ACUTE-INFLAMMATION IN FETAL AND ADULT SHEEP - THE RESPONSE TO SUBCUTANEOUS INJECTION OF TURPENTINE AND CARRAGEENAN

Because of the small number of inflammatory cells found in skin wounds , it has been considered that foetal sheep are incapable of an adequat e inflammatory response. The present study shows that subcutaneous inj ection of turpentine or carrageenan into foetal sheep consistently exc ites a severe cellular inflammatory reaction. At 75 days gestation the inflammatory cells are all macrophages. As the foetus develops, polym orphs play an increasing role in the early response to turpentine. By 120 days inflammatory cells are almost all polymorphs as in adult shee p. However the response to carrageenan remains macrophage in type. At all stages of gestation the acute cellular response is followed by dev elopment of scar tissue, more pronounced with turpentine than carragee nan. Any proposed intrauterine surgery must allow for the pronounced a nd prolonged inflammatory response and scar tissue formation caused by persistent inflammatory stimuli in foetal animals.