The physiology of horses encompasses the study of the biological functions and processes that occur within the equine body. This includes the examination of various systems such as the cardiovascular, respiratory, musculoskeletal, digestive, and nervous systems. Understanding equine physiology is essential for comprehending how horses adapt to different environmental conditions, perform physical activities, and respond to health challenges. Research in this field often focuses on the mechanisms of energy metabolism, thermoregulation, and muscle function during exercise, as well as the physiological responses to stress and disease. This page compiles peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine physiology, providing insights into the biological processes that support the health and performance of horses.
The aim of this study was to compare the effect of three sugars and Equex paste in a freezing extender for donkey sperm cryopreservation. Ejaculates (n = 18) were collected from six Andalusian donkeys of proven fertility were pooled (two ejaculates per pool) and cryopreserved using a freezing extender containing three different sugars (glucose, fructose and sorbitol), with or without the addition of Equex paste. Sperm quality was assessed before and after freezing-thawing for motility, morphology, plasma membrane integrity, acrosome integrity and DNA integrity. The use of sorbitol in the f...
Luethy D, Johnson AL, Stefanovski D, Boston RC, Orsini JA.Equine metabolic syndrome (EMS) is prevalent in the equine population, and somatostatin analogs might be useful for diagnosis and/or treatment of EMS in horses. The purpose of this study was to evaluate the glucose and insulin responses to subcutaneous and intravenous administration of somatostatin. Six healthy research horses were included in this prospective study. An initial pilot study was performed to assess several different doses (10-22 µg/kg [4.5-10 µg/lb]) in two horses, then a final dosage of 22 µg/kg (10 µg/lb) was administered to six horses IV and SQ in a two-period random...
Banse HE, Getachew F, Levy M, Smits J.Hair cortisol has been demonstrated to reflect hypothalamic-pituitary-adrenal axis activity (including Cushing's disease and stress) in several species. We hypothesized that hair cortisol concentrations are increased in horses with pituitary pars intermedia dysfunction (PPID) compared with healthy adult horses and that this difference is magnified in the fall, when circulating adrenocorticotropin (ACTH) is generally the highest. Cortisol from hair collected using clippers with a #40 blade from the neck was compared between PPID horses and control horses over several months in the fall (August-...
Melchert M, Aurich C, Aurich J, Gautier C, Nagel C.Stress at foaling has been demonstrated to delay birth. In this study, we followed the hypothesis that even a short delay of foaling increases catecholamine and cortisol release in foals, induces acidosis and impairs neonatal adaptation. Foaling was prolonged for 5 min by transferring mares to an unfamiliar environment at rupture of the allantochorion (group delay, n = 6) while control mares (n = 5) were left undisturbed. In their foals, times from birth to first standing and first suckling, heart rate, heart rate variability (HRV) and salivary cortisol concentration were analysed. B...
Kämpf S, Seiler E, Bujok J, Hofmann-Lehmann R, Riond B, Makhro A, Bogdanova A.Detection of hematopoietic activity in horses is a challenge due to the lack of cells carrying reticulocyte markers such as RNA remnants or CD71 in the circulation. In this study, we fractionated equine red cells according to their density and analyzed the cells forming low (L), medium (M), and high (H) density fractions for markers of aging such as membrane loss, oxidation, and alterations in the intracellular free Ca levels. Cells forming L and M fraction were highly heterogeneous in projected areas and shapes, and had higher propensity to swell in response to hypo-osmotic challenge than the...
Windberger U, Auer R, Seltenhammer M, Mach G, Skidmore JA.From a certain level of exercise-intensity onward, hematocrit increases in horses, which brings more oxygen carriers into the bloodstream. Camels, however, when used in competitive racing could be even in need of iron supplementation and blood transfusions due to a severe reduction of their available hematocrit compared to their resting hematocrit. Since the extrinsic and intrinsic mechanical properties of camel erythrocytes (RBC) are so different compared to RBCs of other mammals, the question arises whether this observation might be a response to endurance exercise aiming at keeping the RBC ...
Walter J, Huwiler F, Fortes C, Grossmann J, Roschitzki B, Hu J, Naegeli H, Laczko E, Bleul U.Maturation of oocytes under in vitro conditions (IVM) results in impaired developmental competence compared to oocytes matured in vivo. As oocytes are closely coupled to their cumulus complex, elucidating aberrations in cumulus metabolism in vitro is important to bridge the gap towards more physiological maturation conditions. The aim of this study was to analyze the equine "cumulome" in a novel combination of proteomic (nano-HPLC MS/MS) and metabolomic (UPLC-nanoESI-MS) profiling of single cumulus complexes of metaphase II oocytes matured either in vivo (n = 8) or in vitro (n = 7). Re...
