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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.
A novel subgroup among genotypes of equine arteritis virus: genetic comparison of 40 strains. The authors determined partial nucleic sequences of the variable regions of open-reading frame (ORF5) from 151 nucleotide to 668 nucleotide and deduced amino acid sequences of 518 nucleotide respectively of 20 equine arteritis virus (EAV) isolates. About 19 Hungarian and one Austrian EAV strains were subjected to sequence analysis, the further data of 20 EAV strains: six North American and 14 European were obtained from the GenBank. Comparative sequence analysis of the Hungarian EAV strains indicated that among the three variable regions the first has been affected mostly by point mutations. G...
Scintigraphic evaluation of the distal tarsal region in horses with distal tarsal pain. Distal tarsal pain is a common reason for hind limb lameness, but diagnosis cannot always be made on radiographic examination. Scintigraphy may allow detection of subtle changes undetected by other diagnostic methods. We hypothesized that (1) distal tarsal pain would be associated with a loss of the expected pattern of radiopharmaceutical uptake (RU) detected in normal horses, (2) distal tarsal RU would be greater in limbs with tarsal pain than without pain, (3) RU in painful tarsi with radiographic evidence of osteoarthritis (OA) would be greater than in distal tarsal pain with no radiographi...
PNA-binding glycans are expressed at high levels on horse mature and immature T lymphocytes and a subpopulation of B lymphocytes. In mammals, the binding of peanut agglutinin (PNA) on the plasma membrane defines subpopulations among lymphocytes from peripheral blood and lymphoid organs. PNA binds Galbeta 1,3GalNAc residues provided that they are not sialylated. Here, we studied the expression of PNA-binding glycans on healthy horse peripheral blood, thymus, lymph node and spleen lymphocytes. We first demonstrated the binding specificity of PNA for galactose residues by competition experiments and the inhibitory role of sialic acids in PNA binding by sialidase digestion. Unlike human and murine lymphocytes, all equine lym...
Changes in the heart rate and plasma epinephrine and norepinephrine concentrations of the stallion during copulation. The physiological indexes of the copulatory behavior of the stallion have not been investigated in detail and may differ from those of other species, such as humans and rats. In order to understand the breeding capability of various stallions, their behavior during copulation was observed, and heart rate (HR) and the plasma concentrations of norepinephrine (NA) and epinephrine (Ad) were measured sequentially for a total of 13 copulations carried out during 2 days. The mean HR at rest was 35.3 ± 0.9 beats per minute (b.p.m.) and it peaked during mounting (162.1 ± 5.4 b.p.m.). The HR a...
Comparison of computer-assisted surgery with conventional technique for the treatment of axial distal phalanx fractures in horses: an in vitro study. To compare the precision obtained with computer-assisted screw insertion for treatment of mid-sagittal articular fractures of the distal phalanx (P3) with results achieved with a conventional technique. Methods: In vitro experimental study. Methods: Thirty-two cadaveric equine limbs. Methods: Four groups of 8 limbs were studied. Either 1 or 2 screws were inserted perpendicular to an imaginary axial fracture of P3 using computer-assisted surgery (CAS) or conventional technique. Screw insertion time, predetermined screw length, inserted screw length, fit of the screw, and errors in placement wer...
Arthrodesis of the equine proximal interphalangeal joint: a mechanical comparison of 2 parallel 5.5 mm cortical screws and 3 parallel 5.5 mm cortical screws. To compare the biomechanical characteristics and mode of failure of 2 techniques using parallel 5.5 mm screws for pastern joint arthrodesis in horses. Methods: Randomized block design, for horse (1-5), method of fixation (two 5.5 mm screws versus three 5.5 mm screws), side (right, left), and end (front, hind). Constructs were tested to failure in 3-point bending. Methods: Twenty limbs (5 cadavers). Methods: A combined aiming device was used to facilitate screw placement. Two parallel 5.5 mm screws were inserted in lag fashion in 1 limb of a pair, and three 5.5 mm screws were inserted in the co...
