Jayasree Loka | Central Marine Fisheries Research Institute, Cochin (original) (raw)

Papers by Jayasree Loka

Research paper thumbnail of Loose shell syndrome (LSS) of cultured Penaeus monodon - microbiological and histopathological investigations

Indian Journal of Fisheries, 2012

Investigations were undertaken on loose shell syndrome (LSS) of cultured Penaeus monodon during t... more Investigations were undertaken on loose shell syndrome (LSS) of cultured Penaeus monodon during the period 2009 - 2010. The infected shrimps were collected from culture ponds of east and west Godavari districts in Andhra Pradesh, India and were subjected to microbiological and histopathological studies. Four species of Vibrio were isolated from the diseased shrimps and were identified as V. harveyi, V. alginolyticus, V. metschnikovii and V. fluvialis based on morphological characteristics and biochemical tests. Histopathological studies revealed the presence of occlusion and inclusion bodies of monodon baculovirus (MBV), hepatopancreatic parvo-like virus (HPV), and white spot syndrome virus (WSSV) in hepatopancreatic and gill tissues. All the LSS affected shrimps collected during the present study were found infected with V. harveyi and concurrent infections of other Vibrio species were observed in 40% of the samples. Prevalence of infection with WSSV, MBV and HPV was less compared ...

Research paper thumbnail of Broodstock development, breeding and larval rearing of Acanthopagrus berda (Forsskal, 1775), a suitable species for farming in tropical waters

Research paper thumbnail of Standardization of culture aspects of Apocyclops cmfri sp. nov. a nativecyclopoid copepod

Copepods are considered as ideal larval feed, due to their smaller size (<100μm), high protein... more Copepods are considered as ideal larval feed, due to their smaller size (<100μm), high protein and favourable fatty acid profiles. There are three types of copepods viz., harpacticoid, calanoid and cyclopoid, which can be cultured on a large scale under controlled conditions as live feed for the initial stages of fish and shellfish larvae. Karwar Research Centre of ICAR- CMFRI made a significant contribution in standardizing the protocols for the culture of a new cyclopoid copepod,

Research paper thumbnail of Apocyclops cmfri sp. nov. (Cyclopoda : Cyclopoida : Cyclopidae), a new copepod species from marine waters of Karwar, Karnataka, India

Indian Journal of Fisheries

A new species of Apocyclops Lindberg (Cyclopoda: Cyclopoida: Cyclopidae) is described based on sp... more A new species of Apocyclops Lindberg (Cyclopoda: Cyclopoida: Cyclopidae) is described based on specimens collected from marine waters of Karwar, Karnataka, India. At present, there are 11 valid and accepted species excluding one extinct species (fossil) in this genus which are widely distributed in fresh and brackishwater areas in the tropics and subtropics. Five valid species of Apocyclops are reported from the Asian region, including two species from India. The new species is closer to the previously reported Indian species, A. royi (Lindberg) and A. dengizicus dengizicus (Lepeshkin). Apocyclops cmfri sp. nov. differs from these in the size of caudal rami, in the characteristic shape of disto-medial part of coxa and basis of first to fourth pleopods (P1-P4) and in the presence of a single broad spinous expansion with a pointed tip in between exopod and endopod in basis of P1 to P4. Only one terminal spine is present in the second segment of endopod of P1. In P2 to P4, both exopod ...

Research paper thumbnail of Broodstock development, final oocyte maturation and breeding of the newly described sparid fish, Fanged seabream, Sparidentex jamalensis Amir, Siddiqui & Masroor, 2014

Research paper thumbnail of Central Marine Fisheries Research Institute, Karwar Research Centre, Karwar, Uttara Kannada, Karnataka, India

Research paper thumbnail of Seasonal abundance and diversity of finfish in a tropical estuary, Karwar, southwest coast of India

