Topic:Biochemistry
The study of biochemistry in horses encompasses the chemical processes and substances that occur within equine organisms. This field investigates the molecular interactions and pathways that are fundamental to horse physiology, including metabolism, enzyme activity, and genetic expression. Key areas of interest include the examination of metabolic disorders, nutrient absorption, and the biochemical basis of muscle function and energy production. Researchers utilize biochemical analysis to understand health and disease mechanisms in horses, contributing to the development of diagnostic tools and therapeutic strategies. This page gathers peer-reviewed studies and scholarly articles that explore various biochemical processes and their implications for equine health and performance.
Sample stability and heparin interference in ionized calcium and ionized magnesium measurements in horses using the Stat Profile Prime Plus co-oximetry electrolyte analyzer. The determination of iCa and iMg is important in veterinary medicine, but their immediate determination in whole blood is not always possible. Their stability in other sample types and the existence of interferences must be evaluated before its use. Objective: We aimed to analyze the effects of storage time on the stability of iCa, iMg, and other analytes in whole blood, plasma, and serum samples in horses and assess the interference of heparin in these measurements. Methods: Whole blood, heparin-plasma, and serum samples from 10 horses were stored at 4°C and analyzed 1, 2, 3, 4, 5, 6, 7, 8, ...
High-Resolution Fluoro-Respirometry of Equine Skeletal Muscle. Mitochondrial function-oxidative phosphorylation and the generation of reactive oxygen species-is critical in both health and disease. Thus, measuring mitochondrial function is fundamental in biomedical research. Skeletal muscle is a robust source of mitochondria, particularly in animals with a very high aerobic capacity, such as horses, making them ideal subjects for studying mitochondrial physiology. This article demonstrates the use of high-resolution respirometry with concurrent fluorometry, with freshly harvested skeletal muscle mitochondria, to quantify the capacity to oxidize substrates...
Correlation between sphingomyelin and the membrane stability of mammalian erythrocytes. Lipid compositions of mammalian erythrocyte membranes are different among species. Therefore, the information on hemolysis from mammalian erythrocytes is useful to understand membrane properties of human erythrocytes. In this work, pressure-induced hemolysis and hypotonic one were examined using erythrocytes of human, sheep, cow, cat, dog, pig, horse, rat, and mouse. Pressure-induced hemolysis was suppressed by membrane sphingomyelin, whereas hypotonic hemolysis decreased upon increment of cell diameter. Mass spectra of erythrocyte membrane lipids demonstrated that sphingomyelin with an acyl c...
Plasma Creatine Kinase and Aspartate Aminotransferase Activities Before, During, and After 5 Days of Intramuscular Penicillin Administration in Sedentary Horses. Muscle damage can result in leakage of intracellular enzymes such as creatine kinase (CK) and aspartate transaminase (AST) into plasma. There are no controlled documentations of the effects of intramuscular antibiotic drug administration on plasma CK and AST activities in horses. The objective of this experiment was to test the hypothesis that 5 days of intramuscular procaine penicillin G injection in normal horses would result in increased plasma activities of CK and AST. Nine healthy adult horses were sampled for 7 days preceding, 5 days during, and 32 days following procaine penicillin G (2...
Novel Organoruthenium(II) Complex C1 Selectively Inhibits Butyrylcholinesterase without Side Effects on Neuromuscular Transmission. Enzyme butyrylcholinesterase (BChE) shows increased activity in some brain regions after progression of Alzheimer's disease and is therefore one of the therapeutic targets for symptomatic treatment of this neurodegenerative disorder. The organoruthenium(II) complex [(η--cymene)Ru(II)(1-hydroxy-3-methoxypyridine-2(1)-thionato)pta]PF () was designed based on the results of our previous structure-activity studies. Inhibitory activity toward cholinesterase enzymes shows that this complex selectively, competitively, and reversibly inhibits horse serum BChE (hsBChE) with an IC value of 2.88 µM. Wh...
