Equine Science encompasses the study of horses and their management, health, and performance. This field integrates various scientific disciplines such as biology, genetics, nutrition, physiology, and veterinary medicine to understand and improve the well-being and capabilities of horses. Areas of focus include equine anatomy, reproduction, behavior, and disease prevention. Research in equine science aims to enhance horse care, optimize training and performance, and address health challenges. This page compiles peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine science, providing insights into the latest advancements and methodologies in the field.
Djernaes JD, Nielsen JV, Berg LC.The widths of spaces between the thoracolumbar processi spinosi (interspinous spaces) are frequently assessed using radiography in sports horses; however effects of varying X-ray beam angles and geometric distortion have not been previously described. The aim of this prospective, observational study was to determine whether X-ray beam angle has an effect on apparent widths of interspinous spaces. Thoracolumbar spine specimens were collected from six equine cadavers and left-right lateral radiographs and sagittal and dorsal reconstructed computed tomographic (CT) images were acquired. Sequentia...
Hiraga A, Sugano S.The history of research on the exercise physiology of racehorses in Japan dates back to the 1930s. A research report entitled "Studies on exercise physiology and performance testing of the racehorse", published in 1933 by Shigeo Matsuba and Torao Shimamura of The University of Tokyo, was epoch-making and the most important study in the history of equine exercise physiology in Japan. Research results were reported from 92 Thoroughbred racehorses in a large-scale project during the period of 1928 to 1932 at the Shimofusa Imperial Farm and the Koiwai Farm, which were the two greatest racehorse fa...
Azarpeykan S, Dittmer KE.Housekeeping genes (HKGs) are used as internal controls for normalising and calculating the relative expression of target genes in RT-qPCR experiments. There is no unique universal HKG and HKGs vary among organisms and tissues, so this study aimed to determine the most stably expressed HKGs in the equine kidney. The evaluated HKGs included 18S ribosomal RNA (18S), 28S ribosomal RNA (28S), ribosomal protein L32 (RPL32), β-2-microglobulin (B2M), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), succinate dehydrogenase complex (SDHA), zeta polypeptide (YWHAZ), and hypoxanthine phosphoribosyltran...
Almarzook S, Reissmann M, Brockmann GA.Arabian horse registries classify Arabian horses based on their dam lineages into five main strains. To test the maternal origin of Syrian Arabian horses, 192 horses representing the three major strains Saglawi, Kahlawi, and Hamdani were sequenced for 353 bp of their mitochondrial displacement loop (D-loop) region. Sequencing revealed 28 haplotypes comprising 38 sequence variations. The haplotype diversity values were 0.95, 0.91, and 0.90 in Kahlawi, Hamdani, and Saglawi strains, respectively. The pair-wise population differentiation estimates (Fst) between strains were low, ranging between 0...
Prieto JMB, Tallmadge RL, Felippe MJB.Identification and classification of B cell subpopulations has been shown to be challenging and inconsistent among different species. Our study tested aspects of ontogeny, phenotype, tissue distribution, and function of equine CD5 B cells, which represented a greater proportion of B cells early in development and in the peritoneal cavity. CD5 and CD5 B cells differentially expressed B cell markers (CD2, CD21, IgM) measured using flow cytometry, but similar mRNA expression of signature genes (DGKA, FGL2, PAX5, IGHM, IL10) measured using quantitative RT-PCR. Sequencing lambda light chain segment...
Hitchens PL, Hultgren J, Frössling J, Emanuelson U, Keeling LJ.Determining welfare status in a population is the first step in efforts to improve welfare. The primary objective of this study was to explore a new epidemiological approach for analysis of data from official competent authorities that pertain to compliance with animal welfare legislation. We reviewed data already routinely collected as part of Swedish official animal welfare inspections for 2010-13, using a checklist containing 45 checkpoints (CPs). These covered animal-, resource- and management-based measures of equine welfare. The animal-based CPs were measures that directly related to the...
