FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Am J Vet Res / Evaluation of the effects of the opioid agonist morphine on ...
American journal of veterinary research2006; 67(6); 992-997; doi: 10.2460/ajvr.67.6.992

Evaluation of the effects of the opioid agonist morphine on gastrointestinal tract function in horses.

Abstract: To evaluate the effects of morphine administration for 6 days on gastrointestinal tract function in healthy adult horses. Methods: 5 horses. Methods: Horses were randomly allocated into 2 groups in a crossover study. Horses in the treatment group received morphine sulfate at a dosage of 0.5 mg/kg, IV, every 12 hours for 6 days. Horses in the control group received saline (0.9% NaCl) solution at a dosage of 10 mL, IV, every 12 hours for 6 days. Variables assessed included defecation frequency, weight of feces produced, intestinal transit time (evaluated by use of barium-filled spheres and radiographic detection in feces), fecal moisture content, borborygmus score, and signs of CNS excitement and colic. Results: Administration of morphine resulted in gastrointestinal tract dysfunction for 6 hours after each injection. During those 6 hours, mean +/- SD defecation frequency decreased from 3.1 +/- 1 bowel movements in control horses to 0.9 +/- 0.5 bowel movements in treated horses, weight of feces decreased from 4.1 +/- 0.7 kg to 1.1 +/- 0.7 kg, fecal moisture content decreased from 76 +/- 2.7% to 73.5 +/- 2.9%, and borborygmus score decreased from 13.2 +/- 2.9 to 6.3 +/- 3.9. Mean gastrointestinal transit time was also increased, compared with transit times in control horses. Conclusions: Morphine administered at 0.5 mg/kg twice daily decreased propulsive motility and moisture content in the gastrointestinal tract lumen. These effects may predispose treated horses to development of ileus and constipation.
Get Full Text
Publication Date: 2006-06-03 PubMed ID: 16740092DOI: 10.2460/ajvr.67.6.992Google 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
  • Randomized Controlled Trial
  • Research Support
  • Non-U.S. Gov't

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 research article is a study on the effects of morphine on the gastrointestinal function of horses. It concludes that morphine causes decreased motility and moisture in the horse’s digestive tract, potentially leading to constipation or blockages.

Study Design

  • The study was conducted on a total of 5 horses. The horses were randomly allocated to two groups – the treatment group and the control group.
  • For a period of 6 days, the treatment group was administered morphine sulfate. The dosage of morphine administered was 0.5 mg/kg through an intravenous route, twice a day.
  • As a comparison, the control group was given a saline (0.9% Sodium Chloride) solution. The saline solution, also administered through an IV, was at a dosage of 10 mL and given twice a day for 6 days.

Variables Measured

  • The variables that were assessed included defecation frequency, weight of feces produced, intestinal transit time (which was evaluated via radiographic detection using barium-filled spheres), fecal moisture content, borborygmus score (a score that gauges intestinal activity), and signs of central nervous system excitement and colic.

Results

  • The results showed that morphine administration resulted in dysfunction in the gastrointestinal tract for about 6 hours after each injection.
  • During these 6 hours, the study observed a significant decrease in defecation frequency, weight of feces produced, and fecal moisture content. Also, the borborygmus score substantially dropped, indicating lower intestinal activity in the treated horses.
  • In comparison to the control group, the gastrointestinal transit time in the morphine-treated horses increased.

Conclusion

  • The research concluded that administering morphine at 0.5 mg/kg twice daily results in decreased propulsive motility, meaning the movement of content through the digestive tract is slowed down. Similarly, the moisture content in the digestive tract lumen also reduced.
  • Due to these effects, horses treated with morphine could potentially develop issues such as ileus and constipation. Ileus is a disruptive condition where the intestines stop functioning properly, preventing the passage of food.

