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Veterinary research communications1983; 6(4); 249-264; doi: 10.1007/BF02214921

Equine anhidrosis: a review of pathophysiologic mechanisms.

Abstract: Anhidrosis is loss of the ability to sweat. The problem is seen in horses kept in a hot humid climate, and it may cause severe impairment of thermoregulation in the equine athlete. British Thoroughbreds imported to her tropical colonies are the earliest recorded cases, and since then the syndrome has come to be described as one of Thoroughbreds, usually performance athletes, undergoing acclimatization to heat and humidity. A recent epidemiologic study of cases in Florida has shown, however, that many different breeds, and long time inhabitants of a hot climate, may be affected. Equine sweat glands are of the apocrine type, and sweating is stimulated by direct local release of epinephrine from adrenergic nerve endings and by circulating epinephrine. Lack of sweating could be due to a number of possible flaws in a sequence from central nervous stimulation through sweat stimulation and secretion to delivery of sweat to the skin surface. The most likely possibilities are inadequate sweat gland response due to habituation of receptors to a high circulating level of epinephrine and occlusion of the sweat ducts by keratin plugs. Hormonal or metabolic imbalance may play a role both in the onset and secondary signs associated with anhidrosis.
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Publication Date: 1983-09-01 PubMed ID: 6359664DOI: 10.1007/BF02214921Google Scholar: Lookup
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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.

The article is a review of the causes and potential mechanisms behind anhidrosis, a condition in which horses lose their ability to sweat, that often impacts equine athletes living in hot and humid climates. This condition can severely hinder their ability to regulate body temperature.

Understanding Anhidrosis in Horses

  • Anhidrosis is a condition that causes horses to lose the ability to sweat. This impairment is often seen in equine athletes who live in hot, humid climates and can seriously impact their ability to regulate their body temperature.
  • While the condition has been recorded in horses for centuries, with one of the earliest documented cases being British Thoroughbreds imported to tropical colonies, recent research in Florida has shown that the condition can affect many different breeds and even horses who have lived in a hot climate for a prolonged period.

Causes and Mechanisms of Anhidrosis

  • The article explores the possible mechanisms that could lead to anhidrosis in horses. Normally, equine sweat glands are stimulated to produce sweat by the local release of a hormone called epinephrine from nerve endings and its circulation in the blood.
  • The inability to sweat could be a result of various flaws along the path from the initial stimulation of the central nervous system to the eventual secretion and delivery of sweat to the skin’s surface.
  • Potential causes suggested by the article include a diminished response from the sweat glands due to habituation of the receptors to constantly high levels of epinephrine, or the obstruction of sweat ducts by keratin plugs.

Hormonal Imbalance and Anhidrosis

  • Moreover, the authors suggest that hormonal or metabolic imbalances could play a part in both initiating anhidrosis and also in secondary indicators associated with the condition. Thus, the article emphasizes the need for further research to understand this complex condition and to develop effective treatments.

Cite This Article

APA
Warner A, Mayhew IG. (1983). Equine anhidrosis: a review of pathophysiologic mechanisms. Vet Res Commun, 6(4), 249-264. https://doi.org/10.1007/BF02214921

Publication

Veterinary research communications
ISSN: 0165-7380
NlmUniqueID: 8100520
Country: Switzerland
Language: English
Volume: 6
Issue: 4
Pages: 249-264

Researcher Affiliations

Warner, A
    Mayhew, I G

      MeSH Terms

      • Acclimatization
      • Adrenergic Fibers / physiology
      • Animals
      • Body Temperature Regulation
      • Climate
      • Epinephrine / pharmacology
      • Florida
      • Horse Diseases / physiopathology
      • Horses
      • Humidity
      • Hypohidrosis / physiopathology
      • Hypohidrosis / veterinary
      • Physical Exertion
      • Sweat / analysis
      • Sweat Glands / anatomy & histology
      • Sweat Glands / drug effects
      • Sweat Glands / innervation
      • Sweat Glands / physiopathology

