International Journal of Aquatic Biology
Volume:2 Issue: 3, Jun 2014

Schismatogobius deraniyagalai is recorded from the Seethanathi River of Karnataka state in the southern part of India. Previous records of these species were from the streams in Kerala of India and from freshwater habitats of Sri Lanka. Herein we report the occurrence of this species in Seethanathi River showing its distribution extended further north along the west coast of Peninsular India.

The sexual maturation and spawning period of blood cockle in Matang mangrove estuary was studied by naked eye and histological observations of the gonads from July 2010 to April 2011. The high spawning period was from November to February. However, at one station where bottom sediment exhibited a severe reduction in potential of −100 mV lower, immature individuals were common. These results suggest the redacting environment inhibits the sexual maturation of blood cockle.

Effects of ambient copper was investigated on serum stress markers, sodium and enzyme levels in Common carp (Cyprinus carpio L.) over a 14-d exposure period. Fish were exposed to 0, 25 and 100 μg L-1 copper (as copper sulfate) and blood was sampled at 0, 3, 7 and 14 d after exposure. Serum profile was significantly affected by copper concentration, sampling time and their interaction. Increase in serum levels of cortisol, glucose, alanine aminotransferase and aspartate aminotransferase and decrease in serum sodium levels were observed in both copper-exposed groups, 3 d after copper exposure, which lasted until the end of the experiment. It is concluded that copper exposure causes stress response and sodium loss in common carp. Likewise alanine aminotransferase and aspartate aminotransferase increase after exposure which might be as results of either tissue damage or stress.

Copper is most toxic metal in marine organisms. Characterization of protein occurring in the metabolically active tissues of muscle (MU), hepatopancreas (HP) and gills (GL) of the spiny lobster, Panulirus homarus homarus on exposure to two sub-lethal doses (9.55 and 19.1 µg/l) of copper were studied for 28 days of exposure (DoE). The electrophoretic pattern of muscle, hepatopancreas and gill proteins revealed 12, 8 and 8 slow moving bands (control). The number of bands decreased to 8 and 7, 6 and 5, 6 and 4 after 7 days of exposure to 9.55 µg/l and 19.1 µg/l concentrations of copper, respectively. After 28 days, the protein bands decreased to 7 and 6, 5 and 4, 4 and 4 at 9.55 µg/l and 19.1 µg/l concentrations of copper, respectively. Present study to indicate that to avoid the Cupro-Nickel coil in lobster holding centers in chiller plants used for cooling of water was found to be responsible for the mortality of lobsters during live transportation.

The present study investigates the effects of water temperature on digestive enzymes activity and food transit time in Caspian kutum (Rutilus kutum) larvae. Caspian kutum larvae (532 ± 0.05 and 543 ± 0.02 mg) were divided into two groups with three replicates and reared at different water temperature i.e. 25.6 ± 0.4°C (T1) and 18.4 ± 0.1°C (T2). At the end of the experiment, sampling of intestine was performed at 0, 1, 3, 5, 8, 16, 24 and 30 h after feeding from each treatment. In T2, food was observed until 24 h after feeding and the intestine was empty 29 h after feeding, while in T1 19 h after feeding the intestine was empty. Digestive enzymes activities were higher in T2 treatment. The peaks of trypsin and alkaline phosphatase enzymes activity were found 8 h after feeding in T1, while occurred 16 h after feeding in T2. The highest chymotrypsin and alpha-amylase enzymes activity were observed 5 and 8h after feeding in T1 and T2, respectively. These results confirmed remarkable effects of temperature on food transit time and digestive enzymes activity of Caspian kutum.

The cellular organization of the olfactory epithelium of Puntius sarana (Hamilton, 1822) was explored by means of optical and scanning electron microscopy. The oval shaped olfactory rosette was composed of 26-28 primary lamellae distributed from both sides of the central raphe. The sensory epithelium confined chiefly on the linguiform processes of the lamella and rest of the portion consisted of non-sensory epithelium. The sensory epithelium was embossed with morphologically distinct three types of sensory cells: ciliated, rod and microvillus receptor cells. The non-sensory epithelium was made up of mainly stratified epithelial cells and mucous cells. Different cells lining the olfactory epithelium were discussed in relation to mode of life and living of the fish concerned.

The acute toxicity of salts of alkali and alkaline earth metals, such as sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) were studied on the egg and larval stages of Indian major carp Labeo rohita (Hamilton). The acute toxicity experiments were conducted followed by the range finding bioassay tests. The experiments were conducted in triplicates. The cumulative percentage of dead or damaged eggs at the end of 6, 12, 18, 24, 36, 48, 60, 72 and 96 hours was recorded for the calculation of LC50. The increase in salt concentrations in water increased their toxicity and reduced the duration to damage 50% of the eggs. The eggs became smaller than their normal size and whitish before being damaged in the test solutions. Most of the exposed eggs and hatchlings tended to lay on the floor of the tank. The toxicity of the metals was in the order of K>Na>Mg>Ca. The 96 hours LC50 values were 3.25, 2.73, 28.9 and 20.52 ppm for sodium, potassium, calcium and magnesium, respectively.

Study of phenotypic diversity among populations can help better understanding of diversification of species within ecosystems and intraspecific diversification in fishes. A geometric morphometric study was carried out using the Elliptic Fourier analysis to demonstrate the effect of habitat type on morphological features of shemaya (Alburnus chalcoides) populations. Populations were sampled from three rivers and one lagoon, from the southern part of Caspian Sea. Significant differences in body shape were found among the populations. Differences in shapes of the riverine populations were minute compared to those of lagoon one in terms of size and shape. Shemaya is an anaderemus fish and its populations have a common origin, therefore, observed differences could be as result of environmental factors. In addition, this study suggest that the amount of curvature i.e. fusiform body shape of this species could be independent form environmental condition.