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Elder E, Wong D, Johnson K, Robertson H, Marner M, Dembek K. Assessment of the hypothalamic-pituitary-adrenocortical axis function using a vasopressin stimulation test in neonatal foals. J Vet Intern Med 2023; 37:1881-1888. [PMID: 37432047 PMCID: PMC10473012 DOI: 10.1111/jvim.16808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 06/27/2023] [Indexed: 07/12/2023] Open
Abstract
BACKGROUND Bacterial sepsis is the leading cause of death in foals and is associated with hypothalamic-pituitary-adrenocortical axis (HPAA) dysfunction. HPAA function can be evaluated by an arginine-vasopressin (AVP) stimulation test. HYPOTHESES/OBJECTIVES Administration of AVP will stimulate a dose-dependent rise in systemic adrenocorticotropin-releasing hormone (ACTH) and cortisol in neonatal foals. There will be no response seen in corticotropin-releasing hormone (CRH) and baseline AVP will be within reference interval. ANIMALS Twelve neonatal foals, <72 hours old. METHODS HPAA function was assessed in foals utilizing 3 doses of AVP (2.5, 5, and 7.5 IU), administered between 24 and 48 hours of age in this randomized cross-over study. Cortisol, ACTH, CRH and AVP were measured at 0 (baseline), 15, 30, 60 and 90 minutes after AVP administration with immunoassays. The fold increase in cortisol and ACTH was calculated at 15 and 30 minutes compared to baseline. RESULTS All doses of AVP resulted in a significant increase in cortisol concentration over time, and a dose-dependent increase in ACTH concentration over time. ACTH and cortisol were significantly increased at 15 and 30 minutes, respectively after all 3 doses of AVP compared to baseline (P < .01). There was no change in endogenous CRH after stimulation with AVP. CONCLUSION AND CLINICAL IMPORTANCE Administration of AVP is safe and results in a significant rise in ACTH and cortisol in neonatal foals. A stimulation test with AVP (5 IU) can be considered for HPAA assessment in septic foals.
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Affiliation(s)
- Erin Elder
- Department of Clinical Sciences, College of Veterinary MedicineNorth Carolina State UniversityRaleighNorth CarolinaUSA
| | - David Wong
- Department of Clinical Sciences, College of Veterinary MedicineIowa State UniversityAmesIowaUSA
| | - Katheryn Johnson
- Department of Clinical Sciences, College of Veterinary MedicineIowa State UniversityAmesIowaUSA
| | - Hannah Robertson
- Department of Clinical Sciences, College of Veterinary MedicineNorth Carolina State UniversityRaleighNorth CarolinaUSA
| | | | - Katarzyna Dembek
- Department of Clinical Sciences, College of Veterinary MedicineNorth Carolina State UniversityRaleighNorth CarolinaUSA
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Johnson K, Peterson J, Kopper J, Dembek K. The hypothalamic-pituitary-adrenal axis response to ovine corticotropin-releasing-hormone stimulation tests in healthy and hospitalized foals. Vet Med (Auckl) 2023; 37:292-301. [PMID: 36651191 PMCID: PMC9889673 DOI: 10.1111/jvim.16604] [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: 03/22/2022] [Accepted: 11/23/2022] [Indexed: 01/19/2023]
Abstract
BACKGROUND The hypothalamic-pituitary-adrenocortical axis (HPAA) response to sepsis can be impaired in critical illness. Corticotropin-releasing hormone (CRH) stimulation test might assess HPAA function in foals. OBJECTIVE To evaluate plasma cortisol, ACTH, arginine vasopressin (AVP), and endogenous CRH (eCRH) response to different doses of ovine CRH (oCRH). ANIMALS Healthy (n = 14) and hospitalized (n = 15) foals <7 days of age. METHODS In this prospective randomized study, oCRH (0.1, 0.3, and 1 μg/kg) was administered intravenously and blood samples were collected before, 15, 30, 60, and 90 minutes after administration of oCRH to determine plasma hormone concentrations. The hormonal response was evaluated as the difference (Delta; μg/dL or pg/mL) or percent change between baseline hormone concentration and each time point after oCRH stimulation. RESULTS Cortisol concentrations increased from baseline at 15 minutes with 0.1 and 0.3 μg/kg and at 30 and 60 minutes from baseline with 1 μg/kg oCRH (P < .05) in healthy and hospitalized foals. ACTH concentrations increased from baseline at 15 minutes with 0.1 μg/kg and at 30 minutes with 1 μg/kg oCRH (P < .05) in hospitalized foals. Delta cortisol 0 - 30, ACTH 0 - 30, and eCRH 0 - 30 was higher for the 1 μg/kg compared with 0.1 μg/kg oCRH in healthy foals (P < .05). Delta ACTH 0 - 15 and eCRH 0 - 30 was higher for the 1 μg/kg compared with the lower doses of oCRH in hospitalized foals (P < .05). CONCLUSIONS AND CLINICAL IMPORTANCE Cortisol, ACTH, and eCRH concentrations increased in response to administration of all doses of oCRH. One microgram per kilogram of oCRH appears to be optimal for the assessment of HPAA in healthy and hospitalized foals.