Journal of the Marine Biological Association of India, 2020

The spatial and seasonal variability in finfish availability in the tropical Kali Estuary, in Kar... more The spatial and seasonal variability in finfish availability in the tropical Kali Estuary, in Karwar was studied from January 2017-May 2019 at three stations. A total of 26 species belonging to 9 orders and 20 families were recorded from the Kali Estuary and the order Perciformes with 16 species dominated the group (62%) followed by order Mugilliformes and Pleuronectiformes (8%). Maximum abundance was observed during the pre-monsoon season in all the stations. Excluding Ambassis ambassis which was abundant in all the stations, Caranx ignobilis dominated in all the stations. Truly marine and estuarine species of fishes recorded dominated than the freshwater estuarine ones like Etroplus suratensis, Scatophagus argus, Aplocheilus lineatus. Number of species recorded at each station during the study ranged from 11 to 25 and it was significantly different between stations. The Shannon-Wiener diversity index ranged from 2.0 to 4.6, the minimum in station 1 and maximum in station 3. The seasonal analysis of diversity also showed minimum value during the monsoon season in station 1 and maximum value in station 3. The minimum value (2.2) of Margalef richness index was also recorded in Station 1 during monsoon season and maximum value (4.2) in Station 2. When comparing the relative abundance using Pielou's evenness index (J') the values were in the range of 0.92 to 0.99 which was closer to one, indicating evenness in distribution. There was similarity in species composition according to different seasons except for monsoon season in Station 1. The same pattern was also evident in the MDS plot where seasonal aggregation was observed between the stations. In addition to the diversity studies, the surveys also threw light on the abundance and seasonality of candidate species suitable for mariculture like C. ignobilis, Lutjanus spp., Etroplus spp., etc. Judicious exploitation of the species could help brackishwater fish farmers.

Research paper thumbnail of Induced breeding and larval rearing of vermiculated spinefoot, Siganus vermiculatus (Valenciennes, 1835) in indoor conditions

Aquaculture, 2021

Abstract Vermiculated spinefoot, Siganus vermiculatus has been reported to be one of the fastest ... more Abstract Vermiculated spinefoot, Siganus vermiculatus has been reported to be one of the fastest growing species among genus Siganus. Even though it breeds in captivity, commercial level hatchery production is yet to be achieved. In the present study, mature brooders of S. vermiculatus (female weighing 400 g and male weighing 385 g) were induced to breed in captivity and the larvae were reared to metamorphosis. Fishes (55 nos., 150 g–700 g) were collected from the wild and reared in marine cages using formulated floating pellets as feed. Among the mature fishes brought to the hatchery, a female having an average ova diameter of 440 μm and a running male were induced with two intramuscular injections of human chorionic gonadotropin (hCG) at the rate of 500 IU/ fish and 200 IU/ fish respectively in a spawning tank. Spawning occurred on the day after the full moon, between 20- and 21 h after the second injection. Fecundity was estimated as 1.85 lakhs with 68–71% of viable eggs and hatching rate of 73–85%. Green water systems with microalgae, Nannochloropsis salina and Isochrysis galbana at a concentration of 2–3 × 106 cells mL−1 and 2–3 × 105 cells mL−1 were used in tanks (1000L) for egg incubation and larval rearing respectively. Copepod, Parvocalanus crassirostris (T1) and enriched rotifer, Brachionus rotundiformis (S-type) (T2) were tested as first feed for newly hatched larvae. The fertilised eggs (0.57 ± 0.02 mm) hatched out between 24 and 25 h and the newly hatched larvae measured 1.92 ± 0.08 mm in total length with a transparent yolk sac (0.63 ± 0.04 mm) and an oil globule (0.23 ± 0.02 mm). Mouth gape of 89.03 ± 9.4 μm was observed after 42 h post hatch. The use of copepod, P. crassirostris as the first feed helped in successful rearing of the larvae to metamorphosis and an improved survival rate (4.5%–12%). Metamorphosis was completed within 35–37 dph, during which post larvae with vermiculated body pattern measured 25.2–28.4 mm in length and 0.28–0.30 g in weight. Enriched rotifers (5–37 dph), copepodites (10–20 dph), umbrella stage of Artemia (18–24 dph), artificial pellet feeds (21–37 dph) and enriched Artemia nauplii (29–37 dph) were also used during various stages of larviculture. The present study is the first report of induced breeding of S. vermiculatus during full moon phase of lunar cycle. The results of the present study also demonstrate a protocol for successful rearing of larvae to metamorphosis with P. crassirostris nauplii as first feed.

