Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
Whitton RC, Mirams M, Mackie EJ, Anderson GA, Seeman E.Bone remodelling is inhibited by high repetitive loading. However, in subchondral bone of racehorses in training, eroded surface doubled in association with fatigue fracture and there was greater surrounding trabecular bone volume suggesting trabecular modelling unloads the bone focally, allowing damage repair by remodelling. Background: Remodelling replaces damaged bone with new bone but is suppressed during high magnitude repetitive loading when damage is most likely. However, in cortical bone of racehorses, at sites of fatigue fracture, focal porosity, consistent with remodelling, is observ...
Olive J, Vila T, Serraud N.To compare navicular bone marrow lesion (BML) conspicuity in the feet of horses as determined via 2 fat-suppressed MRI techniques, including standard short tau inversion recovery (STIR) and inversion recovery gradient echo (IRGE). Methods: Feet (n = 150) of horses with lameness referable to the distal portion of the digit. Methods: STIR and IRGE sequences were obtained prospectively in all feet with a standing low-field equine MRI system. Presence of a BML was ascertained by identification of a characteristic combination of marrow alterations in T1-weighted, T2*-weighted, T2-weighted, and STIR...
Renier AC, Kass PH, Magdesian KG, Madigan JE, Aleman M, Pusterla N.To determine clinical, laboratory analysis, and necropsy findings for equids with oleander toxicosis and to identify factors associated with outcome. Methods: Retrospective case series. Methods: 30 equids. Methods: Medical records of equids with detectable concentrations of oleandrin in serum, plasma, urine, or gastrointestinal fluid samples and equids that had not received cardiac glycoside drugs but had detectable concentrations of digoxin in serum were identified via a medical records database search. Descriptive statistics were calculated for medical history, physical examination, laborato...
Van Erck-Westergren E, Franklin SH, Bayly WM.Given that aerobic metabolism is the predominant energy pathway for most sports, the respiratory system can be a rate-limiting factor in the exercise capacity of fit and healthy horses. Consequently, respiratory diseases, even in mild forms, are potentially deleterious to any athletic performance. The functional impairment associated with a respiratory condition depends on the degree of severity of the disease and the equestrian discipline involved. Respiratory abnormalities generally result in an increase in respiratory impedance and work of breathing and a reduced level of ventilation that c...
Ramos-Vara JA, Frank CB, DuSold D, Miller MA.The immunoreactivity of PNL2, Melan A, and protein gene product (PGP) 9.5 was compared with that of S100 protein in 50 formalin-fixed, paraffin-embedded equine melanocytic neoplasms. PNL2, PGP 9.5, and S100 protein were detected in all 50 neoplasms; none expressed Melan A. PNL2 was not expressed in 62 nonmelanocytic tumors (equine sarcoids, schwannomas, carcinomas, sarcomas, endocrine tumors, sex-cord stromal tumors, germ cell tumors, and leukocytic tumors) or in normal tissues other than epidermis. In summary, antibody PNL2 is a sensitive marker of equine melanocytic neoplasms and is more spe...
Williams KJ, Robinson NE, Defeijter-Rupp H, Millerick-May M, Stack A, Hauptman J, Derksen FJ.Exercise-induced pulmonary hemorrhage (EIPH), which has been reported in humans and a variety of domestic animals following strenuous exercise, is most often documented in racehorses. Remodeling of pulmonary veins (VR) in equine EIPH was recently described, suggesting that it contributes to the pathogenesis of the disease. The cause of VR is unknown. We tested the hypothesis that the development of VR follows pulmonary blood flow distribution, preferentially occurring in the caudodorsal lung region. Furthermore, we hypothesized that VR underpins development of the other lesions of EIPH patholo...
Hampson BA, de Laat MA, Mills PC, Walsh DM, Pollitt CC.It has been proposed that the feral horse foot is a benchmark model for foot health in horses. However, the foot health of feral horses has not been formally investigated. Objective: To investigate the foot health of Australian feral horses and determine if foot health is affected by environmental factors, such as substrate properties and distance travelled. Methods: Twenty adult feral horses from five populations (n = 100) were investigated. Populations were selected on the basis of substrate hardness and the amount of travel typical for the population. Feet were radiographed and photographed...