Cite This Article

APA
Boscan P, Van Hoogmoed LM, Farver TB, Snyder JR. (2006). Evaluation of the effects of the opioid agonist morphine on gastrointestinal tract function in horses. Am J Vet Res, 67(6), 992-997. https://doi.org/10.2460/ajvr.67.6.992

Publication

American journal of veterinary research
ISSN: 0002-9645
NlmUniqueID: 0375011
Country: United States
Language: English
Volume: 67
Issue: 6
Pages: 992-997

Researcher Affiliations

Boscan, Pedro
  • Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Van Hoogmoed, Linda M
    Farver, Thomas B
      Snyder, Jack R

        MeSH Terms

        • Analgesics, Opioid / pharmacology
        • Animals
        • Cross-Over Studies
        • Feces / chemistry
        • Gastrointestinal Contents / drug effects
        • Gastrointestinal Tract / drug effects
        • Gastrointestinal Tract / physiology
        • Gastrointestinal Transit / drug effects
        • Horses / metabolism
        • Male
        • Morphine / pharmacology
        • Water / analysis

        Citations

        This article has been cited 22 times.
        1. Verhaar N, Hoppe S, Grages AM, Hansen K, Neudeck S, Kästner S, Mazzuoli-Weber G. Dexmedetomidine Has Differential Effects on the Contractility of Equine Jejunal Smooth Muscle Layers In Vitro. Animals (Basel) 2023 Mar 10;13(6).
          doi: 10.3390/ani13061021pubmed: 36978562google scholar: lookup
        2. Gough RL, McGovern KF, Bladon BM, Carmichael LA. Caecal dysfunction following standing surgical procedures. Vet Med Sci 2022 Sep;8(5):1930-1935.
          doi: 10.1002/vms3.882pubmed: 35894758google scholar: lookup
        3. Hamamoto-Hardman BD, Steffey EP, Seminoff K, McKemie DS, Kass P, Knych HK. Preliminary study of the pharmacokinetics, tissue distribution, and behavioral and select physiological effects of morphine 6-glucuronide (M6G) following intravenous administration to horses. Can J Vet Res 2022 Jul;86(3):172-180.
          pubmed: 35794968
        4. Salarpour M, Sakhaee E, Samimi AS, Azari O. Comparative evaluation of the sedative and physiological effects of medetomidine alone and in combination with pethidine, morphine, tramadol, and methadone in goats. Vet Med Sci 2022 Jul;8(4):1664-1670.
          doi: 10.1002/vms3.806pubmed: 35353952google scholar: lookup
        5. Yu J, Lin X, Chen H. Study on the Application Effect of Fast Track Surgery Care Combined With Continuous Care After Discharge in Patients With Laparoscopic Cholecystectomy. Front Surg 2022;9:848234.
          doi: 10.3389/fsurg.2022.848234pubmed: 35265663google scholar: lookup
        6. Nannarone S, Giannettoni G, Laurenza C, Giontella A, Moretti G. Methadone or Butorphanol as Pre-Anaesthetic Agents Combined with Romifidine in Horses Undergoing Elective Surgery: Qualitative Assessment of Sedation and Induction. Animals (Basel) 2021 Aug 31;11(9).
          doi: 10.3390/ani11092572pubmed: 34573538google scholar: lookup
        7. Troya-Portillo L, López-Sanromán J, Villalba-Orero M, Santiago-Llorente I. Cardiorespiratory, Sedative and Antinociceptive Effects of a Medetomidine Constant Rate Infusion with Morphine, Ketamine or Both. Animals (Basel) 2021 Jul 13;11(7).
          doi: 10.3390/ani11072081pubmed: 34359209google scholar: lookup
        8. Pezzanite LM, Griffenhagen GM, Krause DM, Hendrickson DA. Retrospective evaluation of association between perioperative antimicrobial protocol and complications following elective equine synovial endoscopy. Vet Med Sci 2021 May;7(3):609-620.
          doi: 10.1002/vms3.447pubmed: 33595201google scholar: lookup
        9. Lashgari NA, Roudsari NM, Zandi N, Pazoki B, Rezaei A, Hashemi M, Momtaz S, Rahimi R, Shayan M, Dehpour AR, Abdolghaffari AH. Current overview of opioids in progression of inflammatory bowel disease; pharmacological and clinical considerations. Mol Biol Rep 2021 Jan;48(1):855-874.
          doi: 10.1007/s11033-020-06095-xpubmed: 33394234google scholar: lookup
