1
|
Dirikolu L, Waller P, Malveaux K, Lucas CH, Lomnicka I, Pourciau A, Bennadji H, Liu CC. Total Carbon Dioxide (TCO 2) Concentrations in Thoroughbred and Quarter Racehorses in Louisiana. J Equine Vet Sci 2023; 121:104220. [PMID: 36621701 DOI: 10.1016/j.jevs.2023.104220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 01/03/2023] [Accepted: 01/03/2023] [Indexed: 01/09/2023]
Abstract
The TCO2 (total carbon dioxide) test is performed on the blood of racehorses as a means of combatting the practice of administering alkalizing agents. This study evaluated serum TCO2 concentrations and factors influencing concentration of TCO2 in Thoroughbred and Quarter Horses. The normality of data were evaluated with a Shapiro-Wilk test. Mann-Whitney tests and Kruskal-Wallis tests were used against different effects. When a fixed effect was detected, Dunn's post-hoc comparisons were performed. The median pre-race serum TCO2 concentration (32.20 mmol/L (interquartile range (IQR): 30.80-33.50)) was higher than that of post-race samples (26.70 mmol/L (IQR: 24.55-29.25)) (P < .0001). The median TCO2 concentrations in pre-race samples were different between Thoroughbred (32.40 mmol/L (IQR: 30.90-33.60)) and Quarter Horses (31.30 mmol/L (IQR: 30.00-32.50)) (P < .0001). The median pre-race TCO2 concentrations were 32.75 (IQR: 31.40-33.90), 31.40 (IQR: 29.80-32.80), 32.50 (IQR: 31.20-33.88), and 31.60 (IQR 30.00-32.70) mmol/L in racehorses at Fair Grounds, Louisiana Downs, Delta Downs, and Evangeline Downs racetracks, respectively (P < .0001). The total serum TCO2 concentrations in Thoroughbred and Quarter Horse racehorses were affected by seasonal temperature variation (P < .0001). A smaller sample size was available for post-race samples (n = 205) and Quarter Horse pre-race samples (n = 351). The results of this study indicated that the breed, seasonal temperature variation, pre-race or post-race sampling, and track location are strongly correlated to total TCO2 concentrations. It was not clear whether the statistically significant differences in TCO2 levels among racetracks in Louisiana were due to location of racetracks and/or seasonal temperature variation.
Collapse
Affiliation(s)
- Levent Dirikolu
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA.
| | - Pamela Waller
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| | - Kesha Malveaux
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| | - Cam H Lucas
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| | - Izabela Lomnicka
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| | - Ashley Pourciau
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| | - Hayat Bennadji
- Equine Medication Surveillance Laboratory, Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| | - Chin-Chi Liu
- Department of Veterinary Clinical Services, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA
| |
Collapse
|
2
|
Lindinger MI. Total Carbon Dioxide in Adult Standardbred and Thoroughbred Horses. J Equine Vet Sci 2021; 106:103730. [PMID: 34670689 DOI: 10.1016/j.jevs.2021.103730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 08/02/2021] [Accepted: 08/08/2021] [Indexed: 10/20/2022]
Abstract
The TCO2 (total carbon dioxide) test is performed on the blood of racehorses as a means of combatting the practice of administering alkalizing agents for the purpose of enhancing performance. The purposes of this review are to present an overview of the factors contributing to TCO2 and to review the literature regarding TCO2 in adult Standardbred and Thoroughbred horses to demonstrate the range of variability of TCO2 in horses. Most of the research published on the topic of TCO2 or bicarbonate measurement in racehorses was accessed and reviewed. PubMed and Google Scholar were the primary search engines used to source the relevant literature. The main physicochemical factors that contribute to changes in TCO2 in horses at rest are changes in strong ions concentration, followed by changes in weak acid (i.e. plasma albumin) concentrations. There is a wide normal distribution of TCO2 in horses ranging from 23 mmol/L to 38 mmol/L. Independent of administration of alkalizing agents, blood TCO2 is affected mainly by feeding, time of day (diurnal variation), season and exercise. There are few studies that have reported hour-by-hour changes in TCO2. Racehorse population studies suffer from lack of validation regarding whether or not a horse was administered an alkalizing agent. It is concluded that the normal range of TCO2 in non-alkalized Standardbred and Thoroughbred horses is significantly wider than has been appreciated, that periods of elevated TCO2 appear to be normal for many horses at rest, and that a TCO2 test alone is not definitive for the purposes of determining of an alkalizing agent has been administered to a horse.