Khan A, Khan MS, Avais M, Ijaz M, Ali MM, Abbas T.The prevalence of Balantidium coli among donkeys in Lahore and adjoining areas was surveyed and a trial conducted to determine the efficacy of two antiprotozoal drugs: secnidazole (Dysen Forte) and Kalonji (Nigella sativa). Four-hundred donkeys were examined, and 73 (18.3%) were found positive for Balantidium coli. A slight decrease in PCV and an increase in Hb values of infected donkeys were found after antiprotozoal treatment. Secnidazole was 89.5% effective for the treatment of equine balantidiasis compared to 40.0% for Nigella sativa. This is the first report of balantidiasis in equines fr...
Klaus C, Hörügel U, Hoffmann B, Beer M.During a routine examination of 130 horse sera from 13 herds in Thuringia one TBEV antibody positive serum - with a very high titre - could be detected. The horse had been bought from a holding in Bavaria, and was reported to have clinical signs that may have been caused by a TBEV infection. To identify the source of the suspected TBEV infection, ticks from the surroundings of the barn in Thuringia as well as horse sera and ticks from two herds in Bavaria were examined. In the holding in Bavaria, where the horse was kept before, two out of ten horse sera were found to be TBEV antibody positive...
Cafarchia C, Figueredo LA, Otranto D.Among diseases of horses caused by fungi (=mycoses), dermatophytosis, cryptococcosis and aspergillosis are of particular concern, due their worldwide diffusion and, for some of them, zoonotic potential. Conversely, other mycoses such as subcutaneous (i.e., pythiosis and mycetoma) or deep mycoses (i.e., blastomycosis and coccidioidomycosis) are rare, and/or limited to restricted geographical areas. Generally, subcutaneous and deep mycoses are chronic and progressive diseases; clinical signs include extensive, painful lesions (not pathognomonic), which resemble to other microbial infections. In ...
Greve L, Dyson SJ.We have observed saddle slip consistently to one side because of a crooked rider, an ill-fitting saddle, asymmetry in a horse's thoracolumbar shape and lameness. Currently, there are no objective data to permit assessment of the relative importance of each factor. Objective: To document the frequency of occurrence of saddle slip in horses with hindlimb lameness compared with other horses. To describe the effect of lameness characteristics and grade, the abolition of lameness by diagnostic analgesia, breed, size, thoracolumbar shape and symmetry and the rider's weight. Methods: One hundred and ...
Burton AJ, Giguère S, Sturgill TL, Berghaus LJ, Slovis NM, Whitman JL, Levering C, Kuskie KR, Cohen ND.Macrolide and rifampin resistance developed on a horse breeding farm after widespread use was instituted for treatment of subclinical pulmonary lesions in foals. Resistance occurred in 6 (24%) of 25 pretreatment and 8 (62%) of 13 (62%) posttreatment isolates from affected foals. Drug-resistant isolates formed 2 distinct genotypic clusters.
Mann RA, Fegan M, O'Riley K, Motha J, Warner S.Virus was detected in the central nervous system (CNS) tissue of 11 horses from Victoria that died displaying neurological symptoms during an outbreak of disease in Australia in 2011. Five horses were identified as being infected with Murray Valley encephalitis virus (MVEV) and 6 as being infected with West Nile virus subtype Kunjin (WNV(KUN)). Analysis of partial sequence information from the NS5 and E genes indicated that the MVEVs within the samples were highly homogenous and all belonged to lineage I, which is enzootic to the tropical regions of northern Australia. Likewise, analysis of pa...
Winfield LD, White SD, Affolter VK, Renier AC, Dawson D, Olivry T, Outerbridge CA, Wang YH, Iyori K, Nishifuji K.To describe the clinical, histological and immunological findings of an equine case of pemphigus vulgaris, including the demonstration of antidesmoglein (anti-Dsg) autoantibodies. Methods: The diagnosis of pemphigus vulgaris was confirmed in a 9-year-old Welsh pony stallion with both direct and indirect immunofluorescence and immunoprecipitation studies, the latter identifying circulating anti-Dsg3 IgG. Treatment with immunosuppressive medications was initiated. Lesions were seen in the perineal area, sheath, mane, tail, eyelids, coronary bands and mucosa of the mouth and oesophagus. Initial c...
