Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
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.
Evaluation of glucose tolerance and intestinal luminal membrane glucose transporter function in horses with equine motor neuron disease. To confirm whether the plasma glucose concentration curve obtained during oral glucose tolerance tests (OGTTs) in horses with equine motor neuron disease (EMND) is decreased, compared with that obtained in clinically normal horses, and determine whether that decrease is a result of defective glucose metabolism or intestinal glucose transport dysfunction. Methods: 8 horses with EMND and 44 matched control horses. Methods: Electromyography and OGTTs were performed in all 8 affected horses and 10 control horses. Intravenous GTTs (IVGTTs) were performed in 6 affected horses and another 11 control ...
Biological activities of recombinant equine luteinizing hormone/chorionic gonadotropin (eLH/CG) expressed in Sf9 and Mimic insect cell lines. Equine luteinizing hormone (eLH) and chorionic gonadotropin (eCG) are composed of identical alpha and beta polypeptide chains, but eCG subunits are much more heavily glycosylated and sialylated. Consequently, eCG exhibits a much longer half-life than eLH in blood. Recombinant eLH/CG, expressed in Sf9 and Mimic insect cells, were compared with one another and to the natural hormones eCG and eLH. Mimic cells are stably-transformed Sf9 cells, expressing five mammalian genes encoding glycosyltransferases involved in the synthesis of complex N-carbohydrate chains. Recombinant eLH/CG expressed in Mi...
High-resolution RH map of horse chromosome 22 reveals a putative ancestral vertebrate chromosome. High-resolution gene maps of individual equine chromosomes are essential to identify genes governing traits of economic importance in the horse. In pursuit of this goal we herein report the generation of a dense map of horse chromosome 22 (ECA22) comprising 83 markers, of which 52 represent specific genes and 31 are microsatellites. The map spans 831 cR over an estimated 64 Mb of physical length of the chromosome, thus providing markers at approximately 770 kb or 10 cR intervals. Overall, the resolution of the map is to date the densest in the horse and is the highest for any of the domesticat...
Characterization of a 2.6 kbp variable region within a class 1 integron found in an Acinetobacter baumannii strain isolated from a horse. A complete gene cassette contained in a class 1 integron from a multidrug-resistant (MDR) isolate of Acinetobacter baumannii cultured from a horse was characterized by molecular methods. Methods: Template genomic DNA purified from the A. baumannii isolate was investigated by PCR. A gene cassette-associated amplicon was detected and completely characterized. Results: A 2.6 kbp DNA fragment containing four gene cassettes was amplified from the MDR A. baumannii isolate. Sequence analysis showed it was similar to sequences recently reported in Klebsiella pneumoniae, Serratia marcescens and an Esch...
Identification of equine P-selectin glycoprotein ligand-1 (CD162). P-selectin glycoprotein ligand-1 (PSGL-1, CD162) is a dimeric, mucin-like, transmembrane glycoprotein constitutively expressed on leukocytes. A high baseline level of P-selectin expression in circulating equine platelets suggests a primed state toward inflammation and thrombosis via P-selectin/PSGL-1 adhesion. To investigate the potential role of equine P-selectin in these events, we first identified the cDNA sequence of equine PSGL-1 (ePSGL-1) using degenerate PCR and RACE-PCR and then compared the predicted sequence with that of human PSGL-1 (hPSGL-1). ePSGL-1 protein subunit is predicted to...
PCR ribotyping of Clostridium difficile isolates originating from human and animal sources. Molecular typing of Clostridium difficile isolates from animals and humans may be useful for evaluation of the possibility for interspecies transmission. The objective of this study was to evaluate C. difficile isolates from domestic animals and humans using PCR ribotyping. Isolates were also tested using PCR for the presence of genes encoding toxins A and B. One hundred and thirty-three isolates of C. difficile from dogs (n = 92), horses (n = 21) and humans (n = 20), plus one each from a cat and a calf, were evaluated. Overall, 23 ribotypes were identified. Of these, nine were identified from...
An in vitro biomechanical comparison of the insertion variables and pullout mechanical properties of ao 6.5-mm standard cancellous and 7.3-mm self-tapping, cannulated bone screws in foal femoral bone. To compare screw insertion variables and pullout mechanical properties between AO 6.5-mm cancellous and 7.3-mm cannulated bone screws in foal femoral bone. Methods: A paired, in vitro mechanical study. Methods: Seven pairs of femora from immature (1-7 months) foals. Methods: The 6.5 cancellous and 7.3-mm cannulated screws were inserted at standardized proximal and distal metaphyseal, and mid-diaphyseal locations. Insertion torque, force, and time to drill, tap (6.5-mm cancellous), guide wire insertion (7.3-mm cannulated), and screw insertion were measured. Screw pullout properties (yield and f...