Collapse
|
3
|
Buckley P, Buckley DJ, Freire R, Hughes KJ. Pre-race and race management impacts serum muscle enzyme activity in Australian endurance horses. Equine Vet J 2021; 54:895-904. [PMID: 34601756 PMCID: PMC9545901 DOI: 10.1111/evj.13519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 07/27/2021] [Accepted: 09/23/2021] [Indexed: 11/28/2022]
Abstract
Background Marked increases in serum muscle enzyme activity can occur in endurance horses but the diagnostic certainty in predicting cases of myopathy is unclear. Improved understanding of horse management effects on serum muscle enzyme activity as markers of muscle health would assist interpretation of serum muscle enzyme activity and guide management to reduce myopathy risk. Objectives To investigate associations between serum muscle enzyme activity and management factors in endurance horses. Study design Cross‐sectional study. Methods One hundred endurance horses competing in four endurance events (offering distances of 20‐120 km) in south‐eastern Australia were observed. Data were collected from official horse logbooks, pre‐and post‐race serum samples, an owner questionnaire of pre‐race and race management of horses and the Australian Endurance Riders Association results database. Multivariable linear regression modelling tested associations between management factors and serum muscle enzyme activity. Results First leg speed, distance raced, number of rest days pre‐race, and pre‐race activity of aspartate aminotransferase (AST) and creatine kinase (CK) explained 47.3% of the variance in post‐race CK. As first leg speed increased by 1 km/h, CK activity increased by 25.8% (95% CI 11%‐35%). Race distances >80 km increased post‐race CK activity by 124% (95% CI 116%‐145%). Each additional pre‐race rest day increased post‐race CK activity by 30.5% (95% CI 11%‐42%). Modelling a 10% increase in pre‐race CK and pre‐race AST activity was associated with post‐race CK activity increasing by 7.3% (95% CI 3%‐14.4%) and 8.5% (95% CI 0.3%‐14.2%) respectively. Horses experiencing training distances >40 km and a greater number of rest days prior to race day developed increased pre‐race AST and CK activity respectively. Main limitations Owner questionnaires may be subject to bias. Limited data were available to model ride terrain, horse fitness, ration detail and myopathy. Muscle biopsies were not used to confirm myopathy. Conclusions Nearly half of the variation in post‐race CK activity observed can be attributed to management factors unrelated to myopathy, suggesting increased CK activity may not be pathognomonic for myopathy. We advise caution in relying solely on serum muscle enzyme activity for diagnosis of myopathy until the strength of association between CK and myopathy is further ascertained in future studies.
Collapse
Affiliation(s)
- Petra Buckley
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - David J Buckley
- Clinical Governance Unit, Murrumbidgee Local Health District, Wagga Wagga, New South Wales, Australia
| | - Rafael Freire
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - Kristopher J Hughes
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| |
Collapse
|
4
|
Nelson EA, Sanchez LC, Mallicote MF, Warren LK, Robelen AM, Reuss SM. Effect of a commercial anionic dietary supplement on urinary pH and concentrations of electrolytes and pH in blood of horses. N Z Vet J 2019; 68:60-64. [PMID: 31433953 DOI: 10.1080/00480169.2019.1655498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Aims: To compare urine urinary pH, blood pH and concentration of electrolytes in blood of healthy horses fed an anionic salt supplement to achieve diets with a dietary cation-anion difference (DCAD) of -40 or 0 mEq/kg DM, with horses a fed a diet with a DCAD of 85 mEq/kg DM.Methods: Eight healthy horses received each of three diets in a randomised crossover design. Diets consisted of grass hay and concentrate feed, with a varying amount of an anionic supplement to achieve a DCAD of 85 (control), 0 or -40 mEq/kg DM. They were fed for 14 days each with a washout period of 7 days between. Urine pH was measured daily and blood samples were collected on Days 0, 7 and 14 of each study period for the measurement of pH and concentration of electrolytes.Results: Four horses voluntarily consumed the anionic supplement with their feed, but four horses required oral supplement administration via dose syringe. During the study period mean urine pH was lower in horses fed diets with a DCAD of 0 (6.91; SD 0.04) and -40 (6.83; SD 0.04) mEq/kg DM compared to the control diet (7.30; SD 0.04). Compared with horses fed the control diet, mean urine pH was lower in horses fed the 0 and -40 mEq/kg DM diets on Days 1-12 and 14 (p < 0.05) of the study period. On Day 13 it was only lower in horses fed the -40 mEq/kg DM diet (p < 0.01). Urine pH was similar for horses fed the 0 and -40 mEq/kg DM diets (p = 0.151). The DCAD of the diet had no effect on blood pH, ionised Ca or anion gap. Mean concentrations of bicarbonate in blood were affected by diet (p = 0.049); they were lower when horses were fed the 0 mEq/kg diet relative to the control diet on Day 14.Conclusions and clinical relevance: The anionic supplement reduced urine pH in horses fed diets with a DCAD of 0 or -40 mEq/kg DM compared with 85 mEq/kg DM. However as urinary pH did not fall below pH 6.5, the pH below which calcium carbonate uroliths do not form, this reduction in urine pH is unlikely to be clinically significant. The supplement was variably palatable and showed minimal promise as an effective urinary acidifier at the doses administered in this study.
