2020

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Changes in Electrophoretic patterns of Sarcoplasmic Proteins and Myofibrillar Proteins in Caranx melampygus (Cuvier, 1833) during chilled storage
(Society of Fisheries Technologists (India), 2020) Hassan, Femeena; Nija, K. V.
SDS-PAGE studies were conducted to apprehend the changes in the electrophoretic pattern of myofibrillar and sarcoplasmic proteins of Caranx melampygus (Cuvier, 1833) (Blue fin Trevally) during chilled storage. The study revealed that the intensity of Myosin bands were getting reduced during storage. The relative front of myosin band was getting decreased during storage.The relative front on initial day for myosin is 0.331 and it decreased to 0.303 on 12thday of storage. In protein profile, molecular weights of protein bands were found to be 191.8kDa, 99.1 kDa, 52.0 kDa for myofibrillar proteins on initial day, and 200.0 kDa, 101.4 kDa, 51.5 kDa on 12th day. Molecular weights of protein bands were found to be 97.4 kDa, 60.3 kDa, 50.9 kDa, 30.4 kDa, 29.2 kDa, 26.8 kDa, 25.6 kDa, 21.5 kDa for sarcoplasmic proteins on initial day and 97.4 kDa, 61.1 kDa, 52.1 kDa, 45.8 kDa, 34.6 kDa, 30.0 kDa, 26.1 kDa ,21.5 kDa respectively on 12th day. The number of bands for sarcoplasmic proteins and myofibrillar proteins of Caranx melampygus were same on initial day and final day of storage (9 and 3 respectively).
Enzymatic and Fermentatively Produced Rohu (Labeo rohita) Sauce and its Biochemical and Microbiological Quality
(Society of Fisheries Technologists (India), 2020) Siddegowda, G. S.; Bhaskar, N.; Gopal, Shubha
Rohu (Labeo rohita) sauce was produced by enzymatic and fermentative method using optimized conditions carried out through response surface method. Solar salt (20%, w/w) and commercial papain (3%, w/w) were used in the sauce produced by enzymatic method. The optimized conditions for fermentative production of sauce were 25% salt (w/ w), 7.5% sugar (w/w) and 10% (w/v) inoculum (Pediococcus pentosaceus FSBP4-40) with the cell concentration of approximately 8 log cfu ml-1. The sauces produced by enzymatic and fermentative method were stored at room temperature and 37°C, respectively for 180 days. Changes in yield, water activity (aw), total volatile base nitrogen (TVB-N), total soluble nitrogen (TSN), non protein nitrogen (NPN), titratable acidity (TA), degree of hydrolysis (DH) and fatty acid composition of both the sauce samples were observed. The result suggested that TSN, NPN, TA and DH significantly increased (p<0.05) in treated samples compared to control (sample without added papain and P. pentosaceus FSBP4-40). However, aw, pH, moisture, fat , TVB-N, fatty acid concentration and L*, a*, b* values showed different changes. Sensory properties of enzyme treated sauce had slightly higher score than the lactic acid bacteria fermented sauce. Bacterial counts after 180 d were significantly lower (p<0.05) in the fermentatively produced rohu sauce than enzymatically prepared sauce. The study emphasizes the importance of optimized use of enzyme and native lactic acid bacteria for the acceleration of fermentation process to produce biofunctionally and bacteriologically superior rohu sauce.
