The study of blood in horses encompasses the examination of its components, functions, and its role in equine health and disease. Blood consists of various elements, including red blood cells, white blood cells, platelets, and plasma, each serving specific functions such as oxygen transport, immune response, clotting, and nutrient distribution. Analyzing blood parameters can provide insights into the physiological and pathological states of horses. Common blood tests in equine medicine assess parameters like hematocrit, hemoglobin concentration, and white cell counts to monitor health status, diagnose conditions, and guide treatment decisions. This page compiles peer-reviewed research studies and scholarly articles that explore the composition, function, and clinical applications of blood analysis in horses.
HORI J, AOKI K.Electrophoretic studies were made of normal horse and human serum albumins over the pH range 3.6–6.8 and at 25 °. The ionic strength of acetate or phosphate buffer used was 0.1, and the concentration of protein was 0.5% (g./100 ml.). Patterns were usually enantiographic and there were two (N and F1) or three (N, F1, and F2) boundaries in the pH range 3.6–5.2. The areas of the N and F1 boundaries changed continuously with pH, and the area of F2 was almost constant. The results were interpreted, in the same way as was previously done in the case of bovine serum albumin, by the isomerization...
SHORT RV.Progesterone levels have been measured in the peripheral blood of pregnant and non-pregnant
mares, and in umbilical cord blood collected during foaling. It was found that progesterone was
readily detectable in the blood of pregnant and non-pregnant animals provided that there was a
fully developed corpus luteum present in the ovaries. During the second half of gestation, when
the ovaries have become fibrotic, progesterone was no longer detectable in the peripheral blood,
even though it was present in high concentrations in umbilical cord blood.
The reasons for this apparent disappearance...
Poochipakorn C, Wonghanchao T, Huangsaksri O, Sanigavatee K, Joongpan W, Tongsangiam P, Charoenchanikran P, Chanda M.During an African horse sickness (AHS) outbreak, horses were able to exercise daily in a net-covered arena, yet the physiological responses to exercise in a netted arena was unknown. In a cross-over study design, eight horses performed a 39-minute aerobic exercise in conventional (CA) and vector-protected arenas (VPA). Horses were slower in some gaits and covered less distance in the VPA arena (P < .01). Cortisol release, hematology, and heart rate variability (HRV) were also examined. An interaction between the riding arena and time was observed in hematocrit (P = .0013), hemoglobin (P = ...
de Laat MA, Sillence MN.Blood glucose concentration is often measured during an oral glucose test (OGT), but is not thought to aid in diagnosing insulin dysregulation (ID) or pituitary pars intermedia dysfunction (PPID). The aim of this retrospective study was to investigate whether the change in blood glucose concentration during an OGT aligned with indicators of equine metabolic syndrome or PPID, including serum insulin and plasma ACTH concentrations, clinical observations, age, sex, breed type and the test dose. The cohort included 149 horses, miniature horses, and ponies that had undergone an in-feed OGT and clin...
Aida H, Foreman JH, Ochi A, Takizawa Y, Yamanaka T.Equine piroplasmosis is an infectious disease caused by Babesia caballi and Theileria equi. A competition horse that had been imported to the Equestrian Park for the Tokyo 2020 Olympic Games and had a fever over 40°C and severe anemia was diagnosed with equine piroplasmosis by blood smear and direct polymerase chain reaction (PCR) tests for Theileria equi. Treatment with protozoan anthelmintics and whole blood transfusion diminished the fever, improved the anemia, and allowed the horse to return home safely. Preparation for routine cases of this infection should include the development of a s...
Barnabé MA, Elliott J, Harris PA, Menzies-Gow NJ.Hypoadiponectinaemia is a risk factor for endocrinopathic laminitis, but the directionality and nature of its association with insulin dysregulation is unclear. Objective: To investigate the effects of short-term induced hyperinsulinaemia and dexamethasone challenge on circulating [total adiponectin] and whole blood expression of adiponectin (AdipoR1 and AdipoR2), insulin, and insulin-like growth factor 1 (IGF-1) receptors in insulin-sensitive ponies. Methods: In vivo experiment. Methods: Six never-laminitic, insulin-sensitive, native-breed UK ponies first underwent a dexamethasone challenge (...
