FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Equine veterinary journal2023; doi: 10.1111/evj.14030

Influence of feeding and other factors on adrenocorticotropin concentration and thyrotropin-releasing hormone stimulation test in horses and ponies.

Abstract: The basal (bACTH) and post-thyrotropin-releasing hormone stimulation concentration of adrenocorticotropin (pACTH) are recommended for diagnosis of pituitary pars intermedia dysfunction (PPID). Many factors influence bACTH (e.g., disease, age, month) and some affect the results only in autumn (e.g., breed, colour, sex). There are discrepancies about the impact of feeding on b/pACTH. Objective: To determine whether feeding, month, age, breed, colour, sex and body condition score affect b/pACTH. Methods: Prospective crossover. Methods: Sixty-one animals were divided into groups: healthy, PPID, treated-PPID. The b/pACTH was measured three times (1 mg protirelin; blood collection after 10 min; mid-November to mid-July) after different feedings: fasting, hay, hay + grain. Friedman's test was applied to evaluate the influence of feeding on b/pACTH and linear mixed model to evaluate impact of further factors. Results: The b/pACTH was not significantly affected by feeding (p = 0.7/0.5). The bACTH was lowest in healthy (29.3 pg/mL, CI 9-49.5 pg/mL) and highest in PPID-group (58.9 pg/mL, CI 39.7-78.1 pg/mL). The pACTH was significantly lower in healthy (396.7 pg/mL, CI 283.2-510.1 pg/mL) compared to PPID (588.4 pg/mL, CI 480.7-696.2 pg/mL) and treated-PPID group (683.1 pg/mL, CI 585.9-780.4 pg/mL), highest in July (881.2 pg/mL, CI 626.3-1136.3 pg/mL) and higher in grey (723.5 pg/mL, CI 577.5-869.4 pg/mL) than other colours (338.7 pg/mL, CI 324.8-452.5 pg/mL). The size of effect for those variables was >0.5. Conclusions: Small number of animals, subsequent bACTH measurements were significantly lower in each horse. Conclusions: There was no evidence that feeding influences the b/pACTH. There was evidence that pergolide affects the bACTH but it had little effect on pACTH. Further investigation of the impact of month and coat colour on b/pACTH is warranted to better interpret the results.
© 2023 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
Get Full Text
Publication Date: 2023-11-27 PubMed ID: 38010866DOI: 10.1111/evj.14030Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research examines multiple factors and their impact on adrenocorticotropin hormone levels in horses and ponies, with a particular focus on the role of feeding. The study concludes that feeding does not significantly impact these hormone levels, but other factors like disease status, month, and coat colour do.

Objective and Methodology

  • The primary objective of the research was to examine whether parameters such as feeding, month, age, breed, colour, sex, and body condition score influence the concentration of adrenocorticotropin hormone (both basal and post-thyrotropin-releasing hormone stimulation concentrations).
  • Sixty-one animals were involved in the study, split into three categories: those in healthy condition, those with pituitary pars intermedia dysfunction (PPID), and those being treated for PPID.
  • Over a period extending from mid-November to mid-July, blood samples were taken from the animals three times after different feeding regimes – after fasting, after hay feed, and after a combination of hay and grain feed.
  • The researchers used statistical tests like Friedman’s test and linear mixed model to evaluate the influence of different variables.

Results

  • The results indicated that feeding doesn’t significantly impact the levels of adrenocorticotropin hormone (p=0.7/0.5).
  • The study found that the hormone levels were lowest in the healthy group and highest in the untreated PPID group. For the treated PPID group, the post-stimulation levels of the hormone were significantly higher compared to the healthy group.
  • These hormone levels were also observed to be highest in July and higher in grey-coloured horses compared to those with other coat colours.

Conclusions

  • Given that the sample size was small, further studies with larger samples are needed to confirm these findings.
  • The research concluded without finding evidence that feeding influences hormone levels. However, it did find that the disease condition and its treatment affect the hormone levels, specifically the basal adrenocorticotropin hormone.
  • Moreover, the study found that the month in which the hormone test is done and the horse’s coat colour do impact hormone levels, suggesting further studies in these areas will enhance understanding.

Cite This Article

APA
Drozdzewska K, Winter J, Barton AK, Merle R, Gehlen H. (2023). Influence of feeding and other factors on adrenocorticotropin concentration and thyrotropin-releasing hormone stimulation test in horses and ponies. Equine Vet J. https://doi.org/10.1111/evj.14030

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Drozdzewska, Karolina
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.
Winter, Judith
  • Synlab.vet GmbH, Berlin, Germany.
Barton, Ann Kristin
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.
Merle, Roswitha
  • Institute of Veterinary Epidemiology and Biostatistics, Freie Universität Berlin, Berlin, Germany.
Gehlen, Heidrun
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.