Barton AK, Shety T, Bondzio A, Einspanier R, Gehlen H.Overexpression of matrix-metalloproteinases (MMPs) has been shown to lead to tissue damage in equine recurrent airway obstruction (RAO), as a misbalance with their natural inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), occurs. This favors irreversible pulmonary fibrosis formation. Increased levels of MMPs, TIMPs or altered ratios between them can be used as biomarkers of respiratory disease. We hypothesized that levels of MMPs, TIMPs and their ratios correlate with improvement in clinical findings and bronchoalveolar lavage fluid (BALF) cytology after 10 days of inhalative g...
Marycz K, Kornicka K, Grzesiak J, Śmieszek A, Szłapka J.Equine metabolic syndrome (EMS) is mainly characterized by insulin resistance, obesity, and local or systemic inflammation. That unfriendly environment of adipose tissue has huge impact on stem cells population (ASC) residing within. In the present study, using molecular biology techniques and multiple imaging techniques (SEM, FIB-SEM, and confocal microscopy), we evaluated the impact of EMS on ASC viability and chondrogenic differentiation. Moreover, we visualized the mitochondrial network and dynamics in ASC and ASC during control and chondrogenic conditions. In control conditions, ASC were ...
Sarkar S, Bailey E, Go YY, Cook RF, Kalbfleisch T, Eberth J, Chelvarajan RL, Shuck KM, Artiushin S, Timoney PJ, Balasuriya UB.Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory, systemic, and reproductive disease of horses and other equid species. Following natural infection, 10-70% of the infected stallions can become persistently infected and continue to shed EAV in their semen for periods ranging from several months to life. Recently, we reported that some stallions possess a subpopulation(s) of CD3+ T lymphocytes that are susceptible to in vitro EAV infection and that this phenotypic trait is associated with long-term carrier status following exposure to the virus. ...
Wutke S, Benecke N, Sandoval-Castellanos E, Döhle HJ, Friederich S, Gonzalez J, Hallsson JH, Hofreiter M, Lõugas L, Magnell O, Morales-Muniz A....Horses have been valued for their diversity of coat colour since prehistoric times; this is especially the case since their domestication in the Caspian steppe in ~3,500 BC. Although we can assume that human preferences were not constant, we have only anecdotal information about how domestic horses were influenced by humans. Our results from genotype analyses show a significant increase in spotted coats in early domestic horses (Copper Age to Iron Age). In contrast, medieval horses carried significantly fewer alleles for these phenotypes, whereas solid phenotypes (i.e., chestnut) became domina...
Okuda Y, Moe HH, Moe KK, Shimizu Y, Nishioka K, Shimogiri T, Mannen H, Kanemaki M, Kunieda T.Myanmar native horses are small horses used mainly for drafting carts or carriages in rural areas and packing loads in mountainy areas. In the present study, we investigated genotype distributions and allele frequencies of the LCORL/NCAPG, MSTN and DMRT3 genes, which are associated with body composition and locomotion traits of horses, in seven local populations of Myanmar native horses. The genotyping result of LCORL/NCAPG showed that allele frequencies of C allele associated with higher withers height ranged from 0.08 to 0.27, and 0.13 in average. For MSTN, allele frequencies of C allele ass...
Sandra O, Charpigny G, Galio L, Hue I.In mammalian species, endometrial receptivity is driven by maternal factors independently of embryo signals. When pregnancy initiates, paracrine secretions of the preattachment embryo are essential both for maternal recognition and endometrium preparation for implantation and for coordinating development of embryonic and extraembryonic tissues of the conceptus. This review mainly focuses on domestic large animal species. We first illustrate the major steps of preattachment embryo development, including elongation in bovine, ovine, porcine, and equine species. We next highlight conceptus secret...
Sevane N, Dunner S, Boado A, Cañon J.The Spanish Purebred horses, also known as Andalusian horses, compete to the highest standards in international dressage events. Gait and conformation could be used as early selection criteria to detect young horses with promising dressage ability. Although the genetic background of equine size variation has been recently uncovered, the genetic basis of horse conformational and locomotive traits is not known, hampered by the complex genetic architecture underlying quantitative traits and the lack of phenotypic data. The aim of this study was to validate the loci associated with size in 144 Spa...
