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101.
Sabrina M. Suita André Braga Eduardo Ballester Alessandro P. Cardozo Paulo Cesar Abreu Wilson WasieleskyJr 《Aquaculture International》2016,24(5):1473-1487
The aim of this study was to use preselected quality indicators for Litopenaeus vannamei post-larvae and the stable isotopes technique with δ13C and δ15N to determine the influence of bioflocs in shrimp feeding during the nursery phase, between PL1 and PL30. A control treatment (CT) with water renewal was compared to a biofloc treatment (BT) that received organic carbon fertilizations. Different types of commercial feed (Stresspak and Flake-INVE?, PL40-GUABI?), microalgae (Chaetoceros muelleri) and Artemia sp. nauplii were used as food sources. The physical and chemical parameters of water and ammonia were monitored daily, and nitrite, nitrate and alkalinity were measured weekly. Suspended solids and the microorganisms of bioflocs were characterized. At the end of the experiment, fifteen shrimps of each replicate were collected to evaluate nine larvae quality indicators. Isotopic values of 13C and 15N of food sources and shrimp tissues were collected on days 10, 20 and 30, and a Bayesian model of isotopic mixture measured the contributions of these sources to the shrimp biomass. Salinity, alkalinity and nitrite differed significantly between the treatments but were appropriate for post-larvae production. The larvae quality conditions in the CT treatment were ranked as “good,” whereas the BT conditions were considered “excellent” according to the analysis of larval quality parameters. The stable isotopes analysis showed that the PL40 GUABI? feed was the most important food source throughout the experimental period in the CT. In the BT (10th and 20th days), the bioflocs and commercial feeds (Flake-INVE?, PL40-GUABI?) did not present significant variations in their contribution ratios; however, on the 30th day, the contribution of the PL40-GUABI? feed was higher when compared to bioflocs. In general, the commercial feed played a more important role as a food source for Litopenaeus vannamei larvae during the nursery phase, although the consumption of bioflocs led to a better larvae quality. 相似文献
102.
A. SAGSTAD M. SANDEN Å. KROGDAHL A.M. BAKKE‐McKELLEP M. FRØYSTAD G.‐I. HEMRE 《Aquaculture Nutrition》2008,14(6):556-572
The present experiment was conducted to study the possible effects of genetically modified (GM), full‐fat soybean meal (FFSBM) from Round‐up Ready® soybeans compared to its parental, and closest near‐isogenic, non‐modified (nGM) soybean variety, added at moderate (150 g kg?1) and high (300 g kg?1) inclusion levels. The fish showed a high specific growth rate (SGR 1.27–1.52), and nearly doubled their body weight (BW), with final weights varying from 1009 to 1110 g. Increased levels of dietary FFSBM, independent of the soy being GM or not, significantly decreased mean values of SGR, thermal growth rate, condition factor, final BW, liver somatic index, lipid efficiency ratio, apparent digestibility coefficients (ADC) of protein and gross energy, liver lipid content and plasma cholesterol, and significantly increased ADC of starch and muscle fatty acid levels of 18:3n‐3, 20:4n‐6, 20:5n‐3 and total n‐3. Increasing dietary GM FFSBM significantly increased feed conversion ratio, and significantly decreased protein efficiency ratio, ADC of lipid and dry matter and plasma triacylglycerol (TAG) levels. Spleen somatic index was significantly larger in fish groups fed GM FFSBM compared to groups fed nGM FFSBM, which might indicate a possible immune response exerted by the GM soybeans. Mean normalized expression of heat shock protein 70 mRNA in distal intestine was significantly up‐regulated while normalized expression of catalase in liver was down‐regulated, in fish fed FFSBM compared to fish fed FM. In conclusion, substituting moderate to high levels of GM Round‐up Ready® FFSBM in diets for Atlantic salmon and compared to the closest near‐isogenic counterpart available, resulted in many effects independent of the soy being GM or not, but with the notable exceptions of enlarged spleen and lowered plasma TAG. 相似文献
103.
