Serum in horses refers to the component of blood that remains after the removal of cells and clotting factors. It contains a variety of proteins, electrolytes, hormones, and metabolic waste products. Serum analysis is a valuable tool in veterinary medicine for assessing the health status of horses. It provides insights into organ function, nutritional status, and the presence of disease. Common parameters measured in equine serum include enzymes, such as aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT), as well as electrolytes like sodium and potassium. This page assembles peer-reviewed research studies and scholarly articles that explore the composition, diagnostic applications, and implications of serum analysis in equine veterinary practice.
Rouse BT, Ditchfield WJ.The antibody response in serum and nasal secretions of groups of ponies vaccinated or infected with Myxovirus influenzae A-equi 2 was examined. Following infection by aerosol with live virus, a weak antibody response was recorded in both serum and secretions. Antibody levels were undetectable in secretions at 31 days after infection. After primary intramuscular vaccination with killed virus, using sodium alginate as an adjuvant, antibody was detected only in the serum. However, following revaccination, a pronounced antibody response was demonstrated in both serum and secretions. Antibody was s...
Rouse BT, Ditchfield WJ.Nasal secretions and serum were collected from ponies in order to determine the types of immunoglobulins responsible for antibody activity against Myxovirus influenzae A-equi 2. Using specific antisera to remove each immunoglobulin, the antiviral activity of serum was shown to be a property of IgG globulin, whereas in nasal secretions activity was found in both IgG and IgG(T) globulins. However in secretions the predominant activity was attributed to IgG(T) globulin. Because of its sensitivity to 2 mercaptoethanol, early serum antibody was assumed to belong to the IgM class of immunoglobulins....
Ek N.A method for the rapid electrophoresis on a cellulose acetate membrane of serum proteins from horses, sheep and pigs is discussed. The various main globulin fractions in the serum of these animals were experimentally identified. Normal values for the percentage composition of serum from normal horses, sheep and pigs were calculated. In the horse there was great individual variation in the shape of the β-fraction, assumed to be due to different transferrin types. The mean value for β-globulin of 19.5 % in the horse was higher than for the other two species. The albumin percentage was highest ...
Kemeny L, Pearson JE.An agent which possessed the properties of herpesviruses was isolated from the leukocytes of 71 out of 80 (88.7%) apparently normal Iowa horses. It was ether- and heat-sensitive, DNA type, and produced type-A intranuclear inclusion bodies in cell cultures. Electron micrographs revealed a virion of typical herpesvirus structure. Leukocyte isolate virus could be differentiated from equine rhinopneumonitis virus (ERV) by serum neutralization, by growth differences in rabbit kidney cells, and by fluorescent antibody staining. Specific neutralizing antibody against this agent was found in a pooled ...
Müller F, Segerling M.Complement activity in the serum of eight species has been studied in two ways: by immobilization of sensitized with human or rabbit antibody and by haemolysis of sheep red cells sensitized with rabbit antibody. Serum of the pig, monkey and man was actively haemolytic but contained a heatlabile factor that immobilized unsensitized in the presence of guinea-pig complement and precluded the detection of immune immobilizing activity. Sera of other species, although without action on unsensitized treponemes, even with added guinea-pig complement, differed in their relative haemolytic and immobil...
Boulanger P, Bannister GL, Ruckerbauer GM, Corner AH.Clinical field cases of equine infectious anemia were studied and the disease was reproduced experimentally in horses. Attempts were made to adapt the complement-fixation test to the detection of antibodies in the serum of infected animals and to the demonstration of antigens in tissue extracts.A moderate complement-fixing antibody response was demonstrated in the serum of horses shortly after primary exposure to the infectious agent. However, this reactivity was of short duration and occurred with normal as well as with infected saline tissue extracts. It was therefore concluded that this rea...
Turner GA, Taylor DM.The interactions between tetravalent plutonium and horse serum proteins were studied in vitro by electrophoresis on cellulose acetate and by gel filtration. The results show that in horse serum, as in other mammalian sera, the plutonium is associated principally with the transferrin component of the beta1-globulins. The formation of the plutonium-transferrin complex requires the presence of HCO3-, and plutonium is displaced from the complex by excess iron, thus indicating that similar binding sites may be involved in the complexing of iron and plutonium. The plutonium complex is considered to ...
Denny JE.Horses receiving a pelleted or cubed dietary supplementation with roughage, have serum inorganic phosphate (SIP) concentrations consistently below an accepted mean of 1,032 mmol l-1 or 3, 1 mg dl-1. Further, it has been reported that the best eight, two-year-old Irish Thoroughbred track performers of 51 horses tested over a 10 month period, had significantly lower SIP concentrations than the worst eight track performers. In an endeavour to assess any nutritive effect on SIP concentrations and also to assess any effect of SIP concentrations on track performance, metabolic blood profiles from 30...