Collapse
Affiliation(s)
- E A Nelson
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA.,Current Address: San Luis Rey Equine Hospital, Bonsall, CA, USA
| | - L C Sanchez
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - M F Mallicote
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - L K Warren
- Department of Animal Sciences, University of Florida, Gainesville, FL, USA
| | - A M Robelen
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA.,Current Address: Care First Animal Hospital, Cary, NC, USA
| | - S M Reuss
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA.,Current Address: Boehringer Ingelheim Animal Health, Duluth, GA, USA
| |
Collapse
|
5
|
Constable P, Trefz FM, Stämpfli H. Effects of pH and the plasma or serum concentrations of total calcium, chloride, magnesium, l-lactate, and albumin on the plasma ionized calcium concentration in calves. J Vet Intern Med 2019; 33:1822-1832. [PMID: 31059164 PMCID: PMC6639484 DOI: 10.1111/jvim.15509] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 04/12/2019] [Indexed: 11/29/2022] Open
Abstract
Background The plasma ionized calcium concentration (cCa2+) represents the biologically active form of calcium and is the preferred method for evaluating calcium status in animals. Different pH‐corrective equations have been developed for human plasma, but the validity of the equations for bovine plasma is unknown. Hypothesis We hypothesized that pH‐corrective equations for bovine plasma would be similar to those used for human plasma; cCa2+ was dependent on the plasma concentrations of total calcium (cTCa), chloride (cCl), L‐lactate (cLactate), and albumin (cAlbumin); and the in vitro and in vivo cCa2+‐pH relationships would differ. Animals Ten healthy calves (in vitro study), 1426 critically ill calves. Methods The in vitro plasma log10(cCa2+)‐pH relationship was determined by CO2 tonometry of 465 plasma samples. Plasma cCl was altered by equivolume dilution of plasma with 3 electrolyte solutions of different cCl. The in vivo plasma cCa2+‐pH relationship was investigated and validated using clinicopathologic data extracted from the medical records of 950 (model development) and 476 (model validation) critically ill calves. Results pH‐corrective equations for bovine plasma were similar to those used for human plasma. Plasma cCa2+ increased in vitro with increases in plasma cCl. Plasma cCa2+ in critically ill calves was associated with plasma cTCa, blood pH, plasma cCl, serum cMg, and cL‐lactate (R2 = 0.69) but not plasma cAlbumin. Conclusions and Clinical Importance Calculation of cCa2+ from cTCa in calf plasma or serum requires adjustment for at least pH and cCl when 1 or both are outside the reference range.
Collapse
Affiliation(s)
- Peter Constable
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Illinois
| | - Florian M Trefz
- Clinic for Ruminants with Ambulatory and Herd Health Services at the Centre for Clinical Veterinary Medicine, LMU Munich, Oberschleißheim, Germany
| | - Henry Stämpfli
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
6
|
Heer F, Dobenecker B, Kienzle E. Effect of cation-anion balance in feed on urine pH in rabbits in comparison with other species. J Anim Physiol Anim Nutr (Berl) 2017; 101:1324-1330. [PMID: 28299839 DOI: 10.1111/jpn.12653] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 11/08/2016] [Indexed: 10/20/2022]
Abstract
In the present investigation, the impact of diet composition on urine pH in rabbits was compared with previous studies on rabbits, cats, dogs, pigs and horses. A total of 13 dwarf rabbits were fed six different diets with a cation-anion balance (CAB) between -39 and +320 mmol/kg dry matter (DM) using ammonium chloride (NH4 Cl) as an acidifier. CAB was calculated as follows: CAB (mmol/kg DM) = 49.9*Ca + 82.3*Mg +43.5*Na + 25.6*K - 59*P - 62.4*S - 28.2*Cl; minerals in g/kg DM. Urine, faeces and blood were collected. Urine pH ranged from 5.26 ± 0.22 at a CAB of -39 mmol/kg DM to 8.56 ± 0.24 at a CAB of +320 mmol/kg DM. A low CAB in the feed reduced blood pH and blood base excess significantly. Renal excretion of Ca, P, Na and Mg and water was significantly higher in rabbits eating acidifying diets. In comparison with other species, rabbits reacted to acidifying diets in a similar way as cats, dogs and pigs. Rabbits on a mildly alkalizing diet, however, had a trend to higher urine pH than other monogastric species on such diets (cats, dogs, pigs, horses).