Marcelo Braga Bueno Guerra Carlos Ernesto G. R. Schaefer Paula de Freitas Rosa Felipe N. B. Simas Thiago T. C. Pereira Edenir Rodrigues Pereira-Filho 《Water, air, and soil pollution》2011,222(1-4):91-102
Technosols are anthropogenic soils that may be strongly impacted by heavy metal deposition, which have not yet been described in Antarctica. In this paper, we present a chemical study of what is supposedly the oldest manmade soil from Antarctic Peninsula, developed in the vicinity of Trinity House and Nordenskjold Hut at Hope Bay. Chemical and morphological soil attributes indicate that a former ornithogenic site (penguin rookery) was further subjected to human disturbance, following local exploration since 1903. We detected very high amounts of heavy metals such as Cd, Cu, Pb, and Zn. For the most impacted site, pseudototal concentrations of these elements reach 47, 2,082, 19,381, and 5,225 mg kg?1, respectively. Enrichment factors were calculated using Zr as reference element, and high values were found for these contaminated sites, qualifying some of them as extremely polluted. Also, both the mobilizable and mobile fraction of Cd and Pb indicate the need of intervention in the affected area. These findings are all consistent with the human impacts and strong contamination. Strong positive correlation between the pseudototal concentrations of Cd, Cu, Mn, Ni, Pb, and Zn indicates a similar source of pollution. These soils may represent the oldest Technosols in Antarctic Continent. 相似文献
104.
Tiago Braga Maria João Rodrigues Hugo Pereira João Varela Luísa Barreira Mercedes González-Wangüemert 《Journal Of Aquatic Food Product Technology》2017,26(10):1337-1350
Marine invertebrates contain nutritionally important elements that make them suitable to be included in the human diet, and they are considered an outstanding source of secondary metabolites with multiple biotechnological uses. The sea hare Bursatella leachii is an invasive species in Mar Menor that can be managed through the control of its reproduction and/or by massive biomass removal. In this context, this work evaluated the possible use of biomass from B. leachii in the food and cosmetics industries. Biomass was appraised for nutritional properties, and extracts were prepared and evaluated in vitro for antioxidant and anti-inflammatory capacity, cholinesterase and tyrosinase inhibition, and for total contents in different phenolic groups. It had a moderate moisture level, low ash and fat levels, and an adequate protein amount and protein/lipid ratio. The fatty acids (FA) profile was mainly saturated, dominated by palmitic acid. The methanol extract had the highest acetylcholinesterase inhibition. The acetone extract had the strongest capacity to scavenge 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical, reduce iron, inhibit tyrosinase, decrease nitric oxide production in lipopolysaccharide (LPS)-stimulated microglia cells, and the upmost levels of total phenolics, flavonoids, and tannins. Our results suggest multiple biotechnological applications for B. leachii biomass in different economic areas. 相似文献
105.
Feeding,body condition and reproductive investment of Astyanax intermedius (Characiformes,Characidae) in relation to rainfall and temperature in a Brazilian Atlantic Forest stream
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Ursulla P. Souza Fabio C. Ferreira Francisco M. de S. Braga Kirk O. Winemiller 《Ecology of Freshwater Fish》2015,24(1):123-132
Life history theory seeks to explain how environmental variation selects for patterns of investment in growth and survival relative to production and survival of offspring. Seasonal variations in rainfall and temperature provide environmental cues for spawning by many tropical freshwater fishes. To investigate environment–life history associations, we conducted a one‐year study of Astyanax intermedius in an Atlantic Forest stream of southeastern Brazil. Our analysis focused on temporal variation in feeding, body condition and reproduction in relation to rainfall and water temperature. For mature females, food intake was not significantly correlated with rainfall or temperature; however, body condition was negatively correlated with rainfall and water temperature. Female reproductive effort was positively correlated with water temperature, but did not vary with rainfall. For males and juveniles, there was no significant relationship between food intake or body condition and either environmental variable. Testis weight was negatively correlated with rainfall, but was not significantly correlated with water temperature. We detected a negative correlation between gonad mass with body condition and food intake for females but not for males. Our results differed from other studies in tropical and subtropical areas where rainfall has been shown to be positively correlated with fish reproductive effort. Our results indicate that reproductive effort of males is relatively constant throughout the year, whereas for females, it increases with increasing water temperature. This increase in reproductive investment in concert with an increasing temperature and metabolic rate may incur a trade‐off with somatic growth and survival for this small stream fish. 相似文献
106.
The ethanol extract and fractions from Coccoloba acrostichoides aerial parts were assayed for in vitro antimicrobial activity. The extract was active against the assayed bacteria while most of the fractions also inhibited fungal growth, especially the n-hexane and EtOAc fractions. The isolated beta-sitosterol and betulin were tested, being the last one active against Fusarium oxysporum. 相似文献
107.
