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Leal A.L.G.,Companhia Hidro Eletrica Do Sao Francisco | de Castro P.F.,Embrapa Meio Norte | de Lima J.P.V.,Instituto Agronomico Of Pernambuco Ipa | de Souza Correia E.,Federal Rural University of Pernambuco | de Souza Bezerra R.,Federal University of Pernambuco
Aquaculture International | Year: 2010

A 45-day feeding trial was carried out to evaluate the use of shrimp protein hydrolysate (SPH) in diets for Oreochromis niloticus, L. SPH was included in isonitrogenous diets replacing fish meal protein by 0, 5, 10, and 20% and offered to Nile tilapia juveniles (1.7 ± 0.4 g) stocked in 40-L glass aquaria. The inclusion of SPH produced no significant differences (P ≥ 0.05) in final weight, survival, weight gain, average daily gain, specific growth rate, feed conversion ratio, protein efficiency ratio, or apparent net protein utilization. The inclusion of SPH Nile tilapia diets significantly affected (P < 0.05) the final fish body composition. Protein and ash contents decreased and fat content increased slightly with the increase in SPH. This study has demonstrated that SPH is a promising protein feedstuff and could account for as much as 6% of Nile tilapia diets with no adverse effects on growth and nutrient utilization. © 2009 Springer Science+Business Media B.V.

Brito L.O.,Instituto Agronomico Of Pernambuco Ipa | Arantes R.,Federal University of Santa Catarina | Magnotti C.,Federal University of Santa Catarina | Derner R.,Federal University of Santa Catarina | And 3 more authors.
Aquaculture International | Year: 2014

An indoor trial was conducted for 28 days to evaluate the effects and interactions of biofloc and seaweed Ulva lactuca in water quality and growth of Pacific white shrimp Litopenaeus vannamei in intensive system. L. vannamei (4.54 ± 0.09 g) were stocked in experimental tanks at a density 132 shrimp m-2 (566 shrimp m-3) and the U. lactuca was stocked at a density 0.46 kg m-2 (2.0 kg m-3). Biofloc with seaweed (BF-S) significantly reduced (P < 0.05) total ammonia nitrogen (TAN) by 25.9 %, nitrite-nitrogen (NO2-N) by 72.8 %, phosphate (PO 4 3 -P) by 24.6 %, and total suspended solids by 12.9 % in the water and significantly increased (P < 0.05) settleable solids by 34.2 % and final weight of shrimp by 6.9 % as compared to biofloc without seaweed. The BF-S can contribute by reducing nitrogen compounds (TAN and NO2-N), phosphate (PO 4 3 -P), and total suspended solids in water and increased final weight of shrimp. © 2013 Springer Science+Business Media Dordrecht.

Brito L.O.,Instituto Agronomico Of Pernambuco Ipa | Chagas A.M.,Federal Rural University of Pernambuco | da Silva E.P.,Federal Rural University of Pernambuco | Soares R.B.,Federal Rural University of Pernambuco | And 2 more authors.
Aquaculture Research | Year: 2016

An indoor trial was conducted for 42 days to evaluate water quality, Vibrio density and growth of Litopenaeus vannamei in an integrated biofloc system (IBS) with Gracilaria birdiae. Four treatments were used, each in triplicate: Control (monoculture shrimp); IBS 2.5 (L. vannamei and 2.5 kg wet weight seaweed m-3); IBS 5.0 (L. vannamei and 5.0 kg wet weight seaweed m-3) and IBS 7.5 (L. vannamei and 7.5 wet weight seaweed m-3). Shrimp individuals (0.34 ± 0.01 g) were stocked at a density of 500 shrimp m-3. No water exchange was carried out during the experimental period. Molasses was added once a day as an organic carbon source to maintain the C:N ratio at 12:1. The IBS significantly decreased (P < 0.05) dissolved inorganic nitrogen (DIN) ranging from 19% to 34% (3.12-3.83 mg L-1), NO3-N ranging from 19% to 38% (2.40-3.16 mg L-1), Vibrio density ranging from by 8-83% (0.40-2.20 log 103 colony-forming units mL-1), and FCR ranging from by 20-30% (1.20-1.37), as compared to the control (4.73 mg L-1, 3.93 mg L-1, 2.40 log 103 colony-forming units mL-1, and 1.74 respectively). Moreover, the IBS significantly increased (P < 0.05) crude protein in whole body shrimp, ranging from 8% to 13% (13.2-13.7% wet weight basis); as well as final weight, ranging from 25% to 32% (3.90-4.12 g), weekly growth ranging from 25% to 34% (0.59-0.63 g), and shrimp yield by 22-39% (1.72-1.96 kg m-3), as compared to control (12.1% wet weight basis, 3.12 g, 0.47 g, and 1.41 kg m-3 respectively). It can thus be concluded that cultivating Gracilaria birdiae in an IBS with L. vannamei can contribute to DIN and NO3-N removal, lower Vibrio density, increased crude protein in whole body shrimp, higher growth and yield parameters in shrimp culture. © 2016 John Wiley & Sons Ltd.

