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Grob AJ, Delarocque J, Feige K, Warnken T. Evaluating insulindysregulation in horses: A two-step insulin-tolerance test using porcine zinc insulin. Vet J 2024; 306:106172. [PMID: 38909714 DOI: 10.1016/j.tvjl.2024.106172] [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: 12/21/2023] [Revised: 05/22/2024] [Accepted: 06/12/2024] [Indexed: 06/25/2024]
Abstract
In insulin dysregulation, hyperinsulinemia (HI) can be accompanied by peripheral insulin resistance (IR) in horses, which can be diagnosed with an insulin-tolerance test (ITT). The administration of 0.1 IU/kg body weight of recombinant regular human insulin (RHI) should elicit a 50 % reduction of the initial blood glucose concentration at 30 min after insulin administration in insulin sensitive horses. Compared to RHI, porcine zinc insulin (PZI) is veterinary-approved and therefore easier accessible for many practitioners. The aim of this study was to compare the insulin and glucose dynamics during a standard ITT with RHI to an ITT performed with PZI. Twelve Icelandic horses were subjected to an ITT with RHI (ITT-RHI) and with PZI (ITT-PZI) at same dosages in a randomised crossover design. The insulin and glucose dynamics that resulted from these tests were compared, and the consistency of classification into insulin-sensitive and IR categories was evaluated. No complications were observed with the use of either RHI or PZI in ITT. A good correlation of the test results was observed (r = 0.88; P < 0.001). The blood glucose concentrations and the percentage reduction in glucose concentration did not differ significantly between the two tests (P = 0.053), but four out of twelve horses were classified as IR in the ITT-RHI whereas with the ITT-PZI seven out of twelve horses were classified as IR with the 50 % glucose reduction from baseline. Based on the Youden index, when using the ITT-PZI, an adjusted cut-off value for blood glucose reduction of 40 % at 30 min resulted in better test performance. With consideration for the seemingly weaker effect of PZI and the adjusted cut-off value, PZI can be an appropriate substitute to RHI in an ITT.
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Affiliation(s)
- A J Grob
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover 30559, Germany
| | - J Delarocque
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover 30559, Germany
| | - K Feige
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover 30559, Germany
| | - T Warnken
- Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover 30559, Germany
- Boehringer Ingelheim Vetmedica GmbH, Binger Straße 173, Ingelheim am Rhein 55263, Germany
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Clark BL, Bamford NJ, Stewart AJ, McCue ME, Rendahl A, Bailey SR, Bertin FR, Norton EM. Evaluation of an HMGA2 variant contribution to height and basal insulin concentrations in ponies. J Vet Intern Med 2023; 37:1186-1192. [PMID: 37148171 DOI: 10.1111/jvim.16723] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 04/08/2023] [Indexed: 05/08/2023] Open
Abstract
BACKGROUND The HMGA2:c.83G>A variant was identified in Welsh ponies having pleiotropic effects on height and insulin concentration. OBJECTIVE Determine whether the HMGA2:c.83G>A variant is associated with decreased height and higher basal insulin concentrations across pony breeds. ANIMALS Two hundred thirty-six ponies across 6 breeds. METHODS Cross-sectional study. Ponies were genotyped for the HMGA2:c.83G>A variant and phenotyped for height and basal insulin concentrations. Stepwise regression was performed for model analysis using a linear regression model for height and mixed linear model for insulin with farm as a random effect. Coefficient of determination, pairwise comparison of the estimated marginal means and partial correlation coefficients (parcor) were calculated to assess the relationship between HMGA2 genotype and height or insulin. RESULTS Breed and genotype accounted for 90.5% of the variation in height across breeds, and genotype explained 21% to 44% of the variation within breeds. Breed, genotype, cresty neck score, sex, age, and farm accounted for 45.5% of the variation in insulin, with genotype accounting for 7.1%. The HMGA2 A allele frequency was 62% and correlated with both height (parcor = -0.39; P < .001) and insulin (parcor = 0.22; P = .02). Pairwise comparisons found A/A ponies were >10 cm shorter than other genotypes. Compared with G/G individuals, A/A and G/A individuals had 4.3 μIU/mL (95% confidence interval [CI]: 1.8-10.5) and 2.7 μIU/mL (95% CI: 1.4-5.3) higher basal insulin concentrations, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE These data demonstrate the pleiotropic effects of the HMGA2:c.83G>A variant and its role in identifying ponies at increased risk for insulin dysregulation.