Molecular docking and experimental validation of the effect of ergothioneine on heat shock protein-70 following endurance exercise by Arabian stallions. Exercise-induced oxidative stress is a challenge in equine sports. This study aims at determining the effects of ergothioneine on heat shock protein-70 (HSP-70) following the stress of an endurance exercise of 30 km by Arabian stallions. Molecular docking was also done to investigate the interaction between the ligand ergothioneine and heat shock protein-70 using sulfogalactosylceramide and sulfogalactoglycerolipid as standards. The study involved a total of 18 clinically healthy stallions, with an average age of 6.7 ± 2.4 years and an average weight of 411.54 ± 12.46 kg. Only cli...
Horse manure as resource for biogas and nanolignocellulosic fibres. Nanofibrillated cellulose (NFC) has key applications in composites, water filters and as emulsifiers. The affinity of NFC to water is a challenge, as it negatively influences its integrity. Lignin, a major component of plant biomass, is a natural hydrophobiser. Anaerobic digestion (AD) of biomass to produce biomethane allows to up-concentrate lignin in the fermentation residue containing lignocellulosic fibres. Horse manure was used as substrate for biogas production from which nanolignocellulose fibres (LCNF) were extracted. A biogas yield of 207 L kg with a methane concentration of 65 % was...
Cortisol Variations to Estimate the Physiological Stress Response in Horses at a Traditional Equestrian Event. In many countries, horses remain involved in traditional equestrian events such as those celebrated in Menorca (Balearic Islands, Spain) every year since at least the 14th century. The present study aimed to evaluate the variations in salivary cortisol concentrations to estimate the physiological stress response in horses at the Menorca patronal festivals. Two different editions (years 2016 and 2018) of the festivals in honor of the Virgin of Grace in Maó (Menorca, Spain) were studied. Nineteen and seventeen Pure Breed Menorca stallions were included in the study, respectively. The stallions ...
Effect of time and autologous serum addition on the analysis of cerebrospinal fluid in horses. Cerebrospinal fluid (CSF) is highly labile and delayed processing might alter results of analysis. Objective: To determine the effects of time and addition of autologous serum on cytological evaluation of CSF. Methods: Ten client-owned adult horses requiring euthanasia. Methods: Prospective study. Serum and CSF were collected from each horse before and within 10 minutes after euthanasia. CSF samples were divided into 15 aliquots (2 mL each); 1 aliquot was submitted for routine CSF analysis within 60 minutes of collection. Four drops of autologous serum were added to 7 of the aliquots, and ...
Impact of Coenzyme Q10 Supplementation on Skeletal Muscle Respiration, Antioxidants, and the Muscle Proteome in Thoroughbred Horses. Coenzyme Q10 (CoQ10) is an essential component of the mitochondrial electron transfer system and a potent antioxidant. The impact of CoQ10 supplementation on mitochondrial capacities and the muscle proteome is largely unknown. This study determined the effect of CoQ10 supplementation on muscle CoQ10 concentrations, antioxidant balance, the proteome, and mitochondrial respiratory capacities. In a randomized cross-over design, six Thoroughbred horses received 1600 mg/d CoQ10 or no supplement (control) for 30-d periods separated by a 60-d washout. Muscle samples were taken at the end of each peri...
Characterization of Myeloperoxidase in the Healthy Equine Endometrium. Myeloperoxidase (MPO), as a marker of neutrophil activation, has been associated with equine endometritis. However, in absence of inflammation, MPO is constantly detected in the uterine lumen of estrous mares. The aim of this study was to characterize MPO in the uterus of mares under physiological conditions as a first step to better understand the role of this enzyme in equine reproduction. Total and active MPO concentrations were determined, by ELISA and SIEFED assay, respectively, in low-volume lavages from mares in estrus ( = 26), diestrus ( = 18) and anestrus ( = 8) in absence of endometr...
