Aquaculture Articles on Ongrowing Management


The "red" tilapia has become increasingly popular because its similar appearance to the marine red snapper gives it higher market value. The original red tilapias were genetic mutants. The first red tilapia produced in Taiwan in the late 1960s, was a cross between a mutant redish-orange female Mozambique tilapia and a normal male Nile tilapia. It was called the Taiwanese red tilapia. Another red strain of tilapia was developed in Florida in the 1970s by crossing a normal coloured female Zanzibar tilapia with a red-gold Mozambique tilapia. A third strain of red tilapia was developed in Israel from a mutant pink Nile tilapia crossed with wild Blue tilapia (Popma and Masser, 1999).  

Feeding is the most important task in the intensive pond production of catfish, and the person responsible for feeding should be an experienced fish culturist. In a normal situation, catfish can be seen only when they are coming up to feed, and their feeding behavior can be an important clue to general health and to other conditions in the pond. Thus, the person doing the feeding must be able to tell whether or not the fish are feeding normally. If they are not, the feeder must inform the manager that a potential problem exists.

Channel catfish (Ictalurus punctatus) raised in ponds are typically fed daily to apparent satiation to obtain maximum growth. However, under certain economic circumstances, catfish producers may feed less than daily to reduce feed cost and minimize economic losses. Robinson and Rushing (1994) compared different feeding strategies (once daily, every other day [EOD], once every third day [ETD] to satiation, and once daily to half satiation) for pond-raised channel catfish. They reported that maximum production was achieved by feeding to apparent satiation on a daily basis, but feed efficiency was improved by restricting feed. Further, they observed a 50% and 65% increase in feed consumption (on days fed) of fish fed EOD or ETD, respectively, compared with those fed daily.

From this study, and for the superiority of th 3rd treatment, it could be concluded that the fish – cum – duck integration system of production is important in producing meat duck and Nile tilapia fish under semi-intensive production system in earthen ponds. But it may gave attention to moderate stocking rate of ducks (125 - 250 duck / feddan) on fish ponds to safe water quality, particularly at low stocking rate of fish, as in the present study (16.8 thousand fry of 4 – 5 g / feddan). Artificial feeding of fish at 25% CP diet at 5 - 4% of fish biomass for 2 months, 4 - 3% for 3rd month, and 3 - 2% at the 4th month (under the integration system) realized the best results in fish growth performance, feed and nutrients utilization, total and prime fish productions with high DM content.

This research on the quality of farmed Southern Bluefin Tuna (SBT) (Thunnus maccoyii) has been focused on improving the colour shelf life of the sashimi product. Previous outcomes of our research group and supporting data from associated project groups have led to the current interest in evaluating the use of a supplementary feed for tuna farming that can be used to extend shelf life.