Aim and Objectives: Human continuously uses pesticides in the field to control pest population and weeds for considerable agricultural productivity. Side-by species like grazing-animals, insects and other species are adversely affected by or become resistant to pesticides. Insect, bird and cattle are highly abundant dwellers of the agriculture-field and represent three distinct phylum having versatile physiological features. Beside higher agricultural-productivity, protection to several species will maintain ecological/environmental balance. Studies on the effect of widely used pesticides on their DNA-stability and important enzymaticactivities are scanty. Materials and Methods: Antioxidant-activity (Superoxide-dismutase; SOD/Catalase- by gel-zymogram-assay) and DNA-stability (fragmentation-assay) in hepatic/gut tissues were studied here after in-vitro exposure of Chlorpyrifos, Fenvalerate, Nimbicidine or azadirachtin to goat/cow/poultry-hen/insect. Results: In general, all pesticides were found to impair enzymatic-activities. However, lower organisms are affected more than higher vertebrate by azadirachtin-treatment. DNA fragmentation was found more in insects/poultry-birds than that of the cattle in hepatic/gut tissues. Inversely, toxicity/antioxidant marker-enzymes were more responsive in insect gut-tissues. However, mitochondrial-toxicity revealed variable effects in different species. It is noticed, chlorpyrifos to be the most toxic pesticide followed by Fenvalarate/Nimbicidine (azadirachtin, AZT). Nevertheless, AZT revealed its higher DNA-destabilizing effects in the field-insects than the other animals. Conclusion: Field-insects are highly integrated to their ecosystem and the local bio-geochemical cycle, which may be impaired. Pesticides may have toxic effects on higher vertebrate and it may sustain in the soil after metabolized to its different derivative. Some of the sensitive biochemical parameters of this organism may be used as biomarker for pesticide toxicity.