Tilapia Sex Reversal Application
March 19, 2009 by Leo 4,863 Views
Tilapias are warm water fishes originating from Africa and the Middle East that have been introduced to the Philippines for fish farming since I950. The main tilapia species cultured in ponds, cages and pens in the country is the Nile tilapia (Oreochromis niloticus). The Mozambique tilapia (Oreochromis mossambicus) and its hybrid with the Nile tilapia are grown in brackishwater ponds while the red tilapia (a hybrid of the Nile and Mozambique tilapias) is also produced in freshwater ponds and tanks to some extent are also commercially produced in the country.
A major drawback in the culture of tilapias is their ability to mature early at 2-3 months of age and breed frequently (every month at most). These characteristics cause the over-population of the stocked tilapia in ponds and the stunted growth of the fish. Moreover, with mixed-sex tilapia stocks, the sizes of the harvested fish vary from small to large because of the difference in the growth of the faster-growing males compared to the females.
For producing high yields of large-sized tilapia (I50 grams or more) in 3-4 months, all-male finger-lings are preferred by growers. To produce all-male tilapia, there are techniques that can be applied such as hand-sexing (separating the males and females manually), hybridization (mating of two species to produce all-male offspring) and artificial sex reversal. The most efficient and least expensive method is sex reversal.
This guide shall discuss the application of artificial sex reversal in tilapia for the production of high yields of large-sized fish.
What is artificial sex reversal?
Artificial sex reversal in fishes like tilapia is the process by which the physical sex direction (male or female) can be manipulated through the feeding of synthetic sex hormones (e.g., methyltestosterone) prior to and during the “sexless stage” of the fry. The technique was first developed in Japan in the 1950s for sex reversal of the aquarium fish (Oryzias medakd) and the common carp (Cyprinus carpio) and was first demonstrated to be commercially feasible for sex reversal of the Mozambique tilapia in the Philippines in the 1970s. Sex reversal of tilapias is now applied worldwide.
How artificial sex reversal is applied in tilapia?
There are three basic steps in the application of artificial sex reversal in tilapia:
- the production of fry for treatment,
- the sex reversal treatment of the fry, and
- the culture of the treated fish.
Production of Fry
To produce the right age of the tilapia fry for sex reversal treatment, a hatchery/nursery system is needed. For mouth-brooding species of tilapia fry (e.g., Nile and Mozambique tilapias), the breeding of the fish can be done using concrete tanks, earthen ponds and hapas (net enclosures) suspended in tanks or ponds. Breeders (50-250 grams each) are stocked at a sex ratio of three females to one male per square meter.
After 10-12 days from stocking, the schooling (swimming in batches) fry about 9-11 millimeters (mm) in total length are collected and transferred to holding units (hapas and tanks) for conditioning and sorting (removal of extra large fry) in a day or two before sex reversal treatment. It is essential that the fry be not more than 12 days old from hatching or more than 12 mm in length prior to treatment for effectiveness.
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2009 · All Rights Reversed ·
hi gud day..im alfie of Bohol..can u plz send me a copy/manual on sex reverse in tilapia..ung detailed po pano siya gawin and pls send..alfie_ocba@yahoo.com..
salamat po..
d2 po ako sa caloocan nakatira, pero sa capas, tarlac po ako mag aalaga ng tilapia. thanks email me at albert_diwa@yahoo.com
saan ba magandang mag seminar sa tilapia raising. salamat. email me at albert_diwa@yahoo.com. thanks!
It would be helpful to us here in Dinagat Islands if you can show us the technology of SRT for tilapia. You can text me at 09194295063. Waiting for your reple. Tnx.
Please look at the comments below with my name. I just detailed the entire procedure. E-mail me if you have further questions.
JOM
will you teach me how to make a homemade wine pls.
@evelynpatagan, check the following links:
http://www.mixph.com/2007/02/making-wine-from-fruits.html
http://www.mixph.com/2006/06/banana-chips-pastillas-wine-sauce-vinegar-figs.html
hi
musta na kayo>>>
musta na mga alaga nyong isda>>>
santoryo
thanks for the information that you sent me Leo, I really appreciate it.hopefully I can make that trip to pinas in the future.
Steven
Hi Leo I’am Steven and I’am from Southern California,just recently i read tilapia hatchery and intensive tilapia in tank in your site. my question is , is it possible for me to learn how to do artificial tilapia hatchery in small tank without any knowledge at all. if possible is there any guide books or video na pwede kong bilhin. thanks
Steven
@Steven, you can buy instructional materials (in print and video) everything about tilapia raising. it is available at TRC (632) 727-6205 and Marid Digest (632) 373-4446. Maybe you can instruct them to send it by courier. But if you’re really serious about this project, its better to attend seminar for actual hands-on and field visits (here in the Pinas).
Hi! tanong ko lng kung may topic kung pano magparami ng or magproduce ng hito fry
chris>>>
hello
musta ok na yon 5 years kana sa ganitong business.
ano ba pwede mong ipayo sa mga tulad kung gustong mag alaga nang tilapia>>>
thamks,
email me at santoryo_onepice@yahoo.com
santoryo
Sex Reversal:
I am really excited in coming across this “Sex Reversal” in talapia. Where can I learn more …any published literature, video and etc. that I can educate myself.
I am from Rota, Commonwealth of the Northern Mariana Islands (Guam, Saipan, Rota, Tinian, etc.)
I am currently raising tilapia for 5 years now and…it is pretty slow to come to market size.
thank you,
chris
Hi Chris:
I am from the Philippines.
1. The hormone used is 17a methyl testorerone. There is an aquaculture grade for this in aquaculture shops. But the best source is the drugstore. You may buy it at brand names of Proviron, Oretom M or some other brands. The generic name is “methesterone”
2. The inclusion rate is 40mg/kg fry mash.
If you are using Proviron, it comes in 25 mg. Tablet. thus, the dosage becomes 2 tabs of proviron/1.2 kg of fry mash. (You should use the most palatable mash in the market)
3. Dissolve proviron in about 50 ml of commercial Ethyl alcohol and mix it thoroughly with your feed. (You may also use gin, but in my farm, I always run out of stock of gin)
4. Air dry (not sun dry) for 3 hours or overnight.
5. Feed your fry ad libitum, 6 times a day for 21 days. They should be all male after 21 days.
Note: To ensure high reversal rate. You should use fry that are less than 10 days old (from yolk stage). The technique is collect fry for 9 days (treat this as one batch) and Feed them all together at the same time. .
Your fry should have no other food except the feed containing the hormone for obvious reasons. A tank will be useful for this purpose.
Good luck. I hope i was of help
JOM
By the way, you may email me directly at djomari@ymail.com
leo>>>
may i know kung san murang bilihan ng similya ng tilapia>>
thanks>>>
@santoryo, check mo yung “Related Posts” about tilapia raising, marami dun suppliers na naka-lista.
leo>>
ok thanks
matagal kana bang pag business nang ganito
ano ba business mo
santoryo
hi
tanong ko lang kung maganda bang business ang tilapia at kung san nakakabili nang similya nito/at ano ang pinapakain sa mga ito
email me at santoryo_onepiece@yahoo.com
thanks
santoryo
@santoryo, basahin mo lang yung “Related Posts” at malalaman mo lahat.