Topic:Kinetics
Kinetics in horses refers to the study of motion and the forces that produce or alter such motion in equine subjects. This area of research involves analyzing the movement patterns of horses to understand the mechanics of locomotion, including gait analysis, stride length, and joint angles. Kinetic studies often employ tools such as force plates and motion capture systems to quantify the forces exerted by and upon the horse during various activities. These studies provide insights into the efficiency and biomechanics of equine movement, contributing to fields such as veterinary medicine, sports science, and rehabilitation. This page compiles peer-reviewed research studies and scholarly articles that explore the principles, methodologies, and applications of kinetic analysis in horses.
Preserving frozen stallion sperm on dry ice using polymers that modulate ice crystalization kinetics. Cryopreserved semen is routinely shipped in liquid nitrogen. Dry ice could serve as an alternative coolant, however, frozen storage above liquid nitrogen temperatures (LN2, -196 °C) may negatively affect shelf-life and cryosurvival. In this study, we determined critical temperatures for storage of cryopreserved stallion sperm. We evaluated: (i) effects of cooling samples to different subzero temperatures (-10 °C to -80 °C) prior to storing in LN2, (ii) stability at different storage temperatures (i.e., in LN2, dry ice, -80 °C and -20 °C freezers, 5 °C refrigerator), and (iii) sperm...
Oxidative stress in donor mares for ovum pick-up delays embryonic development. The in vitro production of equine embryos via ovum pick-up (OPU) and intracytoplasmic sperm injection (ICSI) has increased rapidly. There is a marked effect of the individual mare on the outcome of OPU-ICSI, but little is known about the influence of the mare's health condition. This study aimed to investigate the potential associations between the concentrations of interleukin-6 (IL-6), reactive oxygen metabolites (d-ROMs), and biological antioxidant potential (BAP) in serum of oocytes' donor mares and the subsequent embryonic development. Just before OPU, a blood sample was collected from 28...
Kinetic, genomic, and physiological analysis reveals diversity in the ecological adaptation and metabolic potential of Brachybacterium equifaecis sp. nov. isolated from horse feces. Brachybacterium species have been identified in various ecological niches and belong to the family within the phylum . In this study, we isolated a novel JHP9 strain from horse feces and compared its kinetic, biochemical, and genomic features with those of other strains. Moreover, comparative genomic analysis using publicly available genomes was performed to determine the properties involved in their ecological adaptation and metabolic potential. Novel species delineation was determined phylogenetically through 16S rRNA gene similarity (up to 97.9%), average nucleotide identity (79.5-82.5%...
A novel kinetic energy harvesting system for lifetime deployments of wildlife trackers. Wildlife tracking devices are key in obtaining detailed insights on movement, animal migration, natal dispersal, home-ranges, resource use and group dynamics of free-roaming animals. Despite a wide use of such devices, tracking for entire lifetimes is still a considerable challenge for most animals, mainly due to technological limitations. Deploying battery powered wildlife tags on smaller animals is limited by the mass of the devices. Micro-sized devices with solar panels sometimes solve this challenge, however, nocturnal species or animals living under low light conditions render solar cells...
Analysis of the effect of 1-Allyl-3-Methylimidazolium chloride on thermodynamic stability, folding kinetics, and motional dynamics of horse cytochrome c. 1-allyl-3-methylimidazolium chloride (AMIMCl) acts as a potential green solvent for proteins. The present work provides a possible pathway by which the structural, kinetic, thermodynamic, and folding properties of horse cytochrome c (cyt c) are affected in green aqueous-AMIMCl systems. Analysis of the effect of AMIMCl on thermodynamic stability, refolding/unfolding kinetics, and motional dynamics of cyt c provided important information, (i) AMIMCl decreases the thermodynamic stability of reduced cyt c and also strengthens the guanidinium chloride (GdmCl)-mediated decrease in thermodynamic stab...
Continuous versus discrete data analysis for gait evaluation of horses with induced bilateral hindlimb lameness. Gait kinematics measured during equine gait analysis are typically evaluated by analysing (asymmetry-based) discrete variables (eg, peak values) obtained from continuous kinematic signals (eg, timeseries of datapoints). However, when used for the assessment of complex cases of lameness, such as bilateral lameness, discrete variable analysis might overlook relevant functional adaptations. Objective: The overall aim of this paper is to compare continuous and discrete data analysis techniques to evaluate kinematic gait adaptations to lameness. Methods: Method comparison. Methods: Sixteen healthy ...
Kinematic and kinetic analyses of the gait of horses wearing novel legwear for variably limiting extension of the metacarpophalangeal joint. To investigate the effects of novel legwear designed to limit metacarpophalangeal joint (MCPJ) extension and redirect loading forces from the flexor apparatus through analyses of 2-D kinematic and kinetic data. Methods: 6 adult horses without musculoskeletal disease. Methods: Horses were subjected to 4 treatments: control (no legwear), inactive legwear (unlimited legwear extension), and active legwear with mild (30°) and moderate (20°) legwear extension limitation. Two-dimensional kinematic data were collected for the right forelimb (FL) during walk and trot and from leading and trailing FLs...