Research paper thumbnail of Characteristics, Pathogenicity and Antibiotic Sensitivity of Bacterial Isolates from White Spot Diseased Shrimp

Asian Fisheries Science

A bacteriological study was undertaken on white spot diseased shrimp collected from extensive, mo... more A bacteriological study was undertaken on white spot diseased shrimp collected from extensive, modified-extensive and semi-intensive ponds located at Visakhapatnam and East Godavari districts of North Coastal Andhra Pradesh. The diseased shrimp exhibited white spots and red discoloration of the body. Four species of bacteria, V. alginolyticus, V. parahaemolyticus, V. anguillarum and Pseudomonas aeruginosa were isolated from the hemolymph of the diseased shrimp. V. alginolyticus was found to be the most dominant and virulent species. All the bacterial isolates showed sensitivity towards oxytetracycline which is a commonly used antibiotic in culture ponds.

Research paper thumbnail of Cobia culture in low volume cages in coastal waters of Uttara Kannada, Karnataka

Cobia, Rachycentron canadum is a marine finfish globally favoured for aquaculture. In India, cage... more Cobia, Rachycentron canadum is a marine finfish globally favoured for aquaculture. In India, cage culture of cobia was first reported by ICAR-CMFRI in 2013 with better growth rate recorded under conditions of higher salinities (Philipose et al.2013). The present report is on the growth and production of cobia, Rachycentron canadum in Gangavali estuary (14o 61’ 225’’ N and 74 o35’726’’E) of coastal Karnataka during the period 2018-19

Research paper thumbnail of Argulus quadristriatus infestation in cage cultured Asian seabass

In Indian waters, genus Netuma is represented by two species namely N. bilineata and N. thalassin... more In Indian waters, genus Netuma is represented by two species namely N. bilineata and N. thalassina (Order: Siluriformes, Family: Ariidae). Rounded shout, thin lips, inconspicuous median longitudinal groove, and higher anal fin ray count (16-19) are characters of N. bilineata while N. thalassina has conical snout, clearly visible median longitudinal groove and lower anal fin ray count (13-15). Prior to the erection of N. bilineata (earlier considered as synonym of N. thalassina) as valid species, Indian workers had difference of opinion regarding the representation of species under this genus from Indian waters

Research paper thumbnail of Brief note on infestation of Diplectanum sp. inAsian seabass

Central Marine Fisheries Research Institute, 2019

Research paper thumbnail of Probiotic activity of Pseudomonas aeruginosa (PIC-4) isolated from Visakhapatnam coast, Bay of Bengal, India, against Vibrio harveyi in Penaeus monodon

International Journal of Fisheries and Aquatic Studies, 2014

Pseudomonas aeruginosa (PIC 4), isolated from coastal waters of Visakhapatnam (Gen Bank Accession... more Pseudomonas aeruginosa (PIC 4), isolated from coastal waters of Visakhapatnam (Gen Bank Accession no: KF803248) was tested for its antagonistic activity against Vibrio harveyi as probiotic in cultured Penaeus monodon. Pseudomonas aeruginosa PIC 4 has proved to be non-pathogenic to the shrimp by pathogenicity tests. Vibrio counts in probiotic fed shrimp and the surrounding water medium were significantly lower when compared to the control group of shrimp and water during 50 days of culture. Mean weight of probiont fed shrimps after 50 days of culture was (2.21 + 0.15 g) , significantly higher than that of normal diet fed ones (1.33+0.18 g). Survival percent was also significantly higher in probiont fed shrimp (47.33% + 5.55%) than that of the control diet fed shrimp (26.33% + 7%). Percent survival in probiotic fed and normal diet fed shrimp after the challenge with V. harveyi was 93.04 and 38.87 respectively.

Research paper thumbnail of Transportation of fingerlings and juveniles of marine finfish

There are two basic transport systems for live fish - the closed system and the open system. The ... more There are two basic transport systems for live fish - the closed system and the open system. The closed system is a sealed container in which all the requirements for survival are selfcontained. The simplest of these is a sealed plastic bag partly filled with water and oxygen. The open system consists of waterfilled containers in which the requirements for survival are supplied continuously from outside sources. The simplest of these is a small tank with an aerator stone.