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Affiliation(s)
- Brianna L Clark
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia
| | - Nicholas J Bamford
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Allison J Stewart
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia
| | - Molly E McCue
- College of Veterinary Medicine, The University of Minnesota, St Paul, Minnesota, USA
| | - Aaron Rendahl
- College of Veterinary Medicine, The University of Minnesota, St Paul, Minnesota, USA
| | - Simon R Bailey
- Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - François-René Bertin
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia
| | - Elaine M Norton
- College of Agricultural and Life Sciences, The University of Arizona, Tucson, Arizona, USA
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Weinert-Nelson JR, Biddle AS, Sampath H, Williams CA. Fecal Microbiota, Forage Nutrients, and Metabolic Responses of Horses Grazing Warm- and Cool-Season Grass Pastures. Animals (Basel) 2023; 13:ani13050790. [PMID: 36899650 PMCID: PMC10000167 DOI: 10.3390/ani13050790] [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: 01/13/2023] [Revised: 02/14/2023] [Accepted: 02/14/2023] [Indexed: 02/24/2023] Open
Abstract
Integrating warm-season grasses into cool-season equine grazing systems can increase pasture availability during summer months. The objective of this study was to evaluate effects of this management strategy on the fecal microbiome and relationships between fecal microbiota, forage nutrients, and metabolic responses of grazing horses. Fecal samples were collected from 8 mares after grazing cool-season pasture in spring, warm-season pasture in summer, and cool-season pasture in fall as well as after adaptation to standardized hay diets prior to spring grazing and at the end of the grazing season. Random forest classification was able to predict forage type based on microbial composition (accuracy: 0.90 ± 0.09); regression predicted forage crude protein (CP) and non-structural carbohydrate (NSC) concentrations (p < 0.0001). Akkermansia and Clostridium butyricum were enriched in horses grazing warm-season pasture and were positively correlated with CP and negatively with NSC; Clostridum butyricum was negatively correlated with peak plasma glucose concentrations following oral sugar tests (p ≤ 0.05). These results indicate that distinct shifts in the equine fecal microbiota occur in response different forages. Based on relationships identified between the microbiota, forage nutrients, and metabolic responses, further research should focus on the roles of Akkermansia spp. and Clostridium butyricum within the equine hindgut.
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Affiliation(s)
- Jennifer R. Weinert-Nelson
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Amy S. Biddle
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19711, USA
| | - Harini Sampath
- Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
- Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition, and Health, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Carey A. Williams
- Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
- Correspondence:
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Loos CMM, Urschel KL, Vanzant ES, Oberhaus EL, Bohannan AD, Klotz JL, McLeod KR. Effects of Bromocriptine on Glucose and Insulin Dynamics in Normal and Insulin Dysregulated Horses. Front Vet Sci 2022; 9:889888. [PMID: 35711802 PMCID: PMC9194999 DOI: 10.3389/fvets.2022.889888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/09/2022] [Indexed: 12/04/2022] Open
Abstract
The objectives of the study were to study the effects of the synthetic ergot alkaloid (EA), bromocriptine, on glucose and lipid metabolism in insulin dysregulated (ID, n = 7) and non-ID (n = 8) mares. Horses were individually housed and fed timothy grass hay and two daily concentrate meals so that the total diet provided 120% of daily DE requirements for maintenance. All horses were given intramuscular bromocriptine injections (0.1 mg/kg BW) every 3 days for 14 days. Before and after 14 days of treatment horses underwent a combined glucose-insulin tolerance test (CGIT) to assess insulin sensitivity and a feed challenge (1 g starch/kg BW from whole oats) to evaluate postprandial glycemic and insulinemic responses. ID horses had higher basal plasma concentrations of insulin (P = 0.01) and triglycerides (P = 0.02), and lower concentrations of adiponectin (P = 0.05) compared with non-ID horses. The CGIT response curve showed that ID horses had slower glucose clearance rates (P = 0.02) resulting in a longer time in positive phase (P = 0.03) and had higher insulin concentrations at 75 min (P = 0.0002) compared with non-ID horses. Glucose (P = 0.02) and insulin (P = 0.04) responses to the feeding challenge were lower in non-ID compared to ID horses. Regardless of insulin status, bromocriptine administration increased hay intake (P = 0.03) and decreased grain (P < 0.0001) and total DE (P = 0.0002) intake. Bromocriptine treatment decreased plasma prolactin (P = 0.0002) and cholesterol (P = 0.10) and increased (P = 0.02) adiponectin concentrations in all horses. Moreover, in both groups of horses, bromocriptine decreased glucose clearance rates (P = 0.02), increased time in positive phase (P = 0.04) of the CGIT and increased insulin concentrations at 75 min (P = 0.001). The postprandial glycemic (P = 0.01) and insulinemic (P = 0.001) response following the oats meal was lower after bromocriptine treatment in all horses. In conclusion, in contrast to data in humans and rodents, bromocriptine treatment reduced insulin sensitivity in all horses, regardless of their insulin status. These results indicate that the physiological effects of EA might be different in horses compared to other species. Moreover, because bromocriptine shares a high degree of homology with natural EA, further investigation is warranted in horses grazing endophyte-infected grasses.