Diclofenac Prodrugs for Intra-articular Depot Injectables: In Vitro Hydrolysis and Species Variation. Intra-articular depot injectables based on in situ suspension formation of ester prodrugs of nonsteroidal anti-inflammatory drugs are promising for management of joint pain. As candidates for this delivery approach, 5 diclofenac ester prodrugs comprising different imidazole-containing promoieties were synthesized and their physicochemical properties characterized. In vitro hydrolysis rates were investigated in buffer solutions, in 40% (v/v) human, equine, canine, and rat plasma, and in 80% (v/v) human and equine synovial fluid. Bioconversion of the prodrugs to diclofenac was found to be enzym...
Cryopreservation of stallion semen: laboratory assessment of sperm injuries after cushioned centrifugation and freezing with conventional and alternative directional freezing methods. Fresh 36 ejaculates of 13 stallions were split into two volumes, centrifuged with and without cushion and frozen with Conventional and two prototype, Drum and Directional, methods using 0.5 ml straws for the Conventional and Drum, and 2 ml flat straws for both the Drum and Directional. Cushioned centrifugation increased total motility (61.2 ± 18.6% vs. 57.5 ± 18.6%; P < 0.001) and mean velocity (84.3 ± 15.6% vs. 83.2 ± 13.8%; P < 0.05) when compared to not cushioned centrifugation, estimated after cooling the sperm at 4⁰C for 90 min before freezing. Cushioned centrifugation also in...
Chiral Selectivity in Inter-reactant Recognition and Electron Transfer of the Oxidation of Horse Heart Cytochrome c by Trioxalatocobaltate(III). Outer-sphere electron transfer (ET) between optically active transition-metal complexes and either other transition-metal complexes or metalloproteins is a prototype reaction for kinetic chirality. Chirality as the ratio between bimolecular rate constants of two enantiomers mostly amounts to 1.05-1.2 with either the Λ or Δ form the more reactive, but the origin of chirality in ET parameters such as work terms, electronic transmission coefficient, and nuclear reorganization free energy has not been addressed. We report a study of ET between the Λ-/Δ-[Co(Ox)3](3-) pair (Ox = oxalate) and hor...
Evidence for a Shared Mechanism in the Formation of Urea-Induced Kinetic and Equilibrium Intermediates of Horse Apomyoglobin from Ultrarapid Mixing Experiments. In this study, the equivalence of the kinetic mechanisms of the formation of urea-induced kinetic folding intermediates and non-native equilibrium states was investigated in apomyoglobin. Despite having similar structural properties, equilibrium and kinetic intermediates accumulate under different conditions and via different mechanisms, and it remains unknown whether their formation involves shared or distinct kinetic mechanisms. To investigate the potential mechanisms of formation, the refolding and unfolding kinetics of horse apomyoglobin were measured by continuous- and stopped-flow fluore...
Comparative analysis of cryoprotective agents influence on thermodynamic and kinetic parameters of equine and human hemoglobin molecules. Critical to the understanding the mechanism of destruction and protection during cryopreservation of biological objects is the knowledge of the conformational transitions of biopolymers experiencing low temperatures in the presence of cryoprotective agents. This information may be derived from the kinetic and thermodynamic parameters of macromolecular thermal denaturation kinetics under different environmental conditions. Objective: The study deals with the influence of cryoprotective agents (glycerol, 1.2-propanediol (1.2-PD), and dimethyl sulfoxide (DMSO)) on thermodynamic and kinetic parame...
Colloid centrifugation of fresh stallion semen before cryopreservation decreased microorganism load of frozen-thawed semen without affecting seminal kinetics. Freezability of equine semen may be influenced by microorganism population of semen. The objective of this study was to verify the effect of single-layer density gradient centrifugation (SLC) of fresh semen before cryopreservation on semen's microbial load (ML) and sperm cells kinetics after freezing-thawing. For that, one ejaculate was collected from 20 healthy stallions and split into control (C) samples (cryopreserved without previous SLC) and SLC samples (subjected to SLC). Semen cryopreservation was performed according to the same protocol in both groups. Microbial load of each microorgan...
Kinetics of the forelimb in horses circling on different ground surfaces at the trot. Circling increases the expression of distal forelimb lameness in the horse, depending on rein, diameter and surface properties of the circle. However, there is limited information about the kinetics of horses trotting on circles. The aim of this study was to quantify ground reaction force (GRF) and moments in the inside and outside forelimb of horses trotting on circles and to compare the results obtained on different ground surfaces. The right front hoof of six horses was equipped with a dynamometric horseshoe, allowing the measurement of 3-dimensional GRF, moments and trajectory of the centr...