Loscher DM, Meyer F, Kracht K, Nyakatura JA.Many ungulates show a conspicuous nodding motion of the head when walking. Until now, the functional significance of this behaviour remained unclear. Combining in vivo kinematics of quadrupedal mammals with a computer model, we show that the timing of vertical displacements of the head and neck is consistent with minimizing energy expenditure for carrying these body parts in an inverted pendulum walking gait. Varying the timing of head movements in the model resulted in increased metabolic cost estimate for carrying the head and neck of up to 63%. Oscillations of the head-neck unit result in w...
Clayton HM.In spite of having large height and body mass, horses are cursorial animals with an extensive gait repertoire and considerable athletic abilities. The limbs have evolved so that the heavy musculature is confined to the proximal limbs while the distal limbs are light in weight with a single functional digit and long, lightweight tendons to move and support the distal joints. These adaptations reduce the moment of inertia and decrease the energy expended to protract and retract the limbs during locomotion. There is a division of labor between the forelimbs, which have a pillar-like construction ...
Wilkens MR, Marholt L, Eigendorf N, Muscher-Banse AS, Feige K, Schröder B, Breves G, Cehak A.Intestinal calcium absorption plays a key role in the maintenance of calcium homeostasis and may either occur by paracellular or transcellular mechanisms. The horse has some unique peculiarities in calcium homeostasis compared to other species including a high absorptive capacity for calcium in the intestine, high plasma calcium concentrations, high renal excretion, and low plasma concentrations of vitamin D metabolites. So far, knowledge about the underlying mechanisms and the regulation of intestinal calcium absorption is still limited concerning this species. Several studies have documented...
Flethøj M, Kanters JK, Pedersen PJ, Haugaard MM, Carstensen H, Olsen LH, Buhl R.Although premature beats are a matter of concern in horses, the interpretation of equine ECG recordings is complicated by a lack of standardized analysis criteria and a limited knowledge of the normal beat-to-beat variation of equine cardiac rhythm. The purpose of this study was to determine the appropriate threshold levels of maximum acceptable deviation of RR intervals in equine ECG analysis, and to evaluate a novel two-step timing algorithm by quantifying the frequency of arrhythmias in a cohort of healthy adult endurance horses. Results: Beat-to-beat variation differed considerably with he...
Miller D, Tallmadge RL, Binns M, Zhu B, Mohamoud YA, Ahmed A, Brooks SA, Antczak DF.The polymorphism of major histocompatibility complex (MHC) class II DQ and DR genes in five common equine leukocyte antigen (ELA) haplotypes was determined through sequencing of mRNA transcripts isolated from lymphocytes of eight ELA homozygous horses. Ten expressed MHC class II genes were detected in horses of the ELA-A3 haplotype carried by the donor horses of the equine bacterial artificial chromosome (BAC) library and the reference genome sequence: four DR genes and six DQ genes. The other four ELA haplotypes contained at least eight expressed polymorphic MHC class II loci. Next generation...
Paillot R, Rash NL, Garrett D, Prowse-Davis L, Montesso F, Cullinane A, Lemaitre L, Thibault JC, Wittreck S, Dancer A.Vaccination is highly effective to prevent, control, and limit the impact of equine influenza (EI), a major respiratory disease of horses. However, EI vaccines should contain relevant equine influenza virus (EIV) strains for optimal protection. The OIE expert surveillance panel annually reviews EIV evolution and, since 2010, the use of Florida clade 1 and 2 sub-lineages representative vaccine strains is recommended. This report summarises the development process of a fully- updated recombinant canarypox-based EI vaccine in order to meet the last OIE recommendations, including the vaccine mode ...
Harris PA, Ellis AD, Fradinho MJ, Jansson A, Julliand V, Luthersson N, Santos AS, Vervuert I.The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the p...
Ringhofer M, Yamamoto S.Some domestic animals are thought to be skilled at social communication with humans due to the process of domestication. Horses, being in close relationship with humans, similar to dogs, might be skilled at communication with humans. Previous studies have indicated that they are sensitive to bodily signals and the attentional state of humans; however, there are few studies that investigate communication with humans and responses to the knowledge state of humans. Our first question was whether and how horses send signals to their potentially helpful but ignorant caretakers in a problem-solving ...
