Over the last 10 years or so, infections caused by bacteria belonging to a particular branch of the genus Francisella have become increasingly recognised in farmed fish and molluscs worldwide. While the increasing incidence of diagnoses may in part be due to the development and widespread availability of molecular detection techniques, the domestication of new organisms has undoubtedly instigat...

Worldwide transfer and introduction of non-indigenous species in ballast water causes significant environmental and economic impact. One way to address this problem is to remove or inactivate organisms that are found in ballast water. In this study, 3 experiments were conducted in Puget Sound, Washington, USA, using a prototype ozone treatment system installed on a commercial oil tanker, the S/...

In this paper, we study the response of zebrafish to a robotic-fish whose morphology and colour pattern are inspired by zebrafish. Experiments are conducted in a three-chambered instrumented water tank where a robotic-fish is juxtaposed with an empty compartment, and the preference of live subjects is scored as the mean time spent in the vicinity of the tank's two lateral sides. The tail-beatin...

CURRENT SCIENCE, VOL. 90, NO. 8, 25 APRIL 2006 1130 *For correspondence. (e-mail: [email protected]) 8. Jhingran, V. G., Fish and Fisheries of India, Hindustan Publication Corporation (India), Delhi, 1991, pp. 541–593. 9. Le, Cren, L. D., Length–weight relationship and seasonal cycle in gonad weight and condition in perch Perca fluviatilus. Anim. Ecol., 1951, 20, 201–219. 10. Lazur, A. M., ...

Escape behaviors have been studied in zebrafish by neuroscientists seeking cellular-level descriptions of neural circuits but few studies have examined vertical swimming during escapes. We analyzed three-dimensional swimming paths of zebrafish larvae during visually-evoked and auditory-evoked escapes while the fish were in a cubical tank with equal vertical and lateral range. Visually evoked es...

Fish and other organisms are affected by pesticides which pollute the natural water through agricultural runoff. Fishes are common bioindicators of water pollution. In the present study bioassay of synthetic pesticide, Dichlorvos and a plant origin natural pesticide, Neem-On was separately done on Labeo rohita. Data obtained from the toxicity tests were evaluated using the Probit Analysis Stati...

Individual variation in the response to environmental challenges depends partly on innate reaction norms, partly on experience-based cognitive/emotional evaluations that individuals make of the situation. The goal of this study was to investigate whether pre-existing differences in behaviour predict the outcome of such assessment of environmental cues, using a conditioned place preference/avoid...

Hearing in fish has until a few years ago been considered to cover a sound frequency range from 20-30 Hz up to below 1000 Hz in most species. It is now known that the frequency spectrum extends down in the infrasound range (below 20 Hz). For cod, plaice, perch, roach, and salmon, hearing thresholds have been established by a conditioning technique for sound frequencies down to below 1 Hz. Tests...

Growth of Red, GIFT and Supreme Nile tilapia strains were evaluated. Fish were cultivated in indoor recirculation systems in 0.5 m3 tanks with controlled temperatures of 22, 28 and 30°C. Random samples of 20 fish from each strain (10 fish tank) were weighed at day 7, 30, 60, 90 and 120. Exponential model (y=Ae) and Gompertz model (y = Aexp(-Be)) were fitted and the estimates parameters were obt...