Bardell D, Mosing M, Cripps PJ.Arterial hypoxaemia is common in anaesthetised horses, but little information exists regarding restoration of arterial oxygen tension (PaO ) during recovery from anaesthesia, or if intra-operative management factors exert any longer-term effect. Objective: To evaluate PaO in horses recovering from general anaesthesia up to 1 h after resuming standing. Methods: Prospective observational clinical cohort study. Methods: Systemically healthy adult horses undergoing inhalational general anaesthesia for elective surgical procedures were studied. Arterial blood samples were obtained anaerobically pr...
Best R, Standing R.Global positioning systems (GPS) have recently been shown to reliably quantify the spatiotemporal characteristics of Polo, with the physiological demands of Polo play at low- and high-goal levels also investigated. This study aims to describe the spatiotemporal demands of Polo across 0-24 goal levels. A player-worn GPS unit was used to quantify distance, speed and high-intensity activities performed. Data were divided into chukkas and five equine-based speed zones, grouped per cumulative player handicap and assessed using standardized mean differences. Average distance and speed per chukka inc...
Heales CJ, Summers IR, Fulford J, Knapp KM, Winlove CP.The aetiology of bone marrow oedema-like abnormalities (BMOA) seen on magnetic resonance imaging (MRI) is as yet not fully understood. The current study aimed to investigate the potential of projection radiography and Raman microspectroscopy to provide information regarding the underlying physiological changes associated with BMOA in equine bone samples. Methods: MRI was used to assess 65 limbs from 43 horses. A subset of 13 limbs provided 25 samples, 8 with BMOA present and 17 as controls; these were examined with projection radiography to assess bone mineral density and Raman spectroscopy to...
Manso-Díaz G, García-López JM, López-Sanromán J, Taeymans O.To provide a comprehensive anatomical description of the normal equine nasolacrimal duct using magnetic resonance imaging, and to develop a practical protocol for performing magnetic resonance dacryocystography (MRD) in horses. Methods: The heads of ten fresh horse cadavers with no history of sinonasal or ophthalmologic disorders were used for this study. Methods: An MRD technique was developed in this study, which consisted of two parts. In the first part, olive oil and gadolinium were compared as contrast medium, using five horses. Two concentrations of gadolinium were used: 0.25 mmol/mL an...
van Dorland A, Janett F, Bruckmaier R, Wach-Gygax L, Jeannerat E, Bollwein H, Sieme H, Burger D.Effects of a plasmolysed yeast product enriched with herbs, malt, honey and orange syrup on semen characteristics and oxidative status in stallions were evaluated. Twenty stallions (mean age ± standard deviation = 9.5 ± 4.5 years) were randomly divided into a treatment group (n = 10) receiving 0.06 mL/kg bodyweight of plasmolysed herbal yeast, and a control group (n = 10) receiving the same amount of placebo daily in the feed for 10 weeks. Ejaculates were collected weekly from all stallions starting at Week 0. Volume, sperm concentration, motility, and velocity were eva...
Greco-Otto P, Léguillette R.Horses competing in pulling competitions often undergo rapid weight change to enter lower weight categories. The aim of this study was to assess weight change and the associated changes of body water compartments in pulling horses. Weight change was attributed primarily to body water losses; however, losses from other sources were also indicated. . Les chevaux participant à des compétitions de trait subissent souvent des changements de poids rapides pour s’inscrire à des catégories de poids inférieurs. Le but de cette étude consistait à évaluer le changement de poids et les changemen...
Trösch M, Ringhofer M, Yamamoto S, Lemarchand J, Parias C, Lormant F, Lansade L.Inferring what others witnessed provides important benefits in social contexts, but evidence remains scarce in nonhuman animals. We investigated this ability in domestic horses by testing whether they could discriminate between two experimenters who differed in what they previously witnessed and decide whom to solicit when confronted with an unreachable food source based on that information. First, horses saw food being hidden in a closed bucket (impossible for them to open) in the presence of two experimenters who behaved identically but differed in their attention to the baiting process (the...
Kay G, Tligui N, Semmate N, Azrib R, González FJN, Brizgys L, McLean A.Serum amyloid A (SAA) is an acute phase protein and α-globulin that is produced in the liver in response to inflammatory cytokines. Considered a major acute phase protein in most domestic species, its concentrations rapidly decrease after resolution of inflammation, making SAA measurement a useful tool for monitoring the course of inflammation in an individual animal. The objective of this study was to compare SAA values in working equids including mules, donkeys and horses as well as values for different diseases at various times of the year. Samples were collected from 77 equids; 13 mules, ...