Li S, Guo K, Wang X, Lin Y, Wang J, Wang Y, Du C, Hu Z, Wang X.Equine infectious anemia (EIA) has a worldwide distribution and causes severe economic losses to the equine industry. The EIA virus (EIAV) genome sequences from different countries are highly diverse, which poses a great challenge for pathogen identification with PCR. Phylogenetic analysis showed that although gag is the most conserved structural gene, it still has great genome variability. Currently, most existing PCR methods are designed based on the gag gene sequence and therefore do not cover all the viral strains, especially Asian EIAV strains. In this study, we developed a tat-gag-based ...
Carvalho Seabra J, Martinez do Vale M, Spercoski KM, Hess T, Patricio Viviani de Moura P, Dittrich JR.Keeping horses in single stalls can lead to the development of abnormal and stereotypic behaviors (ASB). Opportunities for social interactions and stall architecture can influence behavior. The current study aimed to identify how three different stall architectures influenced time-budget and physiological parameters in horses. Stall types included: (1) 3.2 × 3.7 m with tactile contact between horses (B1); (2) 2.6 × 3.5 m with visual contact between horses and outside view (B2); (3) 2.3 × 3.4 m with visual contact and outside view (B3). Ten horses from B1 and B3, and nine from B2 were ...
Nava V, Licata P, Biondi V, Catone G, Gugliandolo E, Pugliese M, Passantino A, Crupi R, Aragona F.Horses are excellent bioindicators for the assessment of environmental pollution. The aim of this study was to evaluate the levels and potential bioaccumulation of 28 mineral elements in 75 horse whole blood samples collected from five pollution-prone areas of Sicily, Italy. A direct mercury analyzer (DMA-80) was used for Hg determination, and an inductively coupled plasma mass spectrometer (ICP-MS) for all other elements. A one-way ANOVA test, followed by Bonferroni's multiple comparison for post hoc comparison, was applied to assess statistically significant differences between mineral eleme...
Dorrego A, Camino E, Gago P, Buendia-Andres A, Acurio K, Gonzalez S, de Juan L, Cruz-Lopez F.Equine piroplasmosis (EP) is caused by Theileria equi and Babesia caballi, transmitted by tick vectors. Horses can suffer an acute, subacute, and chronic forms of the disease, with clinical signs such as poor performance, fever, pale mucosal membranes, and jaundice. The diagnosis of EP subclinical cases is complex due to the sensitivity of real-time PCR and the limited parasite load in some carriers, making it challenging to differentiate them from seropositive, PCR negative (S+PCR-) individuals. This study aimed to describe haematological and biochemical changes in asymptomatic EP carriers, E...
Hedia M, Angel-Velez D, Papas M, Peere S, Gerits I, De Coster T, Van den Branden E, Govaere J, Van Soom A, Leroy JLMR, Smits K.The in vitro production of equine embryos via ovum pick-up (OPU) and intracytoplasmic sperm injection (ICSI) has increased rapidly. There is a marked effect of the individual mare on the outcome of OPU-ICSI, but little is known about the influence of the mare's health condition. This study aimed to investigate the potential associations between the concentrations of interleukin-6 (IL-6), reactive oxygen metabolites (d-ROMs), and biological antioxidant potential (BAP) in serum of oocytes' donor mares and the subsequent embryonic development. Just before OPU, a blood sample was collected from 28...
Giers J, Bartel A, Kirsch K, Müller SF, Horstmann S, Gehlen H.Horses competing in cross-country tests are subjected to high physical demands. Within the scope of this prospective longitudinal study, blood values of 20 elite eventing horses were examined before and after two- to four-star cross-country rides. The aim was to find out whether blood-based markers for skeletal muscle and cardiac muscle function change after cross-country exercise. Parameters that provide information about fluid balance, muscle enzymes, metabolites and cardiac muscle-specific markers were investigated. We developed an approach to eliminate the concentration changes caused by r...