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Affiliation(s)
- Caroline M M Loos
- Department of Animal and Food Sciences, University of Kentucky, Lexington, KY, United States
| | - Kristine L Urschel
- Department of Animal and Food Sciences, University of Kentucky, Lexington, KY, United States
| | - Eric S Vanzant
- Department of Animal and Food Sciences, University of Kentucky, Lexington, KY, United States
| | - Erin L Oberhaus
- School of Animal Sciences, Louisiana State University, Baton Rouge, LA, United States
| | - Adam D Bohannan
- Department of Animal and Food Sciences, University of Kentucky, Lexington, KY, United States
| | - James L Klotz
- Forage-Animal Production Research Unit, Agricultural Research Service, United States Department of Agriculture, Lexington, KY, United States
| | - Kyle R McLeod
- Department of Animal and Food Sciences, University of Kentucky, Lexington, KY, United States
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Seasonal Insulin Responses to the Oral Sugar Test in Healthy and Insulin Dysregulated Horses. J Equine Vet Sci 2022; 113:103945. [DOI: 10.1016/j.jevs.2022.103945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 03/30/2022] [Accepted: 04/04/2022] [Indexed: 11/22/2022]
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Mendoza FJ, Buzon-Cuevas A, Toribio RE, Perez-Ecija A. Characterisation of the oral glucose and sugar tolerance tests and the enteroinsular axis response in healthy adult donkeys. Equine Vet J 2021; 54:1123-1132. [PMID: 34897779 DOI: 10.1111/evj.13544] [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: 06/23/2021] [Revised: 10/18/2021] [Accepted: 12/09/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Insulin dysregulation (ID) is diagnosed in horses and ponies using oral glucose (OGTT) and oral sugar (OSTT) tolerance tests. The enteroinsular axis plays a major role in postprandial glucose disposal and insulin response in horses, ponies and foals. The insulin and incretin response to oral carbohydrate challenges has not been characterised in donkeys. OBJECTIVES (a) To characterise OGTT and OSTT, and (b) to assess the plasma incretin response to OGTT and OSTT in healthy donkeys. STUDY DESIGN In vivo experiments. METHODS Six healthy adult female Andalusian donkeys were challenged with OGTT (1 g/kg glucose, 20% solution by nasogastric tube) and OSTT (0.45 mL/kg corn syrup orally by syringe) with a 1-week washout. Blood samples were collected for glucose (spectrophotometry), insulin (radioimmunoassay), glucose-dependent insulinotropic polypeptide (GIP, ELISA) and active glucagon-like peptide-1 (aGLP-1, ELISA) determination over 6 hours. Curves were analysed and proxies calculated. RESULTS Glucose and insulin concentrations peaked at 180 minutes in OGTT, but at 300 and 150 minutes in OSTT, respectively. Plasma GIP concentrations increased in the OGTT and OSTT (peaked at 180 and 360 minutes, respectively), but aGLP-1 increased only in OGTT (240 minutes). MAIN LIMITATIONS Single breed, narrow age and sample, diet, season and not having donkeys with evidence of ID to provide clinical validation. CONCLUSIONS Donkeys have a functional enteroinsular axis that is activated by enteral carbohydrates. Donkeys have evident endocrine differences with horses, supporting the validation of the OSTT and OGTT to assess insulin sensitivity in this species to avoid extrapolation from horses.
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Affiliation(s)
- Francisco J Mendoza
- Department of Animal Medicine and Surgery, University of Cordoba, Cordoba, Spain
| | - Antonio Buzon-Cuevas
- Department of Animal Medicine and Surgery, University of Cordoba, Cordoba, Spain
| | - Ramiro E Toribio
- Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, Ohio, USA
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Karikoski NP, Box JR, Mykkänen AK, Kotiranta VV, Raekallio MR. Variation in insulin response to oral sugar test in a cohort of horses throughout the year and evaluation of risk factors for insulin dysregulation. Equine Vet J 2021; 54:905-913. [PMID: 34713928 PMCID: PMC9545906 DOI: 10.1111/evj.13529] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 10/16/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND The oral sugar test (OST) is commonly used to diagnose insulin dysregulation (ID) and equine metabolic syndrome; however, possible seasonal changes in OST results have not been evaluated. OBJECTIVE To determine the possible variation in insulin response to OST throughout the year and risk factors associated with maximum insulin concentration (InsMax) and ID. STUDY DESIGN Prospective, longitudinal cohort study. METHODS The OST was performed on 29 Finnhorses every other month six times. Serum total adiponectin concentration and phenotypic variables related to obesity were also measured. Changes in InsMax, adiponectin, scale weight, body condition score, cresty neck score (CNS), and fasting glucose concentration were assessed. Risk factor analyses were performed on InsMax and ID status, and ID groups were compared with each other. RESULTS Fourteen horses were categorised with non-ID each time and 15 as having ID at least once during the follow-up period. The ID status of 12 horses varied throughout the year, but neither the insulin variables measured during the OST nor adiponectin expressed significant seasonal variation. Increasing age and CNS, and decreasing adiponectin were observed as risk factors for a high InsMax after OST. The risk of ID was higher in horses with no exercise compared to horses with exercise (OR 7.6, 95% CI 1.2-49.3, P = .03). Horses with ID had lower serum adiponectin concentrations, longer neck circumference and larger height than horses in the non-ID group. MAIN LIMITATIONS The environmental conditions (feeding, exercise) were not constant for all horses throughout the study and only one breed was used. CONCLUSIONS Neither OST results nor adiponectin varies with season; however, there were a substantial number of horses with variable ID status throughout the year, in which repeated OSTs may be beneficial. Lack of exercise was a risk factor for ID.
