University of Bahia

Petrolina, Brazil

University of Bahia

Petrolina, Brazil
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Kitagawa A.T.,Federal University of Alfenas | Costa L.S.,Federal University of Lavras | Paulino R.R.,Federal University of Lavras | Luz R.K.,University of Minas Gerais | And 3 more authors.
Applied Animal Behaviour Science | Year: 2015

The aim of this study was to evaluate the rhythms of feeding and locomotor activity, the ability to synchronize to a fixed feeding time, and the influence of photoperiod on the growth parameters, feed intake and hematological parameters of a recently introduced fish in freshwater Brazilian aquaculture, Lophiosilurus alexandri. In experiment 1, six aquariums (60 fish each) had automatic feeders connected to a photoelectric cell set to 12L:12D conditions. The photoelectric cell emitted a continuous beam of infrared light, and the fish used the feeder for self-feeding for 36 days. In the second stage, to evaluate the ability to synchronize animals to food in a 12L:12D photoperiod condition, two different feeding schedules were established (12:00h and 00:00h) in a separate aquarium. All data were recorded on a computer. In experiment 2, 160 juveniles, (4.20±0.05g), were subjected to four treatments: 24h of light, T1 (24L:0D); 12h of light and 12h of dark with food provided during the day period, T2 (12L:12Da); 12h light and 12h dark with food provided during the night period, T3 (12L:12Db); and 24h dark, T4 (24D). The fish feeding was conducted using automatic feeders at fixed feeding times. The growth data calculated were weight gain, length gain, specific weight gain, feed conversion and survival. The blood parameters collected were total protein, hematocrit, glucose and cortisol. Fish kept at a photoperiod of 12L:12D showed greater locomotion (90% of total actions) and feeding activity (88% of total actions) in the dark phase. The locomotion activity was synchronized with the different times of feeding, with a peak of 160 actions at 12:00h (light phase) and a peak of 180 actions at 00:00h (dark phase). There was no difference for performance and survival. The feeding intake was improved in fish feed in 24 light condition (T1). The glucose, total protein and hematocrit showed no significant differences. Cortisol was significantly higher in T1 (mean±SE, 40±2.08ngmL-1) compared with the other treatments. In conclusion, considering the fish preference and their welfare, we suggest that they should be fed at night although they have the plasticity to adapt to other feeding schedules. © 2015 Elsevier B.V.


De Pintoa A.C.Q.,University of Brasilia | Silva G.J.N.,University of Bahia | Ferraz L.E.C.S.,Enterprise of Consultancy
Acta Horticulturae | Year: 2015

Brazil is one of the largest mango producer and exporter in the world with 1,2 million t produced from an area of 75,000 ha. Mango exports in 2011 were about 127,000 t which is approximately 11% of the total production. Recently, mango production in Brazil to supply internal and external market has showed a relevant tendency for organic and processed fruits. To comply with these demands there is a need to develop important strategies for the improvement of new and superior mango cultivars as well as technique of production management in order to attend the consumer and processing industry effectively. These techniques need to be applied to reduce pre-harvest problems such as susceptibility to disease, physiological disorders and poor flavor of current commercial cultivars. This paper suggests some efficient mango breeding strategies to develop the so called "ideal mango cultivar" and it discusses relevant production management techniques and also the environmental effects on mango production and quality as an answer to the dynamic of the internal and external market demands.


Cabanelas I.T.D.,University of Cádiz | Arbib Z.,University of Cádiz | Chinalia F.A.,University of Bahia | Souza C.O.,University of Bahia | And 4 more authors.
Applied Energy | Year: 2013

The present work aimed to evaluate the auto/mixotrophic growth of microalgae using domestic wastewater (WW) amended with glycerol aiming biofuels production. The best results were obtained with the highest glycerol supplementation (50mM). In such condition, Chlorella vulgaris and Botryococcus terribilis showed a biomass productivity of 118 and 282mgl-1d-1, which produced about 18 and 35mgl-1d-1 of lipids, respectively. Thus, if scaled-up (200m3d-1 of WW, 240 working days y-1) biomass and lipid yields may be about 5.6tonsy-1 and 894.2kgy-1 or 13.5tonsy-1 and 1.6tonsy-1 for C. vulgaris and B. terribilis, respectively. The mixotrophic production of lipids can generate high quality biodiesel according to estimations using their fatty acids profiles. The whole process can be advantageously combined with the production of other biofuels (e.g. methane and bio-ethanol) in a biorefinery scenario. This combination of algal biomass production with waste treatment (WW amended with glycerol) can have a significant impact in the water treatment sector and local markets. © 2013 Elsevier Ltd.


