Aim: Tulathromycin is used as extralabel in sheep, whereas there has no any data about safety in sheep. The aim of this research was to determine the safety of tulathromycin in sheep.

Materials and Methods: In this research, single dose of 2.5 mg/kg tulathromycin was administered subcutaneously to 10 male yearling sheep. Blood samples were obtained before (0. day, control) and after at 0.25, 0.5, 1, 2, 3, 4, 5, 6, 7, 8 and 9 days. Serum cardiac (Troponin I, creatin kinase-MB mass), hepatic (Alkaline phosphatase, total bilirubin, alanine aminotransfrerase, aspartate aminotransferase, gamma glutamyltransferase, total protein, albumin) and renal (Blood urea nitrogen, creatinine) damage markers were determined while hemogram values (White blood cell, red blood cell, platelet, hemoglobin, hematocrit) were measured from blood samples.

Results: There were no any clinical changes observed in sheep during experimental period. Increased troponin I level was determined (P<0.05) at 1st day, while statistically significance changes (P<0.05) were determined within reference range in hepatic (Total bilirubin, alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase, total protein, albumin) and renal (Blood urea nitrogen, creatinine) damage markers when comparet to Control (0 day). In addition, decreased red blood cell counts, hemoglobin and hematocrit levels were measured (P<0.05) at 6th day.

Conclusion: Tulatromycin may cause transient increase in the cardiac damage markers and changes in the blood picture. However, it is stated that single dose (2.5 mg/kg, SC) of tulatromisin may safe in sheep.