eng Rovedar Journal of Veterinary Physiology and Pathology 2821-0328 2026-09-20 5 3 46 52 10.58803/jvpp.v5i3.94 96 Swastika Sapkota 0 https://orcid.org/0009-0009-8745-7794 Manish Gautam 1 https://orcid.org/0000-0002-8129-9109 Arjun Aryal 2 https://orcid.org/0000-0003-0648-7625 Nepal Polytechnic Institute, Purbanchal University, Nepal Department of Veterinary Physiology and Theriogenology, Paklihawa Campus, Institute of Agriculture and Animal Science, Tribhuvan University, Nepal Senior Veterinary Officer, Central Veterinary Laboratory, Tripureshwar, Nepal Introduction: Ovariohysterectomy in dogs requires safe and effective anesthesia protocols. Nevertheless, the most effective combination and dosage of xylazine and ketamine, with or without adjuncts such as atropine, remain undetermined. The current study aimed to evaluate and compare the effects of xylazine-ketamine and xylazine-ketamine combined with atropine in female dogs undergoing ovariohysterectomy. Materials and methods: Fifteen mongrel female dogs, aged 2-3 years and weighing 15-20 kilograms, were assigned to three groups of five each. Group A received ketamine-xylazine at a 1:2 volume ratio (1 mL + 2 mL) at 1 mL/10 kg of body weight. Group B received the same xylazine-ketamine mixture with atropine added at 0.04-0.05 mg/kg. Group C received xylazine-ketamine at a 1:1 volume ratio (1 mL xylazine + 1 mL ketamine) at 1 mL/10kg of body weight. All groups received the same diazepam-ketamine maintenance anesthesia intravenously. Physical parameters, including heart rate, respiratory rate, rectal temperature, and oxygen saturation (SpO2), were recorded every 10 minutes for up to 60 minutes. Blood samples to evaluate hematological parameters, including red blood cell (RBC), white blood cell (WBC), platelets, hemoglobin (Hb), and packed cell volume (PCV), were collected before induction and again 30 minutes after induction. Results: Heart rate and respiratory rate increased for up to 30 minutes across all treatment groups, with fewer fluctuations observed in Group B. Body temperature initially increased, then decreased, while SpO2 initially decreased and gradually increased in all treatment groups. Nevertheless, these fluctuations were not statistically significant in Group B compared to the baseline values. No significant changes in WBC, platelet count, or PCV were observed in groups B and C compared with baseline values. The RBC and Hb levels were significantly reduced across all groups compared with baseline. Conclusion: The present results demonstrated that the xylazine-ketamine-atropine combination provided a more stable anesthetic protocol during ovariohysterectomy in dogs, as the physical parameters indicated safer anesthetic conditions. https://jvpp.rovedar.com/index.php/JVPP/article/view/94 Anesthesia Hematological parameter Ketamine Physiological parameter Xylazine