Santos A.D.A.,University of Bahia | Lopez-Olmeda J.F.,University of Murcia | Sanchez-Vazquez F.J.,University of Murcia | Fortes-Silva R.,University of Bahia
Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology | Year: 2016

The role of light and feeding cycles in synchronizing self-feeding and locomotor activity rhythms was studied in white shrimps using a new self-feeding system activated by photocell trigger. In experiment 1, shrimps maintained under a 12:12 h light/dark (LD) photoperiod were allowed to self-feed using feeders connected to a photoelectric cell, while locomotor activity was recorded with a second photocell. On day 30, animals were subjected to constant darkness (DD) for 12 days to check the existence of endogenous circadian rhythms. In the experiment 2, shrimps were exposed to both a 12:12 h LD photoperiod and a fixed meal schedule in the middle of the dark period (MD, 01:00 h). On day 20, shrimps were exposed to DD conditions and the same fixed feeding. On day 30, they were maintained under DD and fasted for 7 days. The results revealed that under LD, shrimps showed a clear nocturnal feeding pattern and locomotor activity (81.9% and 67.7% of total daily food-demands and locomotor activity, respectively, at nighttime). Both feeding and locomotor rhythms were endogenously driven and persisted under DD with an average period length (τ) close to 24 h (circadian) (τ = 24.18 ± 0.13 and 23.87 ± 0.14 h for locomotor and feeding, respectively). Moreover, Shrimp showed a daily food intake under LD condition (1.1 ± 0.2 g day-1 in the night phase vs. 0.2 ± 0.1 g day-1 in the light phase). Our findings might be relevant for some important shrimp aquaculture aspects, such as developing suitable feeding management on shrimp farms. © 2016 Elsevier Inc.


Cabanelas I.T.D.,University of Cádiz | Ruiz J.,University of Cádiz | Arbib Z.,University of Cádiz | Arbib Z.,AQUALIA Gestion Integral del Agua S.A. | And 5 more authors.
Bioresource Technology | Year: 2013

The streams from municipal wastewater treatment plants (WWTP) have been considered a valuable medium for mass cultivation of algal biomass. The aim of this work is to test and compare the performance of Chlorella vulgaris on several streams from five stages, from two different WWTP. The results showed biomass yields ranging from 39 to 195mg dry-weightl-1days-1. The best performance as biomass production was obtained with the centrate (effluent from drying the anaerobic sludge). After testing a wide range of N/P ratios with centrate, the highest productivity and growth rates were obtained with the original N/P ratio (2.0) of this stream. The highest removal rates were of 9.8 (N) and 3.0 (P) mgl-1days-1, in the centrate. Finally, this research also suggests that microalgal production seems to be a promising process when coupled to wastewater treatment. © 2012 Elsevier Ltd.


Cabanelas I.T.D.,Federal University of Bahia | Marques S.S.I.,Federal University of Bahia | de Souza C.O.,University of Bahia | Druzian J.I.,University of Bahia | Nascimento I.A.,Federal University of Bahia
Algal Research | Year: 2015

Botryococcus is a microalgae genus with high potential for bioenergy, but studies on Botryococcus are frequently between slow growth and high oil content. To answer questions about the energetic applications of Botryococcus we analyzed the biomass gross composition (proteins, carbohydrates, and lipids) of three Botryococcus strains at different media concentrations at laboratory scale. Kinetic parameters were also considered for the biorefinery scenario estimates. Botryococcus terribilis (IBL-C117) showed the highest lipid productivities among all three strains, ranging from 42 to 52mgL-1d-1. Botryococcus braunii UTEX LB 572 showed simultaneously the highest biomass productivity and the highest content of protein and carbohydrates when compared to the other strains. B. terribilis showed a mixed biomass composition depending on the applied treatment. Estimation based on correlative models, applied to the fatty-acid profiles, showed, for all cases, biodiesel compliance to international quality standards (EU, USA and Brazil). The best cases were for B. braunii (UTEX) and B. terribilis with biomass productivities respectively reaching 272 and 244kg per year. To refine the biomass of Botryococcus into several products/by-products could increase commercial gains. © 2015 Elsevier B.V.


da Silva R.F.,University of Bahia | Kitagawa A.,Unifenas University | Sanchez Vazquez F.J.,University of Murcia
Reviews in Fish Biology and Fisheries | Year: 2016

The principles of modern aquaculture encourage the development of fish feeds containing low fish meal content and several types of plant ingredients plus nutrients to avoid depleting global fish stocks and to reduce costs. However, food constituents can affect animal nutrition and feeding behavior, so the effect of different diets on fish behavior and growth needs to be understood to optimize the use of nutrients and to improve fish welfare. The development of multiple-choice self-feeding systems led to a new perspective for investigating these issues in aquaculture species. Our purpose with this review is to summarize the information that has been published to date on this topic and to identify gaps in knowledge where research is needed. Key subjects are assessed under the following major headings: How do we study dietary selection in fish? What food signals do fish use to choose the right diet? and How do fish respond to food challenges? The present review will provide a picture of the main results obtained to date in these studies in aquaculture fish species, as well as perspectives for future research in the field. © 2015, Springer International Publishing Switzerland.