Collapse
Affiliation(s)
- F Heer
- Department of Veterinary Science, Ludwig-Maximilians-University, Munich, Germany
| | - B Dobenecker
- Department of Veterinary Science, Ludwig-Maximilians-University, Munich, Germany
| | - E Kienzle
- Department of Veterinary Science, Ludwig-Maximilians-University, Munich, Germany
| |
Collapse
|
7
|
Harris PA, Rivero JLL. Nutritional considerations for equine rhabdomyolysis syndrome. EQUINE VET EDUC 2015. [DOI: 10.1111/eve.12458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- P. A. Harris
- Equine Studies Group; WALTHAM Centre for Pet Nutrition; Waltham-on-the-Wolds, Leicestershire UK
| | - J. L. L. Rivero
- Laboratory of Muscular Biopathology; Department of Comparative Anatomy and Pathological Anatomy; Faculty of Veterinary Sciences; University of Cordoba; Spain
| |
Collapse
|
8
|
Tozaki T, Hirota K, Sugita S, Ishida N, Miyake T, Oki H, Hasegawa T. A genome-wide scan for tying-up syndrome in Japanese Thoroughbreds. Anim Genet 2015; 41 Suppl 2:80-6. [PMID: 21070280 DOI: 10.1111/j.1365-2052.2010.02112.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Tying-up syndrome, also known as recurrent exertional rhabdomyolysis in Thoroughbreds, is a common muscle disorder for racehorses. In this study, we performed a multipoint linkage analysis using LOKI based on the Bayesian Markov chain Monte Carlo method using 5 half-sib families (51 affected and 277 nonaffected horses in total), and a genome-wide association study (GWAS) using microsatellites (144 affected and 144 nonaffected horses) to map candidate regions for tying-up syndrome in Japanese Thoroughbreds. The linkage analysis identified one strong L-score (82.45) between the loci UCDEQ411 and COR058 (24.9-27.9 Mb) on ECA12. The GWAS identified two suggestive genomic regions on ECA12 (24.9-27.8 Mb) and ECA20 (29.3-33.5 Mb). Based on both results, the genomic region between UCDEQ411 and TKY499 (24.9-27.8 Mb) on ECA12 was the most significant and was considered as a candidate region for tying-up syndrome in Japanese Thoroughbreds.
Collapse
Affiliation(s)
- T Tozaki
- Department of Molecular Genetics, Laboratory of Racing Chemistry, Utsunomiya, Tochigi, Japan.
| | | | | | | | | | | | | |
Collapse
|
9
|
Graham S, Freeman D. Standing diagnostic and therapeutic equine abdominal surgery. Vet Clin North Am Equine Pract 2014; 30:143-68. [PMID: 24680210 DOI: 10.1016/j.cveq.2013.11.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The widespread use of laparoscopy in equine surgery has increased interest in the standing approach to a wide range of procedures typically regarded as feasible only through a ventral midline incision. Although a commonly cited benefit of standing surgery relates to avoiding costs of general anesthesia and risks associated with it, some procedures and horses are not suitable candidates for standing abdominal procedures. Some procedures, such as nephrectomy, colostomy, and closure of the nephrosplenic space, are not only suitable for standing surgery but are performed more easily and more safely through this approach than with general anesthesia.
