Aquaponic and biofloc systems have advantages when compared to conventional food production, but studies that associate both systems are incipient. The aim of this study was to evaluate the development of Lactuca sativa in hydroponic and aquaponic systems (with Rhamdia quelen) with or without bioflocs and using minimal infrastructure. Hydroponic (H-system), aquaponic (Aqua), and aquaponics with bioflocs (Aqua-BF) were evaluated in a randomized design. It did not use a greenhouse, and a single tank to produce vegetables and fish together was used. The stocking density of lettuce was 20 plants m-2. A total of 168 R. quelen juveniles were used to Aqua and Aqua-BF. Total ammonia, nitrite, and turbidity of the water were higher to Aqua-BF than H-system and Aqua. Lettuces were significantly more productive in Aqua and Aqua-BF than in H-system. There were no differences between Aqua and Aqua-BF for the parameters lettuce production and fish performance. Under the conditions of this study, it was possible to conclude that aquaponics farmers can use silver catfish, and that aquaponic systems with and without bioflocs can improve the lettuce production. The use of bioflocs in the aquaponic system may improve the productivity but needs a better study to optimize and simplify this technology.
The paper provides a short overview of Brazilian aquaculture production and some of the influences affecting its development. Data on total and species‐specific production are provided along with the locations, numbers of producers, their market contributions and influences. The focus is on some of the key groups, not all, especially tilapia, tambaqui, shrimp, prawn and mollusc farming. The wider influences on production including markets, management practices, technology, resources and research and also consumer and global influences are briefly mentioned to locate the developments in a wider context.
RESUMOUm dos maiores problemas enfrentados na aquicultura é a deterioração da qualidade da água das criações e dos ambientes receptores. Para minimizar esse problema em criações de peixes e camarões com limitada renovação de água, o uso de bioflocos pode contribuir tanto para a melhoria da qualidade da água como para a alimentação dos animais. Para verificar a possibilidade de manter bioflocos na criação de juvenis de Mugil cf. hospes (4,55 ± 0,15 g), foi realizado um experimento com três tratamentos: tainhas com inoculo de bioflocos (T), tainhas com bioflocos provenientes da criação de camarões Litopenaeus vannamei (TFC) e sem animais (SEM). O experimento teve delineamento casualizado, com três repetições e os resultados foram submetidos à análise de Kruskal-Wallis (α=0,05). Todos os tratamentos receberam ração comercial (44% PB). A concentração final de sólidos suspensos totais não diferiu (P>0,05) entre os tratamentos TFC (785,33 ± 269,05 mg L-1), T (310,67 ± 126,0 mg L-1) e SEM (298,67 ± 30,28 mg L-1), enquanto que o volume final de bioflocos de TFC (76,66 ± 5,77 mL L-1) foi maior (P<0,05) do que SEM (3,1 ± 2,48 mL L-1) e T (18,66 ± 5,50 mL L-1) foi similar a todos os tratamentos. Estes resultados demonstram que foi possível manter os bioflocos na criação de juvenis de tainhas Mugil cf. hospes, tornando possível sua criação neste tipo de sistema. PALAVRAS CHAVE: Aquacultura, bioflocos, meio heterotrófico ABSTRACT Evaluation of biofloc formation in the mullet Mugil cf. hospes rearing without water exchangeOne of the problems in aquaculture systems is the deterioration of rearing and effluent water quality. Biofloc technology (BFT) has been used both in fish and shrimp farms with limited water exchange, contributing to improve water quality and serving as complementary food source. To evaluate the formation of bioflocs in the rearing of mullet Mugil cf. hospes (juveniles of 4.55 ± 0.15 g) an experiment was conducted with three treatments: mullet with bioflocs inoculum (T); mullet with bioflocs from Litopenaeus vannamei shrimp culture (TFC) and without animals (SEM). The experiment had a randomized design with three replicates and the results were analyzed by Kruskal-Wallis (α=0.05). All treatments received commercial feed (44% CP). The final concentration of total suspended solids were similar (P>0,05) to all treatments TFC (785.33 ± 269.05 mg L-1), T (310.67 ± 126.0 mg L-1), SEM (298.67 ± 30.28 mg L-1), while of biofloc volume in TFC (76.66 ± 5.77 mL L-1) was higher (P<0.05) than in SEM (3.1 ± 2.48 mL L-1), and T (18.66 ± 5.50 mL L-1) was similar to all treatments. The results revealed that it is possible to maintain bioflocs in the culture of Mugil cf. hospes.
Aquaculture has many occupational hazards, including those that are physical, chemical, biological, ergonomic, and mechanical. The risks in aquaculture are inherent, as this activity requires particular practices. The objective of the present study was to show the risks associated with the aquaculture sector and present a critical overview on the Brazilian public policies concerning aquaculture occupational health. Methods include online research involved web searches and electronic databases including Pubmed, Google Scholar, Scielo and government databases. We conducted a careful revision of Brazilian labor laws related to occupational health and safety, rural workers, and aquaculture. The results and conclusion support the idea that aquaculture requires specific and well-established industry programs and policies, especially in developing countries. Aquaculture still lacks scientific research, strategies, laws, and public policies to boost the sector with regard to occupational health and safety. The establishment of a safe workplace in aquaculture in developing countries remains a challenge for all involved in employer-employee relationships.