PubMed | University of Murcia, University of Bahia and Federal University of Bahia
Type: | Journal: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology | Year: 2016

The light-dark cycle and feeding can be the most important factors acting as synchronizers of biological rhythms. In this research we aimed to evaluate synchronization to feeding schedule of daily rhythms of locomotor activity and digestive enzymes of tilapia. For that purpose, 120 tilapias (65.00.6g) were distributed in 12 tanks (10 fish per tank) and divided into two groups. One group was fed once a day at 11:00h (zeitgeber time, ZT6) (ML group) and the other group was fed at 23:00h (ZT18) (MD group). The fish were anesthetized to collect samples of blood, stomach and midgut at 4-hour intervals over a period of 24h. Fish fed at ML showed a diurnal locomotor activity (74% of the total daily activity occurring during the light phase) and synchronization to the feeding schedule, as this group showed anticipation to the feeding time. Fish fed at MD showed a disruption in the pattern of locomotor activity and became less diurnal (59%). Alkaline protease activity in the midgut showed daily rhythm with the achrophase at the beginning of the dark phase in both ML and MD groups. Acid protease and amylase did not show significant daily rhythms. Plasma glucose showed a daily rhythm with the achrophase shifted by 12h in the ML and MD groups. These results revealed that the feeding time and light cycle synchronize differently the daily rhythms of behavior, digestive physiology and plasma metabolites in the Nile tilapia, which indicate the plasticity of the circadian system and its synchronizers.


PubMed | University of Bahia and University of Murcia
Type: | Journal: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology | Year: 2016

The role of light and feeding cycles in synchronizing self-feeding and locomotor activity rhythms was studied in white shrimps using a new self-feeding system activated by photocell trigger. In experiment 1, shrimps maintained under a 12:12h light/dark (LD) photoperiod were allowed to self-feed using feeders connected to a photoelectric cell, while locomotor activity was recorded with a second photocell. On day 30, animals were subjected to constant darkness (DD) for 12days to check the existence of endogenous circadian rhythms. In the experiment 2, shrimps were exposed to both a 12:12h LD photoperiod and a fixed meal schedule in the middle of the dark period (MD, 01:00h). On day 20, shrimps were exposed to DD conditions and the same fixed feeding. On day 30, they were maintained under DD and fasted for 7days. The results revealed that under LD, shrimps showed a clear nocturnal feeding pattern and locomotor activity (81.9% and 67.7% of total daily food-demands and locomotor activity, respectively, at nighttime). Both feeding and locomotor rhythms were endogenously driven and persisted under DD with an average period length () close to 24h (circadian) (=24.180.13 and 23.870.14h for locomotor and feeding, respectively). Moreover, Shrimp showed a daily food intake under LD condition (1.10.2gday(-1) in the night phase vs. 0.20.1gday(-1) in the light phase). Our findings might be relevant for some important shrimp aquaculture aspects, such as developing suitable feeding management on shrimp farms.


PubMed | University of Bahia, University of Murcia and Federal University of Lavras
Type: | Journal: Comparative biochemistry and physiology. Toxicology & pharmacology : CBP | Year: 2016

The aim of this research was to investigate the presence of daily rhythms in the somatotropic axis of tilapia fed at two times (mid-light, ML or mid-dark, MD) and the influence of the time of day of growth hormone (GH) administration on the response of this axis. Two different GH injection times were tested: ZT 3 (3h after lights on) and ZT 15 (3h after lights off). In both experiments, the mRNA expression levels of hypothalamic pituitary adenylate cyclase-activating polypeptide (pacap), pituitary growth hormone (gh), liver insulin-like growth factors (igf1 and igf2a), and liver and muscle growth hormone receptors (ghr1 and ghr2) and IGF receptors (igf1ra and igf2r) were evaluated by means of qPCR. Daily rhythms were observed in the liver for ghr1, ghr2 and igf2r but only in fish fed at ML, with the acrophases located in the light phase (ZT 3:30, 3:31 and 7:38 h, respectively). In the muscle, ghr1 displayed a significant rhythm in both groups and ghr2 in ML fed fish (acrophases at ZT 5:29, 7:14 and 9:23h). The time of both GH administration and feeding influenced the response to GH injection: ML fed fish injected with GH at ZT 15 h showed a significant increase in liver igf1, igf2a and ghr2; and muscle ghr2 expression. This is the first report that describes the existence of daily rhythms in the somatotropic axis of tilapia and its time-dependent responses of GH administration. Our results should be considered when investigating the elements of the somatotropic axis in tilapia and GH administration.

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