Genetic characterization, domestication and improvement of Macrobrachium rosenbergii in the Philippines

Extensive studies in the Philippines and in adjacent countries revealed that 528 caridean prawn species are found in this region alone (Chan, 1998). Of all the known species, the giant freshwater prawn is considered the most commercially important. Except for the Philippines, culture of the giant freshwater prawn, Macrobrachium rosenbergii, has already made substantial contributions to the local aquaculture production in Southeast Asia, i.e. in Thailand, Malaysia and Indonesia. However, efforts are now being made to improve the aquaculture production of Macrobrachium rosenbergii in the Philippines, thus, optimal methods for the culture and propagation of this high value freshwater aquaculture species are being developed by the Philippine Government fishery agencies as well as other research and academic institutions. The Integrated Rural Aquaculture Program under the ASEAN-SEAFDEC Special Five-Year Program or what is presently known as the Program on the Promotion of Sustainable Aquaculture in the ASEAN Region enabled the Bureau of Fisheries and Aquatic Resources, the Mindanao State University and the Aquaculture Department of SEAFDEC to jointly conduct studies on the genetic characterization, domestication and improvement of Macrobrachium rosenbergii stocks in the Philippines in order to improve the aquaculture production of the giant freshwater prawn. Under the collaborative project which started in late 2004, specific research activities under were conducted, and an update on their results are summarized

Freshwater prawn program of BFAR

The giant freshwater prawn (Macrobrachium rosenbengii) is one of the indigenous prawns found in many parts of the country. Locally known as ulang, it is a hardy species that is easily farmed. On the average, farmed ulang weighs from 30 to 100 grams, which translates to 10 to 25 pieces per kilo. This is very much comparable to the medium to large or jumbo sizes of brackishwater tiger shrimps or sugpo. In the wild, ulang grow as much as 500 g and sells at 300 to 350 pesos/kg ($1=P55.50), however, the quantity harvested is limited and is dependent on its seasonality. Despite the development of both hatchery and grow-out technologies for ulang, there is really no significant commercial production in the country yet, except in BFAR-operated hatcheries in Muñoz and in Dagupan. To date, the only private ulang hatchery is MBL Farms producing up to 150,000 PL or post-larvae per run (45 days), although there are entrepreneurs trained in Muñoz who are also operating small backyard hatcheries for prawns. With the emerging global market on this giant freshwater prawn coupled with improved technologies, it is but imperative to speed up the development of the industry in the country. However, the industry is faced with problems and constraints that include: • insufficient breeders • insufficient supply of post-larvae or PL for stocking • limited market supply • limited funds for interested stakeholders • insufficient information • inadequate promotion of technology transfer • very few skilled and/or trained technicians • research and development of ulang hatchery and grow-out are still wanting new technologie

Culture of giant freshwater prawn: Philippines.

Freshwater prawn thrives in inland bodies of water like rivers, lakes, swamps, irrigation canals, estuaries and even in rivers upstream. More than 100 species were reported to exist worldwide. A recent survey in Luzon Island, Philippines identified 12 species of freshwater prawn found in the island. The country’s interest on freshwater prawn fishery started in 1914 as explained by Cowles (1914), when he identified that freshwater prawn was one of the important fisheries during that time. Likewise, he discussed the geographical distribution of the species, the value of fishery and biology. In late 1976, trials were conducted to culture the freshwater prawn, however, the studies were never sustained. For these trials, the collection of wild spawners and larval rearing of M. rosenbergii was conducted in Misamis Oriental, Mindanao between 1976-1979 by Dejarme et al. Post larval stage was attained but larval rearing lasted only for 39 days. There were more attempts in the past to adopt the technology for the propagation of the species but the efforts never progressed beyond research at institution level. In 1981, a local banker-industrialist established a 100-hectare commercial Macrobrachium farm in Sta. Rosa, Nueva Ecija and a hatchery in Bulacan. Services of experts from Israel were utilized for the project. Marketable prawns were sold live in Metro Manila utilizing in-house retail outlets. After a few years, the company diversified their operations to include tilapia culture. However, even the diversification failed to save the first commercial production venture of Macrobrachium rosenbergii in the Philippines

Extension and training programs in support of tilapia farming in the Philippines

The Bureau of Fisheries and Aquatic Resources (BFAR), now a staff bureau of the Department of Agriculture (DA), is an agency mandated to look after the national development and management of the fishing industry. It constantly demonstrated its sensitivity towards the attainment of improving the lot of poor fish farmers and fishermen in the countryside. Fisheries, as a major sector of agriculture is expected to push the country s Economic Recovery Program and must be developed to realize its potential contribution. This sector contributed 4.7% at current prices to the Gross National Product (GNP) and 5.0% on constant prices in 1985. The fishing industry directly employs an estimated one million fishfarmers and fishermen. Indirectly, the industry provides employment to household members who are engaged in allied fisheries industries like fish processing, net making, boat building, ice plant and cold storage operation, fish handling, marketing and fish distribution

Replacement of fishmeal with processed meal from knife fish Chitala ornata in diets of juvenile Nile tilapia Oreochromis niloticus

A 60-day feeding trial was conducted to assess the effects of processed meal from knife fish Chitala ornata (KFM) as fishmeal replacement in diets of Nile tilapia Oreochromis niloticus juveniles. Five iso-nitrogenous (36.4% in dry matter) and isolipidic diets (8.6% in dry matter) with 0 (D1), 25 (D2), 50 (D3), 75 (D4) and 100% (D5) KFM inclusions were prepared. With a stocking density of 15 fish (0.59 ± 0.01 g) per tank, tilapia juveniles were distributed randomly in fifteen 30-L tanks. Results indicate a significant increase (P  0.05) among treatments. Results of hepatic histopathology showed absence of tumors, lesions and parenchymal inflammation in all treatments. However, mild cell membrane lysis and mild and mild to moderate apoptosis were evident in liver samples. Based on the results, KFM can partially and completely replace dietary protein from fishmeal. Moreover, D4 (75% KFM) is considered the optimal KFM replacement level for Nile tilapia juveniles

Challenges with the development and approval of pharmaceuticals for fish

With an increase in consumer recognition of the health benefits associated with seafood consumption, the volume of fisheries and aquaculture products consumed by the average American is expected to rise. With a concomitant expectation for high-quality products, aquaculture is likely to become a greater source of consumed fish. As the US aquaculture industry grows, so does the need to provide veterinary services. As with any intensive farming system, appropriate medications are needed to maintain animal health and to manage fish populations. This article introduces some of the challenges associated with drug approvals for aquatic species and describes how the process of development and regulation of drugs for use in aquatic animals differs from that associated with uses in terrestrial species