Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Turpentine-induced skin reactions in young Alligator mississippiensis kept at 25(DEGREES)C were employed to study reptile inflammatory response. Skin lesions, harvested at intervals from 4 hours to 30 days post-inoculation exhibited no gross changes until day 24-26, when superficial skin necrosis and sloughing occurred. Early responses of congestion and dermal edema (4-8 hours) were seen by light microscopy, followed by necrosis and granulocyte migration (1-3 days). There was later predominance of monocytic cells, including vacuolated macrophages (7 days - 30 days). At 30 days post-inoculation, central dermal zones of necrotic debris were surrounded by palisades of vacuolated multinucleated giant cells and capillary-laden immature fibrous connective tissue. Systemic illnes or viseral lesions were not observed. Controls received inoculations of sterile saline solution and had no gross, microscopic or hematological changes. Hematologic studies were performed to establish control values and evaluate effects of turpentine. Thirty-five control animals showed mean total leukocyte counts of 6.4 x 10('3)/mm('3). Leukocyte types were identified by light microscopy, and subsequent mean differential values were 50.0% heterophils, 10.0% eosinophils, 14.0% basophils, 25.0% lymphocytes, 1.0% monocytes. Mean total thrombocyte counts were 22.5 x 10('3)/mm('3). Treated animals had significantly increased heterophil percentages (60%). Normal buffy coat leukocytes were characterized by transmission electron microscopy. Heterophils had elliptical granules of variable electron density. Eosinophils had oval electron-dense granules lacking crystalloid cores. Basophils, lymphocytes and monocytes resembled their mammalian counterparts. Thrombocytes resembled their avian counterparts. Positive histochemical tests were as follows: chloroacetate esterase-lymphocytes and monocytes; non-specific esterase-heterophils, lymphocytes and monocytes; peroxidase (weak) - heterophils and eosinophils; acid phosphatase - heterophils, basophils and monocytes; alkaline phosphatase - heterophils, eosinophils and monocytes. Phagocytosis and killing were performed by adding live Staphylococcus aureus to whole blood (anticoagulated). Staining with acridine orange and observation with fluorescence microscopy showed phagocytic and weak killing ability for monocytes, heterophils and to a lesser degree eosinophils.