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Affiliation(s)
- Katheryn Johnson
- Department of Veterinary Clinical SciencesIowa State University College of Veterinary MedicineAmesIowaUSA
| | - Jackie Peterson
- Department of Veterinary Clinical SciencesIowa State University College of Veterinary MedicineAmesIowaUSA
| | - Jamie Kopper
- Department of Veterinary Clinical SciencesIowa State University College of Veterinary MedicineAmesIowaUSA
| | - Katarzyna Dembek
- Department of Clinical SciencesNorth Carolina State University College of Veterinary MedicineRaleighNorth CarolinaUSA
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Dembek K, Timko K, Moore C, Johnson L, Frazer M, Barr B, Toribio R. Longitudinal assessment of adrenocortical steroid and steroid precursor response to illness in hospitalized foals. Domest Anim Endocrinol 2023; 82:106764. [PMID: 36162341 DOI: 10.1016/j.domaniend.2022.106764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 10/14/2022]
Abstract
Sepsis is a major cause of morbidity and mortality in neonatal foals. Relative adrenal insufficiency (RAI), defined as an inadequate cortisol response to stress, has been associated with sepsis, prematurity, and poor outcome in newborn foals. In addition to cortisol, the adrenal gland synthesizes several biologically important steroids and steroid precursors, including aldosterone, androgens, and progestogens. However, concentration of these hormones during hospitalization and their association with the severity of disease and mortality in critically ill foals have not been completely evaluated. We hypothesized, that in addition to cortisol and aldosterone, concentration of steroid precursors (progestogens and androgens) will be altered in critically ill foals. We also proposed that septic foals will have higher concentrations of steroid precursors than healthy foals, and steroid concentrations will be persistently increased during hospitalization in non-surviving septic and premature foals. Foals <4 days of age were categorized as healthy, septic, sick non-septic, and premature based on physical exam, medical history, and laboratory data. Blood samples were collected on admission (0 h), 24 h, and 72 h after admission. Concentrations of steroids and ACTH were measured by immunoassays. The area under the curve over 72 h (AUC0-72h) of hospitalization was calculated for each hormone. Serum cortisol, aldosterone, progesterone, pregnenolone, dehydroepiandrosterone sulfate (DHEAS), and 17 α-hydroxyprogesterone concentrations were higher in septic and premature foals compared to healthy foals at 0 h and throughout 72 h of hospitalization (P < 0.05). Plasma ACTH concentrations were higher in septic and premature foals on admission compared to healthy controls (P < 0.05). The progesterone (AUC0-72h) cut-off value above which non-survival could be reliably predicted in hospitalized foals was 1,085 ng/mL/h, with 82% sensitivity and 77% specificity. Critically ill neonatal foals had an appropriate response to stress characterized by increased concentrations of cortisol and steroid precursors on admission. A rapid decline in steroid concentration was observed in healthy foals. However, persistently elevated progestogen and androgen concentrations were associated with a lack of improvement in the course of disease and poor outcome.
