Assessing behavioral response in a Florida manatee administered Tramadol for a spinal injury.

This study investigated the use of behavioral monitoring to determine the presence or absence of pain and efficacy of pain therapy administered to a Florida manatee critically injured by a boat strike. The study subject was a 4-year-old Florida manatee (Trichechus manatus latirostris) undergoing rehabilitative care for a severed and displaced spinal column at the Miami Seaquarium. Tramadol, a pain medication commonly used in veterinary medicine, was administered for a period of 7 weeks, while a behavioral ethogram was developed and used to determine whether drug administration was associated with specific behaviors, including increases and decreases in activity. Serum samples were collected from the subject to determine the pharmacokinetics of Tramadol in the Florida manatee to better understand the rate of absorption, distribution, and duration of the drug’s efficacy. The results of the study indicated that 100 mg of Tramadol was an effective dosage for the Florida manatee, and 3.5 hours after ingestion the drug was identified at a concentration of 21 ng/ml for Tramadol and 7 ng/ml for M1, a metabolite of Tramadol, without producing potentially dangerous side effects such as intestinal upset. Serum samples collected 22 hours after initial ingestion of the dosage identified no detectable levels of the medication, indicating that Tramadol administered at this particular dosage must be provided daily to maintain efficacy. Results of behavioral observations indicated that there was a significant increase in both the frequency and duration of the behaviors “resting on bottom of pool” and “crunch” while not receiving pain medication when compared to receiving Tramadol, and both of these behaviors may be indicative of a pain response. Thus, the results of this study indicated that Tramadol administered in specific dosages may be effective in mitigating pain in manatees, and a behavioral ethogram may be a valuable, non-invasive tool for use in assessing pain in the Florida manatee, a Federally and state-listed endangered species