scholarly journals Evaluation of the performance of two strains of Nile tilapia (Oreochromis Niloticus) in mixed raising systems

2008 ◽  
Vol 51 (3) ◽  
pp. 531-538 ◽  
Author(s):  
Patrícia Ribeiro Neves ◽  
Ricardo Pereira Ribeiro ◽  
Lauro Vargas ◽  
Maria Raquel Marçal Natali ◽  
Káttia Regina Maehana ◽  
...  

The aim of this study was to evaluate the productive performance of two strains of Nile tilapia (Oreochromis niloticus) in mixed raising systems. A total of 3600 fish-larvae species was used, 1800 belonging to Bouaké lineage, and 1800 to Chitralada. The experiment was carried out in three phases; Phase I in an incubator in 18 boxes, in which two treatments (Bouaké and Chitralada) were tested by using nine repetitions; Phases II and III were performed in 18 cement tanks with the same treatments. In phase I, regarding the final weight and gain of weight, Chitralada strain showed the highest final weight values. In phase II, Chitralada showed the highest final weight value when compared with Bouaké, and, considering the gain of weight, Bouaké obtained the best result. In phase III, Chitralada showed better final weight results (104 days of raising), final weight, final length and gain of length/cm (152 days of raising); but, after 279 days of the cultivation, Bouaké showed a higher weight and length gain. These findings showed that Chitralada strain presented the best performance.

2012 ◽  
Vol 64 (1) ◽  
pp. 192-197 ◽  
Author(s):  
R.M.R. Sousa ◽  
C.A. Agostinho ◽  
F.A. Oliveira ◽  
D. Argentim ◽  
P.K. Novelli ◽  
...  

The performance of Nile tilapia (Oreochromis niloticus) raised in cages furnished with an automatic dispenser, supplied at different frequencies (once per hour and once every two hours) and periods (daytime, nighttime and both) was evaluated. Eighteen 1.0m³ cages were placed into a 2000m² pond, two meters deep with a 5% water exchange. One hundred and seventy tilapias, with initial weight of 16.0±4.9g, were dispersed into each 1m³ cage and the feed ration was adjusted every 21 days with biometry. Data was collected from March to July (autumn and winter). Significant difference to final weight (P<0.05) among treatments was observed. The increase in feeding frequency improves the productive performance of Nile tilapias in cages and permitted better management of the food. The better feed conversion rate for high feeding frequency (24 times day-1) can result in saving up to 360kg of food for each ton of fish produced, increasing the economic sustenance for tilapia culture and suggesting less environmental pollution.


Author(s):  
Arne A Ratulangi ◽  
Reiny Tumbol ◽  
Hengky Manoppo ◽  
Henneke Pangkey

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.


2013 ◽  
Vol 37 (10) ◽  
pp. 1460 ◽  
Author(s):  
Huaping ZHU ◽  
Maixin LU ◽  
Zhanghan HUANG ◽  
Fengying GAO ◽  
Xiaoli KE ◽  
...  

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