Length-Girth Relationships of Selected Trawl Resources of Cochin Coast, Kerala
(Society of Fisheries Technologists (India), 2020) Naseeba, P. A.; Madhu, V. R.; Kumar, B. Manoj; Edwin, Leela
Trawling is a major fishing method which contributes significantly to the marine catches of India. Among the many negative impacts that are attributed to trawling, generation of bycatch is the most significant and different technical measures have been adopted world over to reduce bycatch during trawling operations. The optimum mesh size for a technical device is determined by conducting selectivity experiments using different methods, in which length is the main criteria for analysis. However, fish retention in the codend is primarily decided by the girth rather than length, which is often difficult to measure in field and hence length is taken as a proxy for girth. Knowledge of the length-girth relationships of major species would be an additional input for designing gears and deriving an optimum mesh size/shape for trawl codends. The length-girth relationships of 15 commercially important species targeted by trawls along Cochin coast were derived. The results indicated that thirteen of these species had no significant variation in the value of slope, whereas for Pampus argenteus and Trichiurus lepturus, the values for the slope, differed significantly (p<0.05, t-test) indicating that the mesh size requirement would be different for these species. Though estimates did not consider the sex or condition of the fishes studied, the results of the study will be an added input for deriving selectivity estimates
Fluoride Removal from Water using Chitosan Coated Activated Carbon and Cuttle Bone Ash in Combination with Alumina
(Society of Fisheries Technologists (India), 2020) Laly, S. J.; Priya, E. R.; Zynudheen, A. A.
Fluoride contamination of ground water is an important health concern globally. Presence of high level of fluoride in drinking water can lead to issues of skeletal and dental fluorosis. A combination of chitosan coated activated carbon (CCAC) and chitosan coated cuttle bone ash (CCBA) along with alumina was used for the removal of fluoride from drinking water. The sorbents were characterized by SEM and FTIR. Combination of 2.5% CCAC and 1% alumina resulted a fluoride removal efficiency of 85.4%, while a 2% CCBA and 2% alumina combination resulted removal of 96.6%, also the fluoride removal efficiency increased along with increase of contact time (p<0.01). At higher initial fluoride concentrations, CCBA was more effective in fluoride removal than CCAC in combination with alumina. This information can help in modeling and designing of filtration devices with these adsorbents for effectively managing fluoride - contaminated ground water.
Gendered Differences in Nutritional status of Fish Consuming Households in Kerala, India
(Society of Fisheries Technologists (India), 2020) Jeyanthi, Pe. Jeyya; . Sankar, T.V; Anandan, R.; Mathew, Suseela; Gopal, Nikita
Abstract Malnutrition, the deficiencies, excesses or imbalances in a person’s intake of energy and/or nutrients, covers two groups of conditions viz., ‘under nutrition’ and ‘over nutrition’. Malnutrition impacts globally across households, communities and countries with 0.46 and 1.90 billion adults being in under and over nutrition conditions, respectively. The level of malnutrition is generally higher among women and children. A cross-sectional study was undertaken to assess the nutritional status in Vadi and Kottarakkara villages, Kollam District, Kerala, India with emphasis on gender differences in the nutritional status of fish consuming households. The Body Mass Index (BMI) of children, adolescents and adults was calculated as per World Health Organisation (WHO) classification. In coastal village, 55% of boys and girls were of normal weight, and in non-coastal village 40.74% boys and 60.47% girls were normal weight. BMI of adolescents showed that 55.17% of boys and 63.64% girls were underweight. Majority of adults (64.71%) showed normal weight which included 56% women and 73% men. There is no prominent gender difference in nutritional status and demography, literacy and job were found to influence the nutritional status of fishers.
Biosurfactants and its Applications in Aquaculture
(Society of Fisheries Technologists (India), 2020) Nadella, Ranjit Kumar; Muthulakshmi, T.; Minimol, V. A.; Murugadas, V.; Basha, K. A.; Joseph, Toms C.; Prasad, M. M.
