gaa fard mar12

8/11/2019 GAA Fard Mar12

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8/11/2019 GAA Fard Mar12

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67global aquaculture advocate March/April 2012

products. In fish farming, 40 to 50% of theproduction cost is associated with feed. Toenhance the development of commercialMalaysian mahseer aquaculture, feedingthe fish an optimized diet that meets theirnutritional requirements is criticallyimportant. Knowledge of the essentialnutrients, their sources and effects on thephysiological aspects of target species iscrucial to produce an optimized diet.

 The major essential macronutrients areprotein, lipid and carbohydrate. In 2008,Ng Wing Keong and co-workers providedthe first published information on thenutrient requirements of Malaysian mah-seers. They recommended a dietary pro-tein content of 48% with a protein:energyratio of about 26 mg protein/kJ grossenergy for the best fish growth.

However, according to their results,there was no significant difference amongthe growth performances of fish feddietary protein levels from 35 to 50%. In2011, Josephine Dorin Misieng and co-

 workers also showed that a dietary pro-tein content of 40% met the proteinrequirements of this fish.

Lipids act as the main energy sourcein diets, supplying about two times moreenergy than protein and carbohydrate do.In some fish, lipids can be utilized tospare dietary protein for growth purposes.Consumption of protein as an energysource, which results from inadequateamounts of dietary lipid, can lead to pro-tein deficiency for fish growth.

In addition, lipids are an important

source of essential fatty acids, phospho-lipids and fat-soluble vitamins. There-fore, lipid was the second quantitativenutrient requirement determined.

 According to recent studies, it is clearthat 5% dietary lipid is sufficient to pro-

 vide the maximum growth of this species. The authors are currently studying

the dietary fatty acid requirements ofMalaysian mahseers to aid nutritionalknowledge, the main bottleneck in theirsuccessful propagation.

Mahseer fingerlings are mainlyproduced by two government hatcheries.Ongoing nutrition studies areimproving their growth performance.