Knych HK, Baden RW, Gretler SR, McKemie DS.Despite their widespread popularity as sport and companion animals and published and anecdotal reports of vast difference in drug disposition and pharmacokinetics between individuals, studies describing equine drug metabolism are limited. It has been theorized that similar to humans, members of the CYP2D family in horses may be polymorphic in nature leading to differences in metabolism of substrates. This study aims to build on the limited current knowledge regarding P450 mediated metabolism in horses by describing the metabolism of the polymorphic CYP2D6 probe drug codeine in vitro. Codeine, ...
Gehlen H, Schlaga A.Several studies have shown the effect of training on myocardial deformation parameters in human athletes. The aim of this prospective, longitudinal study was echocardiographic evaluation of myocardial velocities and deformation in horses during the first year of training. Twelve Standardbred yearlings were examined using tissue Doppler imaging (TDI) and two-dimensional speckle tracking (2D-ST) during the first year of race training (short axis of left and right ventricle). The first examination was performed before the beginning of training (n = 12). At the last time point, horses were fully ...
Gulmez C, Atakisi O.It was aimed to investigate the effects of kumiss a fermented mare horse beverage on the sirtuin deacetylases in the oxidative stress which had been induced by 1,2-dimethyl hydrazine (DMH). Forty BALB/C male mice were divided into four groups as control, kumiss (2 × 10 cfu/mL), DMH (20 mg/kg), and kumiss + DMH (2 × 10 cfu/mL + 20 mg/kg). At the end of 20-week regimen, SIRT2, SIRT3 protein expressions by western blotting, immunolocalizations, and inhibitory anti-oxidant activity analysis in liver, colon, and kidney tissues were performed. SIRT2 and SIRT3 expressions in DMH g...
Sales FA, Ferreira-Silva JC, Vieira JI, Chaves MS, Caldas EL, Filho JP, Freitas VJ, Oliveira MA.Addition of extenders to thawed semen could improve fertility. Objective: To determine the efficiency of extenders to increase viability of thawed semen, measured by sperm parameters in vitro and pregnancy rates after artificial insemination (AI). Methods: Sperm motility and acrosin activity were measured during a thermoresistance test (TRT). Results: Progressive motility decreased (P<0.05) after 30 min in thawing semen treated with saline solution (SS) and only after 60 min with Tyrode's solution (TS) or freezing diluent (FD). The total motility decreased (P<0.05) after 60 min in thawed semen...
Mampe JR, Tatarniuk DM, Suarez-Fuentes DG, Kraus KH. The aim of this study was to to determine the comparative stiffness following repair of an axial sagittal fracture model in equine distal sesamoid bones using either a single 3.5-mm or 4.5-mm cortical bone screw placed in lag fashion. Methods: The present study was an biomechanical study. Results: The mean (±standard deviation) stiffness value for the 4.5-mm screw-bone construct (522.49 N/mm ± 168.21) was significantly greater than the 3.5-mm screw-bone construct (408.46 N/mm ± 131.13) ( = 0.047). This represents a 28% difference in mean stiffness. Conclusions: ...
Liu X, Zhang Y, Li Y, Pan J, Wang D, Chen W, Zheng Z, He X, Zhao Q, Pu Y, Guan W, Han J, Orlando L, Ma Y, Jiang L.High altitude represents some of the most extreme environments worldwide. The genetic changes underlying adaptation to such environments have been recently identified in multiple animals but remain unknown in horses. Here, we sequence the complete genome of 138 domestic horses encompassing a whole altitudinal range across China to uncover the genetic basis for adaptation to high-altitude hypoxia. Our genome data set includes 65 lowland animals across ten Chinese native breeds, 61 horses living at least 3,300 m above sea level across seven locations along Qinghai-Tibetan Plateau, as well as 7...
Canola PA, Valadão CAA, Canola JC, Flôres FN, Lopes MCS.The objective of this study was to evaluate clinical and cardiovascular parameters and pleural and intra-abdominal pressures of horses after experimentally induced unilateral open pneumothorax. Prospective, experimental study-animals: seven healthy adult horses, 4 females and 3 males. Left hemithorax thoracotomy was carried out to create an open pneumothorax for 60 minutes. Pleural pressure (P) was directly obtained at the midpoint of the left eighth intercostal space before thoracotomy. Esophageal pressure (P), arterial blood gas analysis, left ventricular function, and ultrasonographic asses...