Andressa Reis Alitcia Moraes Kleinowski Fátima Rosane Schuquel Klein Renata Trevizan Telles Luciano do Amarante Eugenia Jacira Bolacel Braga 《Journal of Crop Science and Biotechnology》2015,18(5):349-357
In tissue culture, several chemical and physiological factors can influence the production of secondary metabolites. The growth response and increased secondary metabolite production generated by a high irradiance environment, can be used to determine a favorable habitat for the growth and conservation of medicinal plants. Thus, the present study aimed to evaluate the influence of light quality on growth and production of secondary metabolites in Alternanthera sessilis (L.) R. Br. ex DC. (sessile joyweed), Alternanthera philoxeroides (Mart.) Grisebach (alligatorweed), Alternanthera tenella Colla (joyweed), and Alternanthera brasiliana (L.) Kuntze (Brazilian joyweed) plants cultured in vitro. The species were grown in MS medium, for 45 days in different light qualities (blue, white, and red). Growth parameters and biochemical analysis were performed at the end of the study. The results show that the red light allowed a higher accumulation of biomass in most species; red and white light were great inductors for the production of betacyanin and the blue light favored the enhancement of flavonoids. In this manner, the quality of light can affect the betacyanin, betaxanthin, and flavonoid biosynthesis as well as growth patterns in the related Alternanthera species. Based on the data presented, we suggest that specific genes can encode the pigment production according to the light quality which exhibit distinct activation patterns in different plant species. 相似文献
108.
Ferreira SR de Araújo JV Braga FR Araujo JM Fernandes FM 《Tropical animal health and production》2011,43(8):1589-1593
One isolate of predator fungi Duddingtonia flagrans (AC001) was assessed in vitro regarding the capacity of supporting the passage through pigs' gastrointestinal tract without
loss of the ability of preying infective larvae Oesophagostomum spp. Fungal isolates survived the passage and were efficient in preying L3 since the first 8 h of collection (p < 0.01) in relation to the control group (without fungus). Compared with control, there was a significant decrease (p < 0.01) of 59.6% (8 h), 71.7% (12 h), 76.8% (24 h), 81.0% (36 h), 78.0% (48 h), 76.1% (72 h), and 82.7% (96 h) in means of
infective larvae Oesophagostomum spp. recovered from treatments with isolate AC001. Linear regression coefficients of L3 of recovered Oesophagostomum spp. regarding the collections due to time were −0.621 for control, −1.40 for AC001, and −2.64 for NF34. Fungi D. flagrans (AC001) had demonstrated to be promising for use in the biological control of pig parasite Oesophagostomum spp. 相似文献
109.
Silva Roberta Polyana Araújo da Lôbo Raimundo Nonato Braga El Faro Lenira dos Santos Glaucyana Gouvêa Bruneli Frank Ângelo Tomita Peixoto Maria Gabriela Campolina Diniz 《Tropical animal health and production》2020,52(5):2513-2522
Tropical Animal Health and Production - This study aimed to estimate the genetic parameters for somatic cell count (SCC) and the genetic association between SCC and milk production traits using two... 相似文献
110.
Patrícia de Mello Papa Priscilla Nascimento Guasti Bruna De Vita Nathalia Genú Nakazato Leandro Maia Camila de Paula Freitas Dell’Aqua Verônica Flores da Cunha Scheeren Lorenzo Garrido Teixeira Martini Segabinazzi Luiz Roberto Pena de Andrade Junior Luis Fernando Mercês Chaves Silva Endrigo Adonis Braga Araújo Sidnei Nunes Oliveira Frederico Ozanam Papa Fernanda da Cruz Landim-Alvarenga Marco Antonio Alvarenga 《Reproduction in domestic animals》2020,55(4):429-437
Although stem cell therapy is a promising alternative for treatment of degenerative diseases, there are just few reports on the use of stem cells therapy in horse's reproductive system. This study aims to evaluate the effect of intratesticular injection of bone marrow mesenchymal stromal/stem cells (MSCs) in healthy stallions, and its outcome on seminal parameters and fertility. In Experiment 1, 24 stallions were divided into treatment group (TG) and control group (CG). In the TG, an intratesticular application of MSC was performed, and in the CG, only PBS was used. Measurements of testicular volume, surface temperature and Doppler ultrasonography were performed 24 and 48 hr after treatments. Fifteen days after application, the testicles were removed and submitted to histological analysis. In Experiment 2, 3 fertile stallions received similarly treatment with MSCs. Physical examination and sperm analysis were performed weekly during 60 days after treatment, and at the end, semen from one of them was used for artificial inseminations of 6 healthy mares. In Experiment 1, clinical examinations showed no signals of acute inflammation on both groups according to the analysed variables (p > .05). Also, no signal of chronic inflammation was observed on histological evaluation. In Experiment 2, stallions presented no physical alterations or changes in sperm parameters, and a satisfactory fertility rate (83%; 5/6) was observed after AI. The results support the hypothesis that intratesticular application of bone marrow MSCs is a safe procedure, and this could be a promising alternative to treat testicular degenerative conditions. 相似文献