Neovascularisation in chronic tendon injuries detected with colour Doppler ultrasound in horse and man: implications for research and treatment. Recent research on chronic painful Achilles tendons in humans using ultrasonography and immunohistochemistry, has demonstrated an association between neurovascular ingrowth and tendon pain. In horses, chronic debilitating tendon conditions are well-known to be very difficult to treat, and the background to impaired function and pain is not scientifically clarified. In a collaborative research project between the Sports Medicine Unit in Umeå and Strömsholm Equine Hospital, grey-scale ultrasonography (US) and colour Doppler (CD) examination were performed in ten horses with chronic tendon inju...
Age-related changes in metabolic properties of equine skeletal muscle associated with muscle plasticity. The purpose of the present study was to determine the age-related changes in myosin heavy chain (MHC) composition and muscle oxidative and glycolytic capacity in 18 horses ranging in age from two to 30 years. Muscle samples were collected by excisional biopsy of the semimebranosus muscle. MHC expression and the key enzymatic activities were measured. There was no significant correlation between horse age and the proportions of type-IIA and type-IIX MHC isoforms. The percentage of type-I MHC isoforms decreased with advancing age. Muscle citrate synthase activity decreased, whereas lactate dehyd...
Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 6. Bone parameters in the third metacarpal and third metatarsal bones. To determine the effect of a known training regimen on the size and mineral content of the third metacarpal (Mc3) and third metatarsal (Mt3) bones of 2-year-old Thoroughbred horses trained on racetracks. Methods: Mc3 and Mt3 of seven horses trained on grass and sand tracks were scanned at several sites using conventional quantitative and peripheral computed tomography (CT). Bone dimensions and density in the diaphysis and epiphysis were compared with those from seven untrained horses. Calcein label was injected in two clusters, during Weeks 9 and 12. The extent and rate of diaphyseal modelling...
Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 8. Quantitative back-scattered electron scanning electron microscopy and confocal fluorescence microscopy of the epiphysis of the third metacarpal bone. To characterise and explain the increase in density evident by computerised tomography (CT) and radiography in companion studies as a response to training, in bone in the palmar and dorsal regions of the condyles of the third metacarpal bone (Mc3) of 2-year-old Thoroughbred horses. Methods: Compositional back-scattered electron (BSE) imaging in scanning electron microscopy (SEM) and confocal scanning laser microscopy (CSLM) were conducted on polymethyl methacrylate (PMMA)-embedded mediolateral slices of the right distal Mc3 from seven 2-year-old Thoroughbred horses trained on a racetrack and s...
Immunoglobulin E-bearing cells and mast cells in skin biopsies of horses with urticaria. The pathogenesis of equine urticaria is not well understood. In man, urticaria has been associated with immunological and nonimmunological mechanisms leading to the release of various mediators by mast cells. Skin biopsies of 32 horses with a history of urticaria were stained with toluidine blue, a double-labelling method for chymase and tryptase, and immunohistochemistry for immunoglobulin (Ig)E. These horses were compared with horses with pemphigus foliaceus, insect bite hypersensitivity and control horses with healthy skin. Neither formalin fixation time nor biopsy site influenced the stain...
Optimization of assay conditions for leukotriene B4 synthesis by neutrophils or platelets isolated from peripheral blood of monogastric animals. Neutrophils are involved in inflammation through leukotriene (LT) production. The predominant proinflammatory leukotriene released from neutrophils is LTB4, which serves as a biological marker of inflammation. The purpose of this study was to optimize the conditions ex vivo for LTB4 production by neutrophils from horses and dogs, and platelets from chickens. Optimal production of LTB4 was characterized by incubation time (2.5, 5, 10, 15 or 20 min), temperature (25 or 37 degrees C), and calcium ionophore A23187 concentration (0.1, 1, 10 or 20 microM). Incubation longer than 2.5 min did not incr...
Nitric oxide levels and nitric oxide synthase expression in uterine samples from mares susceptible and resistant to persistent breeding-induced endometritis. Breeding-induced endometritis (BIE) in the mare is resolved by 36 hr after insemination in resistant mares. However, 10-15% susceptible broodmares fail to do so because of impaired uterine contractility between 7 and 19 hr after exposure to seminal or bacterial challenge, which reduces their fertility. Methods: Nitric oxide (NO) in uterine secretions, and expression of nitric oxide synthase (NOS) in uterine biopsies were compared between susceptible and resistant groups 13 hr after insemination. Results: Susceptible mares had a higher NO in their uterine secretions and greater inducible NOS (i...
