon characteristics that enhance toughness are distinctive variations in collagen/lamellar organization (i.e., "osteon morphotypes"). Interactions might exist between osteon diameter and morphotype that repr...
A review of recent advances and current hypotheses on the pathogenesis of acute laminitis. With the increasing number of studies being published on the different experimental models used to induce and study acute laminitis, the pathophysiological events associated with these various models (i.e. starch overload, oligofructose overload, black walnut extract and hyperinsulinaemia) can be compared more realistically. Within this review, the mechanisms for metabolic vs. inflammatory laminitis are discussed, and the question of how pasture laminitis may fit into any of the proposed mechanisms is addressed.
Profound re-organization of cell surface proteome in equine retinal pigment epithelial cells in response to in vitro culturing. The purpose of this study was to characterize the cell surface proteome of native compared to cultured equine retinal pigment epithelium (RPE) cells. The RPE plays an essential role in visual function and represents the outer blood-retinal barrier. We are investigating immunopathomechanisms of equine recurrent uveitis, an autoimmune inflammatory disease in horses leading to breakdown of the outer blood-retinal barrier and influx of autoreactive T-cells into affected horses' vitrei. Cell surface proteins of native and cultured RPE cells from eye-healthy horses were captured by biotinylation, an...
Mechanical and morphological properties of trabecular bone samples obtained from third metacarpal bones of cadavers of horses with a bone fragility syndrome and horses unaffected by that syndrome. To determine morphological and mechanical properties of trabecular bone of horses with a bone fragility syndrome (BFS; including silicate-associated osteoporosis). Methods: Cylindrical trabecular bone samples from the distal aspects of cadaveric third metacarpal bones of 39 horses (19 horses with a BFS [BFS bone samples] and 20 horses without a BFS [control bone samples]). Methods: Bone samples were imaged via micro-CT for determination of bone volume fraction; apparent and mean mineralized bone densities; and trabecular number, thickness, and separation. Bone samples were compressed to failur...
Locomotor Inhibition in Adult Horses Faced to Stressors: A Single Postpartum Experience May be Enough! Despite the number of postpartum handling that a newborn experiences, few studies focus on their long-term consequences. In rats, regular long separations from the mother, during the early life, led to modifications of the locomotor activity when the animal is confronted to a stressor. In horses, one component of the behavioral response to stressful situation is active locomotion. We wondered if the routine postpartum handling undergone by foals, would affect their level of reactivity or the way they express their stress, when older. One single prolonged bout of handling just after birth clear...
Synovial fluid D-dimer concentration in horses with osteochondritis dissecans and osteoarthritis. To assess the synovial fibrinolytic pathway activation in adult horses with developmental and degenerative arthropathies such as osteochondritis dissecans (OCD) and osteoarthritis (OA) by measuring synovial D-dimer concentrations. Methods: Prospective observational clinical study of horses admitted for OCD or OA. Synovial fluid was collected during lameness examination or prior to the surgical procedure, and D-dimer concentration and routine synovial fluid analysis were performed. Results: Fifty-eight horses (14 with OCD, 10 with OA and 34 controls) were included in this study. Synovial D-dime...
Comparative analysis of ORF5 nucleotide sequences and amino acid sequences of the GP5 protein of equine arteritis virus (EAV) detected in the semen of stallions from Eastern Poland. The purpose of this study was to conduct a comparative analysis of the ORF5 gene fragment nucleotide sequences and the GP5 protein amino acid sequences formed on this matrix, for the equine arteritis virus (EAV) strains isolated from the semen of infected stallions from Eastern Poland. The study covered 41 stallions whose blood serum tested positive for antigens specific to the EAV. The presence of EAV genetic material was shown in material from 5 horses, in one of which permanent presence of viral RNA was detected over the entire 4-year study period (the material was sampled four times at yea...
Ovulation-inducing factor in seminal plasma: a review. Ovulation in mammals involves pulsatile release of GnRH from the hypothalamus into the hypophyseal portal system with subsequent release of LH from the anterior pituitary into systemic circulation. Elevated circulating concentrations of LH induce a cascade of events within the mature follicle, culminating in follicle rupture and evacuation. The broad classification of species as either spontaneous or induced ovulators is based on the type of stimulus responsible for eliciting GnRH release from the hypothalamus. In spontaneously ovulating species (e.g., human, sheep, cattle, horse, pigs), relea...
Evaluation of motion correction processing in equine bone scintigraphy by Scheffé’s method of paired comparisons. Equine bone scintigraphy is usually performed with horses in standing position under sedation. However, swaying motion often leads to poor-quality images. To examine the usefulness of motion correction (MC) processing, equine bone scintigrams were evaluated using Scheffé's method of paired comparisons. A significant difference in evaluation scores was detected by analysis of variance (F test, P<0.01). According to all observers, Yardstick analysis scores were higher for images use of MC processing than for those no use of MC processing, for all parts. Overall scores of 5 observers were as ...
The effect of radio electric asymmetric conveyer treatment on sperm parameters of subfertile stallions: a pilot study. The Radio Electric Asymmetric Conveyer (REAC) has been mostly applied to treat symptoms related to psychological stress. In the study, we demonstrated the effect of REAC-Veterinary Neuro Psycho Physical Optimization (VNPPO) treatment protocol on sperm parameters of subfertile (n=11) and fertile (n=4) stallions. Subfertile stallions showed a reduced sperm concentration, progressive motility and normal morphology compared to fertile stallions. An increase in progressive sperm motility and quality of sperm morphology was found in subfertile stallions after the REAC-VNPPO treatment. The positive e...
Effects of meloxicam and phenylbutazone on equine gastric mucosal permeability. Newer NSAIDs that more selectively target the induced isoform of the cyclooxygenase enzyme (COX2) activity might reduce adverse effects while preserving therapeutic benefits of these drugs. Objective: To compare the effect of oral administration of multiple dose rates of meloxicam and phenylbutazone (PBZ) on gastric mucosal integrity in horses. Methods: Twenty-five light breed horses. Methods: In vivo toxicity study. Horses were randomly assigned to 5 treatment groups, receiving placebo, PBZ (4.4 mg/kg PO q12h day 1, 2.2 mg/kg PO q12h for 4 days, 2.2 mg/kg PO q24h for 9 days), or 3 dose rates ...