Physicochemical Characterization of a Recombinant eCG and Comparative Studies with PMSG Commercial Preparations. Equine chorionic gonadotropin (eCG) is a glycoprotein hormone widely used in timed artificial ovulation (TAI) and superovulation protocols to improve the reproductive performance in livestock. Until recently, the only eCG products available in the market for veterinary use consisted in partially purified preparations of pregnant mare serum gonadotropin (PMSG). Here, a bioactive recombinant eCG (reCG) produced in suspension CHO-K1 cells was purified employing different chromatographic methods (hydrophobic interaction chromatography and reverse-phase (RP)-HPLC) and compared with a RP-HPLC-purifi...
Short Communication: Identification of equine corticotropin-like intermediate lobe peptide (CLIP) binding to an adrenocortipcotrophic hormone (ACTH) assay capture antibody. A chemiluminescent immunoassay is commonly employed to measure adrenocorticotrophic hormone (ACTH) concentrations to assist pituitary pars intermedia dysfunction diagnosis. In a previous study, seasonally-dependent assay cross-reactivity to endogenous equine corticotropin-like intermediate lobe peptide (CLIP, ACTH 18-39) was suspected. The present study aimed to demonstrate binding of endogenous equine CLIP to the capture antibody of the ACTH chemiluminescent immunoassay. Liquid chromatography - mass spectrometry (LCMS) methods were optimised to identify selected ions from synthetic human ACTH...
A Combination of Taurine and Caffeine in Stallion Semen Extender Positively Affects the Spermatozoa Parameters. This study was aimed to determine the impact of different taurine and caffeine combinations on the motility, viability, and oxidative markers of chilled stallion spermatozoa. Each stallion semen sample was diluted in a ratio of 1:2, with various taurine and caffeine concentrations (2.5-7.5 mg/mL taurine + 0.625-1.25 mg/mL caffeine) dissolved in a conventional extender. The control samples (CON) were prepared by diluting ejaculate only using the conventional extender. The motility was analyzed using a CASA system at different time intervals (0, 6, 12, 24, and 30 h) and the viability was evaluat...
Understanding the microbial fibre degrading communities & processes in the equine gut. The equine gastrointestinal tract is a self-sufficient fermentation system, housing a complex microbial consortium that acts synergistically and independently to break down complex lignocellulolytic material that enters the equine gut. Despite being strict herbivores, equids such as horses and zebras lack the diversity of enzymes needed to completely break down plant tissue, instead relying on their resident microbes to carry out fibrolysis to yield vital energy sources such as short chain fatty acids. The bulk of equine digestion occurs in the large intestine, where digesta is fermented for 3...
The Influence of Exercise Intensity on Tryptophan Metabolites in Thoroughbred Horses. Catabolism of tryptophan (Trp) is modulated by physical activity and provides a pool of active compounds: Trp is considered a calmative agent, kynurenine (Kyn) and 3-hydroxykynurenine (3-HKyn) show neurotoxic effects, kynurenic acid (Kyna) and xanthurenic acid (XA) have neuroprotective properties like nicotinamide (NAm), while serotonin is the neurotransmitter. The study was conducted to investigate the dependence of exercise intensity, measured by plasma lactic acid (LA) concentration, on the level of Trp, its catabolites (serotonin, Kyn, 3-HKyn, Kyna and XA), and NAm in Thoroughbred horses. ...
Evaluation of an Oral Supplemental Cannabidiol Product for Acceptability and Performance in Mature Horses. Thirty stock type geldings (15 ± 3 years; 556 ± 63 kg BW) were used in a randomized complete design over 28 days to determine the influence of cannabidiol (CBD) oil supplementation levels on body weight, body condition, and blood chemistry. Horses were randomly assigned to one of three dietary treatments (n = 10 per treatment) formulated with canola oil to provide 1.50 mg CBD/kg BW (TRTA), 0.75 mg CBD/kg BW (TRTB), or 0.00 mg CBD/kg BW (canola oil; CTRL). Treatments were top-dressed onto concentrate and individually administered twice daily. Horses were maintained in adjacent dry lots and re...
