Saturday, January 9, 2016

Triploid Tilapia

Triploid fish are those which are sterile with three sets of chromosomes and as such will never be able to reproduce. So why would we want these sterile fish and how do we get them?

The use of hormones and antibiotics in food has skyrocketed. Not only does this have a cumulative effect on humans as we eat the meat  but also on marine life as it is eliminated and flushed out of our system into the sewers and eventually ending up in the world's oceans. We of course eat the seafood and have another dose of hormones and unwanted chemical cocktails by doing so.

So what's the answer? It could be triploid fish as this is already being seen in trout and other fish as a viable method of population control in by the US. I feel our role as  farmers is not to add to this problem but to try and eliminate  hormones from the cycle of tilapia farming if possible.

Although the treatment of hormones with 17 alpha-methyltestosterone is commonly used here in Brazil there are alternatives.  The use of cold and/or heat shock and  pressure treatment on fertilized eggs can leave the fish sterile.  This is achieved by applying  the  pressure, heat and then cold to the eggs shortly after they have been fertilized. The amount of pressure, and time held during the  heating  and chilling period are crucial to get the triploid tilapia. Too much of any of those processes and the eggs will die , not enough and it is likely to be ineffectual.

Beside saving hormones from entering the food chain, producing triploid fish is safer for the environment, as tilapia if they escape into rivers and lakes, can be an invasive species. Their rapid breeding can soon get out of hand and cause problems in many bodies of water.

It is down to tilapia farmers  to seek out alternatives and find   breeders who  are not  using hormones as a method of sex reversal.