Analyze Diet
BMC veterinary research2023; 19(1); doi: 10.1186/s12917-023-03654-9

Comparison of two sedation protocols for long electroretinography in horses using the Koijman electrode.

Abstract: In modern times, horses are utilized not only for labour and transportation purposes but also for recreational activities such as competition and pleasure riding. In these various pursuits, the role of vision plays a crucial role. Electroretinography is the most used test to diagnose diseases of the retinal outer segment. There is a wide variety of devices to perform the electroretinography differing one from each other in the corneal electrode and the light stimulation. The Koijman electrode has been tested in dogs but not in horses. The main purpose of this study was to compare electroretinography parameters from horses sedated with detomidine alone or in combination with butorphanol, during a standardized protocol using the Koijman electrode and RETI-port® system. Seven mares were allocated to the detomidine and detomidine plus butorphanol group in a randomised, controlled, crossover study. Friedman and Willcoxon-signed ranked tests were used to compare the electroretinogram parameters. A Student's t-test was used to compare differences in the number of artefacts to valid values ratio obtained under both sedation protocols.
Publication Date: 2023-08-04 PubMed ID: 37537621PubMed Central: PMC10401785DOI: 10.1186/s12917-023-03654-9Google 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.
  • Clinical Trial Protocol
  • 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.

Horses, in the present day, are engaged in various activities that require good vision. One common test to detect diseases affecting the back part of the eye (retina) in animals is called electroretinography. Various devices with different specifications are available to conduct this test. One such device, the Koijman electrode, has been tried in dogs but not in horses. This study intends to use the Koijman electrode and another device called RETI-port® to study the eyes of horses sedated in two different ways.

Objective:

The main aim is to compare the results of the electroretinography test in horses that were sedated using either detomidine alone or a combination of detomidine and butorphanol.

Study Design:

Seven female horses (mares) were sedated using both methods at different times (crossover design). The effects of the sedatives on the test results were then analyzed.

Methods:

Statistical tests (Friedman, Wilcoxon-signed ranked tests, and Student’s t-test) were used to compare the results from both sedation methods.

Results:

  1. After being kept in the dark (to adjust their eyes to low light), the best readings were taken after 16 minutes for both groups.
  2. There were no significant differences in the main test results between the two sedation methods.
  3. However, during a specific part of the test where both rods and cones (types of light-detecting cells in the retina) were being evaluated, all horses made head movements, causing many disturbances (artefacts) in the readings.
  4. The group sedated with both detomidine and butorphanol seemed to have slightly fewer disturbances and stayed sedated for a longer time, although this difference was not statistically significant.

Conclusions:

Sedating horses with either detomidine alone or combined with butorphanol seems suitable when using the Koijman electrode and RETI-port® for a standardized extended testing protocol, but some adjustments might be needed to optimize the results.

In simple terms, the study tried to see which sedation method is better when testing the eyes of horses using specific equipment. Both methods were found to be usable, but there might be a slight edge to using both drugs combined.

Cite This Article

APA
Ignacio C, Del Mar LM, Marta B, Sina Z, Vicent R, Aloma MF. (2023). Comparison of two sedation protocols for long electroretinography in horses using the Koijman electrode. BMC Vet Res, 19(1). https://doi.org/10.1186/s12917-023-03654-9

Publication

ISSN: 1746-6148
NlmUniqueID: 101249759
Country: England
Language: English
Volume: 19
Issue: 1

Researcher Affiliations

Ignacio, Corradini
  • Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Tirant lo Blanc, 7, Alfara del Patriarca, Valencia, 46115, Spain.
  • School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Nr Loughborough, LE12 5RD, England, UK.
Del Mar, López-Murcia María
  • Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Tirant lo Blanc, 7, Alfara del Patriarca, Valencia, 46115, Spain.
Marta, Barba
  • Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Tirant lo Blanc, 7, Alfara del Patriarca, Valencia, 46115, Spain.
Sina, Zebarjadian
  • Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Tirant lo Blanc, 7, Alfara del Patriarca, Valencia, 46115, Spain.
Vicent, Rodilla
  • Departmento de Farmacia, Facultad de Ciencias de la Salud, Instituto de Ciencias Biomédicas, Universidad Cardenal Herrera-CEU, CEU Universities, Santiago Ramón y Cajal, s/n., Alfara del Patriarca, Valencia, 46115, Spain.
Aloma, Mayordomo-Febrer
  • Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Tirant lo Blanc, 7, Alfara del Patriarca, Valencia, 46115, Spain. aloma.mayordomo@uchceu.es.