Ultrasonographic & biochemical analysis of thyroid bio-architecture for further pharmacological intervention in adult Arabian stallions & mares. Based on the growing attention to the Arabian horses with a lack of records regarding their normal physiological parameters, which are critically vital for disease diagnosis &convenient drug administration, we give great attention to their thyroid gland normalcy. The thyroid gland is one of the key players in regulating many physiological processes. Therefore, we tackled thyroid biology & morphology in 14 Arabian stallions & 18 Arabian mares from the beginning of March to the middle of April on animals from 4 to 19 years old. First, the blood samples taken from their jugular vein ...
Behavioral and hormonal assessment of stress in foals (Equus caballus) throughout the weaning process. This study had the aim to demonstrate the midterm effects (three weeks) of weaning on foals' welfare. For this purpose, foals' behavioral changes and fecal levels metabolites of cortisol were evaluated. The observations took place at the state stud farm of Baden-Wuerttemberg in Germany. Ten foals (six colts and four fillies) were observed from one day before weaning up until three weeks after weaning. Weaning was divided into three blocks, the first in September, the second in October, and the last in November. The behavioral observation was done during an eight-hour period between 7:00 a.m. a...
The Autophagy Marker LC3 Is Processed during the Sperm Capacitation and the Acrosome Reaction and Translocates to the Acrosome Where It Colocalizes with the Acrosomal Membranes in Horse Spermatozoa. Despite its importance in somatic cells and during spermatogenesis, little is known about the role that autophagy may play in ejaculated spermatozoa. Our aim was to investigate whether the molecular components of autophagy, such as microtubule-associated protein 1 light chain 3 (LC3), are activated in stallion spermatozoa during the capacitation and acrosome reaction and if this activation could modulate these biological processes. To analyze the autophagy turnover, LC3I and LC3II proteins were assessed by western blotting, and the ratio between both proteins (LC3II/LC3I) was calculated. In so...
Proteomic Differences Between the Ovulatory and Anovulatory Sides of the Mare’s Follicular and Oviduct Fluid. The follicular fluid and oviduct fluid play major roles in oocyte maturation, sperm activation, and fertilization. To better understand the physiological environments for equine oocyte maturation and fertilization, here we conducted the proteome analysis and comparison on follicular fluids and oviduct fluids from the ovulatory side and the anovulatory side. The results showed that there is no significant difference between two side oviduct fluids, but a total of 71 differential abundance proteins (DAPs) were identified between two side follicular fluids, of which 9 are up-regulated and 62 are ...
Galectinology of Equine Pregnancy. Galectins are a family of proteins that bind to glycans, acting in a cytokine-like manner throughout the body. In the majority of mammalians, galectins have been found to be involved in pregnancy maintenance, but few studies have evaluated this in the horse. Therefore, the objective of this study was to examine the expression of various galectins in pregnant and nonpregnant mares. Next-generation RNA sequencing was performed on the chorioallantois and endometrium of healthy pregnant mares at 120, 180, 300, and 330 days of gestation (n = 4/stage), as well as 45-day chorioallantois (n = 4), post...
Hematological and Biochemical Responses of Donkeys (Equus asinus) to Packing and Trekking During the Hot-Dry Season. The study aimed to evaluate effects of packing (load-carrying) and trekking on hematological and biochemical parameters in donkeys during the hot-dry season. Ten pack donkeys, aged 2-3 years, weighing 93 ± 2.7 kg were enrolled in the study and randomly divided into two groups of five animals each. Group 1 donkeys were subjected to packing + trekking while group 2 trekked only. All the donkeys trekked 20 km thrice, 1-day apart. Blood was collected before and after packing or trekking for hematological evaluation; and serum analyzed for electrolyte concentrations, and aspartate aminotransfera...
Comparison of an Antioxidant Source and Antioxidant Plus BCAA on Athletic Performance and Post Exercise Recovery of Horses. Antioxidant supplementation decreases postexercise oxidative stress but could also decrease muscle protein synthesis. This study compared the effects of three diets: low antioxidant (control, CON), high antioxidant (AO), and branched-chain amino acid high antioxidant (BCAO) supplementation on postexercise protein synthesis and oxidative stress. We hypothesized that supplementing antioxidants with branched-chain amino acids(BCAA) would reduce oxidative stress without hindering muscle protein synthesis. Eighteen mixed-breed polo horses (11 mares and 7 geldings, with age range between 5 and 18 ye...