Research paper thumbnail of Multiple Antibiotic Resistance pattern of Vibrio harveyi fromLuminous Vibriosis affected cultured Tiger Shrimp, Penaeus monodonin Andhra Pradesh, India

An investigation was undertaken to determine the extent of antibiotic resistance exhibited by Vib... more An investigation was undertaken to determine the extent of antibiotic resistance exhibited by Vibrio harveyi, isolated from diseased Penaeus monodon, collected from culture ponds located in East Godavari District of Andhra Pradesh. A total of 159 isolates of Vibrio harveyi, of which 110 are from four Modified-Extensive ponds (ME1, ME2, ME3, ME4) and 49 are from four Semi-Intensive ponds (SIA, SIB, SIC, SID), were screened for their susceptibility to 22 antibiotics. All the isolates from ME and SI ponds were resistant to penicillin G and 100% susceptibility was observed in the case of all the isolates of ME ponds towards Ciprofloxacin and Norfloxacin. The isolates from ME ponds were more resistant than those from SI ponds and the isolates of ME 1 pond exhibited 100% resistance towards eight antibiotics, whereas those of SI ponds were 100% resistant to only one antibiotic. A significant difference was observed in the Multiple Antibiotic Resistance (MAR) of the isolates from ME ponds, ...

Research paper thumbnail of Note on a bumper catch of Threadfin sea catfish in shore seine

For past several years catfish did not form a fishery at Karwar located in the Uttara Kannada Dis... more For past several years catfish did not form a fishery at Karwar located in the Uttara Kannada District of Karnataka. However, during the routine observations on the fish landings at Aligadda Fish Landing Centre, Karwar, an unusual bumper catch of about 3 tons of cat fish Arius arius was recorded from shore seine (Yendi bale) in the early hours of 28th July 2018. locally known as "Billi Shade", the catch was so heavy that it was difficult to drag the net to the shore and the haul was partially harvested at sea itself. The net operated by around 40 fishers at a depth of less than 8 metres, was 400 m in length.

Research paper thumbnail of Survival, Growth and Production of Penaeus monodon in Modified- Extensive and Semi Intensive Culture Systems of Andhra Pradesh, India

An analysis was made on the stocking density, survival, growth and production of Penaeus monodon ... more An analysis was made on the stocking density, survival, growth and production of Penaeus monodon in semi intensive (SI) and modified extensive (ME) shrimp culture ponds located in East Godavari district of Coastal Andhra Pradesh, India. Survival of shrimp in the ME systems with low stocking densities is higher (56 - 88%) than in the SI systems (12.3 – 52%) with higher stocking densities. Growth of shrimp is dependent not only on the stocking density but also on the management practices. Although the percent survival is more in ME system the growth is much faster in SI system owing to better management practices. Weight gain of shrimp was more rapid in the SI system than in the ME system initially up to 90 days of culture (DOC) but the trend was reverse in the later age of culture period. The optimum stocking density for achieving maximum production in the area is suggested as 10-15 individuals / m2 in SI ponds and 3-5 individuals / m2 in ME ponds.

Research paper thumbnail of Occurrence of concurrent infections with multiple viruses in Penaeus monodon from culture ponds of north coastal Andhra Pradesh

Current Science, 2002

A histopathological study of Penaeus monodon showing external symptoms of white spot disease, col... more A histopathological study of Penaeus monodon showing external symptoms of white spot disease, collected from culture ponds at Mulakuddu and Rambilli villages (Visakhapatnam District) during May and July 2001, provided evidence for the occurrence of multiple viral infections. Each diseased shrimp carried concurrent infections with four different viruses, identified on the basis of nuclear changes, resulting in the formation of characteristic inclusion/occlusion bodies, as WSSV, YHV, MBV and IHHNV. The identification of the various viruses needs confirmation through molecular diagnostic methods. This constitutes a report recording concurrent infections with multiple viruses in a single shrimp.

Research paper thumbnail of Open sea cage culture for marine finfish and shellfishes

Research paper thumbnail of Handbook on Opensea Cage Culture

The cage aquaculture has grown very rapidly during the past 20 years and is presently undergoing ... more The cage aquaculture has grown very rapidly during the past 20 years and is presently undergoing rapid changes in response to pressures from globalization and a growing global demand for aquatic products. Recent studies have predicted that fish consumption in developing and developed countries will increase by 57 percent and 4 percent, respectively. Rapid population growth, increasing affluence and urbanization in developing countries are leading to major changes in supply and demand for animal protein, from both livestock and fish. Within aquaculture production systems, there has been a move towards the clustering of existing cages as well as toward the development and use of more intensive cage-farming systems. In particular, the need for suitable sites has resulted in the cage culture sector accessing and expanding into new untapped open-water culture areas such as coastal brackish and marine offshore waters.