Quattrini C, Bozorgmanesh R, Egli P, Magdesian KG.Fecal microbiota transplant (FMT) is increasingly administered as part of the treatment of colitis in horses, yet there is little data as to its effectiveness. Retrospective evaluation of the effects of FMT on discharge status, fecal consistency, length of hospitalization, and improvement in clinical signs in horses hospitalized for diarrhea. Retrospective case-control study. Medical records of adult horses (>1 year old) that received at least one transfaunation treatment (2013-2018) in two referral hospitals were identified through a medical records database search. Medical records of contemp...
Carlier S, Depuydt E, Suls M, Bocqué C, Thys J, Vandenberghe A, Martens A, Saunders J, Hellmann K, Braun G, Beerts C, Spaas JH.Mesenchymal stem cells are an innovative therapeutic for various equine orthopaedic diseases, including soft tissue injuries. Objective: To evaluate the safety and efficacy of tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells (tpMSCs) in horses with naturally occurring superficial digital flexor tendon (SDFT) and suspensory ligament (SL) injuries. Methods: Multicentre, blinded, randomised, placebo-controlled clinical trial. Methods: One hundred client-owned horses with SDFT and SL injuries were randomised to receive an intralesional tpMSC (66) or saline (34) in...
Parra Martínez C, Rico Pérez B, Kaartinen J.To evaluate the agreement between noninvasive arterial blood pressure (NIBP) measured from the tongue and thoracic limb with invasive blood pressure (IBP), and to compare NIBP measured from the tongue and thoracic limb in anaesthetized horses. Methods: Prospective clinical study. Methods: A group of eight client-owned healthy horses anaesthetized for scheduled procedures, American Society of Anesthesiologists classification I-II, weighing (mean ± standard deviation) 498 ± 91 kg and aged 7.8 ± 6.75 years. Methods: Animals were premedicated with intravenous (IV) romifidine (0.04-0.08 mg kg-1)...
Lo Feudo CM, Stucchi L, Stancari G, Conturba B, Bozzola C, Zucca E, Ferrucci F.In racehorses, the associations between physiological parameters obtained by exercise testing and racing results have been questioned. We hypothesized that fitness variables measured during a treadmill incremental test may be related with racing outcomes and lifetime career. Our study aimed to investigate the role of fitness parameters obtained during a treadmill test in performance evaluation and career prediction in poorly performing Standardbreds, through a retrospective review of the clinical records of 245 trotters that underwent an incremental treadmill test. Several fitness parameters w...
Frampton A, Floriano D, Simpson K, Hopster K.To evaluate the agreement between the Tafonius large animal ventilator-integrated volumetric capnography (vCap) software and the Respironics NICO noninvasive cardiac output monitor reference system. Methods: Data were collected from 56 healthy adult horses undergoing general anesthesia. Methods: Animals were placed under general anesthesia and connected to the Tafonius large animal ventilator circle system. A flow partitioning device with CO2 and flow sensors was utilized to couple the endotracheal tube to the NICO monitor. Tafonius CO2 and flow sensors are incorporated into the Y-piece of the...
Barnabé MA, Elliott J, Harris PA, Menzies-Gow NJ.The hormones insulin and adiponectin are commonly measured in equids because of their involvement in endocrinopathic laminitis. These are currently measured in serum/plasma, although jugular venipuncture can cause stress in some animals and may be impossible in needle-shy individuals. However, both hormones can be measured in saliva in other species. Objective: To determine whether [insulin] and [total adiponectin] are detectable in equine saliva using automated assays and whether saliva collection is associated with changes in stress indicators. Additionally, the correlation between serum and...
White JM, Colbath AC, Schott HC.Treatment with phenylbutazone (nonselective COX inhibitor) decreases the diuretic and natriuretic effects of furosemide by nearly 30% but the effects of COX-2 specific inhibitors (firocoxib) and atypical NSAIDs (dipyrone) are unknown. Objective: Furosemide-induced diuresis after pretreatment with firocoxib or dipyrone is diminished to a lesser extent than after pretreatment with phenylbutazone. Methods: Eight healthy mares. Methods: Each mare received 4 treatments in a prospective experimental crossover study using a replicated 4 × 4 Latin Square design: furosemide alone (FU), furosemide an...