Skin temperature during cutaneous wound healing in an equine model of cutaneous fibroproliferative disorder: kinetics and anatomic-site differences. To map skin temperature kinetics, and by extension skin blood flow throughout normal or abnormal repair of full-thickness cutaneous wounds created on the horse body and limb, using infrared thermography. Methods: Experimental. Methods: Standardbreds (n = 6), aged 3-4 years. Methods: Three cutaneous wounds were created on the dorsolateral surface of each metacarpus and on the lateral thoracic wall. Thoracic skin wounds and those on 1 randomly chosen forelimb healed by second intention without a bandage, whereas contralateral limb wounds were bandaged to induce formation of exuberant granulation...
Effect of an endurance-like exercise on the disposition and detection time of phenylbutazone and dexamethasone in the horse: application to medication control. Equine antidoping rules were established to prevent a horse's performance being altered after the administration of prohibited substances, including approved drugs used for legitimate treatment. Veterinarians have to advise owners or trainers on appropriate withholding times to guarantee that their horses may safely compete after drug administration. In order to propose tailored withdrawal times, several horse organisations released detection time (DT) values, for the main veterinary drugs used in horses. One of the possible limits to the information provided by published DTs in horses is the ...
Brief note about plasma catecholamines kinetics and submaximal exercise in untrained standardbreds. Four untrained standardbred horses performed a standardized exercise test on the treadmill and an automated blood collection system programmed to obtain blood samples every 15 s was used for blood collection in order to evaluate the kinetics of adrenaline and noradrenaline. The highest average values obtained for adrenaline and noradrenaline were 15.0 +/- 3.0 and 15.8 +/- 2.8 nmol/l respectively, with exponential accumulation of adrenaline (r = 0.977) and noradrenaline (r = 0.976) during the test. Analysis of the correlation between noradrenaline and adrenaline for each phase of the test shows...
Motions of the running horse and cheetah revisited: fundamental mechanics of the transverse and rotary gallop. Mammals use two distinct gallops referred to as the transverse (where landing and take-off are contralateral) and rotary (where landing and take-off are ipsilateral). These two gallops are used by a variety of mammals, but the transverse gallop is epitomized by the horse and the rotary gallop by the cheetah. In this paper, we argue that the fundamental difference between these gaits is determined by which set of limbs, fore or hind, initiates the transition of the centre of mass from a downward-forward to upward-forward trajectory that occurs between the main ballistic (non-contact) portions o...
Correlation of acid-induced conformational transition of ferricytochrome c with cyanide binding kinetics. A relation between pH-induced conformational transitions of horse heart ferricytochrome c and the kinetics of external ligand coordination to heme iron was investigated by optical spectroscopy, circular dichroism and viscometry. The dependencies of both the association, k (a), and dissociation rate constants of cyanide binding on pH were determined from kinetic measurements. The association rate constant exhibits a bell-shaped form of dependence on pH in the region where this protein unfolds. The maximum of the dependence of k (a) on pH is found to be coincident with the pK values of conformat...
Flow microcalorimetric study of butyrylcholinesterase kinetics and inhibition. The enzymatic hydrolysis of butyrylcholine, catalyzed by horse serum butyrylcholinesterase (EC 3.1.1.8), was studied at 37 degrees C in Tris buffer (pH 7.5) by flow microcalorimetry. A convolution procedure, using the Gamma distribution to represent the impulse response of the calorimeter, was developed to analyze the microcalorimetric curves. After correction for buffer protonation, the hydrolysis reaction was found to be slightly endothermic, with Delta H=+9.8 kJ mol(-1). Enzyme kinetics was studied with both the differential and integrated forms of the Michaelis equation with equivalent res...
The influence of the width of the saddle tree on the forces and the pressure distribution under the saddle. As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was d...
Comparison on plasma caesium kinetics in goats and horses with special emphasis on exercising horses. Like potassium (K+), caesium (Cs+) tends to concentrate intracellularly. The aim here was to determine how moderate exercise affects the uptake of Cs+ from blood plasma. Methods: After an intravenous Cs+ dose of 5 micromol kg(-1), plasma Cs+ concentration was followed for 100 min in goats and for 60 min in horses. The latter were divided into two groups, one resting and the other trotting on a treadmill (inclination 3 degrees, speed 5 m s(-1)). Results: The plasma Cs+ concentration follows a multiphase exponential decay curve, which initially could be approximated with a two-phase curve. The i...
