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.
Comparing Blind and Ultrasound-Guided Retrobulbar Nerve Blocks in Equine Cadavers: The Training Effect. In standing ophthalmic surgery in horses, a retrobulbar nerve block (RNB) is often placed blindly for anesthesia and akinesia. The ultrasound (US)-guided RNB may have fewer complications, but the two techniques have only been compared once in equine cadavers. This study compares the techniques for success and complication rates and analyzes the effect of training on US guidance. Twenty-two equine cadavers were divided into three groups: blind RNBs were performed bilaterally in eight cadavers, US-guided RNBs were performed bilaterally in seven cadavers, and after US-guided training, blind RNBs ...
Dominant follicle and gonadotropin dynamics before ovulation in postpartum lactating mares. The aim of this study was to compare the dominant follicle (DF) and gonadotropin dynamics for 9 days before ovulation in postpartum lactating (PP Lactating) versus non-postpartum cycling (N-PP Cycling) mares. Every PP Lactating mare on the day of parturition was paired with a N-PP Cycling mare, and the data analyses considered the partum-ovulation interval (POI) and the postpartum interovulatory interval (PPIOI) in PP Lactating mares and two interovulatory intervals in N-PP Cycling mares. The results of the present study revealed several novel and unique aspects of DF development and FSH and L...
Prevalence and treatment of gastric ulcers in Thoroughbred racehorses of Korea. Gastric ulcer is one of the prevalent diseases in racehorses. However, it has not been recognized as important in Korea, and drugs used to treat gastric ulcers are included in the doping test list, so they are not allowed to be administered to racehorses in training. Objective: This study was performed 1) to investigate the prevalence and the severity of gastric ulcers in Thoroughbred racehorses in Korea, 2) to confirm the therapeutic effect of ranitidine and omeprazole, and 3) to compare the efficacy between ranitidine and omeprazole. Methods: Forty-nine horses were randomly recruited, and ga...
Collagen and Microvascularization in Placentas From Young and Older Mares. In older mares, increasing collagen fibers (fibrosis) in the endometrium and oviduct predisposes to sub-fertility and infertility. In this study, (i) gene transcription of collagen (qPCR: COL1A1, COL1A2, COL3A1, COL5A1); (ii) total collagen protein (hydroxyproline); (iii) collagen distribution (Picrosirius red staining; polarized light microscopy); and (iv) microvascular density (Periodic acid-Schiff staining), were evaluated in mares' placenta, and related to mares age, and placenta and neonate weights. Samples were collected from the gravid horn, non-gravid horn, and body of the placenta fro...
Chemical composition and physical characteristics of faeces in horses with and without free faecal liquid – two case-control studies. Free faecal liquid (FFL) is a condition in horses characterised by two-phase (one solid and one liquid) separation of faeces. Causes of the condition are unknown, but disturbed hindgut fermentation has been suggested as it may alter biochemical composition and appearance of faeces in equines. However, information on faecal composition in horses with FFL is scarce. Faecal chemical composition (dry matter, osmolality, ash, macro minerals, short-chain fatty acids (SCFA) and pH) and physical characteristics (free liquid, sand, water holding capacity and particle size distribution) were compared in...
Comparison of Feed Digestibility between Ponies, Standardbreds and Andalusian Horses Fed Three Different Diets. Ponies and some horse breeds such as Andalusians exhibit an 'easy keeper' phenotype and tend to become obese more readily than other breeds such as Standardbreds. Various hypotheses have been proposed, including differences in appetite or metabolic efficiency. This study aimed to investigate the effect of breed on nutrient digestibility. Ponies, Standardbreds and Andalusian horses were adapted to consuming either a control fibre-based diet ( = 9), a hypercaloric cereal-rich diet ( = 12) or a hypercaloric fat-rich diet ( = 12) over 20 weeks. Total faecal collection was performed over 24 h to de...
Measurement of Plasma Resistin Concentrations in Horses with Metabolic and Inflammatory Disorders. Obesity and its associated complications, such as metabolic syndrome, are an increasing problem in both humans and horses in the developed world. The expression patterns of resistin differ considerably between species. In rodents, resistin is expressed by adipocytes and is related to obesity and ID. In humans, resistin is predominantly produced by inflammatory cells, and resistin concentrations do not reflect the degree of obesity, although they may predict cardiovascular outcomes. The aim of this study was to investigate the usefulness of resistin and its relationship with ID and selected ind...