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Affiliation(s)
- K Dembek
- College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.
| | - K Timko
- College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
| | - C Moore
- Jacksonville Equine Associates, Jacksonville, FL, USA
| | - L Johnson
- Fairfield Equine Associates, Newtown, CT, USA
| | - M Frazer
- Hagyard Equine Medical Institute, Lexington, KY, USA
| | - B Barr
- Rood and Riddle Equine Hospital, Lexington, KY, USA
| | - R Toribio
- College of Veterinary Medicine, The Ohio State University, Columbus, OH, USA
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Kovac M, Vladimirovna Ippolitova T, Pozyabin S, Aliev R, Lobanova V, Drakul N, S. Rutland C. Equine Stress: Neuroendocrine Physiology and Pathophysiology. Vet Med Sci 2022. [DOI: 10.5772/intechopen.105045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
This review presents new aspects to understanding the neuroendocrine regulation of equine stress responses, and their influences on the physiological, pathophysiological, and behavioral processes. Horse management, in essence, is more frequently confirmed by external and internal stress factors, than in other domestic animals. Regardless of the nature of the stimulus, the equine stress response is an effective and highly conservative set of interconnected relationships designed to maintain physiological integrity even in the most challenging circumstances (e.g., orthopedic injuries, abdominal pain, transport, competitions, weaning, surgery, and inflammation). The equine stress response is commonly a complementary homeostatic mechanism that provides protection (not an adaptation) when the body is disturbed or threatened. It activates numerous neural and hormonal networks to optimize metabolic, cardiovascular, musculoskeletal, and immunological functions. This review looks into the various mechanisms involved in stress responses, stress-related diseases, and assessment, prevention or control, and management of these diseases and stress. Stress-related diseases can not only be identified and assessed better, given the latest research and techniques but also prevented or controlled.
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Hernández-Avalos I, Mota-Rojas D, Mendoza-Flores JE, Casas-Alvarado A, Flores-Padilla K, Miranda-Cortes AE, Torres-Bernal F, Gómez-Prado J, Mora-Medina P. Nociceptive pain and anxiety in equines: Physiological and behavioral alterations. Vet World 2021; 14:2984-2995. [PMID: 35017848 PMCID: PMC8743789 DOI: 10.14202/vetworld.2021.2984-2995] [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: 05/24/2021] [Accepted: 09/23/2021] [Indexed: 01/02/2023] Open
Abstract
Pain and anxiety are two of the most important concerns in clinical veterinary medicine because they arise as consequences of multiple factors that can severely affect animal welfare. The aim of the present review was to provide a description and interpretation of the physiological and behavioral alterations associated with pain and anxiety in equines. To this end, we conducted an extensive review of diverse sources on the topic. The article begins by describing the neurophysiological pathway of pain, followed by a discussion of the importance of the limbic system in responses to pain and anxiety, since prolonged exposure to situations that cause stress and pain generates such physiological changes as tachycardia, tachypnea, hypertension, hyperthermia, and heart rate variability (HRV), often accompanied by altered emotional states, deficient rest, and even aggressiveness. In the long term, animals may show deficiencies in their ability to deal with changes in the environment due to alterations in the functioning of their immune, nervous, and endocrinologic systems. In conclusion, pain and anxiety directly impact the homeostasis of organisms, so it is necessary to conduct objective evaluations of both sensations using behavioral scales, like the horse grimace scale, complemented by assessments of blood biomarkers to analyze their correlation with physiological parameters: Heart rate, respiratory rate, HRV, theparasympathetic tone activity index, lactate and glucose levels, and temperature. Additional tools - infrared thermography, for example - can also be used in these efforts to improve the quality of life and welfare of horses.