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Affiliation(s)
- Ninja P Karikoski
- Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Justin R Box
- Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Anna K Mykkänen
- Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Veikko V Kotiranta
- Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Marja R Raekallio
- Department of Equine and Small Animal Sciences, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
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8
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Mendoza FJ, Mejia-Moreira S, Buchanan BR, Toribio RE, Perez-Ecija A. Evaluation of the combined glucose-insulin and intravenous glucose tolerance tests for insulin dysregulation diagnosis in donkeys. Equine Vet J 2021; 54:531-540. [PMID: 34109681 DOI: 10.1111/evj.13482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 05/13/2021] [Accepted: 05/29/2021] [Indexed: 01/08/2023]
Abstract
BACKGROUND Insulin dysregulation (ID) and donkey metabolic syndrome (DMS) are common in this species. Contrary to horses, diagnostic guidelines compiling insulin cut-offs values and dynamic testing interpretations have not been reported for this species. OBJECTIVES To evaluate resting serum insulin concentrations, the combined glucose-insulin test (CGIT) and the glucose intravenous tolerance test (IVGTT) for the diagnosis of DMS with ID suspicion. STUDY DESIGN Diagnostic test comparison. METHODS Six of 80 mix-breed adult donkeys fulfilled the inclusion criteria for DMS based on history or clinical evidence of recurrent laminitis, body condition >6 and neck score >2 or baseline insulin and leptin concentrations >20 µIU/mL and >12 ng/mL respectively. CGIT and IVGTT were performed in all donkeys within a week and interpreted following guidelines reported for equine metabolic syndrome (EMS). Insulin and glucose curves were analysed, proxies calculated and correlations and multivariate analysis assessed. RESULTS Following EMS guidelines, CGIT classified 2 (using glucose-positive phase duration) or 3 (using insulin concentration) and IVGTT classified 5 donkeys as ID. ID donkeys showed a lower glucose/insulin ratio, QUICKI and RISQI, and a higher insulin/glucose ratio, MIRG and HOMA-B%. MAIN LIMITATIONS Comparison of these tests with additional dynamic testing including a larger number of ID donkeys is necessary. CONCLUSIONS This is the first study evaluating dynamic tests to assess ID/DMS in DMS-suspected donkeys. IVGTT detected more ID donkeys than CGIT. EMS recommendations could also be used for DMS diagnosis, although a baseline insulin cut-off value is needed.
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Affiliation(s)
| | | | | | - Ramiro E Toribio
- Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, OH, USA
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Genome-Wide Association Analyses of Equine Metabolic Syndrome Phenotypes in Welsh Ponies and Morgan Horses. Genes (Basel) 2019; 10:genes10110893. [PMID: 31698676 PMCID: PMC6895807 DOI: 10.3390/genes10110893] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 10/31/2019] [Accepted: 11/01/2019] [Indexed: 12/23/2022] Open
Abstract
Equine metabolic syndrome (EMS) is a complex trait for which few genetic studies have been published. Our study objectives were to perform within breed genome-wide association analyses (GWA) to identify associated loci in two high-risk breeds, coupled with meta-analysis to identify shared and unique loci between breeds. GWA for 12 EMS traits identified 303 and 142 associated genomic regions in 264 Welsh ponies and 286 Morgan horses, respectively. Meta-analysis demonstrated that 65 GWA regions were shared across breeds. Region boundaries were defined based on a fixed-size or the breakdown of linkage disequilibrium, and prioritized if they were: shared between breeds or across traits (high priority), identified in a single GWA cohort (medium priority), or shared across traits with no SNPs reaching genome-wide significance (low priority), resulting in 56 high, 26 medium, and seven low priority regions including 1853 candidate genes in the Welsh ponies; and 39 high, eight medium, and nine low priority regions including 1167 candidate genes in the Morgans. The prioritized regions contained protein-coding genes which were functionally enriched for pathways associated with inflammation, glucose metabolism, or lipid metabolism. These data demonstrate that EMS is a polygenic trait with breed-specific risk alleles as well as those shared across breeds.
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10
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Elzinga SE, Betancourt A, Stewart JC, Altman MH, Barker VD, Muholland M, Bailey S, Brennan KM, Adams AA. Effects of Docosahexaenoic Acid-Rich Microalgae Supplementation on Metabolic and Inflammatory Parameters in Horses With Equine Metabolic Syndrome. J Equine Vet Sci 2019; 83:102811. [PMID: 31791524 DOI: 10.1016/j.jevs.2019.102811] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 10/14/2019] [Accepted: 10/14/2019] [Indexed: 12/11/2022]
Abstract
Much of the equine population is obese and therefore predisposed to the development of additional health concerns such as equine metabolic syndrome (EMS). However, pharmacologic treatments for EMS are limited. Omega-3 fatty acid supplementation is a therapeutic strategy in humans with metabolic dysfunction that improves insulin sensitivity and reduces inflammation, but the effects of omega-3 fatty acid supplementation in horses with EMS are unclear. Therefore, in this pilot study, 10 mixed-sex and mixed-breed horses with EMS were fed a docosahexaenoic acid (DHA)-rich microalgae containing 16 g DHA/horse/d or served as controls for 46 days. Inflammatory status was measured using serologic enzyme-linked immunosorbent assay and in peripheral blood mononuclear cells (PBMCs) using flow cytometry and reverse transcription polymerase chain reaction. Circulating fatty acids, triglyceride, leptin, and adiponectin concentrations were also determined. Insulin and glucose dynamics were assessed with oral sugar test (OST) and frequently sampled intravenous glucose tolerance testing. Postsupplementation, treated horses had an increase in many circulating fatty acids, including DHA (P < .001). Treated horses also had lower serum triglycerides postsupplementation (P = .02) and a trend (P = .07) for reduced PBMC tumor necrosis factor α. Interestingly, after 46 days, control horses had an increase in insulin responses to the OST (P = .01), whereas treated horses did not (P = .69). These pilot data indicate that DHA-rich microalgae supplementation alters circulating fatty acids, modulates metabolic parameters, and may reduce inflammation in horses with EMS.
