Some aspects of experimental culture of the oyster Crassostrea madrasensis(Preston)

Settlement and rate of growth of the oyster Crassostrea madrasensis (Prastcm) wwe studied at the Mulki Estuary, Dakshina Kannada. The breeding season extends from October to May. Peak Settlement of spat takes place during November-December and March-April. Of the several cultch materials tried, oyster shell, used automobile tyres, rigid PVC, lime-coated tiles and asbestos were found to be suitable. Cultch smeared with crude extracts of oyster tissiM supported more spat per unit area than the untreated panels. Tliespjt grew initially at the rate of 2-3 cm per month. Spat transferaed to suspmded wire bag grew faster than the feral ones. The oysters attained^ 7.0 cm shell-height in about 7 months. The size at fiiBt maturity was 12-14 mm for males and 24-26 mm for females^ Study of 4he condition and edibility indicies showed that die best season for harvest is May-September

Feeding habits of the Pearl-Spot Etroplus suratensis (Bloch) in the Nethravati - Gurpur estuary

Occurrence of decayed organic matter in the stomach showed seasonal variations which were related to relative abundance of food, selectivity, age and diurnal variations in feeding. Filamentous algae Spirogyra fonned an important item of the diet in November. A change in diet with increase in size of fish was noticed. While fish of 8 em T L preferred decayed organic matter and microvegetation, larger fish fed on a variety of food. Increased occurrence of sand grains in larger fish suggests habitual bottom feeding. Intensive feeding was noticed in early mature and spent fish. Feeding intensity appears to be related to spawning activity, besides food abundance

Reproduction of the Pearl-Spot, Etroplus suratensis (Bloch) in the Nethravati - Gurpur Estuary, Mangalore

Spawning of Etroplus suratensis in the Nethravati•Gurpur estuary took place from August to November and January to February with peak activity during August. The male: female ratio was 1 : 2.73, indicating a significant dominance of females in the population. Up to size group 18 - 19 em T L., the females dominated. In the larger individuals there was no significant difference in the ratio

Growth, condition and sexuality of the Indian sandwhiting, Sillago sihama (Forskal)

In the sandwhiting Sillago sihama (Forskal) inhabiting the coastal and estuarine waters of Mangalore region the value of the equilibrium constant a was 2.9554 indicating isometry in the relation between fish length and body weight. Condition in ooth sexes was highest in June and related to gonadal maturit

Instance of unusual feeding behaviour of the Indian mackerel, Rastrelliger kanagurta (Cuvier) off Mangalore

Swarms of Acetes are known to occur in the inshore waters and ascend up the estuaries in this region during this time of the year. The senior author found Acetes to be an important item of food of other fishes also like Lactarius lactarius and Trichiurus lepturus at the same time in tms area. Occurrence of immature individuals of L. lactarius (35 to 112 mm total length) in large numbers in the inshore waters off Mangalor

Account of the Flatfishes of the Mangalore Coast and Notes on their Fishery

12 specimens were studied for morphological and meristic characters. Most characters agreed with earlier descriptions. Dorsal and anal fins were tipped white unlike black as reported by Fischer and Bianchi (1984). Maximum length recorded was 540 mm

Estuarine Clam Resources of Dakshina Kannada District

The estuarine clam resources of Netravathi-Gurupur, Mulki, Udayavara and Coondapur estuaries were estimated based on a study on the distributin of clams in space and time. T he three commercially important species were Meretrix meretrix, M. casta, and Katelysia opima

Biotic potential and environmental resistance of bivalves of Mangalore coast

Biotic potential and environmental resistance of seven sgecles of bivalves inhabiting Mangalore coast have been quantified from data gathered during the past 15 years. The species examined are the oysters Crassostrea madrasensis (Preston), Saccostrea cucullata (Von Born), the clams Meretrix casta (Hanley), Katelysia opima (Gmelin) Villorita cyprinoides (Gray), Donax incarnatus (Gmelin) and the mussel Perna viridis (Linnaeus) Components of blotic potential are described in terms of distribution and density, growth survival, longevity, age, size at first maturity and production. Environmental resistance was delineated by examining spawning', settlement, survival crowding, overgrowth, fouling and mortality. Data on these aspects have been presented and discussed

Influence of drug susceptibility on treatment outcome and susceptibility profile of 'failures' to category II regimen

Objective: To assess the influence of drug resistance on treatment outcome among patients treated with Category-II regimen and document drug susceptibility pattern of “Failures” to this regimen. Design: A retrospective analysis of patients registered from May 1999 through December 2004. Results: Treatment success was 42% among 572 patients and was similar among patients with fully susceptible or resistant but non-MDR organisms (41% of 254 and 40% of 128 patients, respectively). Among 49 MDR-TB patients, 27% had successful treatment outcome. The failure rates among patients with fully susceptible, resistant but non-MDR and MDR bacilli, were 6%, 12% and 27% respectively. Default was significantly higher among males (53% vs. 34%: p<0.01) smokers (57% vs. 36%: p <0.001), alcoholics (58% vs. 39%: p <0.001) and patients with higher initial smear grading (2+ or 3+, 56% vs. scanty or 1+, 44%: p <0.01). DST results were available for 60% (31 of 52) of failures and 10 had MDR-TB. Conclusion: The low success rate to the re-treatment regimen was mainly due to non-compliance. Failure was observed among 9% of patients and MDR-TB was 32% among Category II failures. The currently recommended Category II regimen appears to be adequate for majority of re-treatment cases

Temporal variability of phytoplankters in Vellar Estuary

63-69Seasonal variation in the numerical abundance of 42 spp of phytoplankters (18 centric, 20 pennate diatoms, 3 dinoflagellates and 1 Trichodesmium) at the mouth of the Vellar Estuary, Tamil Nadu, India has been followed for 3 yr. Quantitative distribution of diatoms follows trimodal annual patterns. Negative correlations exist between diatom density and blooms of dinoflagellates and Trichodesmium. Variations in quantity and settling volume correspond to changes in ambient salinity. Shannon-Wiener indices are linearly related to number of species, phytoplankton density and settling volume. Temporal variations in the community largely depend on the salinity and to a lesser extent on the ambient surface water temperature. The correlation matrix reveals the presence of atleast 5 diverse components in the phytoplankton community