Cortisol Concentration, Pain and Sedation Scale in Free Roaming Dogs Treated With Carprofen After Ovariohysterectomy

Background and Aim: One of the topic issues in animal welfare activities is the free roaming dog welfare especially in developing countries such as Serbia. The way of controlling population of free roaming dogs is their reproduction with the method of “Catch-Neuter-Release.” This complex process consists of capturing free roaming dogs in public areas, sterilizing, and returning them to the public area from which they were temporarily removed. Ovariohysterectomy present the period with a high intensity of stress reaction since many veterinarians in Serbia do not use analgesia for this group of dogs. The aim of this study was to compare the serum cortisol concentration before and after ovariohysterectomy and the level of post-operative pain and sedation in a group of free roaming female dogs treated with carprofen after surgical intervention and in a group with no treatment.
Materials and Methods: The study was performed on a total of 20 female dogs under the program for free roaming dog control. Free-roaming dogs were captured in public areas by the communal animal hygiene service and were transported between 30 and 45 min to the clinic of a veterinary practice. Treatment began at 10:00 h on the next day and the bitches were kept in cages until they were returned to public locations from which they were temporarily removed to be sterilized. The G2 group received before closing the incision line carprofen in one dosage of 4 mg/kg given by subcutaneous injection into the scruff. Rescue protocol with carprofen was provided for G1 after 24 h following ovariohysterectomy same dosage as G2. Blood (2 ml) was collected from the cephalic vein of each dog in disposable plastic syringes, containing heparin (1:1000) 4 times: Before ovariohysterectomy, 30, 120 min and 24 h following ovariohysterectomy. Cortisol concentration was determined by enzyme-linked immunosorbent assay. The multifactorial pain and sedation scale were used for the assessment of pain and sedation.
Results: In both groups, the lowest values of serum cortisol concentration were obtained before ovariohysterectomy. Cortisol levels in both groups were significantly higher (p<0.01) 30 and 120 min after ovariohysterectomy and showed a decreasing trend toward the end of the observation period (24 h). The results obtained 15 and 30 min after the surgical intervention have revealed a statistically significant difference between the groups (p<0.05) showing that female dogs treated with carprofen had a lower value on the pain scale and a higher value on the sedation scale compared to the group with no treatment.
Conclusion: Carprofen provides both a restful consequence of sedation and a rapid return to a more normal physiological and behavioral state in dogs after ovariohysterectomy.