Sayda Hafez

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Acute lethal toxicity of Cyanobacteria (blue-green algae) was investigated against 3rd larval stages of Musca domestica, and Culex pipiens, and 4th larval stages of Spodoptera littoralis and Agrotis ipsilon. The LD50s were 1.94, 2.33, 7.59 and 9.10 microg for M. domestica, C. pipiens, S. littoralis and A. ipsilon respectively. The slope functions were 4,045(More)
In order to measure the digestibility of feed with an indicator method two trials were realized on the dairy research farm "Karkendamm". The first trial was to test the suitability of TiO2 as an indicator to determine the digestibility in cows. The rate of recovery of the indicator was 98.8% (95.5%-101.9%). The concentration of TiO2 of the rectal samples in(More)
Five doses (1, 0.5, 0.25, 0.125 and 0.0625) of the chitin inhibitor BaySir-8514, and anti-juvenoid precocene II were topically applied to the third larval instar of the grey flesh fly Parasarcophaga dux. Toxicity of both compounds were recorded against different developmental stages at the different dose levels. The lowest dose (0.0625) of both compounds(More)
Introduction: Blood alterations in fish or damage of hemopoietic tissue organs may be associated either with changes in environmental conditions or with water born pollutants (McCay, 1929, Dawson, 1935 & Gradner and Yevich 1969b). Most of the previous studies on the effect of intoxication with pollutants on blood characteristics, were based on differential(More)
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