References

This article includes 54 references
  1. Hart K, Durham A, Frank N, McGowan C, Schott H, Stewart A. Recommendation for the diagnosis and treatment of pituitary pars intermedia dysfunction (PPID).. Equine Endocrinology Group 2021.
  2. McGowan TW, Pinchbeck GP, McGowan CM. Prevalence, risk factors and clinical signs predictive for equine pituitary pars intermedia dysfunction in aged horses.. Equine Vet J 2013;45:74-79.
  3. Miller MA, Pardo ID, Jackson LP, Moore GE, Sojka JE. Correlation of pituitary histomorphometry with adrenocorticotrophic hormone response to domperidone administration in the diagnosis of equine pituitary pars intermedia dysfunction.. Vet Pathol 2008;45:26-38.
  4. Beech J, McFarlane D, Lindborg S, Sojka JE, Boston RC. α-Melanocyte-stimulating hormone and adrenocorticotropin concentrations in response to thyrotropin-releasing hormone and comparison with adrenocorticotropin concentration after domperidone administration in healthy horses and horses with pituitary pars intermedia dysfunction.. J Am Vet Med Assoc 2011;238:1305-1315.
  5. Beech J, Boston R, Lindborg S, Russell GE. Adrenocorticotropin concentration following administration of thyrotropin-releasing hormone in healthy horses and those with pituitary pars intermedia dysfunction and pituitary gland hyperplasia.. J Am Vet Med Assoc 2007;231:417-426.
  6. Beech J, Boston R, Lindborg S. Comparison of cortisol and ACTH responses after administration of thyrotropin releasing hormone in normal horses and those with pituitary pars intermedia dysfunction.. J Vet Intern Med 2011;25:1431-1438.
  7. Gough S, Duz M, Rendle D. Is there merit in utilising the TRH stimulation test in horses with an equivocal ACTH concentration?. Equine Vet J 2019;51:24.
  8. Horn R, Stewart AJ, Jackson KV, Dryburgh EL, Medina-Torres CE, Bertin FR. Clinical implications of using adrenocorticotropic hormone diagnostic cutoffs or reference intervals to diagnose pituitary pars intermedia dysfunction in mature horses.. J Vet Intern Med 2021;35:560-570.
  9. Jacob SI, Geor RJ, Weber PSD, Harris PA, McCue ME. Effect of dietary carbohydrates and time of year on ACTH and cortisol concentrations in adult and aged horses.. Domest Anim Endocrinol 2018;63:15-22.
  10. Diez de Castro E, Lopez I, Cortes B, Pineda C, Garfia B, Aguilera-Tejero E. Influence of feeding status, time of the day, and season on baseline adrenocorticotropic hormone and the response to thyrotropin releasing hormone-stimulation test in healthy horses.. Domest Anim Endocrinol 2014;48:77-83.
  11. Restifo MM, Frank N, Hermida P, Sanchez-Londono A. Effects of withholding feed on thyrotropin-releasing hormone stimulation test results and effects of combined testing on oral sugar test and thyrotropin-releasing hormone stimulation test results in horses.. Am J Vet Res 2016;77:738-748.
  12. Al-Damluji S, Iveson T, Thomas JM, Pendlebury DJ, Rees LH, Besser GM. Food-induced cortisol secretion is mediated by central alpha-1 adrenoceptor modulation of pituitary ACTH secretion.. Clin Endocrinol (Oxf) 1987;26:629-636.
  13. Copas VE, Durham AE. Circannual variation in plasma adrenocorticotropic hormone concentrations in the UK in normal horses and ponies, and those with pituitary pars intermedia dysfunction.. Equine Vet J 2012;44:440-443.
  14. Durham AE, Clarke BR, Potier JFN, Hammarstrand R, Malone GL. Clinically and temporally specific diagnostic thresholds for plasma ACTH in the horse.. Equine Vet J 2021;53:250-260.
  15. Stewart AJ, Hackett E, Bertin FR, Towns TJ. Cortisol and adrenocorticotropic hormone concentrations in horses with systemic inflammatory response syndrome.. J Vet Intern Med 2019;33:2257-2266.
  16. Gehlen H, Jaburg N, Merle R, Winter J. Can endocrine dysfunction be reliably tested in aged horses that are experiencing pain?. Animals (Basel) 2020;10(8):1426.
  17. Durham A, Shreeve H. Horse factors influencing the seasonal increase in plasma ACTH secretion.. Dorothy Russell Havemeyer Foundation International Equine Endocrinology Summit 2017. p. 36-37.