Mora-Pereira M, Boone L, Naskou M, Wooldridge A.To evaluate ex vivo angiogenesis of equine arterial rings in response to various growth media. Methods: Facial arteries were dissected from 11 horses post-euthanasia. Equine platelet lysate (ePL) was harvested from 6 horses. Methods: Arteries were exposed to endothelial growth media (EGM) + horse serum (HS) for first sprout (FS), vascular regression (VR), and (basement membrane matrix [Matrigel]) lysis (ML) evaluation. Additional rings supplemented with (1) EGM, (2) EGM + EDTA, (3) endothelial basal media (EBM), (4) EBM + HS, or (5) EBM + human VEGF were compared for vascular network area (VNA...
Yamamoto M, Yamamoto I, Tanaka Y, Sugano M.1. A method for the purification of horse serum lecithin:cholesterol acyltransferase has been established. 2. The method involves the adsorption of the enzyme from diluted horse serum on DEAE-Sephadex A-50, (NH4)2SO4 fractionation, 1-butanol treatment, and chromatographic techniques of DEAE-Sepharose CL-6B, DEAE-Sephadex A-50, Affi-Gel blue and hydroxylapatite. 3. The resultant enzyme preparation essentially formed a single main band when subjected to polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. 4. The final purification of the enzyme was 20,000-fold with 7% yi...
Jones S, Blackmore DJ.The distribution of the isoenzymes of aspartate aminotransferase (AST, E.C. 2.6.1.1.) in equine tissues has been studied to ascertain whether the organ of origin may be identified when the total AST activity of serum is raised. Most tissues contain 3 isoenzymes of cytoplasmic origin (cAST) with isoelectric points of 5.6, 5.7 and 5.9, and one isoenzyme of mitochondrial (mAST) origin with an isoelectric point of 9. Serum from horses with azoturia contained an additional cytoplasmic subform with an isoelectric point of 5.8. This form could not be generated by ageing, freezing and thawing or bindi...
Daly AE, Deible CG, Lamb CE, Santacaterina SM, Marzolf NL, Page AE, Horohov DW, Wood PL, Werre SR, Chapman SE, Christmann U.To evaluate surfactant protein D (SP-D) concentrations in serum and bronchoalveolar lavage fluid (BALF) from young healthy horses on pasture or housed in a typical barn. Methods: 20 young healthy horses. Methods: Horses were randomly assigned to 1 of 2 groups (pasture, n = 10; barn, 10), and serum and BALF samples were collected for SP-D determination at baseline (all horses on pasture) and 2 weeks and 4 weeks after the barn group of horses was relocated from the pasture to the barn. Other evaluations included physical and tracheoscopic examinations. Findings were compared within and between g...
BonenClark GD, MacKay RJ, Ward RE, Sheerin B.To evaluate the humoral response of horses to vaccination, using a murine monoclonal anti-idiotypic antibody (A4) that shares an epitope with lipid A. Methods: Serum concentrations of antilipid A antibody and 1C9 (epitope on murine monoclonal antilipid A antibody) were measured serially during the period of vaccination with A4. Methods: 6 clinically normal adult ponies. Methods: Ponies were inoculated IM 3 times at monthly intervals with A4. Two weeks after each inoculation, serum was obtained and was assayed by ELISA for antilipid A and 1C9 concentrations. Additional vaccinations were given t...
Ansar Ahmed S, Furr M, Chickering WR, Sriranganathan N, Sponenberg DP.Immunological, clinical, and pathological investigations were conducted on a horse with lymphosarcoma. The immunological status was investigated by measuring the level of antibodies by single radial immunodiffusion test and the ability of lymphocytes to proliferate in response to mitogens. Multiple immunological abnormalities were noted in this horse. They were; (1) decreased IgM, IgG, and IgA levels in the serum despite hyperproteinemia; (2) increased in-vitro spontaneous lymphoproliferation which reflects augmented mitosis; (3) decreased lymphoproliferative response to T cell stimulants (e.g...
Knych HK, Stanley SD, Arthur RM, McKemie DS.Cetirizine is an antihistamine used in performance horses for the treatment of hypersensitivity reactions and as such a withdrawal time is necessary prior to competition. The objective of the current study was to describe the disposition and elimination of cetirizine following oral administration in order to provide additional serum concentration data upon which appropriate regulatory recommendations can be established. Nine exercised thoroughbred horses were administered 0.4 mg/kg of cetirizine orally BID for a total of five doses. Blood samples were collected immediately prior to drug admin...