Effects of ultraviolet radiation (UV) on probiotic bacteria (Bacillus subtilis and B. licheniformis) were tested in two experiments, with the following treatments: (i) UV treatmentusing fluorescent and UV-lamps and (ii) Control -CTRL, using fluorescent lamps. Bacterial abundance and respiration were evaluated every 24 h for 3 days for Experiment 1, and at 0, 6 and 24 h for Experiment 2. In the Experiment 1, total UV dose was 4 336.41 mW cm À2 . UV treatment presented small respiration rates only on day 3, while in the CTRL oxygen consumption was always high. On all days, the abundance of the Bacilli exposed to UV was significantly smaller than that of the CTRL. The second experiment, with total UV dose of 1 445.47 mW cm À2 , presented oxygen consumption in the UV treatment only during the first 6 h. In the CTRL, oxygen consumption increased from the beginning due to the bigger abundance Bacilli cells. Small coccus-shaped bacteria ocurred in the UV treatment of both experiments. It may be concluded that exposure to UV, normally used for water disinfection, can inactivate probiotic bacteria.
Latin America and the Caribbean have an important role in the world production of aquatic animals. The region is among the most productive of regions, and apart from Asia and China, it occupies major position in terms of volume, with growth prospects of 33% in the next 10 years. Chile, with Brazil and Ecuador, accounted for 77% of the South America volume production. Together with Mexico and Peru, these countries contribute 87% of LAC's aquaculture production. We reviewed the main official documents and articles related to LAC's aquaculture production. Some production data are updated, others are not. Although the region has an important role in the production of food from aquatic animals, many challenges are faced in these countries.
The eugenol is the active ingredient of clove oil and it has shown to be effective and safe as fish anesthetic. In this study were evaluated the effects of different concentrations of eugenol for anesthesia, recovery time, blood glucose and hematocrit percentage of pearl cichlid (Geophagus brasiliensis) juveniles. Concentrations of 50, 80, 100, 120, 150, 170 and 200 mg L -1 eugenol were evaluated in terms of time to achieve the different stages of anesthesia and recovery in a completely randomized design (CRD) with 12 repetitions. These results were tested using the Kruskal-Wallis test with subsequent Dunn test. The evaluated concentrations had anesthetic action of the deep induction 172.57 ± 25 s (50 mg L -1 ) and the period of full recovery of 516.25 ± 102 s (200 mg L -1 ), with statistical difference between the treatments at all the stages. The eugenol effect on blood glucose and on hematocrit percentage at 0 h after deep anesthesia was evaluated for concentrations of 0; 50; 80; 100; 150; 200 mg L -1 , in a completely randomized design with five replications, and the results were assessed by One-Way ANOVA. Glucose and percentage of hematocrit: no statistically significant differences (P>0.05) were observed for these variables. All concentrations of eugenol showed to be effective as an anesthetic for G. brasiliensis and did not affect the survival, blood glucose and the percentage of hematocrit. To minimize adverse effects and achieve faster recovery is indicate the use of 50-80 mg L -1 of eugenol for pearl cichlid juveniles.Keywords: anesthesia; clove oil; fish; pearl cichlid UTILIZAÇÃO DE EUGENOL COMO ANESTÉSICO EM JUVENIS DE Geophagus brasiliensis RESUMOO eugenol, substância ativa do óleo de cravo, tem demonstrado ser eficiente e seguro como anestésico para peixes. Neste estudo foram avaliados os efeitos de diferentes concentrações de eugenol na anestesia, tempo de recuperação, glicemia e percentual de hematócrito de cará (Geophagus brasiliensis). Concentrações de 50, 80, 100, 120, 150, 170 e 200 mg L -1 de eugenol foram avaliadas em relação aos tempos para atingir os diferentes estágios de anestesia e de recuperação, em desenho inteiramente casualizado (DIC), com 12 repetições. Os resultados foram analisados pelos testes de Kruskal-Wallis e teste Dunn. As concentrações avaliadas produziram ação anestésica em período de indução profunda de 172,57 ± 25 s (50 mg L -1 ) e no período de total recuperação de 516,25 ± 102 s (200 mg L -1 ), com diferença estatística entre os tratamentos para todas as fases avaliadas. Foi avaliado o efeito do eugenol sobre a glicose no sangue e sobre o percentual de hematócrito, em 0 h após anestesia profunda, nas concentrações 0, 50, 80, 100, 150 e 200 mg L -1 , em DIC com cinco repetições, e os resultados avaliados através de ANOVA uma via. Não foram observadas diferenças estatísticas significativas (P>0,05) para glicose e hematócrito. Todas as concentrações de eugenol avaliadas apresentaram eficiência como anestésico para G. brasiliensis e não afetaram a sobrevivência,...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.