Tamura N, Kuroda T, Kotoyori Y, Fukuda K, Nukada T, Kato T, Kuwano A, Kasashima Y.Sonoelastography can assess the inner stiffness of tissues. Sonoelastographic evaluation of injured equine superficial digital flexor tendons (SDFTs) is considered to be useful for assessing the stiffness of a lesion even during late-stage rehabilitation. The purpose of this study was to investigate and compare the sonoelastographic appearance of injured SDFTs over time from the onset of the injury. Eighteen horses were classified into three groups according to the length of time from injury onset: group A, within two weeks after injury; group B, approximately five months after injury; and gro...
Woo PC, Teng JL, Bai R, Wong AY, Martelli P, Hui SW, Tsang AK, Lau CC, Ahmed SS, Yip CC, Choi GK, Li KS, Lam CS, Lau SK, Yuen KY.In a molecular epidemiology study using 791 fecal samples collected from different terrestrial and marine mammals in Hong Kong, genogroup I picobirnaviruses (PBVs) were positive by RT-PCR targeting the partial RdRp gene in specimens from five cattle, six monkeys, 17 horses, nine pigs, one rabbit, one dog, and 12 California sea lions, with 11, 9, 23, 17, 1, 1, and 15 sequence types in the positive specimens from the corresponding animals, respectively. Phylogenetic analysis showed that the PBV sequences from each kind of animal were widely distributed in the whole tree with high diversity, shar...
de Winter NJ, Snoeck C, Claeys P.The study of stable isotopes in fossil bioapatite has yielded useful results and has shown that bioapatites are able to faithfully record paleo-environmental and paleo-climatic parameters from archeological to geological timescales. In an effort to establish new proxies for the study of bioapatites, intra-tooth records of enamel carbonate stable isotope ratios from a modern horse are compared with trace element profiles measured using laboratory micro X-Ray Fluorescence scanning. Using known patterns of tooth eruption and the relationship between stable oxygen isotopes and local temperature se...
Holcomb KE, Stull CL, Kass PH.Closure of US equine slaughter facilities in 2007 along with the concomitant economic recession have contributed to a sharp increase in the number of unwanted horses throughout the United States, with estimates totaling 100,000 horses per year. The objective of the study was to obtain comprehensive data regarding nonprofit organizations caring for unwanted horses, along with the characteristics and outcome of horses relinquished to these organizations. Nonprofit organizations that accept relinquished equines were contacted to participate in a 90-question survey. Responding organizations (144 o...
The protein journalJanuary 18, 2023
Volume 42, Issue 1 24-36 doi: 10.1007/s10930-023-10092-x
Rodríguez MC, Mussio PE, Villarraza J, Tardivo MB, Antuña S, Fontana D, Ceaglio N, Prieto C.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...
Jardat P, Ringhofer M, Yamamoto S, Gouyet C, Degrande R, Parias C, Reigner F, Calandreau L, Lansade L.Recently, research on domestic mammals' sociocognitive skills toward humans has been prolific, allowing us to better understand the human-animal relationship. For example, horses have been shown to distinguish human beings on the basis of photographs and voices and to have cross-modal mental representations of individual humans and human emotions. This leads to questions such as the extent to which horses can differentiate human attributes such as age. Here, we tested whether horses discriminate human adults from children. In a cross-modal paradigm, we presented 31 female horses with two simul...
Tait AD, Hodge LC, Allen WR.The production of equilin and the other ring B-unsaturated estrogens by the pregnant mare is anomalous in that they are biosynthesised by a cholesterol-independent pathway. Fetal horse gonads were incubated with tritiated sodium acetate and radiochemically pure 3 beta-hydroxy-5,7-pregnadien-20-one and 3 beta-hydroxy-5,7-androstadien-17-one were isolated. A fetal gonad--placental system is proposed for equilin production, 3 beta-hydroxy-5,7-pregnadien-20-one being a precursor for 3 beta-hydroxy-5,7-androstadien-17-one in the fetal gonad and the latter being the precursor of equilin in the place...