Della Malva A, De Palo P, Lorenzo JM, Maggiolino A, Albenzio M, Marino R.The aim of this study was to evaluate the effect of post-mortem aging on tenderness development and proteolysis of myofibrillar proteins in 3 different horse muscles. Warner-Bratzler shear force decreased during aging in all muscles, showing the lowest values in longissimus lumborum (LL) in all sampling points. Myofibril fragmentation index significantly increased in LL and semimembranosus (SM) muscles throughout aging time whereas in semitendinosus (ST) it increased after 14 days of aging. Proteomics analysis revealed the major content of intact myofibrillar proteins with high molecular wei...
Kandemir H, Dukik K, Hagen F, Ilkit M, Gräser Y, de Hoog GS.The anthropophilic dermatophyte Trichophyton tonsurans and its zoophilic counterpart T. equinum are phylogenetically closely related. The barcoding marker rDNA internal transcribed spacer (ITS) shows limited variation between these two species. In the current study, we combined molecular approaches with phenotypic data to determine the species boundaries between T. tonsurans (n = 52) and T. equinum (n = 15) strains originating from humans (n = 40), horses (n = 26), and a mouse (n = 1). Culture characteristics and physiology on Trichophyton agar media 1 and 5 were evaluated....
Hernández-Avilés C, Love CC, Serafini R, Teague SR, Varner DD.Commonly marketed semen extenders contain various antibiotic types and concentrations to control bacterial growth from stallion's external genitalia. An experiment was conducted to test the effects of supplemental amikacin disulfate (1,000 μg/mL) + potassium penicillin G (1,000 IU/ML: INRA-AP), or ticarcillin-clavulanate (1,000 μg/mL: INRA-TIM) in the INRA 96 extender, on sperm function and antimicrobial activity, compared with extender without supplemental antibiotics (INRA-C). In freshly extended semen (Time 30m), no differences were observed among the three treatment groups for sperm m...
Mogielnicka-Brzozowska M, Fraser L, Dziekońska A, Gackowska K, Sobiewska M, Kuzborska A, Majewska AM, Filipowicz K, Kordan W.The aim of this study was to identify the proteoforms of albumin and kallikrein in stallion seminal plasma (SP), and to determine their correlations with sperm motility parameters. The experimental material consisted of ejaculates from 8 stallions, which were collected during the breeding and non-breeding seasons (BS and NBS, respectively). SP proteins were identified by 2-D PAGE and mass spectrometry (MALDI TOT/TOF MS). Sperm motility parameters were analyzed using the CASA system. Protein expression (integrated optical density-IOD) of albumin proteoforms 1 (ALB 1) and 2 (ALB 2) and kallikrei...
Moeller S, Patan-Zugaj B, Däullary T, Tichy A, Licka TF.Laminitis is associated with failure of the suspensory apparatus of the distal phalanx (SADP) connecting the distal phalanx to the hoof wall. The specific aim of this study was to examine in vitro whether thinning of the hoof wall leading to increased deformability influences the damage of the laminar tissue created by loading of the hoof. Paired cadaver forelimbs from twelve horses were used. For each pair, the hoof wall from one hoof was thinned by 25%; this was ascertained by radiography. The contralateral hooves were used as controls. In a material testing machine, hooves were loaded in a ...
Muñoz A, Castejón-Riber C, Castejón F, Rubio DM, Riber C.Simulated hypoxic normobaric devices have been used in human beings in order to enhance endurance capacity. These devices are sealed chambers where the athletes are supposed to stay for at least 6-8 hr daily. The current research assesses the changes in time-domain, spectral and non-geometrical heart rate variability (HRV) parameters in 6 horses subjected to progressive duration periods inside of a hermetically sealed chamber. It was pursued, firstly to evaluate the intensity of the stress experienced by the animals and secondly to elucidate whether the horses might require an acclimation per...
Plancade S, Clark A, Philippe C, Helbling JC, Moisan MP, Esquerré D, Le Moyec L, Robert C, Barrey E, Mach N.An integrated analysis of gut microbiota, blood biochemical and metabolome in 52 endurance horses was performed. Clustering by gut microbiota revealed the existence of two communities mainly driven by diet as host properties showed little effect. Community 1 presented lower richness and diversity, but higher dominance and rarity of species, including some pathobionts. Moreover, its microbiota composition was tightly linked to host blood metabolites related to lipid metabolism and glycolysis at basal time. Despite the lower fiber intake, community type 1 appeared more specialized to produce ace...