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Affiliation(s)
- I. Hernández-Avalos
- Department of Biological Sciences, Clinical Pharmacology and Veterinary Anesthesia, Faculty of Higher Studies Cuautitlán FESC, Universidad Nacional Autónoma de México, State of Mexico 54714, Mexico
| | - D. Mota-Rojas
- Neurophysiology of Pain, Behavior and Assessment of Welfare in Domestic Animals, DPAA, Universidad Autónoma Metropolitana, Mexico City 04960, Mexico
| | - J. E. Mendoza-Flores
- Equine Hospital Faculty of Higher Studies Cuautitlán FESC, Universidad Nacional Autónoma de México, State of Mexico 54714, Mexico
| | - A. Casas-Alvarado
- Neurophysiology of Pain, Behavior and Assessment of Welfare in Domestic Animals, DPAA, Universidad Autónoma Metropolitana, Mexico City 04960, Mexico
| | - K. Flores-Padilla
- Neurophysiology of Pain, Behavior and Assessment of Welfare in Domestic Animals, DPAA, Universidad Autónoma Metropolitana, Mexico City 04960, Mexico
| | - A. E. Miranda-Cortes
- Department of Biological Sciences, Clinical Pharmacology and Veterinary Anesthesia, Faculty of Higher Studies Cuautitlán FESC, Universidad Nacional Autónoma de México, State of Mexico 54714, Mexico
| | - F. Torres-Bernal
- Neurophysiology of Pain, Behavior and Assessment of Welfare in Domestic Animals, DPAA, Universidad Autónoma Metropolitana, Mexico City 04960, Mexico
| | - J. Gómez-Prado
- Neurophysiology of Pain, Behavior and Assessment of Welfare in Domestic Animals, DPAA, Universidad Autónoma Metropolitana, Mexico City 04960, Mexico
| | - P. Mora-Medina
- Department of Livestock Sciences, Animal Welfare, FESC, Universidad Nacional Autónoma de México, State of Mexico 54714, Mexico
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Kinsella HM, Hostnik LD, Rings LM, Swink JM, Burns TA, Toribio RE. Glucagon, insulin, adrenocorticotropic hormone, and cortisol in response to carbohydrates and fasting in healthy neonatal foals. J Vet Intern Med 2021; 35:550-559. [PMID: 33415818 PMCID: PMC7848351 DOI: 10.1111/jvim.16024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 12/18/2020] [Accepted: 12/18/2020] [Indexed: 11/29/2022] Open
Abstract
Background The endocrine pancreas and hypothalamic‐pituitary‐adrenal axis (HPAA) are central to energy homeostasis, but information on their dynamics in response to energy challenges in healthy newborn foals is lacking. Objectives To evaluate glucagon, insulin, ACTH, and cortisol response to fasting and carbohydrate administration in healthy foals. Animals Twenty‐two healthy Standardbred foals ≤4 days of age. Methods Foals were assigned to fasted (n = 6), IV glucose (IVGT; n = 5), PO glucose (OGT; n = 5), and PO lactose (OLT; n = 6) test groups. Blood samples were collected frequently for 210 minutes. Nursing was allowed from 180 to 210 minutes. Plasma glucagon, ACTH, serum insulin, and cortisol concentrations were measured using immunoassays. Results Plasma glucagon concentration decreased relative to baseline at 45, 90, and 180 minutes during the OLT (P = .03), but no differences occurred in other test groups. Nursing stimulated marked increases in plasma glucagon, serum insulin, and glucose concentrations in all test groups (P < .001). Plasma ACTH concentration increased relative to baseline at 180 minutes (P < .05) during fasting and OLT, but no differences occurred in other test groups. Serum cortisol concentration increased relative to baseline during OLT at 180 minutes (P = .04), but no differences occurred in other test groups. Nursing resulted in decreased plasma ACTH and serum cortisol concentrations in all test groups (P < .01). Conclusions and Clinical Importance The endocrine response to enterally and parenterally administered carbohydrates, including the major endocrine response to nursing, suggests that factors in milk other than carbohydrates are strong stimulators (directly or indirectly) of the endocrine pancreas and HPAA.