Aquatic environments harbour a wide diversity of microorganisms that produce several novel compounds. Biosurfactant is a compound synthesized by microorganisms which have distinct physiological and metabolic pathways. Structurally they are amphiphilic molecules with hydrophilic moiety (tail) and hydrophobic moiety (head) that accumulates between two fluid phases and reduces surface tension. The property of a particular biosurfactant molecule is dependent on the location as well as the size of the functional groups. These biosurfactants can form strong emulsions at wide ranges of pH and temperature. The physico-chemical and biological properties are unique which makes the biosurfactant widely applicable in different fields, including aquaculture. Most common applications include inhibition of quorum sensing mechanism of the bacterial communication and inhibiting the growth of pathogenic bacteria. In case of fish feed processing industries, the emulsions formed by the biosurfactant can be incorporated into diet. The micelle forming property of the biosurfactant can be exploited for developing targeted drug delivery techniques. The methodologies and techniques for screening potential microorganisms which produce biosurfactant from aquatic environment and its application in aquaculture sector assume great importance. This communication provides a detailed review on the developments in these areas.
Process Standardization of Ready-to-eat Pasteurized Crab spread from Marine Blue Swimming Crab (Portunus pelagicus) Incorporated with Threadfin Bream Surimi
(Society of Fisheries Technologists (India), 2020) Thomas, Seba T. Jiso; Archana, G.; Abhilash, S.; Sabu, S.; Sunooj, K. V.; Gopal, T. K. S.
Ready-to-eat pasteurized crab spread was standardized from blue swimming crab (Portunus pelagicus) and surimi from threadfin bream (Nemipterus japonicus). Spread was prepared incorporating crab meat and surimi in 1:1 ratio, vacuum packed in monolayer retortable polypropylene pouches with screw cap and pasteurized to core temperatures 86oC[T1] and 89oC[T2] for a total processing time of 90 min and 50 min, respectively. Both the spreads were subjected to proximate, organoleptic and microbial analysis for the assessment of shelf life under chilled condition (3oC) for six months. The pH values of T1 and T2 reduced during the storage period (p<0.001). Total Volatile Base Nitrogen (TVBN), Trimethylamine Nitrogen (TMA-N), Peroxide Value (PV) and Free Fatty Acid (FFA) values were within the acceptable limits up to 176 days of storage (p<0.001). Both the spreads were analyzed for anaerobic growth and found sterile. The crab spread processed at 86oC (T1) showed superior sensory characteristics throughout the refrigerated storage (3oC) and found to be stable and acceptable.
Consumer Preference of Fish and Fish Products in Peri- Urban Households of Bhubaneswar, Odisha
(Society of Fisheries Technologists (India), 2020) Tanuja, S.; Jeeva, J. C.; Rout, E.; Srivastava, S. K.
Fish consumption surveys constitute an important information input for public policies on marketing, public health and product development. This paper examines the consumer preference for the value added fish products by conducting a survey of 150 consumers in the peri-urban areas of Bhubaneswar during the year 2018-19. All the consumers were aware about one or other parameters to assess the freshness of fish. Almost half of the consumers (46.67%) were aware that fish is a good source of quality protein, and 30% were of the opinion that fish is rich in omega 3 fatty acids and is good for neonatal brain development. About 10% of them consumed fresh fish every day. About 40% of the consumers responded that they consume value added fish products, dry fish, once in a month. About 7% of the consumers responded that they never consume dry fish as hygienically produced dry fish is not available in the market. All the consumers were interested in consuming one or other forms of value added products from fish, almost half of them (50%) preferring fish cutlet. Price, taste and health factor were perceived as the most important attributes of value added fish products. The consumers though willing to purchase value added fish products, were not ready to accept the prevailing market rates of these products in states outside Odisha. Strategies like promoting fish value added products will provide the much needed alternative livelihood options especially for fisherwomen.