Research paper thumbnail of Loose shell syndrome (LSS) of cultured Penaeus monodon - microbiological and histopathological investigations

Indian Journal of Fisheries, 2012

Investigations were undertaken on loose shell syndrome (LSS) of cultured Penaeus monodon during t... more Investigations were undertaken on loose shell syndrome (LSS) of cultured Penaeus monodon during the period 2009 - 2010. The infected shrimps were collected from culture ponds of east and west Godavari districts in Andhra Pradesh, India and were subjected to microbiological and histopathological studies. Four species of Vibrio were isolated from the diseased shrimps and were identified as V. harveyi, V. alginolyticus, V. metschnikovii and V. fluvialis based on morphological characteristics and biochemical tests. Histopathological studies revealed the presence of occlusion and inclusion bodies of monodon baculovirus (MBV), hepatopancreatic parvo-like virus (HPV), and white spot syndrome virus (WSSV) in hepatopancreatic and gill tissues. All the LSS affected shrimps collected during the present study were found infected with V. harveyi and concurrent infections of other Vibrio species were observed in 40% of the samples. Prevalence of infection with WSSV, MBV and HPV was less compared ...

Research paper thumbnail of Broodstock development, breeding and larval rearing of Acanthopagrus berda (Forsskal, 1775), a suitable species for farming in tropical waters

Research paper thumbnail of Standardization of culture aspects of Apocyclops cmfri sp. nov. a nativecyclopoid copepod

Copepods are considered as ideal larval feed, due to their smaller size (<100μm), high protein... more Copepods are considered as ideal larval feed, due to their smaller size (<100μm), high protein and favourable fatty acid profiles. There are three types of copepods viz., harpacticoid, calanoid and cyclopoid, which can be cultured on a large scale under controlled conditions as live feed for the initial stages of fish and shellfish larvae. Karwar Research Centre of ICAR- CMFRI made a significant contribution in standardizing the protocols for the culture of a new cyclopoid copepod,

Research paper thumbnail of Apocyclops cmfri sp. nov. (Cyclopoda : Cyclopoida : Cyclopidae), a new copepod species from marine waters of Karwar, Karnataka, India

Indian Journal of Fisheries

A new species of Apocyclops Lindberg (Cyclopoda: Cyclopoida: Cyclopidae) is described based on sp... more A new species of Apocyclops Lindberg (Cyclopoda: Cyclopoida: Cyclopidae) is described based on specimens collected from marine waters of Karwar, Karnataka, India. At present, there are 11 valid and accepted species excluding one extinct species (fossil) in this genus which are widely distributed in fresh and brackishwater areas in the tropics and subtropics. Five valid species of Apocyclops are reported from the Asian region, including two species from India. The new species is closer to the previously reported Indian species, A. royi (Lindberg) and A. dengizicus dengizicus (Lepeshkin). Apocyclops cmfri sp. nov. differs from these in the size of caudal rami, in the characteristic shape of disto-medial part of coxa and basis of first to fourth pleopods (P1-P4) and in the presence of a single broad spinous expansion with a pointed tip in between exopod and endopod in basis of P1 to P4. Only one terminal spine is present in the second segment of endopod of P1. In P2 to P4, both exopod ...

Research paper thumbnail of Broodstock development, final oocyte maturation and breeding of the newly described sparid fish, Fanged seabream, Sparidentex jamalensis Amir, Siddiqui & Masroor, 2014

Research paper thumbnail of Central Marine Fisheries Research Institute, Karwar Research Centre, Karwar, Uttara Kannada, Karnataka, India

Research paper thumbnail of Seasonal abundance and diversity of finfish in a tropical estuary, Karwar, southwest coast of India

