Acute Toxicity of Urea Fertilizer to Tilapia zilli Fingerlings

The fingerlings of Tilapia zilli (mean weight 7.95 ± 0.33g) were exposed in glass aquaria to acute concentration of urea fertilizer for a period of 96 hours. The 96hr LC50 of the exposed fish was determined to be 15.85 gl-1 with lower and upper confidence limits being 8.85 and 28.46 gl-1 respectively. During the exposure period, the fish stood in upright position with their snouts above the water surface gasping for air. Other behavioural reactions of the exposed fish observed before death were uncoordinated swimming, restlessness, frequent attempts at jumping out of the tank and quietness. Water quality examination showed a decrease in the dissolved oxygen content and increase in total dissolved solute, conductivity, alkalinity and free carbon dioxide as the concentration of the fertilizer was increased. The toxicological implications of these findings in relation to environmental pollution are discussed. Keywords:Urea fertilizer, Acute toxicity, Tilapia zilli Bio-Research Vol. 6 (1) 2008: pp. 298-30

Fenthion induced toxicity and histopathological changes in gill tissue of freshwater African catfish, Clarias gariepinus (Burchell, 1822)

Fenthion is an organophosphate pesticide commonly used in agriculture and public health for the control of insect pests. The present study investigated the toxic effect of fenthion and the histopathological alterations in the gill tissue of African catfish Clarias gariepinus. The 96 h LC50 value of fenthion in C. gariepinus determined by probit analysis was found to be 39.97 mg/L. Fish exposed to different fenthion concentrations showed clinical signs such as erratic swimming, attempt to jump out of water, increased opercula frequencies, air gasping, mucus secretion followed by exhaustion and death. To evaluate the histopathological changes in the gill tissue, fish were exposed to 2.0, 4.0 and 8.0 mg/L corresponding to 1/20, 1/10 and 1/5th, respectively of 96 h LC50 of fenthion for 21 days and 7 days recovery. Gill disorder and fusion of the secondary lamellar were pronounced in all treatments. Alterations in gill structure exposed to the highest concentration were oedema, lifting of lamellar epithelia, destruction of gill architecture and lamellar fusion. From the findings, it can be deduced that fenthion-induced alterations are irreversible and therefore should be applied with caution in the environment so as to reduce its damage to aquatic organisms.Keywords: Clarias gariepinus, fenthion, lethal concentration, histopathology

Glyphosate does not substitute for glycine in proteins of actively dividing mammalian cells

Glyphosate (N-phosphonomethyl glycine) and its commercial herbicide formulations have been shown to exert toxicity via various mechanisms. It has been asserted that glyphosate substitutes for glycine in polypeptide chains leading to protein misfolding and toxicity. However, as no direct evidence exists for glycine to glyphosate substitution in proteins, including in mammalian organisms, we tested this claim by conducting a proteomics analysis of MDA-MB-231 human breast cancer cells grown in the presence of 100 mg/L glyphosate for 6 days. Protein extracts from three treated and three untreated cell cultures were analysed as one TMT-6plex labelled sample, to highlight a specific pattern (+/+/+/−/−/−) of reporter intensities for peptides bearing true glyphosate treatment induced-post translational modifications as well as allowing an investigation of the total proteome

Stability of Serum/Plasma Glucose for the Diagnosis of Diabetes Mellitus

Due to inconsistent power supply in the developing countries, particularly in the rural areas, immediate sample separation and analysis may not be practicable. This study investigated the time-related changes in glucose concentration of serum and plasma specimens stored at 4oC and room temperature (32oC) for 3 days. Blood samples were collected from 30 fasting patients suffering from diabetes mellitus at the Ebonyi State University Teaching Hospital (EBSUTH), Abakaliki, Nigeria. Glucose levels were assayed using glucose oxidase method immediately upon sample collection and separation to obtain the baseline value (BV) and thereafter at specified time intervals across 72 hours. In serum samples, the values obtained after 2 hours at 32oC and at the 72nd hour at 4oC were significantly different (

Food and Feeding Habits of Distichodus Species (Osteichthyes: Distichodontidae) in Anambra River Basin, Nigeria

The food and feeding habits of Distichodus rostratus, D. brevipinnis and D. engycephalus in Anambra river were studied over a period of 12 months. The stomach contents of 499 specimens were analysed using percentage number (%N) and percentage relative frequency (%RF) methods. The three species are omnivorous bottom and surface water feeders, feeding more on plant materials (seeds, fruits, grasses and filamentous green algae) than on food of animal origin (ants, insects and fish). The stomach fullness analysis showed that 57.3 ± 2.9% (53.8 – 59.5%) of the stomachs examined had food while 42.8 ± 2.9 % (40.8 – 46.2%) were empty. The species fed on the same kinds of food items in slightly varying degrees of % N and % RF. Raabe's coefficient factor (R = 81.0%, %RF; 60.7%, %N) indicated a high degree of similarity in the food preference of the species. The percentage full stomach and partially full stomachs were significantly higher in the rainy season than in the dry season (

Morphometric Variations Among Three Distichodus Species Of Anambra River, Nigeria

No Abstract. Animal Research International Vol. 2 (3) 2005 pp. 372-37