Ohmura H, Hiraga A, Aida H, Kuwahara M, Tsubone H, Jones JH.To determine whether evaluation of heart rate (HR) and HR variability (HRV) during prolonged road transportation in horses provides a sensitive index of autonomic stimulation. Methods: Five 2-year-old Thoroughbreds. Methods: ECGs were recorded as horses were transported for 21 hours in a 9-horse van. Heart rate, high-frequency (HF) power, low-frequency (LF) power, and LF-to-HF ratio from Fourier spectral analyses of ECGs were calculated and compared with values recorded during a 24-hour period of stall rest preceding transportation. Results: HR, HF power, and LF power had diurnal rhythms durin...
Melnick JL, Hampil B.This paper summarizes the results of co-operative studies undertaken by the WHO International Reference Centre for Enteroviruses and a number of WHO Regional Reference Centres for viruses, WHO Virus Collaborating Laboratories, or other laboratories in a comprehensive testing programme of enterovirus equine antisera. The studies were designed to appraise the specificity of immune serum prepared in horses against five representative prototype enteroviruses (poliovirus 1, coxsackieviruses A9 and B3, and echoviruses 4 and 11). Tests for neutralizing antibody were performed not only against the hom...
Ryan T, Smith R.Low level laser therapy (LLLT) is frequently used in the treatment of wounds, soft tissue injury and in pain management. The exact penetration depth of LLLT in human tissue remains unspecified. Similar uncertainty regarding penetration depth arises in treating animals. This study was designed to test the hypothesis that transmission of LLLT in horses is increased by clipping the hair and/or by cleaning the area to be treated with alcohol, but is unaffected by coat colour. A LLLT probe (810 nm, 500 mW) was applied to the medial aspect of the superficial flexor tendon of seventeen equine forelim...
Hackett ES, Lunn DP, Ferris RA, Horohov DW, Lappin MR, McCue PM.Neonatal sepsis is a common problem in foals and is a primary cause of death in the post natal period. Transient bacteraemia and subsequent host responses have not been described in the equine neonate. Objective: The primary objective of this study was to determine if transient bacteraemia occurs in foals within the first 72 h of life. Additional objectives included description of bacterial organisms associated with transient bacteraemia and concurrent cytokine gene expression in healthy foals. Methods: Prospective observational study in healthy foals. Methods: Blood was aseptically collecte...
Bazzano M, McLean A, Tesei B, Gallina E, Laus F.Selenium and vitamin E protect the body against oxidative stress. Clinical manifestations of their deficiency in equids include neurologic and muscular symptoms. Despite the importance of donkeys as working and production animals, there is a dearth of scientific data on selenium and vitamin E normal values. Therefore, the aim of this study was to investigate the plasma concentrations of selenium and vitamin E in healthy donkeys belonging to different ages, sexes, and productive phases. Animals were divided into five groups including foals (group A: n = 7, n = 4 males and n = 3 females), wea...
Arosalo BM, Raekallio M, Rajamäki M, Holopainen E, Kastevaara T, Salonen H, Sankari S.The aim of the study was to investigate urine matrix metalloproteinase (MMP-2 and -9) activity, alkaline phosphatase/creatinine (U-AP/Cr) and gamma-glutamyl-transpeptidase/creatinine (U-GGT/Cr) ratios, glucose concentration, and urine protein/creatinine (U-Prot/Cr) ratio and to compare data with plasma MMP-2 and -9 activity, cystatin-C and creatinine concentrations in colic horses and healthy controls. Horses with surgical colic (n = 5) were compared to healthy stallions (n = 7) that came for castration. Blood and urine samples were collected. MMP gelatinolytic activity was measured by zymogra...
Parlevliet JM, Pearl CA, Hess MF, Famula TR, Roser JF.The presence of steroids and their receptors throughout development, specifically androgen receptor (AR), estrogen receptor alpha (ERalpha) and estrogen receptor beta (ERbeta), in the epididymis of a high estrogen producing species like the stallion has not been determined. Epididymal and testicular samples were collected for analysis of testosterone and estradiol-17beta (E(2)) concentrations and for immunolocalization of AR, ERalpha and ERbeta. The concentration of testosterone in the testis and epididymis were not different among age groups (P>0.05). AR was localized in the principal cell...
Karme A, Rannikko J, Kallonen A, Clauss M, Fortelius M.Different diets wear teeth in different ways and generate distinguishable wear and microwear patterns that have long been the basis of palaeodiet reconstructions. Little experimental research has been performed to study them together. Here, we show that an artificial mechanical masticator, a chewing machine, occluding real horse teeth in continuous simulated chewing (of 100 000 chewing cycles) is capable of replicating microscopic wear features and gross wear on teeth that resemble wear in specimens collected from nature. Simulating pure attrition (chewing without food) and four plant material...