Genetic clustering of Borna disease virus natural animal isolates, laboratory and vaccine strains strongly reflects their regional geographical origin. The aim of this study was to gain more detailed insights into the genetic evolution and variability of Borna disease virus (BDV). Phylogenetic analyses were performed on field viruses originating from naturally infected animals, the BDV vaccine strain 'Dessau', four widely used laboratory strains and the novel BDV subtype No/98. Four regions of the BDV genome were analysed: the complete p40, p10 and p24 genes and the 5'-untranslated region of the X/P transcript. BDV isolates from the same geographical area exhibited a clearly higher degree of identity to each other than to BDV isolates from ot...
Comparison of HIV-1 and EIAV-based lentiviral vectors in corneal transduction. In this study we compare the ability of self-inactivating Human Immunodeficiency Virus 1 (HIV-1) and Equine Infectious Anaemia Virus (EIAV)-based vectors to mediate gene transfer to rabbit and human corneas and to a murine corneal endothelial cell line. Both vectors were pseudotyped with vesicular stomatitis virus-G (VSV-G) envelope and contained marker transgenes under the control of an internal CMV promoter. For specificity of action, the heterologous promoter in the EIAV-vector was exchanged for an inducible E-Selectin promoter, previously shown to regulate gene-expression in a plasmid syst...
Compensatory load redistribution of horses with induced weightbearing hindlimb lameness trotting on a treadmill. The compensatory mechanisms of horses with weightbearing hindlimb lameness are still not fully understood. Objective: That weightbearing, unilateral hindlimb lameness would not only alter stride characteristics to diminish structural stress in the affected limb but also induce compensatory load adjustments in the other supporting limbs. Objective: To document the load and time shifting mechanisms of horses with unilateral weightbearing hindlimb lameness. Methods: Reversible lameness was induced in 8 clinically sound horses by applying a solar pressure model. Three degrees of lameness (subtle, ...
Influence of rider on lameness in trotting horses. Equine lameness is commonly evaluated when the horse is being ridden, but the influence of the rider on the lameness has not been documented. Objective: To document the effect of 2 riders of different training levels on the vertical movement of the head and croup. Methods: Twenty mature horses were ridden at trot by an experienced dressage rider and a novice rider, as well as trotted in hand. Kinematic measurements of markers placed on the horse's head and sacral bone were carried out. The asymmetries of the vertical head and sacral bone motion were calculated as lameness parameters and compar...
Verification of skin-based markers for 3-dimensional kinematic analysis of the equine tarsal joint. Kinematic studies are usually based on tracking markers attached to the skin. However, complex joints, such as the tarsal joint, function in 3-dimensions (3D), and have therefore necessitated application of the invasive bone pin technique, limiting kinematic studies to the research laboratory. This study investigates the feasibility of using skin-based markers for 3D analysis of tarsal joint motion. Objective: Three-dimensional motions of the tarsal joint can be measured with an acceptable degree of accuracy using skin markers. Methods: Retroreflective markers were attached over the tibial and...
In vitro measurement of internal hoof strain. Strains during stance on the hoof wall surface have been measured by a number of authors in vitro and in vivo. Histological structure and mechanical properties vary through the wall thickness (radially); radial strain measurements may therefore aid the understanding of mechanical function of the capsule and adjacent tissues. Objective: To develop instrumentation capable of measuring internal hoof strain, and to carry out a preliminary comparison of normal and laminitic hooves. Methods: Six forelimbs from 4 horses, including 2 with laminitis from the same horse, were tested using an Instron tes...
Relationships between fore- and hindlimb ground reaction force and hoof deceleration patterns in trotting horses. The transmission of shockwaves following hoof impact is proposed to be one major source of stress to the limb. In the forelimb, there are indications that the period of horizontal deceleration of the hoof is related to the attenuation of shockwaves. In the hindlimb, information about the hoof deceleration has been lacking. Objective: To compare hoof deceleration patterns between the fore- and hindlimbs. Methods: Seven Standardbreds were trotted by hand over a force plate covered with sand, with triaxial accelerometers mounted on the fore and hind hooves. Variables representative of deceleratio...
