Utilisation of trash fish. Pt. 1. Preparation of fish flake

The paper deals with the investigations carried out on the preparation of odorless fish-starch flakes using partially deodorized trash fish meat and different sources of starch like corn, tapioca, maida and black gram. It has been found that the products using corn and tapioca are better compared to those prepared using other two starches, the product from corn being the best. The product has a protein content of about 20% and has been found to have a storage life of 4 months at 37°c.

Utilisation of trash fish. Pt. 2. Studies on preparation of fish soup mix

The paper deals with the investigations carried out on the preparation of fish soup mix using partially deodorized trash fish meat. The product contained about 25% protein and had a storage life of 4 months at ambient temperature (28-31°C).

Utilization of trash fish for human consumption. 3: Studies on the development of fish pickle from Nemipterus japonicus

A method for the preparation of fish pickles from a lean variety of fish namely pink perch (Nemipterus japonicus) is described. Dipping the fish in 10% sodium chloride solution containing 6% acetic acid before pickling, was found desirable for retaining the meaty texture of the product. The product has no fish smell or flavour and has a shelf life of more than six months at ambient temperatures and scored very well in organoleptic tests.

Diversification in utilisation of trash fish by gamma irradiation

Radiation pasteurisation enhances the shelf stability of trash fish varieties and enables the grading of fish depending upon the freshness quality. As against the ice-chilled fish which spoils within 8-10 days, exposure to 100 Krad and storage at ice temperature helps in maintaining the quality in Grade I, II or III up to 10, 20 or 25 days respectively. The improvement in quality thus provides scope for greater utilisation of trash fish for various secondary products.

Improvement in the nutritive quality of soyabean meal by co-ensiling with under-utilized fish discards

Improvement in the nutritive value of soybean meal was investigated by Co-ensiling it with underutilized trash fish discards (gizzard shad)at different proportions. The following proportions of gizzard shad to soybean meal were used; (a) 100% gizzard shad + acid combination (b)80% gizzard shad +20% soybean meal & 10% WB (c) 60% gizzard shad + 40% soybean meal & 10% WB (d) 100% gizzard shad without acid combination. Co-ensiling was achieved by adding sufficient acid to produce a paste. Products were neutralized by addition of 2% (by weight) calcium hydroxide and drying was affected by freeze-drying.The dried silage products were stored at low temperatures. Products were analysed for proximate composition and amino acid composition.The amino acid composition and ration of essential amino acid. Non essential amino acid (EAA/NEAA) was used as index of nutritive quality. Also essential amino acid profile of the co-ensiled products were compared with essential amino acid requirement of some warmwater fish species to estimate their nutritive usefulness for these species

Small Indigenous Freshwater Fish Species: their Role in Poverty Alleviation, Food Security and Conservation of Biodiversity, 23-25 February 2010, Central Inland Fisheries Research Institute, Barrackpore, Kolkata, West Bengal. Workshop report

This is the report on the workshop on “Small Indigenous Freshwater Fish Species: Their Role in Poverty Alleviation, Food Security and Conservation of Biodiversity”, organized by the International Collective in Support of Fishworkers(ICSF) in collaboration with the Inland Fisheries Society of India (IFSI). The workshop was a forum for exchange of views on the role of small indigenous freshwater fish species (SIFFS) in enhancing rural food supply and livelihood security, and in conserving biodiversity. The workshop also discussed the socioeconomic and cultural contexts for the culture and capture of SIFFS, and how to enhance access—especially for women—to better incomes, livelihoods and nutritional security, through appropriate policy spaces. This report provides a fresh focus on SIFFS, usually regarded as ‘trash’ fish. It urges scientists, researchers and decisionmakers to develop policy and legislative measures to ensure the conservation and promotion of SIFFS, both in capture- and culture-fisheries systems. This report will be useful for fishworker organizations, researchers, policymakers, fish farmers, members of civil society and anyone interested in fisheries and livelihoods. (PDF contains 86 pages)

Development of partially hydrolysed and deodourised fish flour

A process developed for preparation of partially hydrolysed and deodorised (PHD) fish flour, without solvent extraction is described. The PHD fish flour prepared from four varieties of trash fish had creamy white colour and contained 87-92% protein and 7-8% available lysine. The products had shelf life of more than a year at room temperature, and caused no grittiness when incorporated in snacks and bakery products at 10% and 7.5% level respectively. The flour prepared from Nemipterus spp. had a PER 2.32 compared to 2.68 of raw fish meat and 2.5 of standard casein.

