الفهرس 
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Abstract
Pharmaceuticals are synthetic compounds that have significant biological activity with particular mode of action to living cells. Many of veterinary antibiotics (VA) are poorly absorbed in the animal gut, so the most of administered dose is excreted through feces. A considerable amount of animal manure is frequently used as fertilizer as it is rich in nutrients and organic matter, but it also has elevated concentrations of antibiotics. Such compounds might be toxic or cause allergies to humans, thus their presence in food is undesirable. E.g. Oxytetracycline (OTC) is a member of Tetracyclines (TCS) and axis of the present study. It is widely used as veterinary drug and feed additive.
Investigating the concentration of VPs in manure is common, due to their potential risk for environment, microorganisms, as well as human health. Another serious issue is related to heavy metals that are described as one of the most dangerous groups of environmental contaminants.
Earthworms are often preferred subject in soil ecotoxicological research because they are quite easy to handle and measure their different life cycle parameters. Exposing the earthworms to pollutants, their antioxidant system will have response immediately. Consequently, earthworms are widely used to monitor various pollutants as a sensitive bio-indicator.
The present study utilized earthworm as biomarker to achieve or realize the toxicity level in the soil by examining the total proteins, superoxide dismutase (SOD), nitric oxide (NO), catalase (CAT) and the rate of lipid peroxidation (LPO) of A. longa samples collected from citrus orchard in Shandweil island, Sohag governorate.
The present study aimed to make a survey of earthworms inhabiting in Shandwil Island (Sohag Governorate) and detect the dominant species, measure of some ecological factors (soil and air temperature, pH, soil water content and organic matter), OTC and heavy metals ”Fe, Cu, Zn” in different sites at the investigated area, estimate common earthworm density and biomass in different sites at the investigated area, examine the effect of different environmental factors (ecological factors, OTC and heavy metals ”Fe, Cu and Zn”) on the common earthworm density and biomass, measure the OTC and heavy metals bioaccumulation in dominant species of earthworm, study the effect of OTC and investigated heavy metals ” Fe, Cu and Zn” on oxidative stress parameters on the dominant species
To achieve these targets, two trips to the field were done to collect the earthworm samples. Samples collected in the first trip (through two tours) were used to identify the species and study their community structure. While in the second trip, samples of the dominant species only were collected to study the ecological and biochemical effect of oxytetracycline (OTC) and heavy metal on it as well as on soil, litter.
The present study revealed the following results:
Six species were recorded from fifty different points; these six species belong to 4 genera to 2 families (Lumbricidae and Megascolecidae). These species are Aporrectodea trapezoids, Aporrectodea caliginosa, Aporrectodea longa, Octolasion cyaneum, Lumbricus rubellus, Amynthas cortics. The composition of earthworms community at this area ranged between 3 to 5 species. The dominant species was Aporrectodea longa. The measured ecological factors, air and soil temperature, soil water content had highly significant difference with earthworm densities and biomass.
The present results indicated that the order of OTC concentration was, A. longa > litter > soil. The reason is due to the direct contact of soil to air which causes the decomposition of OTC, while for OTC in litter, the photolysis process may also lead to the decomposition of OTC. The order of heavy metals, Fe concentration was, soil > A. longa > litter. Cu concentration was, soil > litter > A. longa, while Zn concentration was, A. longa > soil > litter.
Biomagnification (BMF) and bioconcentration (BCF) factors of OTC were 6.76 and 32.86, respectively. However, BMF and BCF of studies metals were relatively less than OTC and decreased in the following sequence Cu < Fe < Zn.
Oxidative stress results showed that there was high significant correlation between both catalase and lipid peroxidation with air temperature. The non-significant correlation between other parameters might be due to the low concentration of OTC, Fe, Cu and Zn.
The conclusion of the present work can be summarized in the following points:
-Six species were recorded; Aporrectodea longa (the dominant species), and Amynthas corticis “snake worm” was accidental species and the first time recorded in Sohag governorate.
-Air and soil temperature factors had highly significant negative effect on earthworms. Soil water content had positive effect on distribution of earthworms species. Organic matter and pH factors had non significant, organic matter values (7:9) %, pH values (8:8.4).
-OTC concentration was ordered as, A. longa > litter > soil . Fe concentration was, soil > A. longa > litter, Cu concentration was, soil > litter > A. longa, Zn concentration was, A. longa > soil > litter.
-Biomagnification (BMF) and bioconcentration (BCF) factors of OTC were 6.76 and 32.86, respectively as OTC accumulates in A. longa.
Recommendation
-Pollutants monitoring should be done systematically, using laboratory experiments especially for pharmaceutical residues.
-Manure should be pre-treated before using as fertilizers.
-Utilizing the earthworms to connect the environmental and biochemical impact of pollutant.s.