Toxicological Impact of Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on Some Hormonal Profiles and Hematological Parameters in Goats

Abstract

Female Baladi goats were used to investigate the toxicological effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on some serum hormones and blood features. Animals were divided into two groups, group 1: served as control, group 2: animals were orally administered with three repeated doses (0.23µg/Kg body weight) of TCDD with 2 days interval between dosing. Results revealed that exposure to TCDD induced reduction in serum estradiol, progesterone and prolactin levels and elevation in glucocorticoid hormone cortisol throughout the different studied periods (48h, 96h and 16 days commenced the last intoxicated dose). The adverse impact of TCDD on goat reproductive hormones was confirmed by histopatholgical observations on their uteri and ovaries after 16 days commenced the last intoxicated dose. Intoxication of goats with TCDD showed also marked decreases in hemoglobin (Hb) concentration, red blood cell count (RBC), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentrations (MCHC) compared with normal healthy group. Pronounced decreases in total white blood cells (WBC) count as well as in its differential percentages namely lymphocytes, monocytes and eosinophils were also noticed in intoxicated animals compared with normal ones, while the percentage of neutrophils showed significant increase. In conclusion, the results of this study indicated that oral exposure of female goats to repeated doses of TCDD caused endocrine disruption which may lead to adverse impact on their reproductive performance. Moreover, toxicity of TCDD induced immunosuppressive effect and anemia as indicated by its deleterious action on different hematological parameters.