Evaluation of a PCR to detect Salmonella in fecal samples of horses admitted to a veterinary teaching hospital. The diagnostic accuracy of a PCR used to identify horses shedding Salmonella spp. in their feces during hospitalization was estimated, relative to bacterial culture of serially collected fecal samples, using longitudinal data. Five or more fecal samples were collected from each of 116 horses admitted as inpatients, for reasons other than gastrointestinal disease, between July 26, 2001 and October 25, 2002. All 873 fecal samples collected were tested with a PCR based on oligonucleotide primers defining a highly conserved segment of the histidine transport operon gene of Salmonella typhimurium, ...
LH and IGF-1 release during oestrus and early luteal phase in lactating and non-lactating horse mares. The aim of the present study was to determine effects of lactation on basal LH and IGF-1 concentrations and on the LH response to a GnRH-analogue at different stages of the oestrous cycle in mares. A total of 17 cyclic Haflinger mares were included in the study. Experiments were performed on lactating mares in first postpartum oestrus, the subsequent early luteal phase, and second postpartum oestrus. Non-lactating mares were used in oestrus and early luteal phase. Blood samples were taken for 1 h at 15 min intervals. Mares were then injected with the GnRH-analogue buserelin (GnRHa; 5 microg i....
Evaluation of developmental changes in the coexpression of myosin heavy chains and metabolic properties of equine skeletal muscle fibers. To determine the growth-related changes in metabolic and anatomic properties in equine muscle fiber type, including hybrid fibers identified with immunohistochemical analysis. Methods: 24 2-, 6-, 12-, and 24-month-old female Thoroughbreds. Methods: Samples were obtained from the gluteus medius muscle of all horses. Expression of myosin heavy chain (MHC) isoforms MHC-I, -IIa, -IIb, and -IIx in each muscle fiber was detected by use of 4 primary monoclonal antibodies: BA-D5, SC-71, BF-F3, and BF-35, respectively. Five muscle fiber types (types I, I/IIA, IIA, IIA/IIX, and IIX) were immunohistochem...
Effect of early training on the jumping technique of horses. To investigate the effects of early training for jumping by comparing the jumping technique of horses that had received early training with that of horses raised conventionally. Methods: 40 Dutch Warmblood horses. Methods: The horses were analyzed kinematically during free jumping at 6 months of age. Subsequently, they were allocated into a control group that was raised conventionally and an experimental group that received 30 months of early training starting at 6 months of age. At 4 years of age, after a period of rest in pasture and a short period of training with a rider, both groups were ...
The early conception factor (ECF) lateral flow assay for non-pregnancy determination in the mare. The horse early conception factor (ECF) test is designed for qualitative determination of the ECF glycoprotein in the mare that has conceived. The objectives of this study were to determine the performance of the horse ECF test for the detection of the non-pregnant mare, and to determine the agreement among subjects or "readers" regarding the interpretation of the test. Blood samples from 60 mares were collected on Days 0, 5, 8, 11 and 18 following ovulation. Pregnancy status diagnosed with the ECF test was compared (2 x 2 table) to pregnancy status diagnosed by palpation per rectum and ultras...
Comparison of in vitro laboratory analyses with the fertility of cryopreserved stallion spermatozoa. Assessing the fertilizing potential of a semen sample is important for effective stallion management and for rapid progress in evaluating new cryopreservation technologies. Unfortunately, sperm motility does not estimate fertility well. These experiments established assays to measure cell viability, acrosomal integrity and mitochondrial function for cryopreserved stallion spermatozoa, using flow cytometry, and determined the variability associated with these assays. Correlations between results for these laboratory assays and stallion fertility were also determined. The inter-assay variability...