Present Status of Heavy Metals in Lake Nainital, India
(Society of Fisheries Technologists (India), 2020) Joshi, Pawan Kumar; Mishra, Ashutosh; Trakroo, M. Das
To evaluate heavy metal pollution status of the Lake Nainital, an eutrophic lake, situated in the Central West Himalayan region at 29°24’ N latitude, 79°28’ E longitude and an altitude of 1935 m above mean sea level, the assessment of heavy metals in the lake water was made from September 2016 to February 2017 using Atomic Absorption Spectrophotometer (AAS). Three sites viz., S1 (Aeration centre at thandi sadak), S2 (Platform near the Naina Devi Temple) and S3 (Boat stand near bus stand) were selected and fortnightly sampling for assessing the concentration of six selected heavy metals (Lead, Cadmium, Arsenic, Zinc, Copper and Manganese) was made. The range and average concentration of heavy metals in water of Lake Nainital was observed as Zn: 0.013- 0.051 (0.029 mg L-1), Pb: 0.137- 0.629 (0.346 mg L-1), Cu: 0.0- 0.263(0.113 mg L-1), Mn: 0.0- 1.314 (0.361 mg L-1), Cd: 0.0- 0.012 (0.007 mg L-1) and As: 0.0- 0.004 (0.001 mg L-1). Three water quality pollution indices namely Heavy metal Pollution Index (HPI), Heavy metal Evaluation Index (HEI) and Degree of Contamination (Cd) were used to evaluate the present status of selected heavy metals. The average value of heavy metal pollution index of different metals (Zn: 0.005, Pb: 6.438, Cu: 0.066, Mn: 1.642, Cd: 0.610 and As: 0.205) show that the water of Lake Nainital is slightly affected with Mn and seriously affected with Pb pollution. Though the average value of HEI (1.448) and Cd (0.447) suggests low heavy metal pollution in the Lake Nainital, higher lead pollution is case of concern.
Comparative Analysis of Consumer Behaviour between Traditional Fish Markets and Modern Retail Outlets in Kolkata, West Bengal
(Society of Fisheries Technologists (India), 2020) Bhutia, Tenji Pem; Yadav, Vinod Kumar; Qureshi, Neha Wajahat; Kumar, Nalini Ranjan; Ojha, Shekhar Nath
The present study was conducted in Kolkata, to examine if there is any difference in consumer behavior from traditional fish markets to modern fish markets. The survey included 300 households, 150 each from the traditional fish markets and modern retail outlets. The perception study showed that 49, 70 and 61% of the respondents perceived quality, variety and price of fish as good, plenty and reasonable, respectively in traditional fish markets, while 67, 53 and 49% of the consumers perceived quality, variety and price as average, very few and very high respectively in modern retail markets. Perception index score revealed that 82.67% had perceived traditional market as good (>0.66) in the context of quality, variety and price, while modern retail outlets are perceived poor, (<0.33) by 62% of consumers. The regression adjustment model revealed that anticipated expenditure of consumer on fish and fish products was Rs. 980 more in modern retail outlets than the traditional fish markets. To enhance the efficiency and enhance consumer’s satisfaction, modern retailers should increase the variety of fishes while traditional markets need to improve hygiene.
Biofilm developed on plant substrates enhances growth and survival of post larvae of Macrobrachium rosenbergii
(Society of Fisheries Technologists (India), 2020) Thomas, Shilta Madathumpady; Lalramchhani, Christina; Lalrinsanga, P. L.; Pillai, Bindu
A five-week laboratory experiment was conducted to evaluate the efficacy of plant-based substrates for biofilm production and their effect on water quality as well as growth and survival of freshwater prawn Macrobrachium rosenbergii (De Man, 1879) postlarvae. The experiment consisted of three treatments with a control, each with three replicates following a completely randomized design. The substrates evaluated were dried sugarcane bagasse (T1), paddy straw (T2) and Eichhornia (T3). Tanks without substrates acted as control. Seven days after the introduction of substrates at the rate of 300 g /tank, post-larvae were stocked at 40 nos/m2. The mean initial length and weight of the post-larvae was 10.3 mm and 0.008 g, respectively. The post-larvae were fed with commercial pellet feed (30% protein) at 20% of initial biomass. Results revealed significantly higher (p<0.05) levels of total ammonia- nitrogen, nitrite-nitrogen and nitrate-nitrogen in the control tanks (0.07 ±.004 mg L-1; 0.03 ±.01 mg L-1; 1.40 ±.05 mg L-1, respectively) compared to treatment tanks. Addition of natural substrates enhanced survival and growth of post-larvae with highest growth recorded in paddy straw (0.15 ±0.05 g) followed by sugarcane bagasse (0.14±0.04 g) and Eichhornia (0.10±0.01 g) treatment. The enhancement of growth of PL in natural substrate corresponds to the heterotrophic bacteria that are using the substrate, probably as a food resource and as a probiotic. Further, there was no water exchange during the experimental period, which indicated that the presence of a biofilm reduces the necessity of water exchange and saves water during the postlarval rearing of M. rosenbergii at this density.