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Affiliation(s)
- Hannah M Kinsella
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine
| | - Laura D Hostnik
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine
| | - Lindsey M Rings
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine
| | - Jacob M Swink
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine
| | - Teresa A Burns
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine
| | - Ramiro E Toribio
- Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine
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Swink JM, Rings LM, Snyder HA, McAuley RC, Burns TA, Dembek KA, Gilsenan WF, Browne N, Toribio RE. Dynamics of androgens in healthy and hospitalized newborn foals. J Vet Intern Med 2020; 35:538-549. [PMID: 33277956 PMCID: PMC7848305 DOI: 10.1111/jvim.15974] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 01/25/2023] Open
Abstract
Background Information on steroids derived from the adrenal glands, gonads, or fetoplacental unit is minimal in newborn foals. Objective To measure androgen concentrations in serum and determine their association with disease severity and outcome in hospitalized foals. Animals Hospitalized (n = 145) and healthy (n = 80) foals. Methods Prospective, multicenter, cross‐sectional study. Foals of ≤3 days of age from 3 hospitals and horse farms were classified as healthy and hospitalized (septic, sick nonseptic, neonatal maladjustment syndrome [NMS]) based on physical exam, medical history, and laboratory findings. Serum androgen and plasma ACTH concentrations were measured with immunoassays. Data were analyzed by nonparametric methods and univariate analysis. Results Serum dehydroepiandrosterone (DHEA), androstenedione, testosterone, and dihydrotestosterone (DHT) concentrations were higher upon admission in hospitalized foals (P < .05), were associated with nonsurvival, decreased to 4.9‐10.8%, 5.7‐31%, and 30.8‐62.8% admission values in healthy, SNS, and septic foals, respectively (P < .05), but remained unchanged or increased in nonsurviving foals. ACTH:androgen ratios were higher in septic and NMS foals (P < .05). Foals with decreased androgen clearance were more likely to die (odds ratio > 3; P < .05). Conclusions and Clinical Importance Similar to glucocorticoids, mineralocorticoids, and progestagens, increased serum concentrations of androgens are associated with disease severity and adverse outcome in hospitalized newborn foals. In healthy foals, androgens decrease over time, however, remain elevated longer in septic and nonsurviving foals. Androgens could play a role in or reflect a response to disorders such as sepsis or NMS in newborn foals.
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Affiliation(s)
- Jacob M Swink
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Lindsey M Rings
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA.,Rood and Riddle Equine Hospital, Lexington, Kentucky, USA
| | - Hailey A Snyder
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Rachel C McAuley
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Teresa A Burns
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Katarzyna A Dembek
- College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | | | - Nimet Browne
- Hagyard Equine Medical Institute, Lexington, Kentucky, USA
| | - Ramiro E Toribio
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio, USA
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Dembek KA, Johnson LM, Timko KJ, Minuto JS, Hart KA, Barr BS, Toribio RE. Multiple adrenocortical steroid response to administration of exogenous adrenocorticotropic hormone to hospitalized foals. J Vet Intern Med 2019; 33:1766-1774. [PMID: 31111575 PMCID: PMC6639474 DOI: 10.1111/jvim.15527] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 05/08/2019] [Indexed: 12/15/2022] Open
Abstract
Background 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. Animals Hospitalized (n = 34) and healthy (n = 13) foals. Methods In this prospective study, hospitalized foals were categorized into 2 groups using cluster analysis based on adrenal steroids response to ACTH stimulation: Cluster 1 (n = 11) and Cluster 2 (n = 23). After baseline blood sample collection, foals received 10 μg of ACTH with additional samples collected at 30 and 90 minutes after ACTH. Steroid and ACTH concentrations were determined by immunoassays. The area under the curve (AUC) and Delta0‐30 were calculated for each hormone. Results The AUC for cortisol, aldosterone, androstenedione, pregnenolone, 17α‐OH‐progesterone, and progesterone were higher in critically ill (Cluster 1) compared to healthy foals (P < .01). Delta0‐30 for cortisol and 17α‐OH‐progesterone was lower in Cluster 1 (24%, 26.7%) and Cluster 2 (16%, 11.2%) compared to healthy foals (125%, 71%), respectively (P < .05). Foals that died had increased AUC for endogenous ACTH (269 versus 76.4 pg/mL/h, P < .05) accompanied by a low AUC for cortisol (5.5 versus 15.5 μg/dL/h, P < .05), suggesting adrenocortical dysfunction. Conclusion and Clinical Importance The 17α‐OH‐progesterone response to administration of ACTH was a good predictor of disease severity and death in hospitalized foals.
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Affiliation(s)
- Katarzyna A Dembek
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa
| | - Lindsey M Johnson
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | - Kathryn J Timko
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | - Jillian S Minuto
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | - Kelsey A Hart
- Department of Large Animal Medicine, University of Georgia College of Veterinary Medicine, Athens, Georgia
| | - Bonnie S Barr
- Internal Medicine, Rood and Riddle Equine Hospital, Lexington, Kentucky
| | - Ramiro E Toribio
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
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