Tag Archive: sex reversal

Aug 16 2016

Applications of genetics in aquaculture (Updated 2016 version)

  This lecture has been delivered by Dr. Abdel Rahman El Gamal during August 2016 as a contribution to the “Fish Culture Development training course – Africa” which is annually organized by the Egyptian International Centre for Agriculture (EICA) with the support by Japan International Cooperation Agency (JICA). The introductory part of the lecture addressed …

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Permanent link to this article: http://fishconsult.org/?p=13469

Jan 27 2015

Hormonal sex reversal of tilapia fry (practice and contradicting opinions) – Video

After a short introduction of tilapia in aquaculture, this 17-min video focuses on the production of all-male tilapia through the sex reversal practices using male hormone. The logic sequence of the sex reversal process has been maintained to large extent starting by the sexual differentiation in tilapia then determining the appropriate age and/size for successful …

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Permanent link to this article: http://fishconsult.org/?p=12261

Aug 30 2014

Large-scale Chinese tilapia hatchery and the marketing of GIFT strain

Photo credit:Kevin Fitzsimmons (USA) Review: Abdel Rahman El Gamal (Founder of the website) The photo shows a part of a tilapia hatchery facility located in Hainan Province, China. Based on various information sources, the production capacity of the said hatchery is about 400 million of sex reversed tilapia fingerlings per year. This contribution to the …

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Permanent link to this article: http://fishconsult.org/?p=11621

Jun 09 2014

تفريخ البلطى النيلى وإنتاج الذكور فى أحد المفرخات فى الفلبين

Credit: Ahmed Zaki (Egypt) هذة الصورتم أخذها فى أحد مفرخات البلطى فى الفلبين وحيث يتم فى هذا المفرخ تخزين أمهات البلطى النيلى بمعدل 3 إنات لكل ذكر. يتم تجميع الزريعة السابحة من على أجناب الحوض وذلك لنقلها إلى المعاملة بالهورمون الذكرى 17α-Methyltestosterone بهدف إنتاج زريعة بلطى نيلى جميعها ذكور. يصل معدل تجميع الزريعة فى هذا …

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Permanent link to this article: http://fishconsult.org/?p=10951

Jun 09 2014

Spawning and sex reversal of Nile tilapia fry in a Pilipino hatchery

Credit: Ahmed Zaki (Egypt) The photos were taken in a tilapia hatchery in the Philippine. In this hatchery the broodstock of Nile tilapia, Oreochromis niloticus at the ratio of 3 females: 1 male. The swim-up tilapia fry are collected along the pond sides using a long-handled, narrow-mesh deep nets.  The collected fry are transferred into …

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Permanent link to this article: http://fishconsult.org/?p=10947

Jan 30 2014

Sex reversal of tilapia fry using male hormone in Benin

Credit: Ismael Radwan (Egypt) The male hormone (17 alpha- methyl testosterone)  is dissolved in alcohol at the dose of 60 milligram per 500 ml of alcohol and then after the alcohol containing hormone is to be mixed with one kg of fry feed. Treated feed is dried in shade and could be stored in freezer …

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Permanent link to this article: http://fishconsult.org/?p=10318

Jan 17 2014

Grading of tilapia fry prior to hormonal sex reversal treatment in Benin

Credit: Ismael Radwan (Egypt) As established, the effectiveness of sex reversal process depends on several factors including the initial size (age) of treated fry. If the tilapia spawning and collection systems of the fry cannot guarantee the optimum size (age) of tilapia fry, a grading system will be required. The photo shows a simple grader …

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Permanent link to this article: http://fishconsult.org/?p=10277

Oct 15 2013

Production of all-male Nile tilapia (Oreochromis niloticus) through sex reversal in Guatemala

Credit: Manuel Cano Alfaro (Guatemala) The first photo shows people collecting the swim-up fry of Nile tilapia (Oreochromis niloticus) from the spawning tanks. Tilapia broodstock are stocked at the ratio of four females for each male. The collected fry are passed to the sex reversal unit which is shown in the second photo. The sex reversal …

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Permanent link to this article: http://fishconsult.org/?p=9549

Jul 07 2013

Sex reversal in fishes (rationality – masculinization – feminization – applications)

[gview file=”http://fishconsult.org/wp-content/uploads/2013/07/Sex-reversal-in-fish.pdf”]

Permanent link to this article: http://fishconsult.org/?p=8218

Nov 20 2012

Applications of squash technique in sex determination in fish

This 2-slide bite presents the squash technique and its use in sex determination in fish. Examples are given such as sex reversal and progeny testing in tilapia. The same is true in situations whereas the sex of juvenile fish of more  species cannot be determined based on fish morphology. The bite also includes the procedures …

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Permanent link to this article: http://fishconsult.org/?p=7428

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