  18. McFarlane D, Maxwell LK. Establishment of a reference interval for plasma ACTH concentration in aged horses.. Dorothy Russell Havemeyer Foundation International Equine Endocrinology Summit 2017. p. 18.
  19. Durham AE, Potier JF, Huber L. The effect of month and breed on plasma adrenocorticotropic hormone concentrations in equids.. Vet J 2022;286:105857.
  20. Guo J, Simmons WK, Herscovitch P, Martin A, Hall KD. Striatal dopamine D2-like receptor correlation patterns with human obesity and opportunistic eating behavior.. Mol Psychiatry 2014;19:1078-1084.
  21. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body fat percentage in mares.. Equine Vet J 1983;15:371-372.
  22. Schott H, Andrews F, Durham A, Frank N, Hart K, Kritchevsky J. Recommendation for the diagnosis and treatment of pituitary pars intermedia dysfunction (PPID).. Equine Endocrinology Group 2021.
  23. Banse HE, Whitehead AE, McFarlane D, Chelikani PK. Markers of muscle atrophy and impact of treatment with pergolide in horses with pituitary pars intermedia dysfunction and muscle atrophy.. Domest Anim Endocrinol 2021;76:106620.
  24. Innera M, Petersen AD, Desjardins DR, Steficek BA, Rosser EJ Jr, Schott HC 2nd. Comparison of hair follicle histology between horses with pituitary pars intermedia dysfunction and excessive hair growth and normal aged horses.. Vet Dermatol 2013;24:212-217. e46-7.
  25. Kirkwood NC, Hughes KJ, Stewart AJ. Prospective case series of clinical signs and adrenocorticotrophin (ACTH) concentrations in seven horses transitioning to pituitary pars intermedia dysfunction (PPID).. Vet Sci 2022;9(10):572.
  26. Humphreys S, Kass PH, Magdesian KG, Goodrich E, Berryhill E. Seasonal variation of endogenous adrenocorticotropic hormone concentrations in healthy non-geriatric donkeys in northern California.. Front Vet Sci 2022;9:981920.
  27. Sullivan GM, Feinn R. Using effect size-or why the P value is not enough.. J Grad Med Educ 2012;4:279-282.
  28. Thane K, Uricchio C, Frank N. Effect of early or late blood sampling on thyrotropin releasing hormone stimulation test results in horses.. J Vet Intern Med 2022;36:770-777.
  29. Sanchez-Londono A, Frank N, Grubbs S, Hermida P, Hofmeister E. Evaluation of different doses of thyrothropin releasing hormone in miniature horses.. Proceedings of the 4th Global Equine Endocrine Symposium, Gut Ising 2020. p. 24.
  30. Schorn C, Failing K, Fey K. Comparison of two TRH doses in PPID patients.. Proceedings of the 4th Global Equine Endocrine Symposium, Gut Ising 2020. p. 16.
  31. Boujon CE, Bestetti GE, Meier HP, Straub R, Junker U, Rossi GL. Equine pituitary adenoma: a functional and morphological study.. J Comp Pathol 1993;109:163-178.
  32. Kienzle E, Zehnder C, Pfister K, Gerhards H, Sauter-Louis C, Harris P. Field study on risk factors for free fecal water in pleasure horses.. J Equine Vet 2016;44:32-36.
  33. Stewart AJ, Yuen KY, Hinrichsen S, Horn R, Dryburgh E, Bertin FR. Effect of sample handling on adrenocorticotropic hormone (ACTH) concentrations following thyrotropin-releasing hormone (TRH) stimulations in horses.. Proceedings of the 4th Global Equine Endocrine Symposium, Gut Ising 2020. p. 28.
  34. McGilvray TA, Knowles EJ, Harris PA, Menzies-Gow NJ. Comparison of immunofluorescence and chemiluminescence assays for measuring ACTH in equine plasma.. Equine Vet J 2020;52:709-714.
  35. McCann JS, Caudle AB, Thompson FN, Stuedemann JA, Heusner GL, Thompson DL Jr. Influence of endophyte-infected tall fescue on serum prolactin and progesterone in gravid mares.. J Anim Sci 1992;70:217-223.
  36. Kam YN, McKenzie K, Coyle M, Bertin FR. Repeatability of a thyrotropin-releasing hormone stimulation test for diagnosis of pituitary pars intermedia dysfunction in mature horses.. J Vet Intern Med 2021;35:2885-2890.
  37. Miller AB, Loynachan AT, Bush HM, Hart KA, Barker VD, Campana-Emard AG. Effects of pituitary pars intermedia dysfunction and Prascend (pergolide tablets) treatment on endocrine and immune function in horses.. Domest Anim Endocrinol 2021;74:106531.