Targowski SP.All chronically diarrheal horses given (orally) 2 series of treatments with normal horse serum recovered in 2 to 4 weeks. However, mild diarrhea sometimes persisted several months in the group of horses with severe diarrhea. Weight gains were approximately 35% in horses with severe diarrhea and approximately 10% in horses with mild diarrhea. Serum specimens from 12 diarrheal and 20 normal horses were examined for immunoglobulins by single radial immunodiffusion technique. Concentration of immunoglobulin A in serum of diarrheal horses was approximately 50% lower than that in serum of normal hor...
Didkowski S, Kaminski M, Kerjan P, Tomaszewska-Guszkiewicz K, Zurkowski M.By the method of precipitation with Rivanol (2-ethoxy-6,9-diaminoacridine lactate) and ammonium sulphate followed by chromatography on DEAE cellulose three genetic variants of transferrin were purified from equine serum: D, M and R. Their molecular mass determined in this study was 80 000, and it was identical for all three variants, which differed slightly in their amino acid composition. The protein level was determined in the serum of 535 two-year-old thoroughbred English horses by the method of rocket immunoelectrophoresis using antibodies obtained against three transferrins. The individua...
Wallace GE, McKaba VF, Reinhart JM, Li Z, Austin S, Fries RC.Large vessel and microvascular thrombi are common complications in systemically ill horses contributing to patient morbidity and mortality. Apixaban, an oral factor Xa inhibitor, shows excellent efficacy against stroke and deep vein thrombosis in humans. The purpose of this study was to determine serum apixaban concentrations and anti-factor Xa activity in horses after orally administered apixaban. Five horses received a single dose of intravenous (0.09 mg/kg) and oral (1 mg/kg) apixaban in a cross-over design. Serum apixaban concentrations and anti-Xa activity were measured serially via liq...
Snyder JR, Pascoe JR, Hietala SK, Holland M, Baggot DJ.Gentamicin sulfate (2.2 mg/kg of body weight, IV) was given to anesthetized horses. Jejunal and large colon tissue samples (1 g), serum, and urine were collected over a 4-hour period. Maximum gentamicin concentrations in serum (10.06 +/- 2.85 micrograms/ml) occurred at 0.25 hours after injection. Maximum gentamicin concentrations in the large colon (4.13 +/- 1.80 micrograms/ml) and jejunum (2.26 +/- 1.35 micrograms/ml) occurred in horses at 0.5 and 0.33 hours, respectively. Tissue concentrations decreased in parallel with serum concentrations and were still detectable at the end of the 4-hour ...
Kent MG, Schneller HE, Hegsted RL, Johnston SD, Wachtel SS.The XY Sex Reversal Syndrome of the horse is a condition associated with female or intersexual development in genetic males. In our previous study, 38 sex reversed XY mares were classified according to behavior, gross clinical phenotype, gonadal status, and H-Y phenotype. Four classes were described, ranging from potentially fertile female (Class I) to virilized intersex (Class IV). In the present study, serum testosterone concentrations were measured in 29 sex-reversed XY mares, 3 normal mares and 3 normal stallions. Serums were obtained during the breeding season (March-August), and were sto...
Booth LC, Oxender WD, Douglas RH, Woodley SL.A gonadotropin-releasing hormone (GnRH) was injected in mares given prostaglandin F2 alpha (PGF2 alpha) to induce luteolysis in an attempt to sunchronize ovulation. Pretreatment with estradiol-17 beta (E2-17 beta) was used to determine whether or not estradiol would enhance the release of luteinizing hormone (LH) after treatment with GnRH. Twelve mares were used in a balanced Latin square crossover design. Mares were injected with PGF2 alpha, treatment A; PGF2 alpha mgnRH, treatment B; or PGF2 alpha me2-17 beta mgnRH, treatment C. The interval +/- SEM from PGF2 alpha injection to estrus was 3....
Raisis AL, Hodgson JL, Hodgson DR.Twenty-one compromised neonatal foals hospitalised at the Rural Veterinary Centre (RVC) during 1993 were studied to determine i) serum gentamicin concentrations obtained when gentamicin was administered at 3.3 mg/kg bwt twice daily i.m.; ii) factors which contributed to inter-foal variation in serum gentamicin concentrations achieved and iii) clinical efficacy of gentamicin therapy in foals with confirmed septicaemia. Septicaemia was confirmed in 7 foals with positive blood cultures and suspected in 8 foals with a sepsis score > 11. Peak serum concentrations (Ps) were > 6 microg/ml in al...