Chien RC, Mingqun L, Yan Q, Randolph N, Huang W, Wellman M, Toribio R, Rikihisa Y.The tick-borne obligatory intracellular bacterium Anaplasma phagocytophilum infects humans as well as domesticated and wild animals, causing a febrile disease collectively called granulocytic anaplasmosis. The epidemiology and the host species specificity and zoonotic potential of A. phagocytophilum strains remain unclear. In this study, ankA (encoding ankyrin A) and p44 gene sequences of A. phagocytophilum were determined in clinical specimens from horses in Ohio and compared with those found in A. phagocytophilum strains from various hosts and geographic regions. With increasing numbers of s...
Cecchini Gualandi S, Di Palma T, Boni R.Ceruloplasmin (Cp) assessment in biological samples exploits the oxidase activity of this enzyme against several substrates, such as -phenylenediamine (-P), -dianisidine (-D) and, most recently, ammonium iron(II) sulfate (AIS). Once developed in humans, these assays are often used in veterinary medicine without appropriately optimizing in the animal species of interest. In this study, two assays using AIS and -D as substrates have been compared and validated for Cp oxidase activity assessment in horse's plasma. The optimization of the assays was performed mainly by varying the buffer pH as wel...
Miranda ALS, Antunes BC, Minozzo JC, Lima SA, Botelho AFM, Campos MTG, Chávez-Olórtegui C, Soto-Blanco B.Antivenom production against venom relies on horses being immunized and bled for plasma harvest. One horse can partake in several cycles of antivenom production, which will require years of constant venom and adjuvant inoculation and bleeding. The actual impact on the health of horses that participate in several antivenom-producing cycles is unknown. Therefore, this study aimed to evaluate the general health status of horses that underwent at least six cycles of loxoscelic antivenom production. Seven crossbred horses that had partaken in six to eight complete antivenom-producing cycles were u...
The aim of our study was to analyze circadian rhythm of the hematological profile of horses housed in a loose box and paddock during the different seasons (spring, summer, autumn, and winter). Blood samples were performed every 4 h for 48 consecutive hours. Red blood cells (RBCs), hemoglobin (HGB), hematocrit (HCT), white blood cells (WBCs), platelets (PLTs), and leukocyte subpopulations (neutrophils, basophils, eosinophils, lymphocytes, and monocytes) were analyzed, and, at the same time, environmental conditions were recorded. A statistically significant effect of housing conditions ( < 0...
Viterbo L, Hughes J, Milner PI, Bardell D.The study aimed to investigate if arterial blood analysis in conscious horses presenting with signs of colic and breathing ambient air had diagnostic or prognostic value. Arterial blood samples from 352 horses presenting with colic at a university equine referral hospital were analysed for pH, partial pressure of carbon dioxide (PaCO2), partial pressure of oxygen (PaO2), concentrations of sodium (Na+), potassium (K+), ionised calcium (Ca2+) and chloride (Cl-), actual and standardised plasma bicarbonate concentration (HCO3- (P) and HCO3- (P, st)), blood and extracellular fluid base excess (Base...
Titotto AC, Santos MM, Ramos GV, Adão MDS, Benvenuto GV, De Lacerda LCC, Lisbôa JAN, Lacerda-Neto JC.The effect of lactate minimum speed (LMS)-guided training on horses' homeostasis is still unknown. Thus, this study aimed to evaluate the effect of an LMS-guided training program on the fluid, electrolyte and acid-base status of horses. Ten untrained Arabian horses were submitted to an LMS test on a treadmill before and after six weeks of training. The training intensity was 80% of the LMS in the first three sessions and 100% of the LMS in the other sessions. The venous blood was collected before (T-1) and after (T-2) training at rest, during and after the LMS test for lactate, pH, pCO, HCO, a...