        10. Foster A, McSloy A, Monticelli P. Ultrasound-guided psoas compartment and sciatic nerve blocks for pain management of hind limb procedures in the alpaca (Vicugna pacos). Open Vet J 2020 Aug;10(2):120-127.
          doi: 10.4314/ovj.v10i2.1pubmed: 32821656google scholar: lookup
        11. Taylor PM, Hoare HR, de Vries A, Love EJ, Coumbe KM, White KL, Murrell JC. A multicentre, prospective, randomised, blinded clinical trial to compare some perioperative effects of buprenorphine or butorphanol premedication before equine elective general anaesthesia and surgery. Equine Vet J 2016 Jul;48(4):442-50.
          doi: 10.1111/evj.12442pubmed: 25772950google scholar: lookup
        12. Carregaro AB, Freitas GC, Ribeiro MH, Xavier NV, Dória RG. Physiological and analgesic effects of continuous-rate infusion of morphine, butorphanol, tramadol or methadone in horses with lipopolysaccharide (LPS)-induced carpal synovitis. BMC Vet Res 2014 Dec 21;10:966.
          doi: 10.1186/s12917-014-0299-zpubmed: 25528353google scholar: lookup
        13. Elfenbein JR, Robertson SA, MacKay RJ, KuKanich B, Sanchez L. Systemic and anti-nociceptive effects of prolonged lidocaine, ketamine, and butorphanol infusions alone and in combination in healthy horses. BMC Vet Res 2014;10 Suppl 1(Suppl 1):S6.
          doi: 10.1186/1746-6148-10-S1-S6pubmed: 25238633google scholar: lookup
        14. Freitas GC, Carregaro AB, Gehrcke MI, De La Côrte FD, Lara VM, Pozzobon R, Brass KE. Epidural analgesia with morphine or buprenorphine in ponies with lipopolysaccharide (LPS)-induced carpal synovitis. Can J Vet Res 2011 Apr;75(2):141-6.
          pubmed: 21731186
        15. Bodnar RJ. Endogenous opiates and behavior: 2006. Peptides 2007 Dec;28(12):2435-513.
          doi: 10.1016/j.peptides.2007.09.002pubmed: 17949854google scholar: lookup
        16. Maldonado Moreno N, Alves Moreira J, Araujo De Oliveira L, Sanches Gontijo A, Castilho Baldi ML, Rocha Wenceslau R, Beier SL. Analgesic and Gastrointestinal Effects of Methadone in Horses Undergoing Orchiectomy. Animals (Basel) 2025 Aug 11;15(16).
          doi: 10.3390/ani15162358pubmed: 40867687google scholar: lookup
        17. Guzmán JFC, Gontijo AS, Melgaço ES, Faria SA, Baldi MLC, Sousa LN, Wenceslau RR, Fantini P, Xavier ABDS, Beier SL. Analgesic and Gastrointestinal Effects of Morphine in Equines. Animals (Basel) 2025 Feb 17;15(4).
          doi: 10.3390/ani15040571pubmed: 40003052google scholar: lookup
        18. Chiavaccini L, Reed RA, Spadavecchia C. Editorial: Advancements in equine pain management. Front Pain Res (Lausanne) 2025;6:1547764.
          doi: 10.3389/fpain.2025.1547764pubmed: 39974313google scholar: lookup
        19. Sousa LN, Winter IC, Varela DD, Luvison EZ, Guzmán JFC, Machado AMV, Figueiredo RDV, Pena GT, Dos Santos ACS, Faleiros RR, Carvalho AM. Lidocaine's Ineffectiveness in Mitigating Lipopolysaccharide-Induced Pain and Peristaltic Effects in Horses. Animals (Basel) 2024 Nov 2;14(21).
          doi: 10.3390/ani14213147pubmed: 39518869google scholar: lookup
        20. Bacon EK, Donnelly CG, Bellone RR, Haase B, Finno CJ, Velie BD. Preliminary investigation of potential links between pigmentation variants and opioid analgesic effectiveness in horses during cerebrospinal fluid centesis. BMC Vet Res 2024 Jul 12;20(1):311.
          doi: 10.1186/s12917-024-04139-zpubmed: 38997753google scholar: lookup
        21. Reed RA, Berghaus LJ, Reynolds RM, Holmes BT, Krikorian AM, Sakai DM, Ishikawa Y, Knych HK. The pharmacokinetics and pharmacodynamics of fentanyl administered via transdermal patch in horses. Front Pain Res (Lausanne) 2024;5:1373759.
          doi: 10.3389/fpain.2024.1373759pubmed: 38571562google scholar: lookup
        22. Haralambus R, Juri M, Mokry A, Jenner F. The impact of opioid administration on the incidence of postanaesthetic colic in horses. Front Pain Res (Lausanne) 2024;5:1347548.
          doi: 10.3389/fpain.2024.1347548pubmed: 38440199google scholar: lookup
        Subscribe to our newsletter
        Join 99,357 horse owners like you who receive our email updates on horse health and nutrition.