MeSH Terms

  • Horses
  • Animals
  • Female
  • Dogs
  • Butorphanol
  • Electroretinography / veterinary
  • Hypnotics and Sedatives
  • Cross-Over Studies
  • Imidazoles
  • Electrodes
  • Clinical Trials, Veterinary as Topic

Grant Funding

  • #IDOC18-13 / Universidad Cardenal Herrera-CEU, CEU Universities, Valencia, Spain

Conflict of Interest Statement

The authors declare no competing interests.

References

This article includes 41 references
  1. Ben-Shlomo G, Plummer C, Barrie K, Brooks D. Characterization of the normal dark adaptation curve of the horse.. Vet Ophthalmol 2012 Jan;15(1):42-5.
  2. Ekesten B, Komáromy AM, Ofri R, Petersen-Jones SM, Narfström K. Guidelines for clinical electroretinography in the dog: 2012 update.. Doc Ophthalmol 2013 Oct;127(2):79-87.
    pubmed: 23728902doi: 10.1007/s10633-013-9388-8google scholar: lookup
  3. Sandmeyer LS, Bellone RR, Archer S, Bauer BS, Nelson J, Forsyth G, Grahn BH. Congenital stationary night blindness is associated with the leopard complex in the Miniature Horse.. Vet Ophthalmol 2012 Jan;15(1):18-22.
  4. Nunnery C, Pickett JP, Zimmerman KL. Congenital stationary night blindness in a Thoroughbred and a Paso Fino.. Vet Ophthalmol 2005 Nov-Dec;8(6):415-9.
  5. Ben-Shlomo G. The Equine Fundus.. Vet Clin North Am Equine Pract 2017 Dec;33(3):499-517.
    pubmed: 29103559doi: 10.1016/j.cveq.2017.08.003google scholar: lookup
  6. Pollio D, Michau TM, Weaver E, Kuebelbeck KL. Electroretinographic changes after intravenous lipid emulsion therapy in a dog and a foal with ivermectin toxicosis.. Vet Ophthalmol 2018 Jan;21(1):82-87.
    pubmed: 27440451doi: 10.1111/vop.12410google scholar: lookup
  7. Allbaugh RA, Ben-Shlomo G, Whitley RD. Electroretinogram evaluation of equine eyes with extensive 'bullet-hole' fundic lesions.. Vet Ophthalmol 2014 Jul;17 Suppl 1:129-33.
    pubmed: 24995631doi: 10.1111/vop.12169google scholar: lookup
  8. McCulloch DL, Marmor MF, Brigell MG, Hamilton R, Holder GE, Tzekov R, Bach M. ISCEV Standard for full-field clinical electroretinography (2015 update).. Doc Ophthalmol 2015 Feb;130(1):1-12.
    pubmed: 25502644doi: 10.1007/s10633-014-9473-7google scholar: lookup
  9. Komáromy AM, Andrew SE, Sapp HL Jr, Brooks DE, Dawson WW. Flash electroretinography in standing horses using the DTL microfiber electrode.. Vet Ophthalmol 2003 Mar;6(1):27-33.
  10. Church ML, Norman JC. Electroretinogram responses of the normal thoroughbred horse sedated with detomidine hydrochloride.. Vet Ophthalmol 2012 Sep;15 Suppl 2:77-83.
  11. Wouters L, de Moor A, Moens Y. Rod and cone components in the electroretinogram of the horse.. Zentralbl Veterinarmed A 1980 Jun;27(4):330-8.
  12. Gilger B, Stoppini R. Equine ocular examination: routine and advanced diagnostic techniques.. 2011;pp. 1–51.
  13. Rosa M, Landgraf Botteon P, Pereira J, Brooks D, Dias Rosa M. Evaluation of equine electroretinographic responses by using two different electrodes and four different Alpha-2 agonist sedatives.. Rev Bras Med Vet 2014;36(4):367–74.
  14. Zeiler GE. A review of clinical approaches to antagonism of alpha 2 -adrenoreceptor agonists in the horse.. Equine Vet Educ 2015 Jan;27(1):48–54.
  15. de Grauw J, van Loon T. Clinical effects of two doses of butorphanol with detomidine for intravenous premedication of healthy warmblood horses.. Vet Anaesth Analg 2020 Sep;47(5):681-685.