Hope E, Johnston SD, Hegstad RL, Geor RJ, Murphy MJ.A commercially available radioimmunoassay kit for measurement of human osteocalcin was validated for use in horses. For accurate measurement of equine serum osteocalcin, blood samples may be collected at a temperature between 20 and 25 C, then centrifuged within 90 minutes; serum may be stored at -20 C in plastic tubes for up to 26 weeks. Serum may be thawed and refrozen up to 5 times without significant change in measured equine serum osteocalcin concentration. Assay sensitivity was 0.16 ng/ml. Recovery of bovine osteocalcin standard added to equine serum was linear. Intra-assay coefficient o...
Roncada P, Tomasi L, Montesissa C, Grossi G, Stracciari GL, Anfossi P.The kinetics of 2 formulations of theophylline were studied in horses. In an initial cross-over study (Phase I) serum concentration-time curves were determined for granulated and microencapsulated theophylline after a single oral administration (5 mg/kg bwt). In Phase II microencapsulated theophylline was administered at 5 mg/kg bwt/12 h for 10 days at feeding time, as in normal clinical practice. Although no significant differences between the 2 preparations were found with respect to the main kinetic parameters, the microencapsulated form was more evenly and completely absorbed from the dige...
Geiser DR, Andrews FM, Rohrbach BW, White SL, Maykuth PL, Green EM, Provenza MK.Blood ionized calcium (Ca2+) and pH; plasma lactate concentrations; and total protein, total calcium (CaT), albumin, and phosphorus concentrations in serum were determined in 40 healthy horses before (T1), at the finish line (T2), and 10 minutes after the finish (T3) of the cross-country phase of a 3-day-event competition. Mean (+/- SEM) Ca2+ concentrations decreased from 6.22 +/- 0.04 mg/dl at T1 to 5.04 +/- 0.07 mg/dl at T2 (P < or = 0.05). This decrease was accompanied by a nonsignificant increase in CaT between T1 and T2. The mean (+/- SEM) percent ionization of calcium decreased significa...
Basova NE, Kormilitsin BN, Perchenok AIu, Rozengart EV, Saakov VS, Suvorov AA.There was studied action of aliphatic alcohols (ethanol, propanol, isopropanol, n-butanol, isobutanol, secbutanol, tretbetanol) and pH on various kinds of reactional capability the serum cholinesterase. At the alcohols-affected inhibition of the cholinesterase hydrolytic activity, the determining role was played not the total number carbon atoms in the alcohol molecule, but by the "effective length" of the carbohydrate chain. The fact that the presence of alcohols did not affect parameters of the reverse cholinesterase inhibition with onium ions tetramethylammonium and choline allows suggestin...
Izzati MRNZ, Noraniza MA, Adamu L, Rasedee A.Endurance horses are usually eliminated from the race due to lameness, metabolic ailments or technical reasons. The purpose of the study was to determine the validity and reliability of the metabolic disorder index (MDI) in predicting metabolic eliminations in endurance horses during an endurance race. Fifty-four endurance horses competing on two local endurance tracks were involved in the study. Blood samples were collected a day prior to the event to determine packed cell volume (PCV), chloride (Cl), interleukin-6 (IL-6), creatine kinase (CK) and glutathione reductase (GR) concentrations fro...
Ramsay EC, Geiser D, Carter W, Tobin T.To compare the effect of orally delivered detomidine on head posture when administered alone or in combination with two different food items, and to determine the serum concentrations of detomidine after oral delivery. Methods: Prospective randomized experimental study. Methods: Fifteen adult grade mares weighing 328-537 kg. Methods: The horses were randomly assigned to one of the three treatment groups (five horses each). The groups were given detomidine (0.06 mg kg): alone; mixed with 3 mL of an apple sauce and gum mixture; or mixed with 3 mL molasses. Head droop, measured before treatment a...
Hubbard CD, Shoupe TS.A transient phase for the hydrolysis of indophenyl acetate by the commercial preparation of horse serum cholinesterase was observed on a stopped-flow spectrophotometer. It was found that the transient process is a reaction of the ester with a major component of the preparation and is not caused by the serum cholinesterase enzyme. This noncholinesterase component was isolated and the dependence of its concentration and that of the ester upon the transient liberation of the indophenolate ion were determined. Studies with the isolated component and subsequent analyses have led to the tentative id...