Towards understanding the impacts of the pet food industry on world fish and seafood supplies

The status of wild capture fisheries has induced many fisheries and conservation scientists to express concerns about the concept of using forage fish after reduction to fishmeal and fish oil, as feed for farmed animals, particularly in aquaculture. However, a very large quantity of forage fish is being also used untransformed (fresh or frozen) globally for other purposes, such as the pet food industry. So far, no attempts have been made to estimate this quantum, and have been omitted in previous fishmeal and fish oil exploitation surveys. On the basis of recently released data on the Australian importation of fresh or frozen fish for the canned cat food industry, here we show that the estimated amount of raw fishery products directly utilized by the cat food industry equates to 2.48 million metric tonnes per year. This estimate, plus the previously reported global fishmeal consumption for the production of dry pet food suggest that 13.5% of the total 39.0 million tonnes of wild caught forage fish is used for purposes other than human food production. This study attempts to bring forth information on the direct use of fresh or frozen forage fish in the pet food sector that appears to have received little attention to this date and that needs to be considered in the global debate on the ethical nature of current practices on the use of forage fish, a limited biological resource.

Use of wild fish and other aquatic organisms as feed in aquaculture; a review of practices and implications in the Asia Pacific

Global and Asian aquaculture have witnessed a ten-fold increase in production from 1980 to 2004. However, the relative percent contribution to production of each of the major commodities has remained almost unchanged. For example, the contribution of freshwater finfish has declined from 71 to 66 percent in Asia but has remained unchanged globally over the last 20 to 30 years. This fact has dictated trends in the use of fish as a feed for cultured stocks. The growth in the sector has gone hand in hand with an increasing dependence on fish as feed, either directly or indirectly. In a number of countries in the Asia-Pacific region, the aquaculture sector has surpassed the capture fisheries sector in its respective contributions to the gross domestic product (GDP). Aquaculture’s increased contribution to national GDPs can be taken as a clear indication of the contribution of the sector to food security and poverty alleviation. The use of finfish and other aquatic organisms as a feed source can be through direct utilization of whole or chopped raw fish in wet form, through fishmeal and fish oil in formulated feeds, and/or as live fish, although the latter is uncommon and the overall amounts used are relatively small. In the first two categories, the fish used are often termed “trash fish/low-value fish”. Although attempts have been made to define this term, all definitions have a certain degree of ambiguity and/or subjectivity. In this regional review, the amount of fish used as feed sources based on the above categories was estimated primarily from the production data, supported by assumptions on the inclusion levels of fishmeal in formulated feeds and observed feed conversion efficiencies for both formulated feeds and for stock fed trash fish/low-value fish directly. A scenario for the use of fish as feed was developed by starting from the levels of aquaculture production recorded in 2004 and assuming increases in production volumes of 10, 15 and 20 percent by 2010, respectively, for the three trajectories. In parallel, the pattern of wild fish use as feed was projected to change as fish and shrimp farmers increasingly replace farmmade feeds by incorporating trash fish/low-value fish with manufactured feeds that include fishmeal. Also, the fishmeal inclusion rates in manufactured feeds are falling slowly, and this has been incorporated into the projections. The regional review also deals with the production of fishmeal using trash fish/low-value fish in the Asia-Pacific region. Regional fishmeal production as a whole is relatively low when compared with that of major fishmeal-producing countries such as Chile, Iceland and Norway, amounting to approximately 1 million tonnes per year. However, there is a trend towards increasing the use of fish industry waste, such as from the tuna canning industry in Thailand. The fishmeal produced in the region is priced considerably lower than globally traded fishmeal, but its quality is poorer. Total fishmeal use in Asian aquaculture in 2004 was estimated as 2 388 million tonnes, the highest proportion of this being used for crustacean aquaculture (1 418 million tonnes). Based on growth predictions (to year 2010) in the sector and improvements to feed quality and management, it is expected that the quantity of fishmeal used in Asian aquaculture will be slightly less than at present. An estimated 240 000 tonnes of fish oil is used in Asian aquaculture, principally in shrimp feeds. Based on production estimates of commodities in 2004 that rely on trash fish/low-value fish as the main feed source, this regional review suggests that Asian aquaculture currently uses between 2 465 and 3 882 million tonnes, an amount that is predicted to decrease to between 1.890 and 2 795 million tonnes by 2010. The use of trash fish/low-value fish and fishmeal by the aquaculture sector has been repeatedly adjudicated as a non-sustainable practice, and globally the sector is seeking to reduce its dependence on fish as feed through improved feed management practices and development of better quality feeds and feed formulations using alternative ingredients. Over the next few years, decreases in the use of trash fish/low-value fish are also expected to be achieved through better conversion of raw materials into fishmeal and fish oil during the reduction processes. The “way forward” in addressing the issue of the use of fish as feed in aquaculture in the Asia-Pacific region includes the need for a concerted regional research thrust to reduce the use of fish as feed sources in aquaculture, as has been achieved in the animal husbandry sector. Secondly, there is a need to increase farmer awareness on the use of trash fish as feed. This is achievable, considering the similar progress that has been made by the region’s shrimp farming sector, which almost exclusively involves small-scale practitioners who are often clustered in a given locality. The analysis also suggests that the use of trash fish/low-value fish in aquaculture may be compatible with improving food security and alleviating poverty. In Asia, trash fish/low-value fish is mostly landed in areas where there are other suitable fish commodities for human consumption. To make the trash fish/low-value fish suitable and available for human consumption would involve some degree of value-adding and transportation costs, which are likely to increase the price to beyond the means of the consumer, particularly in remote rural areas. Under such a scenario, the direct or indirect use of this perishable resource as a feed source to produce a consumable commodity appears to make economic sense and appears to be the most logical use for overall human benefit. In this manner, trash fish/low-value fish contributes to food security by increasing income generation opportunities and hence contributes to poverty alleviation. Another factor that needs to be taken into account is the large numbers of artisanal fishers who harvest this raw material. The continued use of trash fish/low-value fish, therefore, allows these fishers to maintain their livelihoods¹. Admittedly, this is an area that warrants more detailed investigation, from resource use, livelihoods and economic viewpoints.