      References

      This article includes 65 references
      1. FELLER RP, HALE HB. HUMAN URINARY CATECHOLAMINES IN RELATION TO CLIMATE.. J Appl Physiol 1964 Jan;19:37-9.
        pubmed: 14104288doi: 10.1152/jappl.1964.19.1.37google scholar: lookup
      2. EVANS CL, SMITH DF. On sweating in the horse.. J Physiol 1954 Nov 29;126(2):45-6P.
        pubmed: 13222335
      3. Hindson TC. Ascorbic acid for prickly heat.. Lancet 1968 Jun 22;1(7556):1347-8.
        pubmed: 4172653doi: 10.1016/s0140-6736(68)92038-2google scholar: lookup
      4. Morris HG, Rusnak SA, Selner JC, Barzens K, Barnes J. Comparative effects of ephedrine on adrenergic responsiveness in normal and asthmatic subjects.. J Allergy Clin Immunol 1978 May;61(5):294-302.
        pubmed: 205566doi: 10.1016/0091-6749(78)90050-7google scholar: lookup
      5. EVANS CL, NISBET AM, ROSS KA. A histological study of the sweat glands of normal and dry-coated horses.. J Comp Pathol 1957 Oct;67(4):397-405.
        pubmed: 13481174doi: 10.1016/s0368-1742(57)80039-3google scholar: lookup
      6. SHELLEY WB. Miliaria.. J Am Med Assoc 1953 Jun 20;152(8):670-3.
        pubmed: 13044605doi: 10.1001/jama.1953.03690080014004google scholar: lookup
      7. Anderson MG, Aitken MM. Biochemical and physiological effects of catecholamine administration in the horse.. Res Vet Sci 1977 May;22(3):357-60.
        pubmed: 877431
      8. Jenkinson DM. On the classification of sweat glands and the question of the existence of an apocrine secretory process.. Br Vet J 1967 Jul;123(7):311-6.
        pubmed: 4863812doi: 10.1016/s0007-1935(17)39908-6google scholar: lookup
      9. Rose RJ, Arnold KS, Church S, Paris R. Plasma and sweat electrolyte concentrations in the horse during long distance exercise.. Equine Vet J 1980 Jan;12(1):19-22.
        pubmed: 7363879doi: 10.1111/j.2042-3306.1980.tb02290.xgoogle scholar: lookup
      10. Carlson GP, Mansmann RA. Serum electrolyte and plasma protein alterations in horses used in endurance rides.. J Am Vet Med Assoc 1974 Aug 1;165(3):262-4.
        pubmed: 4845679
      11. Knochel JP. Environmental heat illness. An eclectic review.. Arch Intern Med 1974 May;133(5):841-64.
        pubmed: 4821779
      12. LADELL WS. Disorders due to heat.. Trans R Soc Trop Med Hyg 1957 May;51(3):189-207; discussion, 207-16.
        pubmed: 13443009doi: 10.1016/0035-9203(57)90017-2google scholar: lookup
      13. DOBSON RL. The effect of repeated episodes of profuse sweating on the human eccrine sweat glands.. J Invest Dermatol 1960 Sep;35:195-8.
        pubmed: 13723299
      14. Toor M, Agmon J, Zahavi I, Wurzel M, Rosenfeld JB. Potassium depletion in permanent in-habitants of hot areas.. Isr J Med Sci 1967 Jan-Feb;3(1):149-50.
        pubmed: 6030417
      15. Förström L, Goldyne ME, Winkelmann RK. IgE in human eccrine sweat.. J Invest Dermatol 1975 Mar;64(3):156-7.
        pubmed: 1117175doi: 10.1111/1523-1747.ep12533312google scholar: lookup
      16. Brooks SM, McGowan K, Bernstein IL, Altenau P, Peagler J. Relationship between numbers of beta adrenergic receptors in lymphocytes and disease severity in asthma.. J Allergy Clin Immunol 1979 Jun;63(6):401-6.
        pubmed: 221557doi: 10.1016/0091-6749(79)90213-6google scholar: lookup
      17. Hindson TC, Worsley DE. The effects of administration of ascorbic acid in experimentally induced miliaria and hypohidrosis in volunteers.. Br J Dermatol 1969 Mar;81(3):226-7.
