Morphometric comparison of the growth curve in Nile tilapia (Oreochromis niloticus) sexually reverted to masculinized and feminized

Aquaculture is an industry in development around the world that allows covering the nutritional demand with a high nutritional value. Within this industry, monosex crops of some species, such as the Nile tilapia (Oreochromis niloticus), stand out. In this study, the effect of the administration of 17α-ethinyl estradiol and 17α-methyltestosterone on the morphometry of Nile tilapia at different times was evaluated. Nile tilapia were raised under controlled conditions and divided into three groups: control: no hormone treatment; feminized: treated with 17α-ethynyl estradiol and masculinized: treated with 17α-methyltestosterone. The measurements were made at 5, 10, 15, 25, 35, 40, 50, 60 and 70 days after fertilization with the morphometric technique “truss protocol.” The data were analyzed using a general linear model of repeated measurements and analysis of variance of comparison of means. The growth curve was made using the Gompertz logistic model. The results showed that the masculinized larva presented a higher growth rate and increased daily gain of weight 2.05-2 mg compared to the controls and feminized 1.67-3 mg and 7.57-4 mg, respectively. The sexual reversion of Nile tilapia with 17 α-methyltestosterone increases the growth curve of the masculinized organism and the uniformity of the final size.

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Characterization of Francisella noatunensis subsp. orientalis isolated from Nile tilapia Oreochromis niloticus farmed in Lake Yojoa, Honduras

Diseases of Aquatic Organisms ◽

10.3354/dao03333 ◽

2019 ◽

Vol 133 (2) ◽

pp. 141-145 ◽

Cited By ~ 2

Author(s):

E Soto ◽

K Shahin ◽

JJ Talhami ◽

MJ Griffin ◽

A Adams ◽

...

Keyword(s):

Oreochromis Niloticus ◽

Nile Tilapia ◽

Nile Tilapia Oreochromis Niloticus

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The effect of vaccination in controling bacterial disease caused by Aeromonas hydrophila in nile tilapia (Oreochromis niloticus)

AQUATIC SCIENCE & MANAGEMENT ◽

10.35800/jasm.0.0.2014.7302 ◽

2014 ◽

pp. 27

Author(s):

Arne A Ratulangi ◽

Reiny Tumbol ◽

Hengky Manoppo ◽

Henneke Pangkey

Keyword(s):

Survival Rate ◽

Aeromonas Hydrophila ◽

Oreochromis Niloticus ◽

Nile Tilapia ◽

Bacterial Disease ◽

Immersion Method ◽

Nile Tilapia Oreochromis Niloticus ◽

Different Ages ◽

Motile Aeromonas Septicaemia

This study aims to apply vaccination against bacterial disease. The purpose of vaccination is to trigger the immune respone both non-specific and specific of fish against bacteria Motile Aeromonas Septicaemia (MAS) caused by Aeromonas hydrophila. The vaccination for fish with different ages: 2-3 weeks and 5 weeks were done using immersion method. The fish were re-vaccinated (booster) after two weeks of the first vaccination. The survival rate was < 50 % for juveniles 2-3 weeks and > 50% for juveniles 5 weeks. Survival rate for juveniles 5 weeks was higher than juveniles of 2-3 weeks. This shows that organs of juveniles of 5 weeks were more complete than the 2-3 weeks juveniles. The age of fish is one of the important factors for successfully vaccination. Penelitian ini bertujuan untuk melakukan penerapan vaksinasi terhadap penyakit bakterial. Vaksinasi ditujukan untuk merangsang respon kekebalan non- spesifik dan spesifik pada tubuh ikan terhadap penyakit Motile Aeromonas Septicaemia (MAS) yang disebabkan oleh bakteri Aeromonas hydrophila. Vaksin diberikan pada benih ikan nila yang berbeda umur yaitu 2-3 minggu dan 5 minggu dengan menggunakan metode perendaman. Ikan divaksinasi ulang (booster) setelah 2 (dua) minggu dari vaksinasi yang pertama. Prosentase kelangsungan hidup < 50 % untuk benih umur 2-3 minggu dan > 50% untuk benih umur 5 minggu. Jumlah kematian benih umur 2-3 minggu lebih tinggi dari 5 minggu. Hal ini menunjukkan bahwa fungsi organ benih umur 5 minggu telah lebih lengkap dari pada benih umur 2-3 minggu. Umur ikan merupakan salah satu faktor penting penentu keberhasilan suatu kegiatan vaksinasi.

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