الفهرس | Only 14 pages are availabe for public view |
Abstract Eggs of the intestinal parasitic helminthes Toxocara spp. are one of the most resistant pathogens to all ways of disinfection in water and waste water treatment plants. In this study inactivation of T. vitulorum eggs by ammonia and / or solar energy in laboratory conditions has been studied . T. vitulorum eggs were used as an alternative model for A. lumbricoides. The effects of ammonia different concentration, solar energy, pH, and temperature on Toxocara eggs viability and vitality were studied. Eggs in water samples with ammonia different concentration (0%, 1%, and 2% ammonia) that were placed in duplicates and pH values were measured. The results suggested that the presence of ammonia at 2% concentration encountered allowed for 70% inactivation of T.vitulorum eggs. The applicability of solar energy for disinfection of T.vitulorum eggs using one-side blackened PET bottles were continuously exposed to direct sun light for seven hours which maintained water temperature in the range of 50 – 55 °C that was enough for destroying 85 % of T. vitulorum eggs. Complete destruction of the eggs (100%) was achieved at 65.5°C with an ambient temperature of 40 °C. The influence of solar energy against the viability of Toxocara eggs in water using a 4’, 6- Diamidino-2-Phenylindole (DAPI) and Propidium Iodide (PI) vital stains was found to be highly significant (P < 0.001). The effect of ammonia , pH , solar energy and combination of ammonia (2%) and solar energy on samples containing T.vitulorum eggs with temperature values ranging from 25°C to 55°C with 21 days of storage with low moisture content (30%) were measured . Summary - 7 9 - Moreover viability of eggs using fluorescent microscope and scanning electron microscope techniques, (DAPI); and Propidium Iodide ( PI) as a vital stain were evaluated. The results showed that 100 % inactivation of T. vitulorum eggs that could be possible in samples. All of these results were approved and supported by using ELISA technique that indicated that antibodies level appeared and increased at positive control group of experimental animals . Also using ultrasonography technique indicated that there is a clear morphological changes and lesions appear in liver surface in positive control group ,while in treated groups with ammonia (2%) and solar energy no morphological changes or any lesions appear at ultrasound because no infection occur as the eggs were damaged by the effect of combination of ammonia (2%) with solar energy. Supporting that these results have an important implication for ecological sanitation and sustainable development technologies in water and waste water treatment plants in Egypt and other countries . The low cost and operational simplicity of this study make it affordable , usable and applicable in fields of water and wastewater treatment plants with biological sustainable disinfection of parasites. It is more useful in rural areas where other sources of energy like electricity and gas are not easily available. |