Quality characteristics and stability of chicken cutlet fortified with Fish Protein Hydrolysate (FPH)
(Society of Fisheries Technologists (India), 2020) Raj, Rehana; Varghese, Shiby; Tabassum, Aisha
Fish Protein Hydrolysate (FPH) was incorporated in chicken cutlet to study its effect on quality aspects and storage stability. FPH was added at four different concentrations viz., 0, 5, 10 and 15%. It was observed that 15% FPH in chicken cutlet gave a better cooking yield of 63.64 ± 0 .08% and a lower cooking loss of 36.55± 0.53%. Hence 15% FPH among the treatment groups was used for the formulation of chicken cutlet with various proportions of chicken and binder (60% chicken and 40% potato, 70% chicken and 30% potato, 80% chicken and 20% potato) for optimization. The combination of 70% chicken and 30% binder exhibited low oil uptake, minimum shrinkage, optimum pH, and overall acceptability during sensory evaluation (OA). Finally, the optimised combination of 70:30 was used to prepare the chicken cutlet and analysed for the storage stability by MAP and Normal Packaging. It was observed that the oxidative parameters such as PV, TBARS and TPC were lower for the samples which were given MAP. OA was highest for the samples with MAP. It could be concluded that FPH imparts a positive impact on storage stability and quality parameters of chicken cutlet.
Analysis of Marine Products Export from India using Markov-Chain Analysis
(Society of Fisheries Technologists (India), 2020) Chandrasekar, V.; Paramasivam, P.; Jayanthi, C.; Sathy, R.; Gopal, Nikita; Mani, K.
The present study analyses the changing pattern of marine product exports from India to seven regions/ countries such as Japan, USA, European Union (E.U), China, South East Asia (SEA), Middle East (ME) and others, during two decades from 1995 to 2015. The average growth rate of marine seafood export in relation to quantity and value for the two decades was 6.78 and 12.5% respectively. Frozen shrimp export quantity had nearly 40% share in the total export basket. Instability in value was higher than the quantity of export, out of which frozen shrimp price instability was nearly 60%. Using Markov Chain Analysis, it was observed that European Union was having higher probability of retention (0.82) compared to the other regions. In the first decade Japan was the major importer with higher probability of retention which reduced from 0.91 to 0.56 during the second decade with a gain by European Union (0.87) in the same decade.
Development of Low Drag Trawls for Energy Efficient Fishing
(Society of Fisheries Technologists (India), 2020) Remesan, M. P.; Sayana, K. A.; Madhu, V. R.; Pravin, P.; Thomas, Saly N.; Edwin, Leela
Trawl drag is an important factor determining the energy efficiency and profitability of trawling. Drag experienced during trawling depends on the design, rigging, accessories of the net, hydrographic and dragging conditions and has a direct bearing on fuel consumption. Fuel cost can alone constitute up to 75% of the operational expenditure of a trawler. Stronger materials will permit the use of thinner twines to reduce twine surface area and hence drag. Empirical estimations of drag of different commercial trawl nets in Kerala showed it to range from 1.37 to 48.94 kN. Comparative fishing trials were carried out with 24 m trawls made of HDPE twine and ultra-high molecular weight polyethylene (UHMWPE). Study revealed that average fuel consumption of HDPE trawls was 31.86±1.25 l-h whereas it was 25.31±1.38 l-h for UHMWPE trawl. CPUE were 8.1 kg h-1 and 7.9 kg h-1 for UHMWPE trawl and HDPE trawl respectively. Results shows that material substitution, coupled with improvement in trawl design, appropriate gear accessories and towing speed can help significantly in reducing the drag and concurrent reduction in fuel use.