  38. McFarlane D, Banse H, Knych HK, Maxwell LK. Pharmacokinetic and pharmacodynamic properties of pergolide mesylate following long-term administration to horses with pituitary pars intermedia dysfunction.. J Vet Pharmacol Ther 2017;40:158-164.
  39. Perkins GA, Lamb S, Erb HN, Schanbacher B, Nydam DV, Divers TJ. Plasma adrenocorticotropin (ACTH) concentrations and clinical response in horses treated for equine Cushing's disease with cyproheptadine or pergolide.. Equine Vet J 2002;34:679-685.
  40. Banse H, McFarlane D. Comparison of seasonal TRH stimulation test results in horses with PPID treated with Prascend® or placebo.. Dorothy Russell Havemeyer Foundation International Equine Endocrinology Summit 2017. p. 16-17.
  41. Tatum RC, McGowan CM, Ireland JL. Efficacy of pergolide for the management of equine pituitary pars intermedia dysfunction: a systematic review.. Vet J 2020;266:105562.
  42. Durham AE. The effect of pergolide mesylate on adrenocorticotrophic hormone responses to exogenous thyrotropin releasing hormone in horses.. Vet J 2022;285:105831.
  43. Altmeyer P, Holzmann H, Stohr L, Koch HJ. The relationship between alpha-MSH level and coat color in white Camarque horses.. J Invest Dermatol 1984;82:199-201.
  44. Mc Gowan TW, Pinchbeck GP, McGowan CM. Evaluation of basal plasma alpha-melanocyte-stimulating hormone and adrenocorticotrophic hormone concentrations for the diagnosis of pituitary pars intermedia dysfunction from a population of aged horses.. Equine Vet J 2013;45:66-73.
  45. McFarlane D. Advantages and limitations of the equine disease, pituitary pars intermedia dysfunction as a model of spontaneous dopaminergic neurodegenerative disease.. Ageing Res Rev 2007;6:54-63.
  46. Gehlen H, Twickel S, Stockle S, Weber C, Bartmann CP. Diagnostic orientation values for ACTH and other parameters for clinically healthy donkeys and mules (insulin, triglycerides, glucose, fructosamines, and gamma-GT).. J Anim Physiol Anim Nutr (Berl) 2020;104:679-689.
  47. Fredrick J, McFarlane D. ACTH release following TRH stimulation in thrifty horses compared to metabolically normal horses.. J Vet Intern Med 2014;28:976-1134.
  48. Bamford NJ, Harris PA, Bailey SR. Circannual variation in plasma adrenocorticotropic hormone concentrations and dexamethasone suppression test results in standardbred horses, Andalusian horses and mixed-breed ponies.. Aust Vet J 2020;98:616-621.
  49. McFarlane D, Paradis MR, Zimmel D, Sykes B, Brorsen BW, Sanchez A. The effect of geographic location, breed, and pituitary dysfunction on seasonal adrenocorticotropin and alpha-melanocyte-stimulating hormone plasma concentrations in horses.. J Vet Intern Med 2011;25:872-881.
  50. Couetil L, Paradis MR, Knoll J. Plasma adrenocorticotropin concentration in healthy horses and in horses with clinical signs of hyperadrenocorticism.. J Vet Intern Med 1996;10:1-6.
  51. Potier J, Durham A. The effect of latitude and breed on circannual ACTH concentrations in the UK.. Proceedings of the 4th Global Equine Endocrine Symposium, Gut Ising 2020. p. 31.
  52. Fredrick J, McFarlane D, Yang F. Is the metabolically thrifty horse at greater risk of PPID?. Proceedings of the Equine Geriatric Workshop II Dorothy Russell Havemeyer and 3rd Equine Endocrine Summit, Middleburg 2014.
  53. Vorster DM, Wang W, Kemp KL, Bamford NJ, Bertin FR. Clinical implications of imprecise sampling time for 10- and 30-min thyrotropin-releasing hormone stimulation tests in horses. Equine Vet J. 2023. https://doi.org/10.1111/evj.13991
    doi: 10.1111/evj.13991google scholar: lookup
  54. Haffner JC, Hoffman RM, Grubbs ST. The effect of trailering and dentistry on resting adrenocorticotropic hormone concentration in horses.. Proceedings of the 4th Global Equine Endocrine Symposium, Gut Ising 2020. p. 6.

Citations

This article has been cited 0 times.
Subscribe to our newsletter
Join 99,911 horse owners like you who receive our email updates on horse health and nutrition.