        pubmed: 5775074doi: 10.1111/j.1365-2133.1969.tb16013.xgoogle scholar: lookup
      18. Smiles KA, Robinson S. Regulation of sweat secretion during positive and negative work.. J Appl Physiol 1971 Mar;30(3):409-12.
        pubmed: 5544122doi: 10.1152/jappl.1971.30.3.409google scholar: lookup
      19. Jenkinson DM, Montgomery I, Elder HY. Studies on the nature of the peripheral sudomotor control mechanism.. J Anat 1978 Mar;125(Pt 3):625-39.
        pubmed: 640964
      20. Bartter FC, Gill JR Jr, Frolich JC. Bartter's syndrome.. Adv Nephrol Necker Hosp 1977;7:191-8.
        pubmed: 96673
      21. Frewin DB, Eakins KE, Downey JA, Bhattacherjee F. Postaglandin-like activity in human eccrine sweat.. Aust J Exp Biol Med Sci 1973 Oct;51(5):701-2.
        pubmed: 4799108doi: 10.1038/icb.1973.65google scholar: lookup
      22. Robertshaw D. Proceedings: Neural and humoral control of apocrine glands.. J Invest Dermatol 1974 Jul;63(1):160-7.
        pubmed: 4152036doi: 10.1111/1523-1747.ep12679280google scholar: lookup
      23. Ferris TF. Prostaglandins, potassium, and Bartter's syndrome.. J Lab Clin Med 1978 Nov;92(5):663-8.
        pubmed: 361914
      24. Jenkinson DM, Mabon RM, Manson W. Sweat proteins.. Br J Dermatol 1974 Feb;90(2):175-81.
        pubmed: 4819135doi: 10.1111/j.1365-2133.1974.tb06382.xgoogle scholar: lookup
      25. Henderson WR, Shelhamer JH, Reingold DB, Smith LJ, Evans R 3rd, Kaliner M. Alpha-adrenergic hyper-responsiveness in asthma.. N Engl J Med 1979 Mar 22;300(12):642-7.
        pubmed: 216913doi: 10.1056/NEJM197903223001203google scholar: lookup
      26. McCaffrey TV, Wurster RD, Jacobs HK, Euler DE, Geis GS. Role of skin temperature in the control of sweating.. J Appl Physiol Respir Environ Exerc Physiol 1979 Sep;47(3):591-7.
        pubmed: 533754doi: 10.1152/jappl.1979.47.3.591google scholar: lookup
      27. Jenkinson DM, Robertshaw D. Studies on the nature of sweat gland 'fatigue' in the goat.. J Physiol 1971 Jan;212(2):455-65.
        pubmed: 4100840doi: 10.1113/jphysiol.1971.sp009335google scholar: lookup
      28. Paillard M. Effects of aldosterone on renal handling of sodium, potassium and hydrogen ions.. Adv Nephrol Necker Hosp 1977;7:83-104.
        pubmed: 96680
      29. Förström L, Goldyne ME, Winkelmann RK. Prostaglandin activity in human eccrine sweat.. Prostaglandins 1974 Sep 25;7(6):459-64.
        pubmed: 4415343doi: 10.1016/0090-6980(74)90090-2google scholar: lookup
      30. Lefkowitz RJ. Direct binding studies of adrenergic receptors: biochemical, physiologic, and clinical implications.. Ann Intern Med 1979 Sep;91(3):450-8.
        pubmed: 38720doi: 10.7326/0003-4819-91-3-450google scholar: lookup
      31. Robertshaw D, Whittow GC. The effect of hyperthermia and localized heating of the anterior hypothalamus on the sympatho-adrenal system of the ox (Bos taurus).. J Physiol 1966 Nov;187(2):351-60.
        pubmed: 5972176doi: 10.1113/jphysiol.1966.sp008094google scholar: lookup
      32. Fox RH, Goldsmith R, Hampton IF, Hunt TJ. Heat acclimatization by controlled hyperthermia in hot-dry and hot-wet climates.. J Appl Physiol 1967 Jan;22(1):39-46.
        pubmed: 6017651doi: 10.1152/jappl.1967.22.1.39google scholar: lookup
      33. Sato K, Nishiyama A, Kobayashi M. Mechanical properties and functions of the myoepithelium in the eccrine sweat gland.. Am J Physiol 1979 Sep;237(3):C177-84.
