To determine morphology after administration of tetracycline and zinc chloride in adult albino rats and prenatal conceptus.

Introduction: Administration of tetracycline therapy is controversial during growing age as stated by earlier workers. However the effect of simultaneous administration of tetracycline & Zncl2 on pre-natal concepts has remained undocumented.Objective: To compare the effect on conceptus after maternal ingestion of tetracy-cline and Zncl2 by prospective experimental animal study model using adult albino rats.Methodology: Tetracycline & ZnCl2 was administrated to pregnant female albino rats two times therapeutic dose for 10 days. (from day 8 to day 18 of pregnancy.) Each animal was weighted on day 1, day 8 & day 18 of pregnancy. Abortion resulted on day 18th of pregnancy. Each group of pregnant animal were scarified on day 18 of gestation by overdose of either anesthesia, abdomen opened, uterus & both cornu containing conceptus identified, removed, there weight recorded, crown rump length was measured & was compared with similar value of control animals. The results were statistically analyzed to find out the significance.Result: Maternal administration of tetracycline decreased maternal bodyweight to 38.4 ±0.9gm. However simultaneous administration of ZnCl2 maintained body-weights to 41.4 ±0.7gm. The body weight and crown rump length (CR Length) in conceptus decreased by 4.52 ±0.10gm and 3.06 ±0.09 cm respectively. That tetracy-cline & ZnCl2 administration maintained the body weight & CR length by 5.46 ±0.09 gm and 3.79 ±0.13gm respectively.Conclusion: Pre-natal administration of Tetracycline alone cause reduction in ma-ternal body weight as well as reduction in body weight & CR length of rat conceptus. However simultaneous Zncl2 maintain body weight & CR length leading to growth of the rat conceptus.Keywords: Tetracycline, ZnCl2, Rat Conceptus. Crown Rump Length (CR Length).