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Affiliation(s)
- Sarah E Elzinga
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY.
| | - Alejandra Betancourt
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY
| | - John C Stewart
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY
| | - Melissa H Altman
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY
| | - Virginia D Barker
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY
| | - Mason Muholland
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY
| | - Simon Bailey
- Faculty of Veterinary and Agricultural Sciences, Melbourne Veterinary School, University of Melbourne, Werribee, Victoria, Australia
| | | | - Amanda A Adams
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY
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Mendoza FJ, Toribio RE, Perez-Ecija A. Metabolic and Endocrine Disorders in Donkeys. Vet Clin North Am Equine Pract 2019; 35:399-417. [PMID: 31587976 DOI: 10.1016/j.cveq.2019.07.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The donkey evolved under harsh and arid environmental conditions, developing unique energy-efficiency traits, with an efficiency to rapidly mobilize fat in situations of increased energy demands or when food is scarce. This evolution has led to an inherent predisposition of donkeys to obesity, dyslipidemias, insulin dysregulation/metabolic syndrome, pituitary pars intermedia dysfunction, and endocrinopathic laminitis. Marked differences have been described in hormone dynamics and testing protocols for the diagnosis of these endocrine and metabolic diseases in donkeys compared with horses, underlining the necessity of a species-specific approach in order to avoid misdiagnosis, unnecessary or inadequate treatments, and additional costs.
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Affiliation(s)
- Francisco J Mendoza
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Road Madrid-Cadiz km 396, Cordoba 14014, Spain.
| | - Ramiro E Toribio
- Department of Veterinary Clinical Sciences, The Ohio State University, 601 Vernon Tharp Street, Columbus, OH 43210, USA
| | - Alejandro Perez-Ecija
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Road Madrid-Cadiz km 396, Cordoba 14014, Spain
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12
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Hodge E, Kowalski A, Torcivia C, Lindborg S, Stefanovski D, Hart K, Frank N, van Eps A. Effect of thyrotropin-releasing hormone stimulation testing on the oral sugar test in horses when performed as a combined protocol. J Vet Intern Med 2019; 33:2272-2279. [PMID: 31432575 PMCID: PMC6766522 DOI: 10.1111/jvim.15601] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 08/08/2019] [Indexed: 12/31/2022] Open
Abstract
Background The use of parallel dynamic tests to identify insulin dysregulation (ID) and pituitary pars intermedia dysfunction (PPID) in horses could have better diagnostic utility than measuring baseline hormone concentrations, if the tests do not alter diagnostic interpretation of one another. Hypothesis Performing a thyrotropin‐releasing hormone (TRH) stimulation test before an oral sugar test (OST) would not affect results of OST. Animals Twenty‐six healthy university‐owned horses. Methods A prospective randomized placebo‐controlled, crossover design was used to evaluate 3 OST protocols: OST alone, TRH followed by OST (TRH + OST), and placebo followed by OST (placebo + OST). Agreement for plasma insulin concentrations and diagnostic interpretation were assessed with Bland‐Altman and logistic regression analyses, respectively. Results Bland‐Altman analysis of TRH + OST versus OST alone showed good agreement between testing protocols, with bias ± SD for insulin concentrations at baseline 0.4 ± 4.7 μIU/mL (95% limits of agreement [LOA], −8.8 to 9.7), 60 minute −0.5 ± 22.6 μIU/mL (95% LOA, −44.7 to 43.8), and 90 minute 1.9 ± 20.6 μIU/mL (95% LOA, −38.5 to 42.4) after OST, similar to placebo + OST versus OST alone. Diagnostic interpretation (positive/negative) was not different between protocols (TRH + OST versus OST alone [P = .78], placebo + OST versus OST alone [P = .77], or TRH + OST versus placebo + OST [P = .57]). Conclusions and Clinical Importance Concurrent testing for PPID and ID with a TRH stimulation test before an OST is an acceptable diagnostic tool for investigation of endocrinopathies in horses and allows accurate testing to be performed efficiently in 1 visit.
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Affiliation(s)
- Elizabeth Hodge
- School of Veterinary Medicine, University of Pennsylvania, Clinical Studies-New Bolton Center, Kennett Square, Chester, Pennsylvania
| | - Alycia Kowalski
- School of Veterinary Medicine, University of Pennsylvania, Clinical Studies-New Bolton Center, Kennett Square, Chester, Pennsylvania
| | - Catherine Torcivia
- School of Veterinary Medicine, University of Pennsylvania, Clinical Studies-New Bolton Center, Kennett Square, Chester, Pennsylvania
| | - Sue Lindborg
- School of Veterinary Medicine, University of Pennsylvania, Clinical Studies-New Bolton Center, Kennett Square, Chester, Pennsylvania
| | - Darko Stefanovski
- School of Veterinary Medicine, University of Pennsylvania, Clinical Studies-New Bolton Center, Kennett Square, Chester, Pennsylvania
| | - Kelsey Hart
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, Georgia
| | - Nicholas Frank
- Department of Clinical Sciences, Tufts Cummings School of Veterinary Medicine, North Grafton, Massachusetts
| | - Andrew van Eps
- School of Veterinary Medicine, University of Pennsylvania, Clinical Studies-New Bolton Center, Kennett Square, Chester, Pennsylvania
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Effects of Sting Plant Extracts as Penetration Enhancers on Transdermal Delivery of Hypoglycemic Compounds. ACTA ACUST UNITED AC 2019; 55:medicina55050121. [PMID: 31067805 PMCID: PMC6572286 DOI: 10.3390/medicina55050121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/17/2019] [Accepted: 04/17/2019] [Indexed: 11/17/2022]
Abstract
Background and objectives: The percutaneous route is an interesting and inventive investigation field of drug delivery. However, it is challenging for drug molecules to pass through the skins surface, which is a characterized by its permeability barrier. The purpose of this study is to look at the effect of some penetration enhancers on in vivo permeation of insulin and insulin sensitizers (curcumin and rutin) through diabetes-induced mouse skin. Materials and Methods: Sting crude extracts of Dendrocnide meyeniana, Urtica thunbergiana Sieb. and Zucc, and Alocasia odora (Lodd.) Spach were used as the penetration enhancers. Mouse skin irritation was tested by smearing the enhancers for the measurements at different time points and the cell viability of the HaCaT human skin keratinocytes, which was determined by Trypan blue exclusion and MTT assays to evaluate human biosafety for these extracts after the mouse skin permeation experiments. Results: All enhancers induced a slight erythema without edema on the mouse skin that completely recovered after 6 h from the enhancer smears as compared with normal mouse skin. Furthermore, no damaged cells were found in the HaCaT keratinocytes under sting crude extract treatments. The blood sugar level in the diabetic mice treated with the insulin or insulin sensitizers, decreased significantly (p < 0.05) in the presence of enhancers. The area under the curve (AUC) values of transdermal drug delivery (TDD) ranged from 42,000 ± 5000 mg/dL x min without enhancers, to 30,000 ± 2000 mg/dL x min in the presence of enhancers. Conclusions: This study exhibited that natural plant extracts could be preferred over the chemically synthesized molecules and are safe and potent penetration enhancers for stimulating the transdermal absorption of drugs.