        pubmed: 38671doi: 10.1152/ajpcell.1979.237.3.C177google scholar: lookup
      34. Morris HG, Rusnak SA, Selner JC, Barzens K, Barnes J. Adrenergic desensitization in leukocytes of normal and asthmatic subjects.. J Cyclic Nucleotide Res 1977 Dec;3(6):439-46.
        pubmed: 203616
      35. Lindeman RD. Hypokalemia: causes, consequences and correction.. Am J Med Sci 1976 Jul-Aug;272(1):5-17.
        pubmed: 786013doi: 10.1097/00000441-197607000-00002google scholar: lookup
      36. Bligh J. A thesis concerning the processes of secretion and discharge of sweat.. Environ Res 1967 Jun;1(1):28-45.
        pubmed: 4882290doi: 10.1016/0013-9351(67)90004-7google scholar: lookup
      37. Elder HY, Jenkinson DM, Montgomery I. Structural changes in the glands during sweating in ungulates [proceedings].. J Physiol 1977 Dec;273(2):39P-40P.
        pubmed: 599441
      38. Jenkinson DM, Montgomery I, Elder HY. The ultrastructure of the sweat glands of the ox, sheep and goat during sweating and recovery.. J Anat 1979 Aug;129(Pt 1):117-40.
        pubmed: 511758
      39. Peter J, Wyndham CH. Activity of the human eccrine sweat gland during exercise in a hot humid environment before and after acclimatization.. J Physiol 1966 Dec;187(3):583-94.
        pubmed: 16783913doi: 10.1113/jphysiol.1966.sp008110google scholar: lookup
      40. EVANS CL, SMITH DF, WEIL-MALHERBE H. The relation between sweating and the catechol content of the blood in the horse.. J Physiol 1956 Jun 28;132(3):542-52.
        pubmed: 13332592doi: 10.1113/jphysiol.1956.sp005547google scholar: lookup
      41. HELLMANN K. Cholinesterase and amine oxidase in the skin: a histochemical investigation.. J Physiol 1955 Sep 28;129(3):454-63.
        pubmed: 13264109doi: 10.1113/jphysiol.1955.sp005370google scholar: lookup
      42. Smith JS, Mayhew IG. Horner's syndrome in large animals.. Cornell Vet 1977 Oct;67(4):529-42.
        pubmed: 25087303
      43. DOBSON RL, LOBITZ WC Jr. Some histochemical observations on the human eccrine sweat glands. IV. The recovery from the effects of profuse sweating.. J Invest Dermatol 1958 Oct;31(4):207-13.
        pubmed: 13588112doi: 10.1038/jid.1958.105google scholar: lookup
      44. Robertshaw D, Taylor CR. Sweat gland function of the donkey (Equus asinus).. J Physiol 1969 Nov;205(1):79-89.
        pubmed: 5347721doi: 10.1113/jphysiol.1969.sp008952google scholar: lookup
      45. Nardone DA, McDonald WJ, Girard DE. Mechanisms in hypokalemia: clinical correlation.. Medicine (Baltimore) 1978 Sep;57(5):435-46.
        pubmed: 355775doi: 10.1097/00005792-197809000-00003google scholar: lookup
      46. Griffin TB, Mailbach HI, Sulzberger MB. Miliaria and anhidrosis. II. The relationships between miliaria and anhidrosis in man.. J Invest Dermatol 1967 Oct;49(4):379-85.
        pubmed: 6058498
      47. SHELLEY WB, HORVATH PN, PILLSBURY DM. Anhidrosis. An etiologic interpretation.. Medicine (Baltimore) 1950 Sep;29(3):195-224.
        pubmed: 14779746
      48. Johnson KG. Sweat gland function in isolated perfused skin.. J Physiol 1975 Sep;250(3):633-49.
        pubmed: 1177153doi: 10.1113/jphysiol.1975.sp011074google scholar: lookup
      49. Warner AE, Mayhew IG. Equine anhidrosis: a survey of affected horses in Florida.. J Am Vet Med Assoc 1982 Mar 15;180(6):627-9.
        pubmed: 7068500
      50. Smith F. Note on the Composition of the Sweat of the Horse.. J Physiol 1890 Nov;11(6):497-503.
