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Canadian Journal of Veterinary Research logoLink to Canadian Journal of Veterinary Research
. 1998 Jul;62(3):218–223.

A thermal threshold assay to measure the nociceptive response to morphine sulphate in cattle.

L C Machado Filho 1, J F Hurnik 1, K K Ewing 1
PMCID: PMC1189479  PMID: 9684052

Abstract

A thermal threshold measurer (TTM) apparatus was developed and tested in 12 dry, nonpregnant, culled cows with the purpose of measuring the thermal nociceptive threshold and of finding the response to morphine sulphate dosages. The cows received a cumulative dose (from 0.00 to 0.40 mg/kg BW) of morphine sulphate through a catheter in the jugular vein. The interval between doses was 20 min, and a nociceptive test was performed 15 min after each injection. The TTM device consisted of a 60 W halogen bulb mounted in a 15 cm PVC tube, with a 0.6 s response time probe attached to its end, connected to a thermocouple. The probe measured the response temperature on the skin over the middle phalanges on the dorsum of the forefoot. The radiating heat stimulus from the bulb was instantaneously terminated with the foot-lift response of the tested animal. The nociceptive response to the 0.00 mg/kg dose was considered the baseline and subsequent measurements were expressed in difference from it. Data were evaluated in a regression analysis using the GLM procedure. A significant elevation (P < 0.0001) in the nociceptive threshold of the cows with cumulative dosing of morphine sulphate was noticed. A high variability (P < 0.0001) in the response among animals was also detected, suggesting that a 2-step dose of morphine sulphate is necessary to achieve a certain degree of induced analgesia in all cows. The nociceptive assay described, using the TTM device, was able to detect an elevation of the thermal threshold of cows due to morphine sulphate induced analgesia. An increase in locomotory behaviour or other side effects due to morphine sulphate were not noticed.

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Selected References

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  1. Abbott F. V., Franklin K. B., Connell B. The stress of a novel environment reduces formalin pain: possible role of serotonin. Eur J Pharmacol. 1986 Jul 15;126(1-2):141–144. doi: 10.1016/0014-2999(86)90750-8. [DOI] [PubMed] [Google Scholar]
  2. Armstrong J. D., Johnson B. H. Agonists of endogenous opioid peptides suppress LH, and stimulate cortisol and growth hormone during the follicular phase in heifers. J Endocrinol. 1989 Apr;121(1):11–17. doi: 10.1677/joe.0.1210011. [DOI] [PubMed] [Google Scholar]
  3. Kamerling S. G., Dequick D. J., Weckman T. J., Tobin T. Dose-related effects of ethylketazocine on nociception, behaviour and autonomic responses in the horse. J Pharm Pharmacol. 1986 Jan;38(1):40–45. doi: 10.1111/j.2042-7158.1986.tb04464.x. [DOI] [PubMed] [Google Scholar]
  4. Kamerling S., Wood T., DeQuick D., Weckman T. J., Tai C., Blake J. W., Tobin T. Narcotic analgesics, their detection and pain measurement in the horse: a review. Equine Vet J. 1989 Jan;21(1):4–12. doi: 10.1111/j.2042-3306.1989.tb02081.x. [DOI] [PubMed] [Google Scholar]
  5. Kristal M. B., Thompson A. C., Grishkat H. L. Placenta ingestion enhances opiate analgesia in rats. Physiol Behav. 1985 Oct;35(4):481–486. doi: 10.1016/0031-9384(85)90127-1. [DOI] [PubMed] [Google Scholar]
  6. Kyles A. E., Waterman A. E., Livingston A. Antinociceptive activity of midazolam in sheep. J Vet Pharmacol Ther. 1995 Feb;18(1):54–60. doi: 10.1111/j.1365-2885.1995.tb00551.x. [DOI] [PubMed] [Google Scholar]
  7. Ludbrook G., Grant C., Upton R., Penhall C. A method for frequent measurement of sedation and analgesia in sheep using the response to a ramped electrical stimulus. J Pharmacol Toxicol Methods. 1995 Feb;33(1):17–22. doi: 10.1016/1056-8719(94)00051-5. [DOI] [PubMed] [Google Scholar]
  8. Nolan A., Livingston A., Morris R., Waterman A. Techniques for comparison of thermal and mechanical nociceptive stimuli in the sheep. J Pharmacol Methods. 1987 Mar;17(1):39–49. doi: 10.1016/0160-5402(87)90035-0. [DOI] [PubMed] [Google Scholar]
  9. Nolan A., Waterman A. E., Livingston A. The correlation of the thermal and mechanical antinociceptive activity of pethidine hydrochloride with plasma concentrations of the drug in sheep. J Vet Pharmacol Ther. 1988 Mar;11(1):94–102. doi: 10.1111/j.1365-2885.1988.tb00126.x. [DOI] [PubMed] [Google Scholar]
  10. Peck D. D., Thompson F. N., Jernigan A., Kiser T. E. Effect of morphine on serum gonadotropin concentrations in postpartum beef cows. J Anim Sci. 1988 Nov;66(11):2930–2936. doi: 10.2527/jas1988.66112930x. [DOI] [PubMed] [Google Scholar]
  11. Rund L. A., Leshin L. S., Thompson F. N., Kiser T. E. Effects of suckling and of a long interval after ovariectomy on hypothalamo-hypophyseal responsiveness to naloxone, morphine and GnRH in beef cows. Theriogenology. 1992 Jul;38(1):73–83. doi: 10.1016/0093-691x(92)90219-h. [DOI] [PubMed] [Google Scholar]
  12. Rushen J., De Passillé A. M., Schouten W. Stereotypic behavior, endogenous opioids, and postfeeding hypoalgesia in pigs. Physiol Behav. 1990 Jul;48(1):91–96. doi: 10.1016/0031-9384(90)90267-8. [DOI] [PubMed] [Google Scholar]

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