Plasma Non-targeted Metabolomics Analysis of Yili Horses Raced on Tracks With Different Surface Hardness. In this study, the plasma non-targeted metabolomics of Yili horses were characterized before and after exercise on tracks that differed in surface hardness to better understand exercise-related biochemical changes. Blood samples were obtained from eight trained Yili horses before and immediately after exercise. Samples were used for metabolomic analysis by ultra-performance liquid chromatography-Q-EXACTIVE mass spectrometry. In total, 938 significantly different metabolites involving sugar, lipid, and amino acid metabolism were detected in the plasma, with significant increases in glucose, glu...
Pharmacokinetics of single dose administration of three increasing doses of acetaminophen per os in 1-3-month-old foals. Acetaminophen is a common analgesic and antipyretic drug used in human medicine and might be an alternative to nonsteroidal anti-inflammatory drugs for treating pain and pyrexia in foals. The pharmacokinetics and safety of differing doses of acetaminophen have not been investigated in foals. Objective: To determine the plasma pharmacokinetics and any changes in haematology and biochemistry profiles following oral administration of single doses of acetaminophen at 10, 20, and 40 mg/kg to foals. Methods: Randomised cross-over pharmacokinetic study. Methods: Six Quarter Horse (two colts and fou...
Binding of Equine Seminal Lactoferrin/Superoxide Dismutase (SOD-3) Complex Is Biased towards Dead Spermatozoa. Sperm-neutrophil binding is an important facet of breeding and significantly impacts fertility. While a specific seminal plasma protein has been found to reduce this binding and improve fertility (CRISP-3), additional molecule(s) appear to promote binding between defective sperm and neutrophils. Recent work has suggested one of these proteins is lactoferrin (LF), an 80 kDa iron-binding protein found throughout the body, but the purity of the protein was not confirmed. It is unknown if LF binds to sperm selectively based on viability, and if receptors for LF are located on equine sperm. To eval...
Follicle Selection in Mares as a Model for Illustrating the Many Hormonal and Biochemical Interactions That Drive a Single Physiological Mechanism. The mechanism for selection of the future dominant or ovulatory follicle in mares involves a relatively abrupt separation in growth rates between the future dominant follicle and several subordinate follicles and is termed diameter deviation. The event is used to illustrate that a coordinated complex of many follicular, hormonal, and biochemical factors interact and interbalance during a single physiological mechanism. For example, a positive effect of follicle stimulating hormone (FSH) on development of all follicles during the growing phase can later involve a positive effect of luteinizing ...
Molecularly imprinted polymers as effective capturing receptors in a pseudo-ELISA immunoassay for procalcitonin detection in veterinary species. In this study, a new sandwich-type immunoenzymatic assay, based on a molecularly imprinted polymer (MIP) as an artificial antibody (pseudo-ELISA), was developed for the determination of procalcitonin (PCT) in veterinary species. The quantification of PCT in human medicine represents the state of the art for the diagnosis of sepsis; instead the clinical studies on the relevance of PCT as a sepsis predictor in veterinary patients are few, likely due to the total absence of validated assays. MIPs have been widely used as antibody mimics for important applications, and MIP-based sandwich assays ha...
The Lipidomics of Spermatozoa and Red Blood Cells Membrane Profile of Martina Franca Donkey: Preliminary Evaluation. Fatty acid-based lipidomic analysis has been widely used to evaluate health status in human medicine as well as in the veterinary field. In equine species, there has been a developing interest in fertility and sperm quality. Fatty acids, being the principal components of the membranes, play an active role in the regulation of the metabolic activities, and their role on spermiogenesis seems to be of great importance for the resulting quality of the sperm and, thus, fertility. With the application of widely used lipidomic techniques, the aim of this study was to evaluate: (a) the fatty acid cont...