Moyo NA, Marchi E, Steinbach F.Dendritic cells (DC) are the main immune mediators inducing primary immune responses. DC generated from monocytes (MoDC) are a model system to study the biology of DC in vitro, as they represent inflammatory DC in vivo. Previous studies on the generation of MoDC in horses indicated that there was no distinct difference between immature and mature DC and that the expression profile was distinctly different from humans, where CD206 is expressed on immature MoDC whereas CD83 is expressed on mature MoDC. Here we describe the kinetics of equine MoDC differentiation and activation, analysing both ph...
Thway TM, Clay CM, Maher JK, Reed DK, McDowell KJ, Antczak DF, Eckert RL, Nilson JH, Wolfe MW.Immortalized cell lines have many potential experimental applications including the analysis of molecular mechanisms underlying cell-specific gene expression. We have utilized a recombinant retrovirus encoding the simian virus-40 (SV-40) large T antigen to construct several immortalized cell lines of equine chorionic girdle cell lineage - the progenitor cells that differentiate into the equine chorionic gonadotropin (eCG) producing endometrial cups. Morphologically, the immortalized cell lines appear similar to normal chorionic girdle cells. Derivation of the immortalized cell lines from a cho...
Sharma AK, Rajashankar KR, Yadav MP, Singh TP.The structure of mare apolactoferrin (MALT) has been determined at 3. 8 A resolution by the molecular-replacement method, using the structure of mare diferric lactoferrin (MDLT) as the search model. The MDLT structure contains two iron-binding sites: one in the N-terminal lobe, lying between domains N1 and N2, and one in the C-terminal lobe between domains C1 and C2. Both lobes have a closed structure. MALT was crystallized using the microdialysis method with 10%(v/v) ethanol in 0.01 M Tris-HCl. The structure has been refined to a final R factor of 0.20 for all data to 3.8 A resolution. Compar...
Serrano AL, Rivero JL.Fourteen 4-year old Andalusian mares were used to examine the plasticity of myosin heavy chain (MHC) composition in horse skeletal muscle with heavy draught-exercise training and detraining. Seven horses underwent a training programme based on carriage exercises for 8 months. Afterwards, they were kept in paddocks for 3 months. The remaining seven animals were used as control horses. Three gluteus medius muscle biopsies were removed at depths of 20, 40 and 60 mm from each horse before (month 0), during the training (months 3 and 8) and after detraining (month 11). Myosin heavy chain compositio...
Dell'Aquila ME, Cho YS, Minoia P, Traina V, Fusco S, Lacalandra GM, Maritato F.Conventional IVF as well as several assisted microfertilization techniques have shown limited success in the horse. After recent positive results achieved with intracytoplasmic injection of a single spermatozoon (ICSI) in human IVF, we chose to try the method in the horse. We compared conventional IVF to ICSI by fertilization rates of oocytes with compact and expanded cumuli and by developmental potential of the resulting embryos. Cumulus-oocyte complexes (COCs) were obtained by aspirating the follicular fluid from the ovaries of slaughtered mares. Complexes showing complete cumulus investment...
Johnson L.Seasonal variation in number of spermatogonia and germ cell degeneration was evaluated to determine which mechanism might explain seasonal differences in daily sperm production per testis (DSP/testis) or per g parenchyma (DSP/g) in stallions. Comparing 28 adult stallions (4 to 20 yr old) in each of the nonbreeding (December-January) and breeding (June-July) seasons, the population of type A spermatogonia was more than two times greater (P less than 0.01) in the breeding season. While the number of type B spermatogonia also was elevated (P less than 0.01) in the breeding season, the number of t...
Nauwelaerts S, Allen WA, Lane JM, Clayton HM.Quantifying the dynamics of limb movements requires knowledge of the mass distribution between and within limb segments. We measured segment masses, positions of segmental center of mass and moments of inertia of the fore and hind limb segments for 38 horses of different breeds and sizes. After disarticulation by dissections, segments were weighed and the position of the center of mass was determined by suspension. Moment of inertia was measured using a trifilar pendulum. We found that mass distribution does not change with size for animals under 600 kg and report ratios of segmental masses to...