Verwilghen DR, Janssens S, Busoni V, Pille F, Johnston C, Serteyn D.Few reports are available on the relationship between developmental orthopaedic diseases (DOD) and future performances in Warmblood horses. Objective: To investigate the relationship between performance and the presence of DOD lesions. Methods: Records of Warmblood stallions for which radiographic and performance data were available were collected. Showjumping performances were expressed as scores derived from the final ranking of horses in each competition. These scores are available in an established performance database. The relationship between radiographic findings and both performance sc...
Bergström K, Bengtsson B, Nyman A, Grönlund Andersson U.An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) infections in horses in Sweden raised questions concerning the risk posed by horses to their surroundings following MRSA infections. This initiated a longitudinal study to investigate how long MRSA-infected horses remained positive and to test the sensitivity of different anatomical sampling sites for detection of MRSA. Between October 2008 and June 2010, 9 of 15 horses notified as having MRSA-infected wounds fitted the case criteria for the study. The cases were sampled at five anatomical sites (nostrils, corner of mouth, paste...
Sloet van Oldruitenborgh-Oosterbaan MM, Grinwis GC.Equine sarcoidosis may present as a generalized or localized exfoliative dermatitis and/or as a granulomatous inflammation of multiple organs. Objective: To report the clinical signs, diagnosis, treatment and outcome for 22 horses with histologically confirmed sarcoidosis. Methods: Twenty-two horses of different breeds, between 3 and 17 years of age. Methods: Diagnosis was based on clinical signs and histopathological findings. Results: The following three forms of equine sarcoidosis were identified: generalized (13.6%), partially generalized (18.2%) and localized (68.2%). High-dose systemic c...
Innerå M, Petersen AD, Desjardins DR, Steficek BA, Rosser EJ, Schott HC.Pituitary pars intermedia dysfunction (PPID) in older equids is commonly recognized by a long hair coat that fails to shed. Objective: The aim of this study was to compare hair follicle stages in PPID-affected horses with excessively long hair coats with the stages of normal aged horses (controls) and to compare hair follicle stages in PPID-affected horses after 6 months of treatment with pergolide mesylate with those of control horses. Methods: Eight PPID-affected horses and four normal, age-matched, control horses. Methods: Skin biopsies were collected from the neck and rump of PPID-affected...
Baptista C, Lopes MS, Tavares AC, Rojer H, Kappmeyer L, Mendonça D, da Câmara Machado A.Equine piroplasmosis is a tick-borne disease of equids that is often caused by the parasite Theileria equi. We applied competitive ELISA (cELISA) and nested PCR diagnostic methods to detect this parasite in horses by screening 162 samples from mainland Portugal where the parasite is endemic, and 143 from the Azores representing both native and imported horse populations. We found that 2.8% of the Azorean samples tested positive exclusively by cELISA, 1.4% tested positive only by nested PCR, and 9.1% tested positive using both tests. Samples from the native Terceira Pony population were negativ...
Laus F, Veronesi F, Passamonti F, Paggi E, Cerquetella M, Hyatt D, Tesei B, Fioretti DP.In order to investigate the prevalence of tick-borne diseases, equine piroplasmosis, equine granulocytic anaplasmosis and Lyme borreliosis in Central Italy, blood samples from 300 horses were analyzed for the presence of antibodies against Babesia caballi, Theileria equi, Anaplasma phagocytophilum and Borrelia burgdorferi using the IFAT. The blood samples were also subjected to PCR assays in order to detect pathogen DNA. A total of 78 (26.0%) and 123 (41.0%) horses were found to be seropositive for B. caballi and T. equi, respectively, while 41 (13. 4%) and 21 (7.0%) horses were, respectively,...
Shih A.Cardiac output (CO) is the volume of blood pumped out by the heart in 1 minute. Monitoring of CO can guide therapy and improve clinical outcome in critically ill patients and during anesthesia. Although there is increasing research into clinically useful methods of monitoring CO in equine patients, there are limitations to the available methods. There are 4 basic methods of measuring CO: (1) indicator methods, (2) a derivation of the Fick principle, (3) arterial pulse wave analysis, and (4) imaging diagnostic techniques. This article discusses the importance of CO, available technology, and ch...