Journal of the Marine Biological Association of India, 2020

The spatial and seasonal variability in finfish availability in the tropical Kali Estuary, in Kar... more The spatial and seasonal variability in finfish availability in the tropical Kali Estuary, in Karwar was studied from January 2017-May 2019 at three stations. A total of 26 species belonging to 9 orders and 20 families were recorded from the Kali Estuary and the order Perciformes with 16 species dominated the group (62%) followed by order Mugilliformes and Pleuronectiformes (8%). Maximum abundance was observed during the pre-monsoon season in all the stations. Excluding Ambassis ambassis which was abundant in all the stations, Caranx ignobilis dominated in all the stations. Truly marine and estuarine species of fishes recorded dominated than the freshwater estuarine ones like Etroplus suratensis, Scatophagus argus, Aplocheilus lineatus. Number of species recorded at each station during the study ranged from 11 to 25 and it was significantly different between stations. The Shannon-Wiener diversity index ranged from 2.0 to 4.6, the minimum in station 1 and maximum in station 3. The seasonal analysis of diversity also showed minimum value during the monsoon season in station 1 and maximum value in station 3. The minimum value (2.2) of Margalef richness index was also recorded in Station 1 during monsoon season and maximum value (4.2) in Station 2. When comparing the relative abundance using Pielou's evenness index (J') the values were in the range of 0.92 to 0.99 which was closer to one, indicating evenness in distribution. There was similarity in species composition according to different seasons except for monsoon season in Station 1. The same pattern was also evident in the MDS plot where seasonal aggregation was observed between the stations. In addition to the diversity studies, the surveys also threw light on the abundance and seasonality of candidate species suitable for mariculture like C. ignobilis, Lutjanus spp., Etroplus spp., etc. Judicious exploitation of the species could help brackishwater fish farmers.

Research paper thumbnail of Induced breeding and larval rearing of vermiculated spinefoot, Siganus vermiculatus (Valenciennes, 1835) in indoor conditions

Aquaculture, 2021

Abstract Vermiculated spinefoot, Siganus vermiculatus has been reported to be one of the fastest ... more Abstract Vermiculated spinefoot, Siganus vermiculatus has been reported to be one of the fastest growing species among genus Siganus. Even though it breeds in captivity, commercial level hatchery production is yet to be achieved. In the present study, mature brooders of S. vermiculatus (female weighing 400 g and male weighing 385 g) were induced to breed in captivity and the larvae were reared to metamorphosis. Fishes (55 nos., 150 g–700 g) were collected from the wild and reared in marine cages using formulated floating pellets as feed. Among the mature fishes brought to the hatchery, a female having an average ova diameter of 440 μm and a running male were induced with two intramuscular injections of human chorionic gonadotropin (hCG) at the rate of 500 IU/ fish and 200 IU/ fish respectively in a spawning tank. Spawning occurred on the day after the full moon, between 20- and 21 h after the second injection. Fecundity was estimated as 1.85 lakhs with 68–71% of viable eggs and hatching rate of 73–85%. Green water systems with microalgae, Nannochloropsis salina and Isochrysis galbana at a concentration of 2–3 × 106 cells mL−1 and 2–3 × 105 cells mL−1 were used in tanks (1000L) for egg incubation and larval rearing respectively. Copepod, Parvocalanus crassirostris (T1) and enriched rotifer, Brachionus rotundiformis (S-type) (T2) were tested as first feed for newly hatched larvae. The fertilised eggs (0.57 ± 0.02 mm) hatched out between 24 and 25 h and the newly hatched larvae measured 1.92 ± 0.08 mm in total length with a transparent yolk sac (0.63 ± 0.04 mm) and an oil globule (0.23 ± 0.02 mm). Mouth gape of 89.03 ± 9.4 μm was observed after 42 h post hatch. The use of copepod, P. crassirostris as the first feed helped in successful rearing of the larvae to metamorphosis and an improved survival rate (4.5%–12%). Metamorphosis was completed within 35–37 dph, during which post larvae with vermiculated body pattern measured 25.2–28.4 mm in length and 0.28–0.30 g in weight. Enriched rotifers (5–37 dph), copepodites (10–20 dph), umbrella stage of Artemia (18–24 dph), artificial pellet feeds (21–37 dph) and enriched Artemia nauplii (29–37 dph) were also used during various stages of larviculture. The present study is the first report of induced breeding of S. vermiculatus during full moon phase of lunar cycle. The results of the present study also demonstrate a protocol for successful rearing of larvae to metamorphosis with P. crassirostris nauplii as first feed.

