Histopathology provides a rapid method to detect effects of irritants and pathogens in different organs and it can be considered as the indicator for abnormal condition for fish environment. The present study was initiated to record the histopathological lesions of gill and skin associated with external parasites in two common aquarium fish, Oscar (Astronotus ocellatus) and Discus (Symphysodon ...

The aerobic granular sludge (AGS) process is an effective wastewater treatment technology for organic matter and nutrient removal that has been introduced in the market rapidly. Until now, limited information available on AGS regarding of bacterial viral pathogenic organisms present sewage. This study focussed determining relation between reactor operational conditions (plug flow feeding, turbu...

the astacus leptodactylus specimens were collected from four sites of aras reservoir, north-west of iran and examined for the epibionts during 2009. protozoan epibionts from ciliophora (one genus and seven species) and tracheophyta were isolated from the cuticular surface of different body parts of narrow-claw crayfish, a.leptodactylus. seasonal prevalence of infestation was determined in 394 i...

Surviving predation is a fitness trait of Escherichia coli O157:H7 (EcO157) that provides ample time for the pathogen to be transported from reservoirs (e.g. dairies and feedlots) to farm produce grown in proximity. Ionophore dietary supplements that inhibit rumen protozoa may provide such a selective advantage for EcO157 to proliferate in lagoons as the pathogen is released along with the undi...

Studies of contractile responses and their control by electroionic mechanisms have been performed primarily on vertebrate muscle (Huxley & Taylor, 1958; Hodgkin & Horowicz, 1960; Sandow, Taylor & Preiser, 1965); however, mechanical responses correlated with bioelectric potentials also occur in a number of other cells in both the animal and plant (Sibaoka, 1966) kingdoms. The Protozoa, especiall...