Equine infectious anaemia in Europe Equine herpesvirus in the UK Summary of surveillance testing, July to September 2012 These are among matters discussed in the quarterly equine disease surveillance report for July to September 2012, prepared by Defra, the Animal Health Trust and the British Equine Veterinary Association.
Shin SH, Yoon JH, Yahng SA, Lee SE, Cho BS, Eom KS, Kim YJ, Lee S, Min CK, Kim HJ, Cho SG, Kim DW, Min WS, Park CW, Lee JW.Antithymocyte globulin (ATG) is the drug of choice for immunosuppressive therapy (IST) in patients with severe aplastic anemia (SAA) ineligible for allogeneic stem cell transplantation. Recently, rabbit ATG with cyclosporine A has been used as a first-line IST regimen in patients with SAA because of unavailability of horse ATG. We retrospectively analyzed adult SAA patients who were treated with horse ATG (n=46) or rabbit ATG (n=53) between Feb 2001 and May 2010 to compare hematologic response and survival. Overall response rates at 3, 6, 12, and 18 months were similar in both the horse and ra...
Hallowell GD, Bowen M.The objectives were to determine and assess the reliability of criteria for identification of aortic valve prolapse (AVP) using echocardiography in the horse. Results: Opinion of equine cardiologists indicated that a long-axis view of the aortic valve (AoV) was most commonly used for identification of AVP (46%; n=13). There was consensus that AVP could be mimicked by ultrasound probe malignment. This was confirmed in 7 healthy horses, where the appearance of AVP could be induced by malalignment. In a study of a further 8 healthy horses (5 with AVP) examined daily for 5 days, by two echocardiog...
You Y, Uboh CE, Soma LR, Guan F, Taylor D, Li X, Liu Y, Chen J.A method involving ultra high-performance liquid chromatography-tandem mass spectrometry was developed and validated for the analysis of capsaicin and dihydrocapsaicin in equine plasma. The analytes were recovered from plasma by liquid-liquid extraction using methyl tert-butyl ether and separated on a sub-2 micron column. The mobile phase was composed of 2 mM ammonium formate and methanol. A triple quadrupole mass spectrometer was used to detect the analytes in positive electrospray ionization mode with selected reaction monitoring. The limits of detection, quantification and confirmation for ...
Bickers RJ, Blackford JT, Eiler H, Rohrbach B.To compare bursting strength, time of construction, and cost of a closed one-stage, stapled functional end-to-end jejunojejunostomy (FEE) with a stapled side-to-side jejunojejunostomy (STS). Methods: Experimental, randomized block design. Methods: Seven adult horses without gastrointestinal disease. Methods: The jejunum was isolated, and three FEE, three STS, and three control segments were created in each horse using a randomized block design. Anastomosis time was recorded. The intraluminal pressure at failure and mode of failure were recorded. Length at failure was measured on digitized imag...
Clode AB.The following article briefly discusses the pathogenesis of infectious keratitis in the horse, followed by discussion of management and pharmacological aspects to be considered when devising a therapeutic protocol for affected patients.
McKenzie HC, Geor RJ.Nutritional support of the foal can be challenging because of the constant changes in nutritional requirements and dietary composition during the transition from neonate to weanling. Additional complexity arises because of dilemmas regarding the means and route of delivery of nutrition to the foal, and the possibility that metabolic dysfunction may impair the ability of the foal to use nutrients appropriately. This article provides practical information on enteral and parenteral nutritional support of sick neonatal foals. The potential benefits of a conservative, hypocaloric feeding strategy, ...
Haffner JC, Eiler H, Hoffman RM, Fecteau KA, Oliver JW.Sustained dexamethasone administration to horses results in insulin resistance, which may predispose them to laminitis. A single dose of dexamethasone is commonly used as a diagnostic aid, yet the effect of a single dose of dexamethasone on glucose homeostasis in horses is not well defined. The objective of this study was to characterize the change in glucose dynamics over time in response to a single dose of dexamethasone. A combined glucose-insulin tolerance test (CGIT) was performed on 6 adult geldings before and at 2, 24, and 72 h postdexamethasone (40 microg/kg of BW, i.v.); a minimum of ...