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14
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Norton EM, Schultz NE, Rendahl AK, Mcfarlane D, Geor RJ, Mickelson JR, McCue ME. Heritability of metabolic traits associated with equine metabolic syndrome in Welsh ponies and Morgan horses. Equine Vet J 2018; 51:475-480. [DOI: 10.1111/evj.13053] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 11/19/2018] [Indexed: 12/29/2022]
Affiliation(s)
- E. M. Norton
- Veterinary Population Medicine Department 225 Veterinary Medical Center University of Minnesota St. Paul Minnesota USA
| | - N. E. Schultz
- Veterinary Population Medicine Department 225 Veterinary Medical Center University of Minnesota St. Paul Minnesota USA
| | - A. K. Rendahl
- Veterinary and Biomedical Sciences Department University of Minnesota St. Paul Minnesota USA
| | - D. Mcfarlane
- Department of Physiological Sciences Oklahoma State University Stillwater Oklahoma USA
| | - R. J. Geor
- College of Sciences Massey University Palmerston North New Zealand
| | - J. R. Mickelson
- Veterinary and Biomedical Sciences Department University of Minnesota St. Paul Minnesota USA
| | - M. E. McCue
- Veterinary Population Medicine Department 225 Veterinary Medical Center University of Minnesota St. Paul Minnesota USA
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15
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Morrison PK, Newbold CJ, Jones E, Worgan HJ, Grove-White DH, Dugdale AH, Barfoot C, Harris PA, Argo CM. The Equine Gastrointestinal Microbiome: Impacts of Age and Obesity. Front Microbiol 2018; 9:3017. [PMID: 30581426 PMCID: PMC6293011 DOI: 10.3389/fmicb.2018.03017] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 11/22/2018] [Indexed: 12/11/2022] Open
Abstract
Gastrointestinal microbial communities are increasingly being implicated in host susceptibilities to nutritional/metabolic diseases; such conditions are more prevalent in obese and/or older horses. This controlled study evaluated associations between host-phenotype and the fecal microbiome / metabolome. Thirty-five, Welsh Mountain pony mares were studied across 2 years (Controls, n = 6/year, 5–15 years, Body Condition Score (BCS) 4.5–6/9; Obese, n = 6/year, 5–15 years, BCS > 7/9; Aged, n = 6 Year 1; n = 5 Year 2, ≥19 years old). Animals were individually fed the same hay to maintenance (2% body mass as daily dry matter intake) for 2 (aged / obese) or 4 (control), 4-week periods in a randomized study. Outset phenotype was determined (body fat%, markers of insulin sensitivity). Feces were sampled on the final 3 days of hay feeding-periods and communities determined using Next Generation Sequencing of amplified V1–V2 hypervariable regions of bacterial 16S rRNA. Copy numbers for fecal bacteria, protozoa and fungi were similar across groups, whilst bacterial diversity was increased in the obese group. Dominant bacterial phyla in all groups were Bacteroidetes > Firmicutes > Fibrobacter. Significant differences in the bacterial communities of feces were detected between host-phenotype groups. Relative to controls, abundances of Proteobacteria were increased for aged animals and Bacteroidetes, Firmicutes, and Actinobacteria were increased for obese animals. Over 500 bacterial operational taxonomic units (OTUs) differed significantly between host-phenotype groups. No consistent pattern of changes in discriminant OTUs between groups were maintained across groups and between years. The core bacterial populations contained 21 OTUs, 6.7% of recovered sequences. Distance-based Redundancy Analyses separated fecal bacterial communities with respect to markers of obesity and insulin dysregulation, as opposed to age. Host-phenotype had no impact on the apparent digestibility of dietary GE or DM, fecal volatile fatty acid concentrations or the fecal metabolome (FT-IR). The current study demonstrates that host-phenotype has major effects on equine fecal microbial population structure. Changes were predominantly associated with the obese state, confirming an obesity-associated impact in the absence of nutritional differences. Clear biomarkers of animal-phenotype were not identified within either the fecal microbiome or metabolome, suggesting functional redundancy within the gut microbiome and/or metabolome.
