Object of research - broken bones, festering wounds, peritonitis and breast tumors in dogs, abdominal wall hernias in pigs and different clinical forms of purulent-necrotic processes in the field of fingers in cattle. The purpose of the study - study of clinical and pathogenetic role of nitric oxide for surgical pathology of inflammatory origin in animals of different species and correction levels in the body to optimize the treatment of purulent peritonitis and course of reparative osteogenesis in dogs accelerate healing of wounds in pigs. Research methods - clinical, radiological, laparoscopic, morphological (erythrocytes, leukocytes, platelets, circulating endothelial cells) hemostatic (platelet aggregation, fibrinogen, fibrinolysis) and biochemical (nitric oxide, hemoglobin, malonic dyaldehid, calcium, phosphorus, bone isoenzyme of alkaline phosphatase). Scientific novelty of the work: first clinical study the pathogenic role of nitric oxide for surgical pathology of inflammatory origin in animals of different species. It is shown that reducing NO and t-PA, an imbalance in the system of vascular-platelet hemostasis lead to the development of endothelial dysfunction by orthopedic disease in cows, herniotomy in pigs, surgical infections and fractures of long bones in dogs. On this basis, reasonable use after herniotomy in pigs and osteosynthesis in dogs drug Imuno-depo, and in purulent peritonitis in dogs - 5% solution of L-arginine to increase NO levels in the blood, prevent endothelial dysfunction and accelerate the healing of the wounds at 1,5 times, seam fractures - in 1.3 and shortening treatment of peritonitis in 1.4 times. Proposed: the treatment of surgical pathology in animals to adjust the level of nitric oxide and optimization during the inflammatory-regenerative process used drug Imuno-depo dose of 0.5 ml/10 kg body weight once a day at intervals of 24 hours to cure animals. To shorten the treatment of purulent peritonitis in dogs and reduction of adhesions in the abdominal cavity complement complex therapeutic measures intravenous 5% solution of L-arginine at a dose of 300 mg/kg once a day at intervals of 24 hours to cure animals. Introduced: the results are used in scientific and practical work in teaching the course of general and special veterinary surgery on the faculties of higher educational institutions III-IV levels of accreditation. Developed guidelines approved by the scientific-methodical council of State veterinary and phytosanitary service of Ukraine and adopted for implementation in practice of veterinary medicine. Fild (industry) of use: Veterinary Medicine.