Lindgren G, Naboulsi R, Frey R, Solé M.Equine skin diseases are common, causing increased costs and reduced welfare of affected horses.Genetic testing, if available, can complement early detection, disease diagnosis, and clinical treatment and offers horse breeders the possibility to rule out carrier status. The mechanisms of complex disease can be investigated by using the latest state-of-the-art genomic technologies. Genome-based strategies may also serve as an efficient and cost-effective strategy for the management of the disease severity levels, with particular interest in complex traits such as insect bite hypersensitivity, c...
Brown-Douglas CG, Firth EC, Parkinson TJ, Fennessy PF.There is little information on age, weight and time of year of puberty in Thoroughbred horses, and the interpretation of such data is difficult due to the wide variety of descriptions of the onset of puberty. Objective: To examine the age, bodyweight and date of onset of puberty in Thoroughbreds born in spring and autumn. Methods: Bodyweight data and blood samples were collected in 59 pasture-raised Thoroughbred horses. Five autumn-born and 18 spring-born colts and 3 autumn-born and 33 spring-born fillies were examined from birth to age 13 and 17 months. A testosterone concentration >2 s.d. ab...
Morrice-West AV, Hitchens PL, Walmsley EA, Tasker K, Lim SL, Smith AD, Whitton RC.Fatigue life (FL) is the number of cycles of load sustained by a material before failure, and is dependent on the load magnitude. For athletes, 'cycles' translates to number of strides, with load proportional to speed. To improve previous investigations estimating workload from distance, we used speed (m/s, x) per stride collected using 5 Hz GPS/800 Hz accelerometer sensors as a proxy for limb load to investigate factors associated with FL in a Thoroughbred race start model over 25,234 race starts, using a combination of mathematical and regression modelling. Fore-limb vertical force (NKg) w...
Liu XX, Pan JF, Zhao QJ, He XH, Pu YB, Han JL, Ma YH, Jiang L.The X chromosome shows a special interaction between demographic factors and genetic variation, and the analysis of X-linked genomic variation can therefore provide insights into the unique effects of demography and selection on the horse genome that cannot be readily detected by autosomal markers. Debao (DB) ponies have experienced intense selective pressure for the development of their small stature (<106 cm at adult height). To identify selective sweeps on the X chromosome of the DB pony, we performed a genome-wide scan of three Chinese horse breeds using an Equine SNP70 BeadChip. Using Yi...
Du J, Wang X, Ma J, Wang J, Qin Y, Zhu C, Liu F, Shao Y, Zhou J, Qiao W, Liu X.The equine infectious anemia virus (EIAV) is a lentivirus of the Retrovirus family, which causes persistent infection in horses often characterized by recurrent episodes of high fever. It has a similar morphology and life cycle to the human immunodeficiency virus (HIV). Its transmembrane glycoprotein, gp45 (analogous to gp41 in HIV), mediates membrane fusion during the infection. However, the post-fusion conformation of EIAV gp45 has not yet been determined. EIAV is the first member of the lentiviruses for which an effective vaccine has been successfully developed. The attenuated vaccine strai...
Nevins M, Nevins ML, Karimbux N, Kim SW, Schupbach P, Kim DM.The objective of this study is to evaluate the potential for periodontal regeneration of a critical-sized defect with the application of recombinant human platelet-derived growth factor (rhPDGF-BB) combined with either a particulate equine or a β-tricalcium phosphate (β-TCP) matrix. Methods: Critical-sized intrabony 2-wall defects were created bilaterally on the distal surface of the second premolar and the mesial surface of the first molar in nine hounds. Twelve defects received rhPDGF-BB/equine treatment, 12 defects received rhPDGF-BB/β-TCP treatment, and the remaining 12 sites served as ...