Collapse
Affiliation(s)
- Sarah Graham
- Large Animal Clinical Sciences, University of Florida, Gainesville, FL, USA.
| | - David Freeman
- Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| |
Collapse
|
10
|
Frederick J, Freeman DE, MacKay RJ, Matyjaszek S, Lewis J, Sanchez LC, Meyer S. Removal of ureteral calculi in two geldings via a standing flank approach. J Am Vet Med Assoc 2012; 241:1214-20. [DOI: 10.2460/javma.241.9.1214] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
11
|
Toribio RE. Disorders of Calcium and Phosphate Metabolism in Horses. Vet Clin North Am Equine Pract 2011; 27:129-47. [DOI: 10.1016/j.cveq.2010.12.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
12
|
Aleman M. A review of equine muscle disorders. Neuromuscul Disord 2008; 18:277-87. [DOI: 10.1016/j.nmd.2008.01.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2007] [Revised: 12/17/2007] [Accepted: 01/06/2008] [Indexed: 10/22/2022]
|
13
|
|
14
|
|
15
|
Stewart AJ, Hardy J, Kohn CW, Toribio RE, Hinchcliff KW, Silver B. Validation of diagnostic tests for determination of magnesium status in horses with reduced magnesium intake. Am J Vet Res 2004; 65:422-30. [PMID: 15077683 DOI: 10.2460/ajvr.2004.65.422] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the diagnostic value of serum concentrations of total magnesium (tMg) and ionized magnesium (iMg), concentrations of magnesium (Mg) in muscle, intracellular Mg (icMg) concentrations, urinary Mg excretion (EMg), Mg clearance (CMg), and fractional clearance of Mg (FCMg) in horses fed diets with Mg content above and below National Research Council recommendations. ANIMALS 9 young female horses. PROCEDURES 6 horses were fed a reduced-Mg diet for 29 days followed by an Mg-supplemented diet for 24 days. Control horses (n = 3) were fed grass hay exclusively. Blood, urine, and tissue samples were collected, and an Mg retention test was performed before and after restriction and supplementation of Mg intake. Serum tMg, serum iMg, muscle Mg, icMg, and urine Mg concentrations were measured, and 24-hour EMg, CMg, and FCMg were calculated. RESULTS Reductions in urinary 24-hour EMg, CMg, and FCMg were evident after 13 days of feeding a reduced-Mg diet. Serum tMg and iMg concentrations, muscle Mg content, and results of the Mg retention test were not affected by feeding the Mg-deficient diet. Spot urine sample FCMg accurately reflected FCMg calculated from 6- and 24-hour pooled urine samples. Mean +/- SD FCtMg of horses eating grass hay was 29 +/- 8%, whereas mean FCtMg for horses fed a reduced-Mg diet for 29 days was 6 +/- 3%. CONCLUSIONS AND CLINICAL RELEVANCE The 24-hour EMg was the most sensitive indicator of reduced Mg intake in horses. Spot sample FCMg can be conveniently used to identify horses consuming a diet deficient in Mg.
Collapse
Affiliation(s)
- Allison J Stewart
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA
| | | | | | | | | | | |
Collapse
|
16
|
McKenzie EC, Valberg SJ, Godden SM, Pagan JD, Carlson GP, MacLeay JM, DeLaCorte FD. Comparison of volumetric urine collection versus single-sample urine collection in horses consuming diets varying in cation-anion balance. Am J Vet Res 2003; 64:284-91. [PMID: 12661867 DOI: 10.2460/ajvr.2003.64.284] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine daily variation in urinary clearance and fractional excretion (FE) of electrolytes and minerals within and between horses and to compare volumetric and single-sample urine collection for determining FE values of diets with a range of dietary cation-anion balance (DCAB). ANIMALS 5 Thoroughbred and 6 mixed-breed mares. PROCEDURE 3 isocaloric diets with low, medium, and high DCAB values (85, 190, and 380 mEq/kg of dry matter, respectively) were each fed for 14 days. Daily blood samples, single urine samples collected by using a urinary catheter (5 mares), and volumetric urine collections (6 mares) were obtained during the last 72 hours of each diet. RESULTS Urine and plasma pH values, plasma concentrations, and FE values of sodium, chloride, potassium, magnesium, phosphorus, and calcium were altered by varying the DCAB. Noticeable variation in clearance and FE values was detected within horses from day-to-day on the same diet as well as between horses. Fractional excretion values were not significantly different between single-sample and volumetric methods, except for magnesium in the high DCAB diet. Volumetric and single-sample collections revealed similar patterns of change in urinary FE values with varying DCAB, except for calcium and magnesium. CONCLUSIONS AND CLINICAL RELEVANCE Substantial variation in clearance and FE of electrolytes and minerals are evident within horses between 24-hour periods as well as between horses fed a specific diet. Three daily urine samples provide similar information regarding dietary-induced changes in clearance and FE values (excluding calcium and magnesium) as that obtained by volumetric urine collection.
Collapse
Affiliation(s)
- Erica C McKenzie
- Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA
| | | | | | | | | | | | | |
Collapse
|