Ortiz-Rodríguez JM, Martín-Cano FE, Gaitskell-Phillips GL, Silva A, Ortega-Ferrusola C, Gil MC, Peña FJ.Energy metabolism in spermatozoa is complex and involves the metabolism of carbohydrate fatty acids and amino acids. The ATP produced in the electron transport chain in the mitochondria appears to be crucial for both sperm motility and maintaining viability, whereas glycolytic enzymes in the flagella may contribute to ATP production to sustain motility and velocity. Stallion spermatozoa seemingly use diverse metabolic strategies, and in this regard, a study of the metabolic proteome showed that Gene Ontology terms and Reactome pathways related to pyruvate metabolism and the Krebs cycle were pr...
Ohmura H, Matsui A, Hada T, Jones JH.Training of young Thoroughbred horses must balance development of cardiopulmonary function and aerobic capacity with loading of the musculoskeletal system that can potentially cause structural damage and/or lameness. High-speed equine treadmills are sometimes used to supplement exercise on a track in the training of young Thoroughbreds because the horse can run at high speeds but without the added weight of a rider. We tested the hypothesis that intermittent high-intensity exercise on a treadmill of young Thoroughbred horses entering training can enhance development of aerobic capacity (VO2max...
Individual animals vary in their behaviour and reactions to novel situations. These differences may extend to differences in cognition among individuals. We tested twenty-six horses for their ability to detour around symmetric and asymmetric obstacles. All of the animals were able to get around the barrier to reach a food target, but varied in their approach. Some horses moved slowly but were more accurate in choosing the shortest way. Other horses acted quickly, consistently detoured in the same direction, and did not reliably choose the shortest way. The remaining horses shifted from a faste...
Bernet A, Bastien A, Soulet D, Jerczynski O, Roy C, Bianchi Rodrigues Alves M, Lecours C, Tremblay MÈ, Bailey JL, Robert C, Belleannée C.Where are primary cilia (PC) organelles located during postnatal epididymal development? Our findings unveil the existence of PC sensory organelles in different epididymal cell types according to postnatal development stage. Primary cilia are sensory organelles that orchestrate major signaling pathways during organ development and homeostasis. Epididymal PC have been detected in the horses, donkey and mules but their cell-lineage specificity has never been investigated in this organ. A longitudinal study was performed by examining tissue from n = 3 to n = 10 transgenic mice at different times ...
Moczygemba C, Guidry J, Wittung-Stafshede P.Native myoglobin (Mb) consists of two populations which differ in the orientation of the heme by 180 degrees rotation (as verified by nuclear magnetic resonance) but have identical absorption spectra and equilibrium-thermodynamic stability. Here, we report that these two fractions of native oxidized Mb (from horse) both unfold and refold (chemical denaturant, pH 7, 20 degrees C) in two parallel kinetic reactions with rate constants differing 10-fold. In accord, the oxidized heme remains coordinated to unfolded horse Mb in up to 4 M guanidine hydrochloride (pH 7, 20 degrees C).
Dane DM, Hsia CC, Wu EY, Hogg RT, Hogg DC, Estrera AS, Johnson RL.The spleen acts as an erythrocyte reservoir in highly aerobic species such as the dog and horse. Sympathetic-mediated splenic contraction during exercise reversibly enhances convective O2 transport by increasing hematocrit, blood volume, and O2-carrying capacity. Based on theoretical interactions between erythrocytes and capillary membrane (Hsia CCW, Johnson RL Jr, and Shah D. J Appl Physiol 86: 1460-1467, 1999) and experimental findings in horses of a postsplenectomy reduction in peripheral O2-diffusing capacity (Wagner PD, Erickson BK, Kubo K, Hiraga A, Kai M, Yamaya Y, Richardson R, and Sea...
Marntell S, Nyman G, Hedenstierna G.To compare pulmonary function and gas exchange in anaesthetized horses during and after breathing either O2-rich gas mixtures or air. Methods: Six healthy standard bred trotters (age range 3-12 years; mass range 423-520 kg), four geldings and two mares. Study design Randomized, cross-over experimental study. Methods: Horses were anaesthetized on two occasions with tiletamine-zolazepam after pre-anaesthetic medication with acepromazine, romifidine and butorphanol. After endotracheal intubation and positioning in left lateral recumbency, animals were allowed to breathe spontaneously. One of two,...
McD￮ LA, Esparza Gonzalez BP, Nino-Fong R, Aburto E.Autologous mesenchymal stem cells (MSCs) have been used as a potential cell-based therapy in various animal and human diseases. Their differentiation capacity makes them useful as a novel strategy in the treatment of tissue injury in which the healing process is compromised or delayed. In horses, bone healing is slow, taking a minimum of 6-12 months. The osteogenic capacity of equine bone marrow and muscle MSCs mixed with fibrin glue or phosphate-buffered saline (PBS) as a scaffold is assessed. Bone production by the following groups was compared: Group 1, bone marrow (BM) MSCs in fibrin glue;...