Esteves Trindade PH, de Camargo Ferraz G, Pereira Lima ML, Negrão JA, Paranhos da Costa MJR.This study aimed to investigate the use of maximum eye surface temperature (EST), recorded by infrared thermography, as an indicator of physical fitness in ranch horses. Data collection was carried out with 16 horses by recording six physical fitness biomarkers (EST, respiratory rate, creatine kinase activity [CK], and concentrations of total serum protein, plasmatic cortisol, and lactate) before and after a regular working day. We also recorded heart rate during the exercise, exercise duration, average velocity, distance traveled, and air temperature and humidity. The variation between the sa...
Nugent GE, Law AW, Wong EG, Temple MM, Bae WC, Chen AC, Kawcak CE, Sah RL.Determine (1) the site-associated response of articular cartilage of the equine distal metacarpal condyle to training at a young age as assessed by changes in indentation stiffness and alterations in cartilage structure and composition, and (2) relationships between indentation stiffness and indices of cartilage structure and composition. Methods: Experimental animals (n=6) were trained on a track (increasing exercise to 1km/day by 5 months); controls (n=6) were pasture-reared. Animals were euthanized at 18 months and four osteochondral samples were harvested per metacarpal condyle from dorsal...
Schlupp A, Anielski P, Thieme D, Müller RK, Meyer H, Ellendorff F.The beta2-agonist clenbuterol is commonly administered for therapeutic purposes in the horse, but its use an an anabolic agent is illegal. Clenbuterol can be detected in blood and urine for a relatively short period after administration and detection in hair could enhance the analytical range and be used to determine the history of clenbuterol application. Objective: That detection in mane or tail hair is possible over an extended period. Methods: Four horses received 0.8 microg clenbuterol hydrochloride/kg bwt b.i.d. for 10 days. Four other horses were used as untreated controls. Blood, urine...
Green JA, Xie S, Szafranska B, Gan X, Newman AG, McDowell K, Roberts RM.The pregnancy-associated glycoproteins (PAGs) are placental antigens that were initially characterized as pregnancy markers in the maternal circulation of domestic ruminant species. They are members of the aspartic proteinase gene family, having greatest sequence identity with pepsinogens. However, some are not capable of functioning as enzymes. The PAGs are associated with a large gene family within the Artiodactyla order (cattle, camels, pigs). So far, no members of this family have been characterized in species outside this order. This report describes the cloning and initial characterizati...
Echigoya Y, Sato T, Itou T, Endo H, Sakai T.The species-specific properties of LDH isozymes are essentially determined by M (muscle) and H (heart) subunit proteins encoded by the LDHA and LDHB genes, respectively. In the present study, we molecularly characterized the full-length equine lactate dehydrogenase A (eLDHA) and B (eLDHB) cDNAs. The eLDHA cDNA consisted of a 999-bp open reading frame (ORF), while the eLDHB and newly acquired bat LDHB consisted of a 1002-bp ORF, which is 3 bp shorter than the LDHB ORF of other registered mammals. The alignment of amino acid sequences showed that eLDHA acquired positively charged His 88 and 226,...
Stout TA.Situations in which suppression or stimulation of reproductive activity in stallions has been attempted, or is desired, include resolution of the equine arteritis virus 'shedding' state, induction of testicular descent in inguinal cryptorchids, and the improvement of sperm production capacity and/or semen quality in sub-fertile stallions. However, the most common reason for wanting to modulate reproductive activity in a stallion is to alter the expression of sexual behaviour. In the case of intact stallions used for competitive or recreational purposes, the overt expression of sexual or aggres...
Lisboa BRF, da Silva JAR, da Silva WC, Barbosa AVC, Silva LKX, Lourenço-Júnior JB.In Brazil, the study on equine thermoregulation has not shown considerable advances, moreover, in the Amazon, this is a little explored aspect. This study aims to evaluate the thermoregulation of horses submitted to two methods of post-exercise cooling, in the climatic conditions of the Eastern Amazon. The experiment was conducted at Centro Hipico, Ananindeua, Para, for 15 days. Ten male horses, castrated of the Brazilian breed, aged 13 years and with an average weight of 482.3 kg were used. Equestrianism, which was exercised with pre-established protocol in the arena and track, for 30 min. Af...