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Affiliation(s)
| | | | - Eleanor Jones
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, United Kingdom
| | - Hilary J Worgan
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, United Kingdom
| | - Dai H Grove-White
- Faculty of Health and Life Sciences, University of Liverpool, Wirral, United Kingdom
| | | | - Clare Barfoot
- MARS Horsecare UK Ltd., Buckinghamshire, United Kingdom
| | - Patricia A Harris
- Equine Studies Group, WALTHAM Centre for Pet Nutrition, Leicestershire, United Kingdom
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16
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Effect of intravenous glucose and combined glucose-insulin challenges on energy-regulating hormones concentrations in donkeys. Vet J 2018; 240:40-46. [DOI: 10.1016/j.tvjl.2018.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 08/21/2018] [Accepted: 09/02/2018] [Indexed: 01/02/2023]
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17
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Mendoza FJ, Toribio RE, Perez-Ecija A. Donkey Internal Medicine—Part I: Metabolic, Endocrine, and Alimentary Tract Disturbances. J Equine Vet Sci 2018. [PMCID: PMC7111315 DOI: 10.1016/j.jevs.2018.02.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Metabolic and endocrine disturbances are common in donkeys. This species has an inherent ability to thrive with limited and poor-quality roughage. Donkeys are extremely efficient in energy storage and mobilization, which predisposes to hyperlipemia, obesity, and metabolic syndrome. The prevalence of dyslipidemias is higher in donkeys than other equids, which is more evident under stressful conditions. Diagnosis of endocrine and metabolic disorders in donkeys should be based on species-specific information considering that differences in a multitude of variables compared with horses have been demonstrated. Protocols to assess endocrine disorders (e.g., pituitary pars intermedia dysfunction, metabolic syndrome, and thyroid illness) are unavailable, and extrapolation from horse data can be misleading. Treatment guidelines for these conditions in donkeys are currently not reported. On the other hand, the typical stoic and hardy behavior of donkeys can hinder prompt diagnosis of gastrointestinal problems, specifically colic, which is commonly caused by dental issues in this species. Moreover, subclinical gastric ulcer syndrome appears to be a common pathology in this species, especially in working donkeys. Donkeys are different to horses. Numerous physiological and clinic-pathologic idiosyncrasies are reported in horses. Data published for horses should not be extrapolated for donkeys. Specific reference ranges, doses, and protocols have to be used for donkeys.
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Affiliation(s)
- Francisco J. Mendoza
- Departamento de Medicina y Cirugia Animal, Universidad de Cordoba, Campus Rabanales, Cordoba, Spain
- Corresponding author at: Dr Francisco J. Mendoza, Department of Animal Medicine and Surgery University of Cordoba, 14014 Cordoba, Spain.
| | - Ramiro E. Toribio
- Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, OH
| | - Alejandro Perez-Ecija
- Departamento de Medicina y Cirugia Animal, Universidad de Cordoba, Campus Rabanales, Cordoba, Spain
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18
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Lindåse SS, Nostell KE, Müller CE, Jensen-Waern M, Bröjer JT. Effects of diet-induced weight gain and turnout to pasture on insulin sensitivity in moderately insulin resistant horses. Am J Vet Res 2016; 77:300-9. [PMID: 26919602 DOI: 10.2460/ajvr.77.3.300] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To quantify insulin sensitivity and monitor glucose, insulin, and lipid concentrations in a group of moderately insulin-resistant horses during induction of obesity by use of a forage diet supplemented with fat and during subsequent turnout to pasture. ANIMALS 9 adult Standardbred mares (11 to 20 years old). PROCEDURES Weight gain of horses was induced during 22 weeks by use of a forage diet supplemented with fat fed in gradually increasing amounts, followed by feeding of that fat-supplemented diet at 2.5 times the daily maintenance requirements. Horses were then turned out to pasture. Insulin sensitivity was measured with the euglycemic hyperinsulinemic clamp method before and after weight gain and after 4 weeks at pasture. Body weight, body condition score, and cresty neck score as well as fasting and postprandial concentrations of plasma insulin, plasma glucose, serum triglyceride, and serum nonesterified fatty acids were measured during the study. RESULTS Body weight typically increased by 10%, and body condition score (scale, 1 to 9) increased by > 1.5 from the start to the end of the weight-gain period. There was no difference in insulin sensitivity or metabolic clearance rate of insulin during the weight-gain period. Four weeks at pasture generally improved insulin sensitivity and metabolic clearance rate of insulin by 54% and 32%, respectively, but there was no change in body weight or body condition score. CONCLUSIONS AND CLINICAL RELEVANCE Findings indicated that dietary composition played a more important role than did short-term weight gain on alterations in insulin sensitivity of horses.