Antibody Responses to a Reverse Genetics-Derived Bivalent Inactivated Equine Influenza Vaccine in Thoroughbred Horses. Updating vaccine strains is important to control equine influenza (EI). Previously, we reported that a monovalent inactivated EI vaccine derived from a virus generated by reverse genetics (RG) elicited immunogenicity in horses. In the present study, we compared antibody responses to a bivalent inactivated EI vaccine generated by RG and a commercially available bivalent inactivated EI (CO) vaccine derived from wild-type equine influenza viruses in Thoroughbred horses. The CO vaccine contained A/equine/Ibaraki/1/2007 (Florida sub-lineage clade 1) and A/equine/Yokohama/aq13/2010 (Florida sub-line...
Comparison of 2% mepivacaine and a solution of 2% lidocaine/epinephrine administered for median and ulnar nerve blocks in horses with naturally occurring forelimb lameness. To compare a 2% lidocaine solution containing 5 μg/ml (1:200 000) epinephrine with 2% mepivacaine for reducing lameness in horses after use in proximal nerve blocks. Methods: Experimental randomized crossover. Methods: Six adult horses with naturally occurring forelimb lameness. Methods: Horses were evaluated using an inertial gait sensor system. Lameness was measured as a vector sum (VS). Following baseline lameness examination, median and ulnar nerve blocks were performed with lidocaine/epinephrine (0.5 mg epinephrine added to 50 ml of 2% lidocaine immediately prior to administration)...
IIB or not IIB, part 2: assessing inter-rater and intra-rater repeatability of the Kenney-Doig scale in equine endometrial biopsy evaluation. Inter- and intra-rater variability negatively affects the reliability of various histopathology grading scales used as prognostic aids in human and veterinary medicine. The Kenney-Doig categorization (grading) scale, which is used to associate equine endometrial histologic lesions with prognostic estimation of a broodmare's reproductive potential, has not been evaluated for inter- or intra-rater variability, to our knowledge. To assess whether the Kenney-Doig system produces reliable results among observers, 8 pathologists, all with American College of Veterinary Pathologists certification, we...
The influence of the metacarpophalangeal joint angle on the transversal area and mean echogenicity of the superficial digital flexor tendon and suspensory ligament in gaited horses. The objective of this study was to assess the influence of the metacarpophalangeal (MCP) joint angle on the transversal area (TA) and mean echogenicity (ME) of the superficial digital flexor tendon (SDFT) and suspensory ligament (SL) in gaited horses. Ultrasound images were obtained from 50 healthy adult horses of the Mangalarga Marchador (MM; n=25) and Campeiro (n=25) breeds. Static and dynamic angles of the MCP joint were measured from photographs and video recordings. Higher ME values were evinced for the SL only in the group with the smaller dynamic angles of the MCP joint in the MM horses...
Effect of prostaglandin F2α administration on uterine polymorphonuclear neutrophil counts in Japanese heavy draft horses. The objective of this study was to examine the effect of prostaglandin F2α (dinoprost) and oxytocin administration on uterine polymorphonuclear neutrophil counts in the Japanese heavy draft mare. To compare polymorphonuclear neutrophil (PMN) counts in the endometrium, a total of 162 samples were collected from 54 estruses of 47 mares (before ovulation, day 0, and day 2) using a double-guarded cytology brush. Dinoprost (PG; 5 mg) was administered intramuscularly (i.m.) only once, on day 0, whereas oxytocin (OT; 20 U i.m.) was administered three times at 12-hr intervals starting on day 0. The p...
Average stride length and stride rate of Thoroughbreds and Quarter Horses during racing. The main factors influencing speed in athletes are stride length (SL) and stride rate (SR). However, conflict remains whether SL or SR is the key determinant of higher speeds. Quarter Horses (QH) generally reach higher speeds in their races than do Thoroughbreds (TB). However, the influence of SL and SR on this greater speed is unclear. Therefore, the main objective of this study was to compare SL and SR in QH and TB raced in short (sprint) and long (classic) distances. We hypothesized that QH have a higher SR in comparison to TB, and SR decreases as distance increases. Two race distances were...
Approaches to endocrinopathic laminitis in the field: Results of a survey of veterinary practitioners in North America. Endocrinopathic laminitis is the most common cause of laminitis in the field. Insulin has recently been implicated as a key factor in development of endocrinopathic laminitis; however, it is unclear whether diagnostic, and treatment approaches reflect insights derived from recent research. This study sought to evaluate North American veterinary practitioners' approach to endocrinopathic laminitis in the field. Demographic information, approach to diagnosis, management, and prognosis of endocrinopathic laminitis, as well as factors influencing changes in approach to laminitis were collected. To...
Cost of transport, but not gluteus medius and red blood cells monocarboxylate-transporters density differentiated Brazilian Sport Horses at two performance levels. Cost of transport (COT) and monocarboxylate transporters (MCTs) could affect the ability to perform fast actions during a jumping discipline. This study aimed to compare the COT and evaluate the MCT1, MCT4, and their auxiliary protein CD147 content in the gluteus medius and RBCs of Brazilian sport horses (BH), a breed developed for jumping competitions, with low-level (LL) or intermediate-level (IL) jumping capacities. The physiological difference between the horses was assessed by an incremental jump test (IJT), in which the cost of lactate (COT) and heart rate (COT) of running were determine...