Piza AS, Pereira AR, Terreran MT, Mozzer O, Tanuri A, Brandão PE, Richtzenhain LJ.We used a p26 recombinant protein (p26r) from equine infectious-anemia virus (EIAV) expressed in Escherichia coli as antigen to standardize an agar-gel immunodiffusion (AGIDp26r) test and an indirect ELISA (ELISAp26r) for the detection of antibodies against EIAV in 720 equine sera from Brazil. We evaluated the tests's relative diagnostic sensitivities (relSe) and relative diagnostic specificities (relSp) against a commercial AGID kit (Idexx, USA). We used three sera panels: panel A--196 AGID-negative sera from an AIE non-endemic controlled area; panel B--194 AGID-negative sera from an AIE ende...
Pennick KE, McKnight CA, Patterson JS, Latimer KS, Maes RK, Wise AG, Kiupel M.Immunohistochemistry (IHC) and in situ hybridization (ISH) can be used either to detect or to differentiate between Eastern equine encephalitis virus (EEEV) and West Nile virus (WNV) within formalin-fixed, paraffin-embedded (FFPE) brain tissue of horses. To compare the diagnostic sensitivity and specificity of ISH and IHC, FFPE brain tissue from 20 EEEV-positive horses and 16 WNV-positive horses were tested with both EEEV and WNV oligoprobes and EEEV- and WNV-specific antibodies. Reverse transcription polymerase chain reaction (RT-PCR) for detection of EEEV and WNV was used as the gold standar...
McGuire TC, Pollara B, Moore JJ, Poppie MJ.Foals with combined immunodeficiency had normal levels of purine salvage pathway enzymes, including adenosine deaminase, nucleoside phosphorylase, and xanthine oxidase.
Miller FL, Bellaw JL, Lyons ET, Nielsen MK.Strongyloides westeri is a threadworm parasite found in the small intestine mainly in foals at up to about 4 months of age. This parasite is associated with small intestinal enteritis and diarrhea as well as skin irritation and a clinical syndrome called "frenzied behavior" due to percutaneous invasion. The aim of this study was to investigate S. westeri parasite burdens in age groups older than the initial lactogenic transmission phase. Secondary aims were to examine the impact of host age and gender on worm burden and egg output in naturally infected foals. Thirteen foals were enrolled in th...
Smets K, Shaw DJ, Deprez P, Vercruysse J.Between October 1996 and May 1997, 94 horses which were suspected of being infected with strongyles were examined clinically, and samples of faeces were examined for strongyle eggs and cyathostome larvae (L4) and adults. Blood samples were monitored for total protein, albumin and beta-globulins. In 28 of the horses (30 per cent) cyathostome L4 and adults were detected in the faeces, and were significantly associated with the horses' condition, the occurrence of diarrhoea, with lower concentrations of total protein and albumin, and with higher percentages of beta-globulin. Thirty-four of the ho...
Dembek KA, Johnson LM, Timko KJ, Minuto JS, Hart KA, Barr BS, Toribio RE.The hypothalamic-pituitary-adrenal axis regulates the response to sepsis-associated stress. Relative adrenal insufficiency or adrenocorticotropic hormone (ACTH):cortisol imbalance, defined as a poor cortisol response to administration of ACTH, is common and associated with death in hospitalized foals. However, information on other adrenal steroid response to ACTH stimulation in sick foals is minimal. Objective: To investigate the response of multiple adrenocortical steroids to administration of ACTH in foals. Methods: Hospitalized (n = 34) and healthy (n = 13) foals. Methods: In this prospecti...
Carmalt JL, Pimentel KL.Definitive diagnosis of equine temporomandibular joint osteoarthritis (TMJ-OA) may require advanced diagnostic imaging. Arthroscopy is a modern, minimally invasive, diagnostic, and treatment modality. Standing arthroscopic treatment of joint disease is a relatively recent advance in equine surgery, despite which there are few published comparisons between the available arthroscopic systems. Unassigned: To compare and contrast two arthroscopic systems for assessing the equine temporomandibular joint compartments in cadavers and standing horses. Unassigned: Experimental study. Unassigned: Phase ...