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Mendoza FJ, Aguilera-Aguilera R, Gonzalez-De Cara CA, Toribio RE, Estepa JC, Perez-Ecija A. Characterization of the intravenous glucose tolerance test and the combined glucose-insulin test in donkeys. Vet J 2015; 206:371-6. [PMID: 26515163 DOI: 10.1016/j.tvjl.2015.08.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 08/08/2015] [Accepted: 08/10/2015] [Indexed: 11/15/2022]
Abstract
Glucose-insulin dynamic challenges such as the intravenous glucose tolerance test (IVGTT) and combined glucose-insulin test (CGIT) have not been described in donkeys. The objectives of this study were (1) to characterize the IVGTT and CGIT in healthy adult donkeys, and (2) to establish normal glucose-insulin proxies. Sixteen donkeys were used and body morphometric variables obtained each. For the IVGTT, glucose (300 mg/kg) was given IV. For the CGIT, glucose (150 mg/kg) followed by recombinant insulin (0.1 IU/kg) were administered IV. Blood samples for glucose and insulin determinations were collected over 300 min. In the IVGTT the positive phase lasted 160.9 ± 13.3 min, glucose concentration peaked at 323.1 ± 9.2 mg/dL and declined at a rate of 1.28 ± 0.15 mg/dL/min. The glucose area under the curve (AUC) was 21.4 ± 1.9 × 10(3) mg/dL/min and the insulin AUC was 7.2 ± 0.9 × 10(3) µIU/mL/min. The positive phase of the CGIT curve lasted 44 ± 3 min, with a glucose clearance rate of 2.01 ± 0.18 mg/dL/min. The negative phase lasted 255.9 ± 3 min, decreasing glucose concentration at rate of -0.63 ± 0.06 mg/dL/min, and reaching a nadir (33.1 ± 3.6 mg/dL) at 118.3 ± 6.3 min. The glucose and insulin AUC values were 15.2 ± 0.9 × 10(3) mg/dL/min and 13.2 ± 0.9 × 10(3) µIU/mL/min. This is the first study characterizing CGIT and IVGTT, and glucose-insulin proxies in healthy adult donkeys. Distinct glucose dynamics, when compared with horses, support the use of species-specific protocols to assess endocrine function.
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Affiliation(s)
- F J Mendoza
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Ctra. Madrid-Cadiz km 396, 14104 Cordoba, Spain.
| | - R Aguilera-Aguilera
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Ctra. Madrid-Cadiz km 396, 14104 Cordoba, Spain
| | - C A Gonzalez-De Cara
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Ctra. Madrid-Cadiz km 396, 14104 Cordoba, Spain
| | - R E Toribio
- Department of Veterinary Clinical Sciences, The Ohio State University, 601 Vernon Tharp Street, Columbus, OH 43210, USA
| | - J C Estepa
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Ctra. Madrid-Cadiz km 396, 14104 Cordoba, Spain
| | - A Perez-Ecija
- Department of Animal Medicine and Surgery, University of Cordoba, Campus Rabanales, Ctra. Madrid-Cadiz km 396, 14104 Cordoba, Spain
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Bertin FR, Pader KS, Lescun TB, Sojka-Kritchevsky JE. Short-term effect of ovariectomy on measures of insulin sensitivity and response to dexamethasone administration in horses. Am J Vet Res 2014; 74:1506-13. [PMID: 24274888 DOI: 10.2460/ajvr.74.12.1506] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the effect of ovariectomy on insulin sensitivity in horses and determine whether the effects of suppression of the hypothalamo-pituitary-adrenal axis differ before and after ovariectomy. ANIMALS 6 healthy mares. PROCEDURES The horses underwent an IV glucose tolerance test (IVGTT), an insulin sensitivity test, and a dexamethasone suppression test before and 5 weeks after ovariectomy. Body weight, serum cortisol and plasma ACTH concentrations, serum insulin-to-blood glucose concentration ratios, and changes in blood glucose concentration with time after injection of glucose or insulin were compared before and after ovariectomy. RESULTS The dexamethasone injection resulted in a decrease in serum cortisol concentration before and after ovariectomy. In all horses, baseline plasma ACTH concentrations were within the reference range before and after ovariectomy. For each mare, results of an IVGTT before and after ovariectomy were considered normal. No significant differences in basal blood glucose concentration or time to reach baseline glucose concentration after an IVGTT were observed. Basal serum insulin concentration and serum insulin-to-blood glucose concentration ratios were not significantly different before or after ovariectomy, nor was the mean time to attain a 50% decrease in blood glucose concentration after insulin injection. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that ovariectomy does not appear to modify dexamethasone response in horses and that it does not modify short-term measures of insulin sensitivity. Findings suggested that horses undergoing ovariectomy are not at higher risk of developing equine metabolic syndrome or hypothalamo-pituitary-adrenal axis dysfunction and associated morbidity.
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Affiliation(s)
- François R Bertin
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907
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Bröjer J, Lindåse S, Hedenskog J, Alvarsson K, Nostell K. Repeatability of the Combined Glucose-Insulin Tolerance Test and the Effect of a Stressor before Testing in Horses of 2 Breeds. J Vet Intern Med 2013; 27:1543-50. [DOI: 10.1111/jvim.12172] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/16/2013] [Accepted: 07/18/2013] [Indexed: 11/28/2022] Open
Affiliation(s)
- J. Bröjer
- Department of Clinical Sciences; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - S. Lindåse
- Department of Clinical Sciences; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - J. Hedenskog
- Department of Clinical Sciences; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - K. Alvarsson
- Department of Clinical Sciences; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - K. Nostell
- Department of Clinical Sciences; Swedish University of Agricultural Sciences; Uppsala Sweden
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Hess TM, Rexford J, Hansen DK, Ahrens NS, Harris M, Engle T, Ross T, Allen KG. Effects of Ω-3 (n-3) Fatty Acid Supplementation on Insulin Sensitivity in Horses. J Equine Vet Sci 2013. [DOI: 10.1016/j.jevs.2012.07.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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