Defining the specificity of recombinant human erythropoietin confirmation in equine samples by liquid chromatography-tandem mass spectrometry. The proteotypic human EPO peptides YLLEAK (T4), SLTTLLR (T11), TITADTFR (T14), and VYSNFLR (T17) are often used to confirm the presence of recombinant human EPO (rhEPO) in equine samples. Each of these peptides contains one or more isomeric leucine or isoleucine amino acids, raising the possibility that a simple leucine/isoleucine substitution could lead to a false identification when compared with a rhEPO reference standard. To examine this possibility variants of these four peptides were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). These studies indicate that confir...
Characterisation of the oral glucose and sugar tolerance tests and the enteroinsular axis response in healthy adult donkeys. Insulin dysregulation (ID) is diagnosed in horses and ponies using oral glucose (OGTT) and oral sugar (OSTT) tolerance tests. The enteroinsular axis plays a major role in postprandial glucose disposal and insulin response in horses, ponies and foals. The insulin and incretin response to oral carbohydrate challenges has not been characterised in donkeys. Objective: (a) To characterise OGTT and OSTT, and (b) to assess the plasma incretin response to OGTT and OSTT in healthy donkeys. Methods: In vivo experiments. Methods: Six healthy adult female Andalusian donkeys were challenged with OGTT (1 g...
Within-Breath Oscillatory Mechanics in Horses Affected by Severe Equine Asthma in Exacerbation and in Remission of the Disease. Oscillometry is a technique that measures the resistance (R) and the reactance (X) of the respiratory system. In humans, analysis of inspiratory and expiratory R and X allows to identify the presence of tidal expiratory flow limitation (EFLt). The aim of this study was to describe inspiratory and expiratory R and X measured by impulse oscillometry system (IOS) in horses with severe asthma (SEA) when in clinical remission ( = 7) or in exacerbation ( = 7) of the condition. Seven healthy, age-matched control horses were also studied. Data at 3, 5, and 7 Hz with coherence > 0.85 at 3 Hz and >...
Binary Horse herd optimization algorithm with crossover operators for feature selection. This paper proposes a binary version of Horse herd Optimization Algorithm (HOA) to tackle Feature Selection (FS) problems. This algorithm mimics the conduct of a pack of horses when they are trying to survive. To build a Binary version of HOA, or referred to as BHOA, twofold of adjustments were made: i) Three transfer functions, namely S-shape, V-shape and U-shape, are utilized to transform the continues domain into a binary one. Four configurations of each transfer function are also well studied to yield four alternatives. ii) Three crossover operators: one-point, two-point and uniform are al...
What can equine surveillance learn from surveillance of other species? Mary-Ellen Lloyd Tivey of the Royal Veterinary College, suggests that greater collaboration and encouraging engagement from horse owners and vets is key to strengthening scanning surveillance in equine populations.
Epigenetic models developed for plains zebras predict age in domestic horses and endangered equids. Effective conservation and management of threatened wildlife populations require an accurate assessment of age structure to estimate demographic trends and population viability. Epigenetic aging models are promising developments because they estimate individual age with high accuracy, accurately predict age in related species, and do not require invasive sampling or intensive long-term studies. Using blood and biopsy samples from known age plains zebras (Equus quagga), we model epigenetic aging using two approaches: the epigenetic clock (EC) and the epigenetic pacemaker (EPM). The plains zebra...
Pharmacokinetics of diphenhydramine following single-dose intravenous and oral administration in non-fasted adult horses. Diphenhydramine is an H1 receptor antagonist used to control urticaria and other allergic signs caused by type I hypersensitivity reactions in horses (Equus caballus). Limited studies have been conducted on pharmacokinetics of this drug in horses, with no studies involving oral formulations. Our study investigated pharmacokinetics of an oral diphenhydramine formulation compared to intravenous administration in non-fasted adult horses. Six healthy horses underwent a single administration of three different doses of diphenhydramine (1 mg/kg intravenously, 1 mg/kg intragastrically, and 5 mg/kg...
Impact of Gait and Diameter during Circular Exercise on Front Hoof Area, Vertical Force, and Pressure in Mature Horses. Circular exercise can be used at varying gaits and diameters to exercise horses, with repeated use anecdotally relating to increased lameness. This work sought to characterize mean area, mean vertical force, and mean pressure of the front hooves while exercising in a straight line at the walk and trot, and small (10-m diameter) and large circles (15-m diameter) at the walk, trot, and canter. Nine mature horses wore TekscanTM Hoof Sensors on their forelimbs adhered with a glue-on shoe. Statistical analysis was performed in SAS 9.4 with fixed effects of leg, gait, and exercise type (PROC GLIMMIX...
