Antinociceptive efficacy of intramuscular administration of morphine sulfate and butorphanol tartrate in tegus (Salvator merianae)

Abstract

OBJECTIVE To evaluate the antinociceptive efficacy of IM morphine sulfate or butorphanol tartrate administration in tegus (Salvator merianae). ANIMALS 6 healthy juvenile (12- to 24-month-old) tegus (mean ± SD body weight, 1,484 ± 473 g). PROCEDURES In a crossover study design, tegus were randomly assigned to treatment order, with a minimum washout period of 15 days between treatments. Each of 5 treatments was administered IM in a forelimb: saline (0.9% NaCl) solution (0.5 mL), morphine sulfate (5 or 10 mg/kg), or butorphanol tartrate (5 or 10 mg/kg). A withdrawal latency test was used to evaluate antinociception, with a noxious thermal stimulus applied to the plantar surface of the hind limb before (0 hours; baseline) and 0.5, 1, 2, 3, 4, 6, 12, and 24 hours after each treatment. Observers were unaware of treatment received. RESULTS With saline solution, mean hind limb withdrawal latencies (interval to limb withdrawal from the thermal stimulus) remained constant, except at 12 hours. Tegus had higher than baseline mean withdrawal latencies between 0.5 and 1 hour and at 12 hours with morphine at 5 mg/kg and between 1 and 12 hours with morphine at 10 mg/kg. With butorphanol at 5 and 10 mg/kg, tegus maintained withdrawal responses similar to baseline at all assessment points. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that morphine, but not butorphanol, provided antinociception at 5 and 10 mg/kg in tegus as measured by thermal noxious stimulus testing. These data supported the hypothesis that μ-opioid (but not κ-opioid) receptor agonists provide antinociception in reptiles.

Use of Rodent Sedation Tests to Evaluate Midazolam and Flumazenil in Green Iguanas (Iguana iguana)

“…The antinociceptive effects of the drugs were assessed as described previously. 23 Briefly, a noxious thermal stimulus was provided by exposing a hindlimb to a radiant heat source set (Ugo Basile, Gemonio, Italy) at an intensity of 70 (245 ± 7 mW/cm 2 ; 45 to 47 °C) for a maximum of 30 s to prevent tissue burns. The iguanas were restrained in an opaque acrylic box (60 cm × 13 cm × 14 cm) on the palmar test device.…”

A Critical Review on the Pharmacodynamics and Pharmacokinetics of Non-steroidal Anti-inflammatory Drugs and Opioid Drugs Used in Reptiles

“… ( Sladky et al., 2008 ) - - - Green iguana ✗ ( Greenacre et al., 2006 ) ✓ ( Greenacre et al., 2006 ) - - ✗ ( Greenacre et al., 2006 ) - - - Prehensile-tailed skink - - ✗ ( Gamble, 2008 ) - - - - - Tegus - N.R. ( Leal et al., 2017 ) - - N.R. ( Leal et al., 2017 ) - - - Black-bellied slider turtle - - ✗ ( Kaminishi et al., 2019 ) - - - - - Loggerhead sea turtle - - - - - - - ✗ ( Norton et al., 2015 ) Red-eared slider turtle ✓ ( Kummrow et al., 2008 ; Mans et al., 2012 ) ✓ ( Kinney et al., 2011 ; Sladky et al., 2007 ) ✗ ( Kaminishi et al., 2019 ) ✗ ( Hawkins et al., 2019 ; Kummrow et al., 2008 ) ✓ ( Kinney et al., 2011 ; Sladky et al., 2007 ) - ✓ ( Giorgi et al., 2014 ) ...…”

“… ( Leal et al., 2017 ) - - N.R. ( Leal et al., 2017 ) - - - Black-bellied slider turtle - - ✗ ( Kaminishi et al., 2019 ) - - - - - Loggerhead sea turtle - - - - - - - ✗ ( Norton et al., 2015 ) Red-eared slider turtle ✓ ( Kummrow et al., 2008 ; Mans et al., 2012 ) ✓ ( Kinney et al., 2011 ; Sladky et al., 2007 ) ✗ ( Kaminishi et al., 2019 ) ✗ ( Hawkins et al., 2019 ; Kummrow et al., 2008 ) ✓ ( Kinney et al., 2011 ; Sladky et al., 2007 ) - ✓ ( Giorgi et al., 2014 ) ✓ ( Baker et al., 2011 ) Speke's hinged tortoise - - - - N.R. ( Wambugu et al., 2010 ) N.R.…”

Antinociceptive and physiological effects of subcutaneously administration of fentanyl in Trachemyssp. (Testudines: Emydidae)

“…Compared with butorphanol and morphine [13], [25], it has higher analgesic capacity and shorter duration, since the other two drugs remain active in the animal organism for more than 24 hours. In Salvatormerinae, between morphine and butorphanol, only morphine promoted antinociception at doses of 5 and 10 mg/kg [26]. Similar to fentanyl, tapentadol, another μ-opioid receptor agonist, has also demonstrated effective analgesia in T. scriptaafter a single intramuscular application at a concentration of 5 mg/kg [27], [28].…”