Effects of cowdung application on the production of mud crab (Scylla serrata Forskal) in brackishwater pond

A culture experiment of mud crab for 84 days was conducted in earthen pond at Brackishwater Station, Bangladesh Fisheries Research Institute, Paikgacha, Khulna. The aim of the experiment was to study the effects of cowdung application on crab production and water quality. There were three treatments as without cowdung (T1), 500 kg cowdung/ha/fortnight (T2) and 750 kg cowdung/ha/fortnight (T3) with three replicates for each. The result was evaluated on the basis of growth, production, survival rate etc. The experimental months were mid-April '96 to mid-July '96. To maintain a good water quality, water was exchanged in every spring tide. The range of salinity during the experiment was 8-19 ppt. Trash fish and fresh shrimp head were used as feed on raw basis in every alternate week at a rate of 8% body weight of crab at the same time rice bran and wheat flour were used at a rate of 2% body weight as a source of carbohydrate. The production of T1, T2 and T3, were 720.35 kg, 862.16 kg and 669.19 kg/ha respectively. Though the effects of cowdung on production of crab is insignificant but in terms of production, survival rate and growth, the study suggest that the application of cowdung in addition to feed can be recommended for mud crab culture at a rate of 500 kg/ha/fortnight.

The propagation of the mud crab Scylla serrata (F.) de Haan

The mud crab Scylla serrata is an important commercial species found in many brackish areas in the Philippines. During spawning and hatching, the berried females migrate to the sea. Seeds for pond stocking are obtained from the wild. Because of the unpredictability of seed supply, there is a need to propagate the species artificially. Thus, spawning, larval rearing, maturation, and rematuration of the species are being studied. The first attempts at hatching S. serrata were successful with rates varying between 75% and 90%. Two out of three trials on larval rearing yielded a few megalops. The first zoeal stages were fed diatoms, rotifers, Artemia salina, and bread yeast. Overfeeding programs were implemented during the critical premolting periods to prevent weakening of the larvae and lessen cannibalism. Larval weakening during the premolt makes them susceptible to attacks by fungi like Lagenidium and ciliates like Vorticella. S. serrata larvae survived salinity levels as low as 15 ppt until the 14th day of rearing. Other larvae were able to survive in salinities of 30-32 ppt for 8 to 13 days. Zoeal molting was hastened by lowering the salinity to 25-27 ppt. Artificial broodstocking of juveniles and adult crabs has been made possible using a simple refuge system made of three-compartmented hollow blocks. This system has been helpful in minimizing fighting among crabs. Remarkable growth rates have been observed with feeds like mussel meat and trash fish. Average growth increments of 11 mm carapace length and 20 . 35 g body weight have been observed every fortnight. A newly spent spawner could gain additional weight of 22 . 5 g in only 6 days. Feeding rates of juveniles and adult crabs have been established based on the average body weight from an experiment using mussel meat. Crabs feed more at night. In another experiment, eyestalk ablation was found to be effective in inducing growth and mating. Aside from hastening the molting process, copulation is induced even among the small crabs (average carapace length = 55 mm). Natural mating lasts about 26 hr. A copulation which lasted for seven days with a break in between was observed.

Attractants in purified diets

Juvenile Penaeus monodon were reared on purified diets containing different attractants used to gelatinize the cornstarch: plain water, shrimp, mussel, squid or trash fish extract. The highest survival rate was observed in the group given the shrimp attractant, followed by mussel, fish and squid. However growth appeared best in the diet containing mussel extract. Mussel extract apparently can be used to enhance the attractability of purified diets.

Agiis: a bivalve cultivated as live shrimp feed

Live 'agiis' have been proven to be a good feed for shrimp for the past ten years by polyculture fish farmers in the province of Capiz, in the island of Panay, west central Philippines. A brief account is given of culture and feeding operations. Its cultivation period is short and seeds are readily available. It can reduce dependence on trash fish which is now getting to be scarce; it also seems much cheaper. Perhaps this fast-growing tiny bivalve can be scientifically investigated by students of aquaculture as feed for other commercial aquaculture species. Its scientific identification can be a good start.

Pasteurelose em juvenis de cobias (Rachycentron canadum) criados em tanques-redes no litoral norte do estado de São Paulo - Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)