Massie SL, Bezugley RJ, McDonald KJ, Léguillette R.Arrhythmias are commonly reported in exercising horses, however due to regulatory constraints electrocardiograms (ECGs) are acquired during training but not competition, raising questions about the repeatability of findings. The aims were (1) compare training and competition arrhythmias and (2) describe the repeatability of arrhythmias during maximal-intensity exercise. A convenience sample of 52 healthy Thoroughbreds (aged 8.7 ± 2.5 years) competing in the World Professional Chuckwagon Association were obtained, totaling 152 training or competition ECGs (2-7 ECGs/horse). Speed, heart rate ...
Ugulu I, Khan ZI, Ahmad K, Bashir H, Mehmood N, Zafar A.The present study aimed to determine the accumulation levels of arsenic in pasture soil, forage and animals. An atomic absorption spectrophotometer was used to determine the concentration of metals in the samples of soil, forage and blood plasma of horses. The level of arsenic ranged between 4.26 mg/kg (summer) and 4.66 mg/kg (winter) in soil samples and 2.67 mg/kg (summer) and 2.94 mg/kg (winter) in forage samples. In blood plasma samples, the mean arsenic (As) values varied between 1.38 and 1.52 mg/L. In the blood plasma samples, the mean As values varied between 1.38 and 1.52 mg/L. No...
Knych HK, Katzman S, McKemie DS, Arthur RM, Blea J.Lidocaine is a local anesthetic that is sometimes administered in combination with epinephrine. The addition of epinephrine increases the time lidocaine remains at the site of administration, thus prolonging the duration of effect. Due to their potential to prevent the visual detection of lameness, the administration of local anesthetics is strictly regulated in performance and racehorses. Recent reports of positive regulatory findings for lidocaine in racehorses suggests a better understanding of the behavior of this drug is warranted. The objective of the current study was to describe serum ...
Cappelli K, Mecocci S, Porceddu A, Albertini E, Giontella A, Miglio A, Silvestrelli M, Verini Supplizi A, Marconi G, Capomaccio S.With his bicentennial breeding history based on athletic performance, the Thoroughbred horse can be considered the equine sport breed. Although genomic and transcriptomic tools and knowledge are at the state of the art in equine species, the epigenome and its modifications in response to environmental stimuli, such as training, are less studied. One of the major epigenetic modifications is cytosine methylation at 5' of DNA molecules. This crucial biochemical modification directly mediates biological processes and, to some extent, determines the organisms' phenotypic plasticity. Exercise indeed...
Scantamburlo G, Nofziger C, Paulmichl M, Vanoni S.Because of their importance as companion animals or as racehorses, horses can be treated with various drugs. Although it is known that drug withdrawal times can vary for each horse, pharmacogenetics for these animals has not been adequately studied and requires further development. Since is responsible for the metabolism of 25-30% of drugs in humans, including some used to treat horses, a study of the family in horses was conducted to define its genetic structure as well as its expression pattern in the liver. Unassigned: Genomic DNA extracted from venous blood and mRNA from fresh liver tiss...
Richards T, Burron S, McCorkell TC, Trevizan L, Patterson K, Minikhiem D, Ma DWL, Pearson W, Shoveller AK.Camelina oil is derived from a low-input, high-yield crop and, in comparison to many other dietary fat sources currently used in equine diets, provides a greater amount of α-linolenic acid [ALA; (n-3)], than linoleic acid [LA; (n-6)]. However, no research exists assessing the effects of feeding camelina oil to horses in contrast to other commonly used oils. The objective of this study was to compare the effect of supplementing camelina oil to that of flaxseed and canola oil supplementation, on outcomes related to skin and coat health in horses. Thirty adult horses [23 mares, 7 geldings; 14.9 ...
Taylor SD, Hart KA, Vaughn S, Giancola SC, Serpa PBS, Santos AP.Ascorbic acid (AA) is an antioxidant that might be beneficial for adjunctive treatment of sepsis in horses. The optimal dose and effects on oxidative status are unknown. Objective: Ascorbic acid administration will increase plasma AA concentrations and decrease determinants of reactive oxygen metabolites (dROM), basal and stimulant-induced intraerythrocytic reactive oxygen species (ROS) concentrations, and stimulant-induced neutrophil ROS production, and increase plasma antioxidant capacity (PAC) in a dose-dependent manner. Methods: Eight healthy horses. Methods: Randomized placebo-controlled ...