Deprotonation of the horse liver alcohol dehydrogenase-NAD+ complex controls formation of the ternary complexes. Binding of NAD+ to wild-type horse liver alcohol dehydrogenase is strongly pH-dependent and is limited by a unimolecular step, which may be related to a conformational change of the enzyme-NAD+ complex. Deprotonation during binding of NAD+ and inhibitors that trap the enzyme-NAD+ complex was examined by transient kinetics with pH indicators, and formation of complexes was monitored by absorbance and protein fluorescence. Reactions with pyrazole and trifluoroethanol had biphasic proton release, whereas reaction with caprate showed proton release followed by proton uptake. Proton release (200-55...
Effect of induced unilateral synovitis of distal intertarsal and tarsometatarsal joints on sagittal plane kinematics and kinetics of trotting horses. To study the effect of unilateral synovitis in the distal intertarsal and tarsometatarsal joints on locomotion, including the compensating effects within and between limbs. Methods: 4 clinically normal horses. Methods: Gait analyses including kinematics, force plate, and inverse dynamic analysis were performed at the trot before lameness, after which synovitis was induced by injecting endotoxin into the right distal intertarsal and tarsometatarsal joints. Gait analyses were repeated 24 to 30 hours later during lameness. Differences between the stride variables during the 2 conditions (lame and...
Molecular modeling of manganese regulation of calmodulin-sensitive adenylyl cyclase from mammalian sperm. The soluble calmodulin-sensitive isoform of adenylyl cyclase isolated from equine sperm is unique because it requires Mn(2+) rather than Mg(2+) for activity. To gain insight into the molecular action of metals on sperm adenylyl cyclase, the kinetics of Mn(2+) and ATP effect was examined. A biphasic response to increases in ATP concentration was observed when metal was held constant. When [Mn(2+)] exceeded [ATP], however, greatly enhanced enzyme activity was observed. The kinetic profiles were consistent with allosteric activation of adenylyl cyclase by Mn(2+). Linear transformation of the data...
Species comparison of vitamin K1 2,3-epoxide reductase activity in vitro: kinetics and warfarin inhibition. A comparative study of vitamin K(1) 2,3-epoxide reductase (VKOR) activity in vitro was conducted across species. The apparent kinetic constants K(m app), V(max), and Cl(int app) were determined in bovine, canine, equine, human, murine, ovine, porcine, and rat hepatic microsomes. In addition to these enzyme kinetic constants, the IC(50) of warfarin for VKOR was determined in human, murine, porcine, and rat hepatic microsomes. Interspecies differences were observed when comparing the K(m app) (range, 2.41-6.46 microM), V(max) (range, 19.5-85.7 nmol/mg/min), and Cl(int app) (range, 8.2-18.4 ml/mg...
Effect of (auto)phosphorylation on the kinetic behavior of the Ca2+/calmodulin-dependent protein kinase II from horse brain. After extraction and purification, the kinetic behavior of the Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II) from horse brain was investigated as a function of ATP and a synthetic substrate, syntide-2. Both phospho- and dephospho- forms of the enzyme obey a bi-bi random mechanism. The K(M)s for ATP (K(M,ATP)) and syntide-2 (K(M,syntide-2)) were determined as equal to 80 and 30 microM, respectively. However, the maximum reaction yield is decreased by 50% when the enzyme is (auto)phosphorylated. In addition, this phosphorylated form of the enzyme leads to the formation of a total...
ATPase and Adpase activities in synovial membrane of equine metacarpophalangeal joint. ATPase and ADPase activities capable of hydrolyzing nucleoside di- and triphosphates in the presence of Ca2+ are present in synovial membrane of metacarpophalangeal joint mainly associated to membrane fractions. These hydrolytic activities have been considered involved in the inflammatory process where ATP and ADP are inflammatory mediators while adenosine counteracts this effect. Both, subcellular localization and kinetic properties of these nucleotidase activities, suggest that could correspond to single enzyme called ATP-diphosphohydrolase or apyrase. The comparison of the activity on ATP-C...
The effect of shoe material on the kinetics and kinematics of foot slip at impact on concrete. Previous studies on shoeing have demonstrated that shoe material alters the time taken from foot impact to the foot stopping sliding (slip time) and the distance slid. These are assumed to reflect differences in the craniocaudal ground reaction force (GRF) between the shoe and the ground during foot slip. This study tested the hypothesis that the slip time and distance are reflected in the resistance to slippage of the foot after impact. The forefeet of 8 horses were shod in horseshoes constructed of steel, plastic and rubber. Each horse was trotted for 8 placements per forefoot in each shoe t...
Histidin as a mercurial poisoning inhibitor. Histidin has been shown to effectively inhibit coagulation of horse oxyhemoglobin (HbO(2)) modified by mercury(II) ion bound to reactive thiol groups of protein. Kinetic parameters were measured and the histidin-to-mercury binding constant was kinetically estimated. Histidin, as other pharmaceutically acceptable compounds with some mercury-binding capacity, has been suggested to alleviate mercury intoxication conditions.