Comparison of Bone Mineral Content of the Equine Third Metacarpal to Total Radiographic Bone Aluminum Equivalents From Unprocessed Digital Radiographs. Digital radiographs are common for estimating bone mineral content (BMC) in horses with radiographic bone aluminum equivalents (RBAE). Processing algorithms are used to produce clearer images of digital radiographs in clinical settings, but this distorts RBAE. This study compared RBAE from digital radiographs to BMC from bone ash, and physical and digital morphology measurements. Digital radiographs were taken of six third metacarpals (MCIII) from equine cadavers with an aluminum step wedge penetrometer. A 2-cm transverse section of bone was digitally analyzed and excised from each MCIII. For ...
Obesity-Related Metabolic Dysfunction in Dairy Cows and Horses: Comparison to Human Metabolic Syndrome. Obesity has become a serious health problem with frequent occurrence both in human and animal populations. It is estimated that it may affect over 85% of the human population and 70-80% of horses and cows by 2030. Fat cow syndrome (FCS) is a combination of metabolic, digestive, infectious, and reproductive disorders that affects obese periparturient dairy cows, and occurs most frequently in loose-housing systems, where periparturient and dry cows are fed and managed in one group disregarding the lactation stages. Equine metabolic syndrome (EMS) was named after human metabolic syndrome (MetS) a...
Monitoring for the genetic structure of Mezen breed of horses in terms of DNA microsatellites. Mezenskaya horse (Mezenka) is Russia's aboriginal breed. It is a domestic selection in the northern territories of Arkhangelsk region. The breed is perfectly adapted to the conditions of the Far North, and has a number of valuable economic and biological qualities. At present, it has a limited gene pool and is bred only in the Mezensky district, where one gene pool-breeding farm is operating and so is a number of basic farms, where selection and breeding activities take place with the breed. Due to a small population of Mezen horses, the challenge of preserving its intra-breed diversity is ver...
Molecular characterization of equine thymidine kinase 1 and preliminary evaluation of its suitability as a serum biomarker for equine lymphoma. Thymidine kinase 1 (TK1) plays a key role in the synthesis of deoxythymidine triphosphate (dTTP) and is thus important for DNA replication and cell proliferation. The expression of TK1 is highest during S-phase, and it is rapidly degraded after mitosis. In cancer cells, TK1 is upregulated, resulting in leakage of excess TK1 into the blood. Consequently, serum TK1 has been used as a diagnostic and prognostic cancer biomarker, mainly in human medicine. The aims of this work were to characterize equine TK1 and to evaluate its suitability as a serum biomarker for equine lymphoma. Results: Equine T...
Scanning electron microscopy of the nasal skin in different animal species as a method for forensic identification. The current study aims to provide a new method for the identification of animal species by using the scanning electron microscopic study on the nasal skin around the nostril. The reference databases for animal identification using traditional ways (i.e., hair and bone analyses) were somewhat available. This study was conducted on the nasal skin of seven different animal species: large ruminants (Saidi buffalo and frozen Angus cattle); small ruminants (Egyptian goat and Rahmani sheep); camels (one-hump dromedary camel); equines (African domestic donkey and Arabian horse); carnivores (farm domes...
Robustness of five different visual assessment methods for the evaluation of hindlimb lameness based on tubera coxarum movement in horses at the trot on a straight line. The evaluation of hindlimb lameness remains a major challenge in everyday clinical practice. In the absence of clear guidelines, veterinarians use different visual assessment methods for this task whose robustness is unknown. Objective: Determination of the robustness of five visual hindlimb lameness assessment methods based on the comparison of left and right tuber coxae movement. Methods: Validated mathematical hindlimb lameness model based on experimental data from the literature. Methods: Vertical movement of left (LTC) and right (RTC) tuber coxae was simulated for the range of common hind...
Phenylbutazone pharmacokinetics in southern white rhinoceros (Ceratotherium simum simum) after oral administration. Southern white rhinoceros (Ceratotherium simum simum) frequently develop painful conditions, such as traumatic injuries or osteoarthritis, necessitating the administration of pain-relieving medications. One of the preferred treatments is the nonsteroidal anti-inflammatory drug phenylbutazone because of the availability of oral formulations and the familiarity of its use in horses. For the main study, a single oral dose of phenylbutazone at 2 mg/kg was administered to healthy adult rhinoceros (n = 33) housed at six North American zoological institutions. Each rhinoceros had up to four blood ...