Gastal GD, Alves BG, Alves KA, Souza ME, Vieira AD, Varela AS, Figueiredo JR, Feugang JM, Lucia T, Gastal EL.The method of transportation and the conditions imposed on the ovarian tissue are pivotal aspects for the success of ovarian tissue cryopreservation (OTC). The aim of this study was to evaluate the effect of the size of the ovarian tissue (e.g. whole ovary, biopsy size and transplant size) during different times of storage (0, 6, 12 and 24 h) on the structural integrity of equine ovarian tissue transported at 4°C. Eighteen pairs of ovaries from young mares (<10 years old) were harvested in a slaughterhouse and processed to simulate the fragment sizes (biopsy and transplant size groups) o...
Sleutjens J, Smiet E, van Weeren R, van der Kolk J, Back W, Wijnberg ID.To evaluate the effect of various head and neck positions on intrathoracic pressure and arterial oxygenation during exercise in horses. Methods: 7 healthy Dutch Warmblood riding horses. Methods: The horses were evaluated with the head and neck in the following predefined positions: position 1, free and unrestrained; position 2, neck raised with the bridge of the nose aligned vertically; position 4, neck lowered and extremely flexed with the nose pointing toward the pectoral muscles; position 5, neck raised and extended with the bridge of the nose in front of a vertical line perpendicular to th...
Demyda-Peyrás S, Bottrel M, Acha D, Ortiz I, Hidalgo M, Carrasco JJ, Gómez-Arrones V, Gósalvez J, Dorado J.The aim of this study was to evaluate the effect of different cooling rates on post-thaw quality of cryopreserved donkey spermatozoa. Eighteen ejaculates from six adult Andalusian donkeys (three ejaculates per donkey) were collected using an artificial vagina. Pooled semen samples (two ejaculates per pool) were divided into three aliquots, and frozen in Gent freezing extender using three different cryopreservation protocols (P): P1 (conventional slow freezing, as control): semen pre-cooled in an Equitainer for 2 h and frozen in liquid nitrogen (LN) vapour; P2 (controlled pre-freeze cooling r...
Herd RP, Miller TB, Gabel AA.The effectiveness of 1 pro-benzimidazole (pro-BZD) drug, 3 benzimidazole (BZD) drugs, and 3 non-benzimidazole (non-BZD) drugs in keeping fecal egg counts below 50 eggs per gram 2 and 4 weeks after treatment at 6-week intervals was compared in groups of brood mares and yearlings at 2 Standardbred farms. In a preliminary study (December 1978 to April 1979) as well as major study (April to November 1979), horses were kept in the same groups in the same areas. In the major study, treatments were arranged in a Latin square design. On farm 1, which had a history of repeated use of BZD drug since 196...
Guerin MV, Deed JR, Kennaway DJ, Matthews CD.Plasma melatonin was measured at the winter and summer solstices and the autumn and spring equinoxes in four mares held under natural conditions at 35 degrees S. At all seasons the onset of the nightly elevated melatonin was coincident with or after the time of sunset and the melatonin offset after the time of sunrise. The duration of elevated melatonin was not different from the duration of natural scotophase for each season, with the duration of elevated melatonin longer in winter than the other seasons. Immediately following each 24 hr sampling two mares were resampled in acutely extended d...
Leemans B, Gadella BM, Stout TA, Nelis H, Hoogewijs M, Van Soom A.Induction of hyperactivated motility is considered essential for triggering the release of oviduct-bound mammalian spermatozoa in preparation for fertilization. In this study, oviduct-bound stallion spermatozoa were exposed for 2 h to: i) pre-ovulatory and ii) post-ovulatory oviductal fluid; iii) 100% and iv) 10% follicular fluid (FF); v) cumulus cells, vi) mature equine oocytes, vii) capacitating and viii) non-capacitating medium. None of these triggered sperm release or hyperactivated motility. Interestingly, native FF was detrimental to sperm viability, an effect that was negated by heat in...