        pubmed: 16991935doi: 10.1113/jphysiol.1890.sp000350google scholar: lookup
      51. Schaumburg-Lever G, Lever WF. Secretion from human apocrine glands: an electron microscopic study.. J Invest Dermatol 1975 Jan;64(1):38-41.
        pubmed: 1110304doi: 10.1111/1523-1747.ep12540893google scholar: lookup
      52. JIRKA M, KOTAS J. Some observations on the chemical composition of horse sweat.. J Physiol 1959 Jun 23;147(1):74-7.
        pubmed: 13673385doi: 10.1113/jphysiol.1959.sp006222google scholar: lookup
      53. Francis KT, MacGregor R 3rd. Effect of exercise in the heat on plasma renin and aldosterone with either water or a potassium-rich electrolyte solution.. Aviat Space Environ Med 1978 Mar;49(3):461-5.
        pubmed: 637803
      54. Gordon BI, Maibach HI. On the mechanism of the inactive eccrine human sweat gland.. Arch Dermatol 1968 Jan;97(1):66-8.
        pubmed: 5634447
      55. Sulzberger MB, Griffin TB. Induced miliaria, postmiliarial hypohidrosis, and some potential sequelae.. Arch Dermatol 1969 Feb;99(2):145-51.
        pubmed: 4884045
      56. SELDIN DW, WELT LG, CORT JH. The role of sodium salts and adrenal steroids in the production of hypokalemic alkalosis.. Yale J Biol Med 1956 Dec;29(3):229-47.
        pubmed: 13409923
      57. Jenkinson DM, Blackburn PS. The distribution of nerves, nonoamine oxidase and cholinesterase in the skin of the horse.. Res Vet Sci 1968 Mar;9(2):165-9.
        pubmed: 5651192
      58. Snow DH. Identification of the receptor involved in adrenaline mediated sweating in the horse.. Res Vet Sci 1977 Sep;23(2):246-7.
        pubmed: 200999
      59. Sorensen VW, Prasad G. On the fine structure of horse sweat glands.. Z Anat Entwicklungsgesch 1973 Mar 20;139(2):173-83.
        pubmed: 4352229doi: 10.1007/BF00523636google scholar: lookup
      60. Davis JO, Freeman RH. Mechanisms regulating renin release.. Physiol Rev 1976 Jan;56(1):1-56.
        pubmed: 1108062doi: 10.1152/physrev.1976.56.1.1google scholar: lookup
      61. ROBINSON S, KINCAID RK, RHAMY RK. Effect of salt deficiency on the salt concentration in sweat.. J Appl Physiol 1950 Aug;3(2):55-62.
        pubmed: 14774322doi: 10.1152/jappl.1950.3.2.55google scholar: lookup
      62. Purohit RC, Nachreiner RF, Humburg JM, Norwood GL, Beckett SD. Effect of exercise, phenylbutazone, and furosemide on the plasma renin activity and angiotensin I in horses.. Am J Vet Res 1979 Jul;40(7):986-90.
        pubmed: 507503
      63. Evans CL. Physiological mechanisms that underlie sweating in the horse.. Br Vet J 1966 Mar;122(3):117-23.
        pubmed: 5909025
      64. Cryer PE. Physiology and pathophysiology of the human sympathoadrenal neuroendocrine system.. N Engl J Med 1980 Aug 21;303(8):436-44.
        pubmed: 6248784doi: 10.1056/NEJM198008213030806google scholar: lookup
      65. Sato K. The physiology, pharmacology, and biochemistry of the eccrine sweat gland.. Rev Physiol Biochem Pharmacol 1977;79:51-131.
        pubmed: 21440doi: 10.1007/BFb0037089google scholar: lookup

      Citations

      This article has been cited 1 times.
      1. van der Graaf L, Leigh W, Szmatoła T, Roberts K, Ryan S, Brown B, Van Buren S, Finno CJ, Petersen JL. A missense mutation in the KCNE4 gene is not predictive of equine anhidrosis. Anim Genet 2025 Feb;56(1):e70004.
        doi: 10.1111/age.70004pubmed: 39953936google scholar: lookup
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