Habibi G, Esmaeilnia K, Hablolvarid MH, Afshari A, Zamen M, Bozorgi S.Equine piroplasmosis (EP) is the cause of persistent tick-borne infection with no symptoms, but the most important problem of EP is due to the persistent carrier state. Carrier animals to Babesia (Theileria) equi (Laveran 1901) and B. caballi (Nuttall, 1910) infestation could be identified by extremely sensitive PCR-based method. The purpose of this study was to identify the causative agents of equine piroplasmosis based on molecular and microscopic assays in equids from Kurdistan Province, Iran. Methods: Thirty one horse and mule blood samples were used with history of living in Kurdistan Pro...
Pille F, Martens A, Schouls LM, Dewulf J, Decostere A, Vogelaers D, Gasthuys F.The objectives of the present study were to evaluate the accuracy of broad range 16S rRNA gene PCR compared to bacterial culture for the detection of synovial infection in horses. The study included 57 synovial fluid samples from horses with presumed synovial infection and a control group consisting of 31 synovial fluid samples originating from clinically normal horses and horses with aseptic synovial inflammation. All samples were analysed by 16S PCR with reverse line blot (RLB) hybridisation. Synovial fluid samples were cultured using conventional agar plate methods (APM) and/or blood cultur...
Bellier S, Cordonnier N.The goal of this article is to present the technical aspects and the applications of the blood cells examination and haemostasis in dogs and cats. Technical realisation of blood counts, cytology of normal and abnormal blood cells and significance of the pathologic cell counts are successively treated. Distinctive features of cytology and cell counts in herbivores, horses and cattle, are detailed in a separate chapter.Difficulties of veterinary haematology lie in qualitative and quantitative differences between blood cells of various animal species.Bone marrow cells exploration is not performed...
Pittaway CE, Lawson AL, Coles GC, Wilson AD.Infection of horses with Anoplocephala perfoliata induces a severe inflammatory reaction of the caecal mucosa around the site of parasite attachment adjacent to the ileocecal valve. Lesions show epithelial erosion or ulceration of the mucosa with infiltration by eosinophils, lymphocytes and mast cells leading to oedema, gross thickening and fibrosis of the caecal wall. Despite this evidence of an inflammatory reaction to A. perfoliata within the mucosa of the caecum there is little information about the nature of the local immune response to A. perfoliata. An ELISA which assays serum IgG(T) an...
Perrucci S, Buggiani C, Sgorbini M, Cerchiai I, Otranto D, Traversa D.Cryptosporidium infection was molecularly investigated in mares and in their neonatal foals for which the occurrence of foal heat diarrhoea was also assessed. Thirty-seven mare/foal pairs were included in the study. All foals were born in the same stud farm during 2006-2008 breeding seasons. Two faecal samples, one prior to and one after delivery were collected from each mare, whereas three faecal samples were taken from each foal, i.e. at 8, 10 and 12 days of age. All samples (74 from mares and 111 from foals) were divided into two aliquots, one of which was examined for the presence of Crypt...
Huber L, Giguère S, Berghaus LJ, Hanafi A, Ryan C.Rhodococcus equi, a soil saprophyte, is a common cause of pneumonia in foals and a frequent opportunistic pathogen in immunosuppressed people. Because it is widespread in the environment, R. equi can be detected in the feces of most horses. However, the exact timing and rate of shedding relative to infection is unknown. The objectives of this study were to quantify shedding of R. equi in mares and foals after experimental infection of foals with 2 different inocula and to determine the effect of composting on concentrations of R. equi in contaminated bedding. Foals were infected intratracheall...
van der Kolk JH, Nachreiner RF, Refsal KR, Brouillet D, Wensing T.Our objectives were to 1) establish ionised calcium (ICa), C-terminal PTH and biologically active PTH (intact molecule) concentrations in blood from normal horses, 2) examine the stability of ionised calcium and acid-base values in stored equine heparinised blood and serum and 3) check the applicability of the formulas based on these parameters in certain disease states. Mean +/- s.d. % ionised calcium in heparinised blood of normal Warmbloods was 51 +/- 2.7 (n = 20) of total calcium, range 1.45-1.75 mmol/l (n = 15) at Michigan State University and 1.43-1.69 mmol/l (n = 20) at Utrecht Universi...