Follicular fluid concentrations of free insulin-like growth factor (IGF)-I during follicular development in mares. The objective of the present study was to evaluate changes in concentrations of free insulin-like growth factor (IGF)-I in follicular fluid (FFL) during follicle development in the mare. Mares (n = 14) were classified as either in the follicular phase (n = 8) or luteal phase (n = 6). Follicles (n = 92) were categorized as small (6-15 mm; n = 54), medium (16-25 mm; n = 23) or large (>25 mm; n = 15) and FFL was collected. Free IGF-I levels in FFL in large follicles of follicular phase mares were greater (P < 0.05) than in large follicles of luteal phase mares and small or medium follicles ...
Application of MTT reduction assay to evaluate equine sperm viability. The assay of MTT reduction depends on the ability of metabolically active cells to reduce the tetrazolium salt (3[4,5-dimethylthiazol-2-y1]-2,5-diphenyltetrazolium bromide) to formazan. This study was conducted to examine and validate of a simple and less costly MTT test in determining equine sperm viability and compare the efficiency of this test with a flow cytometer. Fresh ejaculates from 11 stallions (warm blood) were included in this study. Semen was diluted to 100 million cells/ml in a Hepes 0.1% BSA. The rates of MTT reduction were measured in microtiter plates after incubation for 1 an...
Quantitative analysis of voltage-gated potassium currents from primary equine (Equus caballus) and elephant (Loxodonta africana) articular chondrocytes. In this comparative study, we have established in vitro models of equine and elephant articular chondrocytes, examined their basic morphology, and characterized the biophysical properties of their primary voltage-gated potassium channel (Kv) currents. Using whole cell patch-clamp electrophysiological recording from first-expansion and first-passage cells, we measured a maximum Kv conductance of 0.15 +/- 0.04 pS/pF (n = 10) in equine chondrocytes, whereas that in elephant chondrocytes was significantly larger (0.8 +/- 0.4 pS/pF, n = 4, P </= 0.05). Steady-state activation parameters of eleph...
[Precision-controlled echocardiographic left ventricular function parameters by repeated measurement on three consecutive days in trained and untrained warmblood horses]. Echocardiographic measurements have to be reliable and reproducible with only a low day to day variability for detecting pathological changes of left ventricular myocardial function in horses. The day dependent fluctuation margin represents an important indicator for the reproducibility of a method. To find out the day to day variability of echocardiographic parameter in healthy warmblood horses, in the present study repeated echocardiographic measurements at three consecutive days were carried out (at the same time and by the same examiner) at 11 untrained and 7 trained warmblood horses. The ...
Polymorphisms of the upstream regulatory region of the major histocompatibility complex DRB genes in domestic horses. Sequence information was obtained on the variation of the ELA-DRB upstream regulatory region (URR) after polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) cloning and sequencing of approximately 220 bp upstream of the first exon of horse DRB genes. The sequence of the proximal URR of equine DRB is composed of highly conserved sequence motifs, showing the presence of the W, X, Y, CAAT and TATA conserved boxes of major histocompatibility complex (MHC) class II promoters. Five different polymorphic horse DRB promoter sequences were detected in five horse breeds. The res...
In vitro comparison of three materials as apical sealants of equine premolar and molar teeth. Surgical endodontic therapy is a conservative dental technique used in horses with some degree of clinical success. Failure of this procedure can partially be explained by inadequate sealing of the root apices with resultant microleakage in the periapical area. Objective: To assess and compare in vitro sealing ability of 3 different dental restorative materials used as apical sealants during equine surgical endodontics. Methods: Thirty extracted equine cheek teeth were divided randomly into 3 groups and subjected to apicoectomy and apical sealing using 3 materials: reinforced zinc oxide-eugeno...
Genetic diagnosis of sex chromosome aberrations in horses based on parentage test by microsatellite DNA and analysis of X- and Y-linked markers. Sex chromosome aberrations are often associated with clinical signs that affect equine health and reproduction. However, abnormal manifestation with sex chromosome aberration usually appears at maturity and potential disorders may be suspected infrequently. A reliable survey at an early stage is therefore required. Objective: To detect and characterise sex chromosome aberrations in newborn foals by the parentage test and analysis using X- and Y-linked markers. Methods: We conducted a genetic diagnosis combined with a parentage test by microsatellite DNA and analysis of X- and Y-linked genetic ...