Culture Medium and Growth Phase Modulate the Fatty Acid Composition of the Diatom Nitzschia palea (Kutzing) W. Smith-Potential Source for Live Feed and Biodiesel
(Society of Fisheries Technologists (India), 2020) Krishnan, Aswathy; Anandan, R.; Joseph, Aneykutty
The fresh water diatom Nitzschia palea was cultured in four different culture media viz., f/2, Walne’s, Chu and WC to determine the quality and production of lipids and fatty acids in this diatom during exponential and stationary phases of growth. The lipid content showed significant variation between culture media i.e. 10.97, 13.98, 25.43 and 21.43% in the exponential phase and 19.09, 21.41, 19.29 and 18.54% in the stationary phase in f/2, Walne’s, Chu and WC medium, respectively. The lipid fraction of N. palea was mainly composed of myristic acid (11.76 -19.8%), pentadecanoic acid (7.76 - 18.18%), palmitic acid (3.0 - 15.1%), palmitoleic acid (3 - 15.1%), arachidonic acid (5.03 - 21.61%) and eicosapentaenoic acid (2.61 - 19.86%). Saturated fatty acids (SFAs) production was found to increase from exponential to stationary phase in all the culture media studied. Monounsaturated fatty acids (MUFAs) were found to decrease in percentage from exponential to stationary phase in f/2 and Walne’s medium whereas in Chu and WC medium MUFAs showed an increase in percentage in the stationary phase. The polyunsaturated fatty acids (PUFAs) showed a decrease in quantity as the culture entered stationary phase. The results revealed that the culture medium and the growth phase affect the quantity of fatty acids considerably and the percentage of fatty acids in each medium and growth phase are significantly different (p<0.5). In N. palea appreciable amount of saturated and unsaturated fatty acids were found which establishes the importance of this diatom in the field of aquaculture as live feed and biofuel production.
Comparative effect of High pressure and Conventional Heat Processing on the Development and Shelf life of Restructured Surimi balls during Chilled Storage
(Society of Fisheries Technologists (India), 2020) Sarika, K.; Bindu, J.; Panda, S. K.; Balange, A. K.; Gudipati, V.
There is an increasing demand towards innovative fish products to cater the demand of modern market and restructured surimi products are such emerging products. Restructured surimi balls were developed by restructuring the washed and concentrated pink perch surimi, formed into shapes under traditional heat setting at 90°C for 60 min and pressure setting at 200 MPa for 15 min. Surimi was added with MTGase (0.5%) for enhancing the crosslinking between proteins and casein as a substrate for cross linking, so as to improve the physico-chemical properties of the balls. A comparative analysis on the storage characteristics of pressure set and heat set surimi balls were done under chilled conditions. When compared with heat set balls the texture characteristics and gel strength values were less, whereas elastic nature of the product was retained in high pressure processing. High pressure can retain the raw texture of the balls with softer and glossier appearance while heat causes texture to be harder and dry. The quality indices values were found within the limit even after 16 days of storage under chilled conditions. Even though microbial quality of both samples were comparable, higher sensory score was given for pressure-set sample. Also, MTGase addition had synergistic effect with high pressure in enhancing the overall quality of products. Present study exhibited the potential of high pressure technology in developing restructured surimi balls through pressure induced gelation similar to the traditional heat induced gelation.
Effect of Chitosan Hydrogel inclusion on Centesimal Composition of Pangasius (Pangasianodon hypophthalmus) (Sauvage, 1878) Emulsion Sausages under Refrigerated Storage
(Society of Fisheries Technologists (India), 2020) Chattopadhyay, Kasturi; Xavier, K. A. Martin; Layana, P.; Balange, A. K.; Nayak, B. B.