    pubmed: 32792271doi: 10.1016/j.vaa.2019.11.010google scholar: lookup
  16. Dodam JR, Branson KR, Martin DD. Effects of intramuscular sedative and opioid combinations on tear production in dogs.. Vet Ophthalmol 1998;1(1):57-59.
  17. England GC, Clarke KW, Goossens L. A comparison of the sedative effects of three alpha 2-adrenoceptor agonists (romifidine, detomidine and xylazine) in the horse.. J Vet Pharmacol Ther 1992 Jun;15(2):194-201.
  18. Frigerio MA, Gómez Cisneros D, Santiago Llorente I, Manso-Díaz G, López-Sanromán J. A kinematic comparison of the locomotor pattern of horses sedated with detomidine alone and in combination with low doses of butorphanol.. Equine Vet J 2019 Nov;51(6):825-830.
    pubmed: 30866108doi: 10.1111/evj.13098google scholar: lookup
  19. Kruluc P, Nemec A. Electroencephalographic and electromyographic changes during the use of detomidine and detomidine-butorphanol combination in standing horses.. Acta Vet Hung 2006 Mar;54(1):35-42.
    pubmed: 16613024doi: 10.1556/avet.54.2006.1.4google scholar: lookup
  20. Lavoie JP, Phan ST, Blais D. Effects of a combination of detomidine and butorphanol on respiratory function in horses with or without chronic obstructive pulmonary disease.. Am J Vet Res 1996 May;57(5):705-9.
    pubmed: 8723886
  21. Leonardi F, Costa GL, Stagnoli A, Zubin E, Boschi P, Sabbioni A, Simonazzi B. The effect of intramuscular dexmedetomidine-butorphanol combination on tear production in dogs.. Can Vet J 2019 Jan;60(1):55-59.
    pmc: PMC6294015pubmed: 30651651
  22. Leonardi F, Costa GL, Dubau M, Sabbioni A, Simonazzi B, Angelone M. Effects of intravenous romifidine, detomidine, detomidine combined with butorphanol, and xylazine on tear production in horses.. Equine Vet Educ 2020 Aug 21;32(S11):53–7.
  23. Nyman G, Marntell S, Edner A, Funkquist P, Morgan K, Hedenstierna G. Effect of sedation with detomidine and butorphanol on pulmonary gas exchange in the horse.. Acta Vet Scand 2009 May 7;51(1):22.
    pmc: PMC2694811pubmed: 19422714doi: 10.1186/1751-0147-51-22google scholar: lookup
  24. Robertson JT, Muir WW. A new analgesic drug combination in the horse.. Am J Vet Res 1983 Sep;44(9):1667-9.
    pubmed: 6625320
  25. Selk Ghaffari M, Brooks DE, Sabzevari A, Ghamsari SM, Mansoor Lakooraj H, Shad H. Effects of Intravenous Detomidine on Schirmer tear Test results in clinically normal horses.. J Equine Vet Sci 2017 Aug;55:97–9.
  26. Sandmeyer LS, Bauer BS, Grahn BH. Diagnostic ophthalmology.. Can Vet J 2012 Jan;53(1):96-8.
    pmc: PMC3239160pubmed: 22753974
  27. Robertson SA. Standing sedation and pain management for ophthalmic patients.. Vet Clin North Am Equine Pract 2004 Aug;20(2):485-97.
    pubmed: 15271436doi: 10.1016/j.cveq.2004.04.005google scholar: lookup
  28. Interlandi C, Calapai G, Nastasi B, Mannucci C, Morici M, Costa GL. Effects of Atipamezole on the analgesic activity of Butorphanol in rats.. J Exot Pet Med 2017 Oct;26(4):290–3.
  29. Costa GL, Cristarella S, Quartuccio M, Interlandi C. Anti-nociceptive and sedative effects of romifidine, tramadol and their combination administered intravenously slowly in ponies.. Vet Anaesth Analg 2015 Mar;42(2):220-5.
    pubmed: 25039663doi: 10.1111/vaa.12210google scholar: lookup
  30. Costa GL, Leonardi F, Interlandi C, Spadola F, Fisichella S, Macrì F, Nastasi B, Macrì D, Ferrantelli V, Di Pietro S. Levobupivacaine Combined with Cisatracurium in Peribulbar Anaesthesia in Cats Undergoing Corneal and Lens Surgery.. Animals (Basel) 2023 Jan 1;13(1).