Research paper thumbnail of Characteristics, Pathogenicity and Antibiotic Sensitivity of Bacterial Isolates from White Spot Diseased Shrimp

Asian Fisheries Science

A bacteriological study was undertaken on white spot diseased shrimp collected from extensive, mo... more A bacteriological study was undertaken on white spot diseased shrimp collected from extensive, modified-extensive and semi-intensive ponds located at Visakhapatnam and East Godavari districts of North Coastal Andhra Pradesh. The diseased shrimp exhibited white spots and red discoloration of the body. Four species of bacteria, V. alginolyticus, V. parahaemolyticus, V. anguillarum and Pseudomonas aeruginosa were isolated from the hemolymph of the diseased shrimp. V. alginolyticus was found to be the most dominant and virulent species. All the bacterial isolates showed sensitivity towards oxytetracycline which is a commonly used antibiotic in culture ponds.

Research paper thumbnail of Cobia culture in low volume cages in coastal waters of Uttara Kannada, Karnataka

Cobia, Rachycentron canadum is a marine finfish globally favoured for aquaculture. In India, cage... more Cobia, Rachycentron canadum is a marine finfish globally favoured for aquaculture. In India, cage culture of cobia was first reported by ICAR-CMFRI in 2013 with better growth rate recorded under conditions of higher salinities (Philipose et al.2013). The present report is on the growth and production of cobia, Rachycentron canadum in Gangavali estuary (14o 61’ 225’’ N and 74 o35’726’’E) of coastal Karnataka during the period 2018-19

Research paper thumbnail of Argulus quadristriatus infestation in cage cultured Asian seabass

In Indian waters, genus Netuma is represented by two species namely N. bilineata and N. thalassin... more In Indian waters, genus Netuma is represented by two species namely N. bilineata and N. thalassina (Order: Siluriformes, Family: Ariidae). Rounded shout, thin lips, inconspicuous median longitudinal groove, and higher anal fin ray count (16-19) are characters of N. bilineata while N. thalassina has conical snout, clearly visible median longitudinal groove and lower anal fin ray count (13-15). Prior to the erection of N. bilineata (earlier considered as synonym of N. thalassina) as valid species, Indian workers had difference of opinion regarding the representation of species under this genus from Indian waters

Research paper thumbnail of Brief note on infestation of Diplectanum sp. inAsian seabass

Central Marine Fisheries Research Institute, 2019

Research paper thumbnail of Probiotic activity of Pseudomonas aeruginosa (PIC-4) isolated from Visakhapatnam coast, Bay of Bengal, India, against Vibrio harveyi in Penaeus monodon

International Journal of Fisheries and Aquatic Studies, 2014

Pseudomonas aeruginosa (PIC 4), isolated from coastal waters of Visakhapatnam (Gen Bank Accession... more Pseudomonas aeruginosa (PIC 4), isolated from coastal waters of Visakhapatnam (Gen Bank Accession no: KF803248) was tested for its antagonistic activity against Vibrio harveyi as probiotic in cultured Penaeus monodon. Pseudomonas aeruginosa PIC 4 has proved to be non-pathogenic to the shrimp by pathogenicity tests. Vibrio counts in probiotic fed shrimp and the surrounding water medium were significantly lower when compared to the control group of shrimp and water during 50 days of culture. Mean weight of probiont fed shrimps after 50 days of culture was (2.21 + 0.15 g) , significantly higher than that of normal diet fed ones (1.33+0.18 g). Survival percent was also significantly higher in probiont fed shrimp (47.33% + 5.55%) than that of the control diet fed shrimp (26.33% + 7%). Percent survival in probiotic fed and normal diet fed shrimp after the challenge with V. harveyi was 93.04 and 38.87 respectively.

Research paper thumbnail of Transportation of fingerlings and juveniles of marine finfish

There are two basic transport systems for live fish - the closed system and the open system. The ... more There are two basic transport systems for live fish - the closed system and the open system. The closed system is a sealed container in which all the requirements for survival are selfcontained. The simplest of these is a sealed plastic bag partly filled with water and oxygen. The open system consists of waterfilled containers in which the requirements for survival are supplied continuously from outside sources. The simplest of these is a small tank with an aerator stone.

