Limnoperna fortunei colonization and macrofouling on net cages in a subtropical reservoir (Brazil)

2021 ◽  
Author(s):  
Daercy Maria Monteiro de Rezende Ayroza ◽  
Taissa Juliana Melo ◽  
Lilian Paula Faria‐Pereira ◽  
Maria Letizia Petesse ◽  
Mauro de Freitas Rebelo ◽  
...  
2019 ◽  
Vol 64 (9) ◽  
pp. 1593-1602
Author(s):  
Daercy Maria Monteiro de Rezende Ayroza ◽  
Clovis Ferreira do Carmo ◽  
Antonio Fernando Monteiro Camargo ◽  
Márcia Divina Oliveira ◽  
Maria Letizia Petesse

2016 ◽  
Vol 5 (2) ◽  
pp. 277
Author(s):  
Usman Usman ◽  
Neltje Nobertine Palinggi ◽  
Kamaruddin Kamaruddin ◽  
Makmur Makmur ◽  
Rachmansyah Rachmansyah

Penelitian ini dilakukan untuk mendapatkan informasi tentang kebutuhan optimum kadar protein dan lemak pakan terhadap pertumbuhan dan komposisi badan ikan kerapu macan ukuran konsumsi. Sembilan pakan uji dibuat dalam bentuk moist pelet dengan tiga dosis protein (46%, 49%, dan 52%) dan tiga dosis lemak (9%, 11%, dan 13%). Ikan uji dipelihara dalam 27 keramba jaring apung ukuran 1 m x 1 m x 2 m selama 140 hari, diberi pakan uji secara satiasi dua kali sehari dan diset dalam rancangan acak kelompok pola faktorial berdasarkan kelompok ukuran bobot awal ikan yaitu (i) 122,0±4,2 g; (ii) 144,0±7,1 g; dan (iii) 172,9±10,5 g. Hasil penelitian menunjukkan bahwa laju pertumbuhan spesifik dan sintasan ikan relatif sama (>0,05) di antara perlakuan. Efisiensi pakan cenderung meningkat dengan meningkatnya kadar protein dan lemak pakan. Tingkat efisiensi pemanfaatan protein cenderung menurun dengan meningkatnya kadar protein pakan, tetapi meningkat dengan meningkatnya kadar lemak pakan. Hasil analisis proksimat badan ikan menunjukkan bahwa kadar bahan kering dan lemak ikan relatif tidak dipengaruhi (P>0,05) oleh peningkatan kadar protein pakan, namun kadar bahan kering dan lemak ikan tersebut sedikit naik dengan meningkatnya kadar lemak pakan. Kadar protein dan abu ikan relatif tidak dipengaruhi oleh perubahan kadar protein dan lemak pakan. Berdasarkan hasil penelitian ini tampak bahwa pakan dengan kadar protein 49% dan lemak sekitar 11% mampu memberikan pertumbuhan dan komposisi badan ikan kerapu macan yang baik.This experiment was conducted to investigate the optimum dietary protein and lipid level for growth and body composition of tiger grouper. Nine dietary experiments were formulated to moist pellet contain three levels of protein (46%, 49%, and 52%) and three levels of lipid (9%, 11%, and 13%). The fish were fed twice daily to satiation for 140 days in twenty seven net cages of 1 m x 1 m x 2 m, were set up factorial randomized block design based on fish size group i.e. (i) 122.0±4.2 g, (ii) 144.0±7.1 g, and (iii) 172.9±10.5 g. The results shown that specific growth rate and survival rate were not significant different (P>0.05) for all treatments. Feed efficiency increased when protein and lipid content increased. Protein efficiency decreased when protein diets increased and increased when lipid diets increased. No interaction occurred between protein and lipid content to all observable biological variables. Dry matter and lipid content of test fish were not affected by protein diets increase but by lipid diet content. Protein and ash of test fish were not affected by either protein or lipid contained in diet. To assure high growth rates and high quality of fish product, it is suggested to feed tiger grouper with diet containing 49% protein and 11% lipid. 


2016 ◽  
Vol 72 (6) ◽  
Author(s):  
A. A. Ortega-Salas ◽  
C. Angel Pereza ◽  
O. Lopez Ramos
Keyword(s):  

Hydrobiologia ◽  
2021 ◽  
Vol 848 (9) ◽  
pp. 2043-2053 ◽  
Author(s):  
Vanessa Ernandes de Amo ◽  
Jéssica Ernandes-Silva ◽  
Dieison André Moi ◽  
Roger Paulo Mormul

2021 ◽  
Vol 93 ◽  
pp. 102146
Author(s):  
S. Abe ◽  
T. Takagi ◽  
S. Torisawa ◽  
K. Abe ◽  
H. Habe ◽  
...  
Keyword(s):  

Author(s):  
Francine Girardello ◽  
Camila Custódio Leite ◽  
Luciana Bavaresco Touguinha ◽  
Mariana Roesch-Ely ◽  
Chrys Katielli Hoinacki da Silva ◽  
...  

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Heidi Moe Føre ◽  
Stine Wiborg Dahle ◽  
Rune H. Gaarder

This paper presents a study of traditional netting materials subjected to disinfecting chemicals during fish farming and treatment of net cages. A series of tests were performed in order to study the effect of various concentrations of disinfecting chemicals on the tensile strength of Raschel knitted Nylon netting materials. Simulated spill of diluted hydrogen peroxide (HP) to the jump fence during de-lousing did not affect the strength of the applied new and used knotless nylon netting samples. Hydrogen peroxide reacted with biofouling forming gas bubbles, but this did not result in reduced netting strength. The performed tests did not indicate any effect on netting strength from a simulated single, traditional bath disinfection as performed at service stations applying the disinfectant Aqua Des (AD) containing peracetic acid (PAA). However, increasing the AD concentration from 1 to 10% resulted in a strength reduction of 3–6%. Simulated spill of concentrated AD on the jump fence of a net with copper coating residuals resulted in a severe reduction in strength of 45%. This strength loss was probably a consequence of chemical reaction between copper and Aqua Des, and uncoated netting did not experience any loss in strength subjected to the same chemical exposure. These findings from application of AD should also apply to other PAA disinfection chemicals with trade names as, for example, Perfectoxid and Addi Aqua.


Sign in / Sign up

Export Citation Format

Share Document