Enter Mr. Sipe
Fate brought me to Mr. Sipe's doorstep, and from day one I knew I wanted to know everything he knows about tilapia. I've been his student since 2005.
Mr. Sipe is an Aquaculture consultant and has been in the tilapia production, hormone-free genetic improvement, and breeding business for over 30 years.
Through a selection process I like to call "descent with modification", (which I stole from Charles Darwin), that simply means selecting the best specimens out of thousands in a generation, he has been able to produce modified tilapia gene lines with special attributes, as in improved color (red/orange females which make it foolproof to distinguish them from males), Improved Body Form (the Hornorum male in a breeder colony will produce hybrids with more usable meat), and most importantly the ability to produce at least 98% male offspring from these breeders. (An all male population is highly desired because they grow faster and bigger).
The importance of this last attribute will become evident as you browse this website. (hint: NO HORMONES OF ANY KIND ARE USED HERE!
THE HYBRID FINGERLINGS ARE NATURALLY ALL MALE!)
It has to do with the genetic make up of the pure breeds!
The female pure breed Mossambica has "XX" sex-chromosomes and the male Hornorum has "ZZ" sex-chromosomes. The result of their breeding will be "XZ" chromosome hybrids which will be 98% male.
Unfortunately, with the advent of "sex reversal hormones", the commercial Tilapia farming industry found a way to have all male populations in a less costly (for them) manner. Of course they are not the ones eating the stuff.
Thus, Large scale Tilapia hybridization fell by the wayside.