Research paper thumbnail of Multiple Antibiotic Resistance pattern of Vibrio harveyi fromLuminous Vibriosis affected cultured Tiger Shrimp, Penaeus monodonin Andhra Pradesh, India

An investigation was undertaken to determine the extent of antibiotic resistance exhibited by Vib... more An investigation was undertaken to determine the extent of antibiotic resistance exhibited by Vibrio harveyi, isolated from diseased Penaeus monodon, collected from culture ponds located in East Godavari District of Andhra Pradesh. A total of 159 isolates of Vibrio harveyi, of which 110 are from four Modified-Extensive ponds (ME1, ME2, ME3, ME4) and 49 are from four Semi-Intensive ponds (SIA, SIB, SIC, SID), were screened for their susceptibility to 22 antibiotics. All the isolates from ME and SI ponds were resistant to penicillin G and 100% susceptibility was observed in the case of all the isolates of ME ponds towards Ciprofloxacin and Norfloxacin. The isolates from ME ponds were more resistant than those from SI ponds and the isolates of ME 1 pond exhibited 100% resistance towards eight antibiotics, whereas those of SI ponds were 100% resistant to only one antibiotic. A significant difference was observed in the Multiple Antibiotic Resistance (MAR) of the isolates from ME ponds, ...

Research paper thumbnail of Note on a bumper catch of Threadfin sea catfish in shore seine

For past several years catfish did not form a fishery at Karwar located in the Uttara Kannada Dis... more For past several years catfish did not form a fishery at Karwar located in the Uttara Kannada District of Karnataka. However, during the routine observations on the fish landings at Aligadda Fish Landing Centre, Karwar, an unusual bumper catch of about 3 tons of cat fish Arius arius was recorded from shore seine (Yendi bale) in the early hours of 28th July 2018. locally known as "Billi Shade", the catch was so heavy that it was difficult to drag the net to the shore and the haul was partially harvested at sea itself. The net operated by around 40 fishers at a depth of less than 8 metres, was 400 m in length.

Research paper thumbnail of Survival, Growth and Production of Penaeus monodon in Modified- Extensive and Semi Intensive Culture Systems of Andhra Pradesh, India

An analysis was made on the stocking density, survival, growth and production of Penaeus monodon ... more An analysis was made on the stocking density, survival, growth and production of Penaeus monodon in semi intensive (SI) and modified extensive (ME) shrimp culture ponds located in East Godavari district of Coastal Andhra Pradesh, India. Survival of shrimp in the ME systems with low stocking densities is higher (56 - 88%) than in the SI systems (12.3 – 52%) with higher stocking densities. Growth of shrimp is dependent not only on the stocking density but also on the management practices. Although the percent survival is more in ME system the growth is much faster in SI system owing to better management practices. Weight gain of shrimp was more rapid in the SI system than in the ME system initially up to 90 days of culture (DOC) but the trend was reverse in the later age of culture period. The optimum stocking density for achieving maximum production in the area is suggested as 10-15 individuals / m2 in SI ponds and 3-5 individuals / m2 in ME ponds.

Research paper thumbnail of Occurrence of concurrent infections with multiple viruses in Penaeus monodon from culture ponds of north coastal Andhra Pradesh

Current Science, 2002

A histopathological study of Penaeus monodon showing external symptoms of white spot disease, col... more A histopathological study of Penaeus monodon showing external symptoms of white spot disease, collected from culture ponds at Mulakuddu and Rambilli villages (Visakhapatnam District) during May and July 2001, provided evidence for the occurrence of multiple viral infections. Each diseased shrimp carried concurrent infections with four different viruses, identified on the basis of nuclear changes, resulting in the formation of characteristic inclusion/occlusion bodies, as WSSV, YHV, MBV and IHHNV. The identification of the various viruses needs confirmation through molecular diagnostic methods. This constitutes a report recording concurrent infections with multiple viruses in a single shrimp.

Research paper thumbnail of Open sea cage culture for marine finfish and shellfishes

Research paper thumbnail of Handbook on Opensea Cage Culture

The cage aquaculture has grown very rapidly during the past 20 years and is presently undergoing ... more The cage aquaculture has grown very rapidly during the past 20 years and is presently undergoing rapid changes in response to pressures from globalization and a growing global demand for aquatic products. Recent studies have predicted that fish consumption in developing and developed countries will increase by 57 percent and 4 percent, respectively. Rapid population growth, increasing affluence and urbanization in developing countries are leading to major changes in supply and demand for animal protein, from both livestock and fish. Within aquaculture production systems, there has been a move towards the clustering of existing cages as well as toward the development and use of more intensive cage-farming systems. In particular, the need for suitable sites has resulted in the cage culture sector accessing and expanding into new untapped open-water culture areas such as coastal brackish and marine offshore waters.