Hiney KM, Nielsen BD, Rosenstein D.The hypothesis that short-duration exercise may ameliorate the decrease in bone mass observed with confinement was investigated with 18 quarter horses (nine colts and nine fillies) weaned at 4 mo of age and placed into box stalls. After a 5-wk adjustment period, individuals were grouped by age and weight, and then divided randomly into three treatment groups: 1) group housed; 2) confined with no exercise; and 3) confined with exercise. The confined and exercised groups were housed in 3.7 m x 3.7 m box stalls for the 56-d duration of the trial. The exercised group was sprinted 82 m/d, 5 d/wk, i...
Touzot-Jourde G, Stedman NL, Trim CM.To investigate the effect of endotracheal tube cuff inflation pressure on the occurrence of liquid aspiration and tracheal wall damage. Methods: Prospective, randomized experimental study. Methods: Ten healthy horses, weighing 535 +/- 55 kg. Methods: Horses were anesthetized, orotracheally intubated, placed in dorsal recumbency, and maintained on isoflurane in oxygen with controlled ventilation for 175 +/- 15 minutes. The horses were randomly assigned to an endotracheal cuff pressure of 80-100 or 120 cm H2O. The cuff pressure was continuously monitored and maintained at a constant pressure. Me...
Schroeder B, Boyle MD, Sheerin BR, Asbury AC, Lottenberg R.Our laboratory previously demonstrated that group C streptococcal isolates from humans and horses secrete streptokinases that preferentially activate plasminogens reflecting the origin of the isolates. To analyze the significance of these findings, series of streptokinase-producing Streptococcus equisimilis isolates recovered from humans and horses were examined. Southern blot analysis revealed that chromosomal DNA of the streptococcal isolates from humans reacted exclusively with a skc(hu) probe and that chromosomal DNA of streptococcal isolates from horses reacted preferentially with an skc(...
Patterson L, Staiger EA, Brooks SA.The Mangalarga Marchador (MM) is a Brazilian horse breed known for a uniquely smooth gait. A recent publication described a mutation in the DMRT3 gene that the authors claim controls the ability to perform lateral patterned gaits (Andersson et al. 2012). We tested 81 MM samples for the DMRT3 mutation using extracted DNA from hair bulbs using a novel RFLP. Horses were phenotypically categorized by their gait type (batida or picada), as recorded by the Brazilian Mangalarga Marchador Breeders Association (ABCCMM). Statistical analysis using the plink toolset (Purcell, 2007) revealed significant a...
Human movement scienceNovember 28, 2014
Volume 39 121-137 doi: 10.1016/j.humov.2014.06.011
Garner BA, Rigby BR.A prevailing rationale for equine assisted therapies is that the motion of a horse can provide sensory stimulus and movement patterns that mimic those of natural human activities such as walking. The purpose of this study was to quantitatively measure and compare human pelvis motions when walking to those when riding a horse. Six able-bodied children (inexperienced riders, 8-12years old) participated in over-ground trials of self-paced walking and leader-paced riding on four different horses. Five kinematic measures were extracted from three-dimensional pelvis motion data: anteroposterior, sup...
Hobbs SJ, Bertram JE, Clayton HM.Background. Although the trot is described as a diagonal gait, contacts of the diagonal pairs of hooves are not usually perfectly synchronized. Although subtle, the timing dissociation between contacts of each diagonal pair could have consequences on gait dynamics and provide insight into the functional strategies employed. This study explores the mechanical effects of different diagonal dissociation patterns when speed was matched between individuals and how these effects link to moderate, natural changes in trotting speed. We anticipate that hind-first diagonal dissociation at contact increa...
Boisseau M, Dhorne-Pollet S, Bars-Cortina D, Courtot É, Serreau D, Annonay G, Lluch J, Gesbert A, Reigner F, Sallé G, Mach N.The nature and strength of interactions entertained among helminths and their host gut microbiota remain largely unexplored. Using 40 naturally infected Welsh ponies, we tracked the gut microbiota-cyathostomin temporal dynamics and stability before and following anthelmintic treatment and the associated host blood transcriptomic response. High shedders harbored 14 species of cyathostomins, dominated by . They exhibited a highly diverse and temporal dynamic gut microbiota, with butyrate-producing Clostridia likely driving the ecosystem steadiness and host tolerance toward cyathostomins infectio...