    pmc: PMC9817947pubmed: 36611778doi: 10.3390/ani13010170google scholar: lookup
  31. Jeong MB, Son WG, Park YW, Kim SE, Park SA, Seo KM. Comparison of two electroretinography systems used in dogs: the HMsERG and the RETIport.. J Vet Med Sci 2011 Apr;73(4):431-8.
    pubmed: 21099150doi: 10.1292/jvms.10-0197google scholar: lookup
  32. Kim HA, Jeong MB, Yi NY, Park SA, Kim WT, Kim SE, Chae JM, Seo KM. Effects of stimulus intensity for electroretinogram in conscious Miniature Schnauzers.. J Vet Med Sci 2008 Aug;70(8):857-9.
    pubmed: 18772566doi: 10.1292/jvms.70.857google scholar: lookup
  33. Maehara S, Itoh Y, Hoshino S, Hayashi M, Ito Y. Dark adaptation time in canine electroretinography using a contact lens electrode with a built-in light source.. J Vet Med Sci 2015 Oct;77(10):1335-8.
    pmc: PMC4638308pubmed: 26074341doi: 10.1292/jvms.14-0647google scholar: lookup
  34. Yu HA, Jeong MB, Park SA, Kim WT, Kim SE, Chae JM, Yi NY, Seo KM. The determination of dark adaptation time using electroretinography in conscious miniature Schnauzer dogs.. J Vet Sci 2007 Dec;8(4):409-14.
    pmc: PMC2868158pubmed: 17993756doi: 10.4142/jvs.2007.8.4.409google scholar: lookup
  35. Dugdale AH, Taylor PM. Equine anaesthesia-associated mortality: where are we now?. Vet Anaesth Analg 2016 May;43(3):242-55.
    pubmed: 26970940doi: 10.1111/vaa.12372google scholar: lookup
  36. Joyner RL, Liu CC, Cremer J, Carter RT, Lewin AC. Intraocular pressure following four different intravenous sedation protocols in normal horses.. Equine Vet J 2021 May;53(3):612-617.
    pubmed: 32844457doi: 10.1111/evj.13336google scholar: lookup
  37. Mayordomo-Febrer A, Rubio M, Martínez-Gassent M, López-Murcia MM. Effects of morphine-alfaxalone-midazolam premedication, alfaxalone induction and sevoflurane maintenance on intraocular pressure and tear production in dogs.. Vet Rec 2017 May 13;180(19):474.
    pubmed: 28062846doi: 10.1136/vr.104040google scholar: lookup
  38. Freeman KS, Good KL, Kass PH, Park SA, Nestorowicz N, Ofri R. Effects of chemical restraint on electroretinograms recorded sequentially in awake, sedated, and anesthetized dogs.. Am J Vet Res 2013 Jul;74(7):1036-42.
    pubmed: 23802676doi: 10.2460/ajvr.74.7.1036google scholar: lookup
  39. Susanti L, Kang S, Park S, Park E, Park Y, Kim B, Kim S, Seo K. Effect of Three Different Sedatives on Electroretinography Recordings in Domestic Pigeons (Columba livia).. J Avian Med Surg 2019 Jun 1;33(2):115-122.
    pubmed: 31251498doi: 10.1647/2018-351google scholar: lookup
  40. Del Sole MJ, Nejamkin P, Cavilla V, Schaiquevich P, Moreno L. Comparison of two sedation protocols for short electroretinography in cats.. J Feline Med Surg 2018 Feb;20(2):172-178.
    pubmed: 28379112doi: 10.1177/1098612x17703011google scholar: lookup
  41. Narfström K, Ekesten B, Rosolen SG, Spiess BM, Percicot CL, Ofri R. Guidelines for clinical electroretinography in the dog.. Doc Ophthalmol 2002 Sep;105(2):83-92.
    pubmed: 12462438doi: 10.1023/a:1020524305726google scholar: lookup

Citations

This article has been cited 1 times.
  1. Roth LSV, McGreevy P. Horse vision through two lenses: Tinbergen's Four Questions and the Five Domains. Front Vet Sci 2025;12:1647911.
    doi: 10.3389/fvets.2025.1647911pubmed: 40895790google scholar: lookup