Three-dimensional carpal kinematics of trotting horses. Descriptions of 3D kinematics assist in understanding joint function and dysfunction, and are an essential step toward 3D inverse dynamic analysis. Objective: To measure 3D carpal joint motion during trotting. Methods: Three-dimensional trajectories of bone-fixed markers on the radius and third metacarpus of the right forelimb of 3 healthy horses were recorded at 120 Hz using a 6-camera analysis system. Joint kinematics were calculated in terms of helical angles between the 2 segments using a spatial attitude method. Results: All horses showed carpal extension and internal rotation of the meta...
Detection of spinal ataxia in horses using fuzzy clustering of body position uncertainty. Subjective neurological evaluation in horses is prone to bias. An objective method of spinal ataxia detection is not subject to these limitations and could be of use in equine practice and research. Objective: Kinematic data in the walking horse can differentiate normal and spinal ataxic horses. Methods: Twelve normal and 12 spinal ataxic horses were evaluated by kinematic analysis walking on a treadmill. Each body position signal was reduced to a scalar measure of uncertainty then fuzzy clustered into normal or ataxic groups. Correct classification percentage (CCP) was then calculated using m...
Comparison of intra-articular drilling and diode laser treatment for arthrodesis of the distal tarsal joints in normal horses. Anecdotal reports suggest that laser-facilitated arthrodesis of the distal tarsal joints improves the prognosis compared with intra-articular drilling but no objective comparisons have been performed. Objective: To evaluate intra-articular drilling and laser-facilitated arthrodesis using in situ and in vivo techniques. Methods: Fourteen cadaver limbs were evaluated in situ for chondrocyte viability after both surgical techniques. In vivo, one randomly selected limb was subjected to laser-facilitated arthrodesis and the other underwent intra-articular drilling in 6 normal horses. Clinical exami...
Analysis of cartilage oligomeric matrix protein (COMP) degradation and synthesis in equine joint disease. Cartilage oligomeric matrix protein (COMP) is abundant within cartilage; its turnover and/or degradation have been investigated in various equine joint diseases and it has been suggested that COMP fragmentation might be useful for monitoring such conditions. Objective: To determine whether COMP metabolism is compromised in equine osteoarthritis (OA) and whether COMP degradation is a useful joint marker representing cartilage destruction. Objective: A monoclonal antibody (mAb) with a higher affinity for degraded COMP allows discrimination of diseased joints by quantifying COMP levels and fragme...
Immunoglobulin and peripheral B-lymphocyte concentrations in Fell pony foal syndrome. Fell pony foals are affected by a congenital fatal disease that leads to profound anaemia and immunodeficiency. Previous studies comparing healthy and affected foals have shown normal T-cell populations, but a severe B-lymphopenia. Objective: To measure the levels of individual immunoglobulin subisotypes in normal and affected Fell ponies and correlate these levels with the number of peripheral B-lymphocytes. Methods: Serum levels of individual immunoglobulin subisotypes were measured by ELISA and correlated with the number of peripheral B-lymphocytes (measured by flow cytometry). Results: Aff...
cDNA AFLP-based techniques for studying transcript profiles in horses. The identification of differentially expressed genes is a fundamental prerequisite for understanding the molecular regulation of most physiological and pathological processes. Among the procedures employed to compare mRNA populations, those that are gel-based appear to hold great promise and are considered excellent tools for studying gene expression in species, such as the equine one, for which little genomic information is available. In the present study, we evaluated two techniques for studying mRNA profiles in horse tissue, one referred to the cDNA-amplified fragment length polymorphism (A...
Age-related changes in serum insulin-like growth factor-I, insulin-like growth factor-I binding protein-3 and articular cartilage structure in Thoroughbred horses. Structural changes in articular cartilage associated with the ageing process require definition for investigators performing developmental and age-related studies, for which information is lacking. Objective: To 1) determine the onset and end of puberty as defined by serum insulin like growth factor (IGF-I) and IGF-binding protein-3 (IGFBP-3) concentrations and 2) correlate articular-epiphyseal cartilage complex structural changes with the onset and end of puberty. Methods: IGF-I and IGFBP-3 were measured in serum samples from normal female and male horses age 9-715 days to determine peak and ...
Histomorphology of the equine cervix. The cervix provides an effective, morphological barrier between the uterus and the outside world. The aim of this study was to characterize the epithelial morphology and the vascular structures of the equine cervix along the longitudinal and horizontal axis in more detail by light microscopy. For this purpose, cervical tissue specimens that had been removed from five different regions along the caudocranial axis of 10 genitally healthy mares were available. The histological staining was carried out with haematoxylin-eosin, azan according to Heidenhain, periodic acid-Schiff reaction and resorci...