Stankov B, Cozzi B, Lucini V, Fumagalli P, Scaglione F, Fraschini F.Melatonin receptors were characterized in the brains of three mammals (rabbit, horse and sheep) by an in vitro binding technique, using 2-[125I]iodomelatonin as labelled ligand. Although binding sites for melatonin have been described recently in several vertebrate species (including the sheep), the rabbit and the horse have not been the subject of investigation so far. Apart from characterization, the present report describes receptor distribution in a number of brain regions, thus allowing for direct interspecies comparison under the same methodological conditions. 2-[125I]iodomelatonin labe...
Evenberg A, Meyer H, Gaastra W, Verheij HM, De Haas GH.The complete amino acid sequence of phosphlipase A2 (EC 3.1.1.4) from horse pancreas was determined. The protein controls of a single polypeptide chain of 125 amino acids and has a molecular weight of 13,927. The chain is crosslinked by seven disulfide bridges. The sequence was determined by automated Edman degradation of the intact protein and several of the large peptide fragments. Smaller peptides were analyzed by manual Edman degradation. Fragmentation of the peptide chain was accomplished by enzymatic digestion with trypsin, chymotrypsin, and thermolysin. The final overlap was found by di...
Virén T, Huang YP, Saarakkala S, Pulkkinen H, Tiitu V, Linjama A, Kiviranta I, Lammi MJ, Brünott A, Brommer H, Van Weeren R, Brama PA, Zheng YP....The aim of this study was to compare sensitivity of ultrasound and optical coherence tomography (OCT) techniques for the evaluation of the integrity of spontaneously repaired horse cartilage. Articular surfaces of horse intercarpal joints, featuring both intact tissue and spontaneously healed chondral or osteochondral defects, were imaged ex vivo with arthroscopic ultrasound and laboratory OCT devices. Quantitative ultrasound (integrated reflection coefficient (IRC), apparent integrated backscattering coefficient (AIB) and ultrasound roughness index (URI)) and optical parameters (optical refle...
Popescu S, Diugan EA.The aim of this observational study was to investigate if a relationship exists between the calculated overall individual welfare score (as an indicator of the welfare quality) and the neutrophil:lymphocyte (N:L) ratio (as a stress indicator) in working (draught) and reproduction horses (breeding stallions and broodmares), in two different seasons. The welfare of the horses was assessed by a protocol which included health and behavioural parameters. An individual welfare score was computed, the total and differential WBC count was established and the N:L ratio was calculated for each of the 14...
Crevier-Denoix N, Ruel Y, Dardillat C, Jerbi H, Sanaa M, Collobert-Laugier C, Ribot X, Denoix JM, Pourcelot P.The objective of this study was to test the hypothesis that tendon echogenicity is associated with the material properties of the corresponding tendon site, especially in case of lesions, due to local changes in tendon matrix composition. Four normal and nine spontaneously injured equine superficial digital flexor tendons (SDFT) were isolated then ultrasonographically examined under tension, in a special device placed in a water bath. Ultrasonographic transversal images (7.5MHz linear transducer) of five segments along each tendon were digitized, and analyzed in order to measure the mean cross...
Soma LR, Uboh CE, Liu Y, Li X, Robinson MA, Boston RC, Colahan PT.This study investigated and compared the pharmacokinetics of intra-articular (IA) administration of dexamethasone sodium phosphate (DSP) into three equine joints, femoropatellar (IAS), radiocarpal (IAC), and metacarpophalangeal (IAF), and the intramuscular (IM), oral (PO) and intravenous (IV) administrations. No significant differences in the pharmacokinetic estimates between the three joints were observed with the exception of maximum concentration (Cmax ) and time to maximum concentration (Tmax ). Median (range) Cmax for the IAC, IAF, and IAS were 16.9 (14.6-35.4), 23.4 (13.5-73.0), and 46.9...
Nouri-Sorkhabi MH, Agar NS, Sullivan DR, Gallagher C, Kuchel PW.The phospholipid classes of erythrocyte membranes and plasma from several domestic animals and marsupials were quantified by 31P NMR using detergents. Washed erythrocyte samples were thoroughly haemolysed by tip-sonication and dissolved in sodium cholate; plasma samples were dissolved in Triton X-100. The species studied were: common wombat (Vombatus ursinus), black-striped wallaby (Macropus dorsalis), bandicoot (Isoodon macrocarpus), Eastern grey kangaroo (Macropus giganteus), Tammar wallaby (Macropus eugenii), sheep (Ovis aries), goat (Capra hircus), cattle (Bos taurus), horse (Equus caballu...
