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Macrobrachium, locally called ulang, pahe or kising-kising, is an indigenous species in the Philippines. The species cultured in Malaysia and Thailand turns out to be have been erroneously identified as M. rosenbergii but should actually have been referred to as M. dacquetti. Females can reach up to 25 cm while males can grow up to 32 cm, excluding their impressive claws. Blue-clawed males are considered dominant that they may inhibit the growth and development of both male (smaller size) and female freshwater prawn (Fishsite, 2019).

According to Dr. Westly Rosario of the BFAR National Integrated Fisheries Technology Development Center (NFTDC) in Binloc-Bonuan, Dagupan city, freshwater prawns may be cultured in 1,500 to 2,000 sq. m rectangular earthen ponds with a depth of 0.5 to 1 m. The ideal size for stocking is PL18, when they are already strong enough to resist handling and transport stress. Stocking density may range from 2-5 pieces per sq. meter. Freshwater prawns are considered omnivorous, they can feed on algae, small mollusk, crustaceans, cassava, trash fish and commercial diets. However they show cannibalistic behavior during molting period. There are two feeding techniques adapted in freshwater prawn culture. In low stocking density culture, it can be fed with natural food and then after 60 days supplemental diets such as ipil-ipil leaves or commercial feeds may be introduced. High stocking density culture usually utilizes commercial feeds (30-35% protein) and most of the feed ration are given during afternoon since they are nocturnal animals. After 4 months in a well-managed farm, 40 g individuals can be selectively harvested. Well-fed stocks in a brackishwater pond can obtain sizes ranging from 90-100 in seven months. Survival rate of stocks can range from 50-80% if well managed.

Freshwater prawns may also be raised in polyculture alongside freshwater fishes such as tilapia and carp. There is a recent development to produce monosex freshwater prawn, either all-male or all-female batches. All-female produced were injected with suspended hypertrophied androgenic gland cells at young stage. It showed better performance than mixed batches in terms of survival rate, FCR and yield size. On the other hand, gene silencing is used to induce female shrimp to produce all-male offsprings. This could shorten production time and improve productivity of culture since male shrimps will just focus on feeding rather fighting especially during mating season in a mixed-sex population (Fishsite, 2019).

Freshwater prawns are highly marketable due to their size but it loses out to penaeid shrimps in the international market due to the large head (when marketed whole) and the relative difficulty in producing them in large volumes required for export. In the Philippines, a market can potentially be developed as long as production can be made consistent. Large scale production locally is hindered by the lack of seed stock since so far the fry or juveniles can be obtained only from institutions (BFAR and SEAFDEC). The small scale production makes the fry expensive. Attempts by the private sector in the past to establish a commercial hatchery has not been sustained.

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