The use of steroid-treated feeds as 17 a-methyltestosterone for the production of all-male populations is widespread in tilapia aquaculture. The aim of the present study was to investigate the misuse effects of methyltestosterone on monosex farmed Nile tilapia, Oreochromis niloticus by evaluation of hematological and biochemical values. The fishes were obtained from four localities (Assiut as a control, Beheira, Alexandria and Kafr el-Sheikh: three farms from each governorate as farmed monosex produced using methyltestosterone). The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), white blood cell count, blood platelets, lymphocyte, monocyte, neutrophils and basophils were determined. The results showed that there were changes in the erythrocytic series and in the defense white blood cells. Activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP), glucose, cholesterol, total protein, uric acid and creatinine were determined for biochemical study. These alterations are considered an indication for performance and health of fish in the monosex culture medium indicating the side effects of overdose induction of MT.

From a previous study we have determined that commercial security products can suffer from a usability perspective, lacking the necessary attention to design in relation to their alert interfaces. The aim of the paper is to assess the usability of alerts in some of the leading Internet security packages, based upon a related set of usability criteria. The findings reveal that the interface design combined with the user’s relative lack of security knowledge are two major challenges that influence their decision making process. The analysis of the alert designs showed that four of the criteria are not addressed in any of the selected security measures and it would be desirable to consider the user’s previous decisions on similar alerts, and modify alerts according to the user’s previous behaviour.