Chitosan is a diverse polymer of biological origin having a widespread application in food industry. The cross linking properties of chitosan beneficially affects the protein-carbohydrate interactions which in turn enhances the functional properties in emulsion based meat products. In this context, the present study was conducted to incorporate chitosan hydrogel in varying ratio (0, 0.125, 0.25, 0.375 and 0.5%) into fish mince (Pangasianodon hypophthalmus) (Sauvage, 1878) sausages in order to develop a functional sausage products upon storage. Samples without chitosan additions showed a significant and rapid decline in the crude protein content after the 24th day of storage in contrast to the chitosan treated groups where a slower rate of decline was found only after 48th days of storage. Fat content also showed greater stability in the values in case of chitosan added samples upto 48th days of storage in comparison to the control samples where a rapid decrease in the contents were observed. However, ash and carbohydrate content showed minor variations among the treatment and control groups though all were showing decreasing trend upon storage. The comparative analysis of centisimal composition of the produced sausages showed that inclusion of chitosan gel had a significant effect (p<0.05) on the keeping quality of the product when compared with control and can be presumed as a superior ready-to eat quality product.
Transportation Prototype for Live Distribution of Mud Crab in Seafood Supply Chain
(Society of Fisheries Technologists (India), 2020) Parvathy, U.; Nagori, Ankur; Binsi, P. K.; Ravishankar, C. N.
A Review on the Properties and Applications of Fish Protein Hydrolysates
(Society of Fisheries Technologists (India), 2020) Parvathy, U.; Binsi, P. K.; Zynudheen, A. A.; Ninan, George
Seafood proteins have gained much attention for their nutritional richness and functionality. Peptides derived from seafoods have wide application possibilities in the form of nutritional supplements, functional food ingredients as well as improve the storage stability of food commodities facilitating superior quality products. This review presents an overview of the properties exhibited by seafood derived peptides and critically looks into the application possibilities of these derivatives in the food industry.
Studies on the Diversity and impact of Macro Biofouling Organisms in Brackish Water Finfish Cage
(Society of Fisheries Technologists (India), 2020) Sunithakumari, K.; Joseph, Shoji; Ajithkumar, P. B.; Smina, M. S.; Priya, N. P.
Biofouling refers to accumulation of organisms on submerged surfaces. In case of open water cage culture, fouling organisms attached to cage nets block water flow and reduces waste removal resulting in increased stress levels on stocked fishes and reduces the rate of intake of feed and growth. It also increases weight of the nets leading to its damage. The quantity and diversity of biofouling organisms and their effects on the growth and survival of stocked fishes were studied. The study was conducted at Moothakunnam, Ernakulam, Kerala. In the present investigation the data is of one culture period (10 months February - November 2017). The water quality parameters observed are: temperature (24.1°C to 31.7°C), Ph (6.81-7.87), salinity (0-29), light penetration (31.8 cm to 162.475 cm), DO (4.94- 10.528 mg L-1), nitrate (0.016-4.521 mg L-1), nitrite (0 to 0.954 mg L-1), orthophosphate (0.011-0.771 mg L-1) and ammonia (0 to 0.031 mg L-1). Biofouling was found initiated with filamentous algae followed by molluscs dominated by modiolus and other invertebrate organisms. Majority of the fouling organisms observed were molluscs and filamentous algae. Biofouling was highest in areas near the water surface and found reduced with depth. Almost 44.44% of the total net area was affected by biofouling. The total weight of the attachment with net was 3354.88 kg. Macrobiofoulers itself shared a total weight of 658.56 kg and modiolus (90.53%) alone contributed 588.8 kg. Apart from these associated animals like Arthropods, Annelids etc. were also found. Infestation was found increased with salinity and peaked during April-May (29 psu).

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