Camp CJ, Leid HW.Extracts of Onchocerca cervicalis, an equine parasite, were incubated with radiolabeled equine neutrophils and neutrophil migration was assessed for factors derived from the parasite itself or for host-derived factors after incubation of these same parasite extracts with equine serum. No stimulus for cell migration was observed in saline extracts of adult worms, uterine microfilariae, or skin microfilariae at any dosage tested. However, after incubation of saline extracts with fresh normal equine sera a marked stimulus for neutrophil migration was observed. Ablation of this biologic activity w...
Collins ND, LeRoy BE, Vap L.Extremely high bicarbonate (HCO3-) and anion gap values were measured in two horses and a calf using the Hitachi 911 automated serum biochemistry analyzer. All three animals had severe muscle disease as evidenced by markedly increased aspartate aminotransferase and creatine kinase activities. Laboratory error was suspected as the source of the increased HCO3- because values calculated from blood gas analysis were normal. It was hypothesized that increased serum lactate dehydrogenase (LDH) activity and pyruvate concentration overwhelmed the oxamate LDH inhibitor in the enzymatic HCO3- assay, re...
Brumbaugh GW, Thomas WP, Enos LR, Kaneko JJ.Digoxin was administered orally and intravenously to seven healthy adult mares and geldings in two separate trials. At a dose of 44 microgram digoxin/kg body weight, the oral study was characterized by an absorption phase with a mean (+/- 1 standard deviation) peak serum digoxin concentration of 2.21 ng/ml (+/- 0.45) at a mean of 2.29 h (+/- 1.52) after administration. A second rise in serum digoxin concentration started about 6-8 h after administration and extended to about 20 h after administration. The mean bioavailability (F) was 23.38% (+/- 5.96). At a dose of 22 microgram digoxin/kg body...
Gu XL, Dai FY, Xiao X, Li GZ, Zhang LM, Qu WJ.The effect of Ageratina adenophora on pathological characteristics of the liver and lungs as well as serum biochemical parameters in horses were investigated. Ten horses without ingestion history of Ageratina adenophora were classified into the control group, and 10 poisoned but survived horses with 3 months ingestion history were set as the case group. Results showed that serum AST, ALT, ALP, magnesium and phosphorus were elevated significantly, while creatinine was decreased remarkably. Hematoxylin and eosin staining of liver tissues showed diffuse swelling or destruction of hepatocytes, nar...
Monkos K.This paper presents the results of viscosity determinations on aqueous solutions of equine, porcine and rabbit serum albumin over a wide range of concentrations and at temperatures ranging from 5 degrees C to (42-45) degrees C. The results are compared with human and bovine serum albumin previously studied. Viscosity-temperature dependence is discussed on the basis of the modified Arrhenius formula. The effective specific volume, the activation energy and entropy of viscous flow for all investigated albumins are compared. Viscosity-concentration dependence, in turn, is discussed on the basis o...
Dirikolu L, Lehner AF, Hughes C, Karpiesiuk W, Camargo FC, Harkins JD, Woods WE, Bosken JM, Boyles J, Troppmann A, Fisher M, Tobin T.Furosemide is a potent loop diuretic used for the prevention of exercise-induced pulmonary hemorrhage in horses. This drug may interfere with the detection of other substances by reducing urinary concentrations, so its use is strictly regulated. The regulation of furosemide in many racing jurisdictions is based on paired limits of urinary SG (100 ng/ml). To validate this regulatory mechanism, a liquid chromatography/mass spectrometry/mass spectrometry method employing a solid-phase extraction procedure and furosemide-d5 as an internal standard was developed. The method was used to determine th...
Jacobi S, Townsend WM, Bolin CA.To evaluate whether equine serum administered via a simulated subpalpebral lavage system (SPL) supports proliferation of Streptococcus zooepidemicus or Pseudomonas aeruginosa within the tubing. Methods: A sterile i.v. catheter with injection cap was inserted into sterilized silicone tubing (Mila). To mimic an SPL within the dorsal conjunctival fornix, the tubing was secured to an elevated platform. The tip of the tubing extended from the platform into a vial containing culture medium just inoculated with approximately 1.5 x 10(8) CFU/mL P. aeruginosa or S. zooepidemicus. To mimic administratio...
Grosskopf JF, Smuts EG.Blood was collected from 28 zebra mare (Equus burchellia antiquorum) immediately after being shot in the Kruger National Park. The serum was separated within two hours after collection and then stored at -15 degrees C for later assay. Of these, thirteen selected samples were tested for gonadotrophic activity. The stage of pregnancy was determined from a foetal growth curve. Blood samples from pregnant horse mares were collected by venipuncture. Nine mares were sampled. Seven blood samples at different stages of pregnancy were collected from one mare, four from another and only one sample each ...