Dutra K.A.,Federal Rural University of Pernambuco | de Oliveira J.V.,Federal Rural University of Pernambuco | Navarro D.M.A.F.,Federal Rural University of Pernambuco | Barbosa D.R.S.,Federal Rural University of Pernambuco | Santos J.P.O.,Instituto Agronomico Of Pernambuco Ipa
Journal of Stored Products Research | Year: 2016

The cowpea weevil, Callosobruchus maculatus (F.), is a major pest of cowpea Vigna unguiculata (L.) Walp. in storage units, making the grains unsuitable for consumption. The adverse effects of chemical control methods have been motivating the demand for alternatives in pest control, such as the use of natural products like essential oils. The aim of this study was to obtain and chemically identify the components of essential oils extracted from fruit peels of Citrus latifolia Tanaka, Citrus reticulata Blanco, Citrus sinensis L. Osbeck and Citrus paradisi Macf., as well as to determine the contact and fumigant toxicity of these oils and their repellent effect on C. maculatus adults. The GC-MS analysis identified 45 compounds in the essential oils; the major components were described as follows: C. latifolia (limonene 57.7%, γ-terpinene 17.2%, β-pinene 12.3%, α-pinene 2.0%), and C. sinensis (limonene 93.8%, myrcene 2.1%), C. reticulata (limonene 94.2%, myrcene 1.6%) and C. paradisi (limonene 94.2%, myrcene 1.8%). In the contact toxicity tests using treated cowpeas the LC50 values ranged from 943.9 to 1037.7 ppm, with the lowest value for C. latifolia and the highest for C. sinensis. The number of eggs and newly emerged adults was inversely proportional to essential oil concentration increase. In the fumigant toxicity test, LC50 values ranged from 10.2 to 12.98 μL/L air, with C. latifolia showing the best results. In the repellency test, the essential oils were classified as neutral at all concentrations. The percentages of oviposition reduction ranged from 29.74 to 71.66%, while reduction in emergence varied from 15.43 to 85.31%. Essential oils of citrus peels (industrial waste) could be widely used for C. maculatus control. Moreover, they could gain economic value if used on a large scale to produce essential oils. © 2016 Elsevier Ltd.

Nascimento G.A.,Federal University of Pernambuco | Souza E.V.M.,Federal University of Pernambuco | Campos-Ferreira D.S.,Federal University of Pernambuco | Arruda M.S.,Federal University of Pernambuco | And 6 more authors.
Biosensors and Bioelectronics | Year: 2012

A new electrochemical DNA biosensor for bovine papillomavirus (BPV) detection that was based on screen-printed electrodes was comprehensively studied by electrochemical methods of cyclic voltammetry (CV) and differential pulse voltammetry (DPV). A BPV probe was immobilised on a working electrode (gold) modified with a polymeric film of poly-L-lysine (PLL) and chitosan. The experimental design was carried out to evaluate the influence of polymers, probe concentration (BPV probe) and immobilisation time on the electrochemical reduction of methylene blue (MB). The polymer poly-L-lysine (PLL), a probe concentration of 1 μM and an immobilisation time of 60. min showed the best result for the BPV probe immobilisation. With the hybridisation of a complementary target sequence (BPV target), the electrochemical signal decreased compared to a BPV probe immobilised on the modified PLL-gold electrode. Viral DNA that was extracted from cattle with papillomatosis also showed a decrease in the MB electrochemical reduction, which suggested that the decreased electrochemical signal corresponded to a bovine papillomavirus infection. The hybridisation specificity experiments further indicated that the biosensor could discriminate the complementary sequence from the non-complementary sequence. Thus, the results showed that the development of analytical devices, such as a biosensor, could assist in the rapid and efficient detection of bovine papillomavirus DNA and help in the prevention and treatment of papillomatosis in cattle. © 2012 Elsevier B.V.

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