Assessment of the ultrasonographic characteristics of the podotrochlear apparatus in clinically normal horses and horses with navicular syndrome. To characterize the normal ultrasonographic appearance of the podotrochlear apparatus in horses by use of standardized measurements and identify soft tissue changes associated with navicular syndrome. Methods: Prospective study. Methods: 7 clinically normal horses and 28 horses with navicular syndrome. Methods: The feasibility of identifying and measuring the soft tissue structures of the podotrochlear apparatus ultrasonographically via the transcuneal approach was assessed in 2 additional horses without navicular syndrome; both horses were euthanatized, and the structures identified ultrasono...
Immunoglobulin M-capture enzyme-linked immunosorbent assay testing of cerebrospinal fluid and serum from horses exposed to west nile virus by vaccination or natural infection. The West Nile (WN) virus, present in the United States since 1999, is a cause of encephalomyelitis in birds, alligators, humans, and horses. No data exist regarding detection of anti-WN virus immunoglobins in equine cerebrospinal fluid (CSF). The aims of this study were to evaluate the blood-brain barrier (BBB) in WN virus-infected (WNE) horses, to compare diagnostic testing in serum and CSF, and to describe the immunoglobulin M (IgM) response in serum and CSF of vaccinated horses. CSF was collected from the lumbosacral (LS) space (n = 13) or the allanto-occipital (AO) space (n = 14) of WNE ho...
Observer variation in visual assessment of forelimb horseshoe characteristics on Thoroughbred racehorses. To assess the accuracy and reliability of a visual method of evaluating horseshoe characteristics. Methods: 1,199 Thoroughbred racehorses. Methods: Characteristics of 1 forelimb horseshoe were visually assessed on horses immediately prior to racing by 5 field observers at 5 major racetracks in California. Characteristics evaluated included horseshoe type; toe grab height; and the presence of a rim, pad, and heel traction devices. Sensitivity and specificity for observer assessment of horseshoe characteristics were calculated by comparing observer assessments to a postmortem laboratory standard...
A comparison of solution conformation and hydrodynamic properties of equine, porcine and rabbit serum albumin using viscometric measurements. This paper presents the results of viscosity determinations on aqueous solutions of equine, porcine and rabbit serum albumin over a wide range of concentrations and at temperatures ranging from 5 degrees C to (42-45) degrees C. The results are compared with human and bovine serum albumin previously studied. Viscosity-temperature dependence is discussed on the basis of the modified Arrhenius formula. The effective specific volume, the activation energy and entropy of viscous flow for all investigated albumins are compared. Viscosity-concentration dependence, in turn, is discussed on the basis o...
Liquid-vapor interfacial tension of blood plasma, serum and purified protein constituents thereof. A systematic study of water-air (liquid-vapor, LV) interfacial tension gamma(lv) of blood plasma and serum derived from four different mammalian species (human, bovine, ovine and equine) reveals nearly identical concentration-dependence (dgamma(lv)/dlnC(B); where C(B) is plasma/serum dilution expressed in v/v concentration units). Comparison of results to a previously-published survey of purified human-blood proteins further reveals that dgamma(lv)/dlnC(B) of plasma and serum is surprisingly similar to that of purified protein constituents. It is thus concluded that any combination of blood-pr...
Expression and subcellular localization of the mu-opioid receptor in equine spermatozoa: evidence for its functional role. The development of fertilizing ability in sperm cells is associated with changes in the plasma membrane. However, to date the exact nature of sequentially activated primary receptors and channels and the signal transduction pathways derived from these remains elusive. We analyzed the expression and localization of the mu-opioid receptor in equine spermatozoa. A transcript corresponding to the third extracellular loop that selectively binds mu agonists was amplified, sequenced and compared with the known sequences in humans, rats and cattle. The amplification product showed a high degree of nuc...
Relationships between sexual behaviour, dominant follicle area, uterus ultrasonic image and pregnancy rate in mares of two breeds differing in reproductive efficiency. Weak or equivocal expression of oestrous behaviour, related to different level of mares' reactivity, may cause problems in oestrus detection and thus influence the reproductive efficiency. The aim of the study was to test whether a breed characterised by low pregnancy rate and high emotional reactivity (Thoroughbreds) differs in oestrous behaviour from a primitive breed with higher reproductive efficiency (Koniks). Additionally, the follicle size was examined to determine how it influences the intensity of oestrus and uterine ultrasonic image and whether the pregnancy rate differs in relation ...
