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61.
Metabolic enzyme activities in relation to crowding stress in the wedge sole (Dicologoglossa cuneata)
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Marcelino Herrera Ignacio Ruiz‐Jarabo Luis Vargas‐Chacoff Elena de la Roca Juan M Mancera 《Aquaculture Research》2015,46(11):2808-2818
In this work, we have assessed the effects of different stocking densities on the biometry, survival and physiological status of the wedge sole (Dicologoglossa cuneata), focusing on changes in the stress system and intermediate metabolism, with the aim of determining a stress indicator for chronic‐stress situations in this species. Wedge sole were kept at three different stocking densities (0.2, 0.4 and 0.8 kg m?3) for 197 days, and survival, growth, plasma metabolites, cortisol and enzymatic activities were assessed. Survival rates were the highest at low density, though growth did not vary significantly among treatments. Enzymatic activities, mainly in muscle, differed depending on stocking density. Liver hexokinase activity at low stocking density was the highest, while no differences were detected for the other enzymes assessed. In muscle, all enzymes significantly increased in activity with stocking density. We concluded that long‐term high stocking density culture significantly changed enzyme activities (hexokinase, glutamate dehydrogenase, glyceraldehyde 3‐phosphate dehydrogenase, and lactate dehydrogenase) in wedge sole muscle, although liver enzymes, plasma cortisol and metabolites did not vary significantly. Therefore, muscle enzymes, hexokinase and glutamate dehydrogenase, could be considered stress indicators for this species in chronic‐stress situations. 相似文献
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Herrera Mayra Denise Zegbe Jorge A. Melero-Meraz Valentín Cruz-Bravo Raquel K. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2021,76(4):427-433
Plant Foods for Human Nutrition - Prickly pear cactus fruit peels have been seen as organic waste. This study explored the effect of supplemental irrigation during fruit growth of ‘Roja... 相似文献
64.
Huertas Herrera Alejandro Promis Álvaro Toro-Manríquez Mónica Lencinas María Vanessa Martínez Pastur Guillermo Río Matías 《New Forests》2022,53(3):469-485
New Forests - In forests affected by heavy fires and continuous grazing of exotic herbivorous mammal species, Nothofagus pumilio (lenga) cannot recover naturally. The main factors that hinder the... 相似文献
65.
Production of Xylose from Sorghum Straw Using Hydrochloric Acid 总被引:1,自引:0,他引:1
Xylose is a hemicellulosic sugar mainly used for its bioconversion to xylitol. Sorghum straw is a raw material for xylose production that has been studied scarcely. The objective of this work was to study the xylose production by hydrolysis of sorghum straw with hydrochloric acid at 122 °C. Several concentrations of HCl (2–6%) and reaction time (0–300 min) were evaluated. Kinetic parameters of mathematical models for predicting the concentration of xylose, glucose, acetic acid and furfural in the hydrolysates were found. Optimal conditions for hydrolysis were 6% HCl at 122 °C for 70 min, which yielded a solution with 16·2 g xylose/L, 3·8 g glucose/L, 2·0 g furfural/L and 1·9 g acetic acid/L. 相似文献
66.
S. Andrés J. P. Vico V. Garrido M. J. Grilló S. Samper P. Gavín S. Herrera‐León R. C. Mainar‐Jaime 《Zoonoses and public health》2013,60(5):355-365
The epidemiology of subclinical salmonellosis in wild birds in a region of high Salmonella prevalence in pigs was studied. Three hundred and seventy‐nine faecal samples from 921 birds trapped in 31 locations nearby pig premises, and 431 samples from 581 birds of 10 natural settings far from pig farms were analysed for the presence of Salmonella spp. Positive samples were serotyped and analysed for antimicrobial resistance (AR). Phage typing and pulsed‐field gel electrophoresis (PFGE) on Salmonella Typhimurium isolates were also carried out. The overall proportion of Salmonella‐positive samples was 1.85% (95% CI = 0.93, 2.77). Salmonella isolation was positively associated with samples collected from birds in the proximity of a pig operation (OR = 16.5; 95% CI = 5.17, 52.65), and from non‐migratory (or short‐distance migration) birds (OR = 7.6; 95% CI = 1.20, 48.04) and negatively related to mostly granivorous birds (OR = 0.4; 95% CI = 0.15, 1.13). Salmonella Typhimurium was the most prevalent serotype and four different XbaI PFGE patterns were observed that matched the four phage types identified (U310, U311, DT164 and DT56). Only 20% of the strains showed multi‐AR. In three farms, a high degree of homogeneity among isolates from different birds was observed. These findings suggested that pig farms may act as amplifiers of this infection among wild birds, and the degree of bird density may have much to do on this transmission. Some of the Salmonella serotypes isolated from bird faeces were of potential zoonotic transmission and associated with AR. Monitoring salmonellosis in wild bird is advised. 相似文献
67.
Ivones Hernndez-Balmaseda Idania Rodeiro Guerra Ken Declerck Jos Alfredo Herrera Isidrn Claudina Prez-Novo Guy Van Camp Olivier De Wever Kethia Gonzlez Mayrel Labrada Adriana Carr Geovanni Dantas-Cassali Diego Carlos dos Reis Livan Delgado-Roche Roberto Rafael Nuez Ren Delgado-Hernndez Miguel David Fernndez Miriam T. Paz-Lopes Wim Vanden Berghe 《Marine drugs》2021,19(2)
68.
Janet Morffi Idania Rodeiro Sandra Luz Hernández Leonora González Jose Herrera J. Javier Espinosa-Aguirre 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):223-228
Mangifera indica stem bark extract (MSBE) is a Cuban natural product which has shown strong antioxidant properties. In this work, the antimutagenic effect of MSBE was tested against 10 well-known mutagens/carcinogens in the Ames test in the absence or presence of metabolic fraction (S9). The chemical mutagens tested included: cyclophosphamide, mitomycin C, bleomycin, cisplatin, dimethylnitrosamine (DMNA), benzo[a]pyrene (BP), 2-acetylaminofluorene (2-AAF), sodium azide, 1-nitropyrene (1-NP) and picrolonic acid. Protective effects of the extract were also evaluated by comparing the efficiency of S9 fraction obtained from rats treated during 28?days with oral doses of MSBE (50?C500?mg/kg) with that obtained from rats treated with vehicle (control) to activate bleomycin and cyclophosphamide in the Ames test. MSBE concentrations between 50 and 500???g/plate significantly reduced the mutagenicity mediated by all the chemicals tested with the exception of sodium azide. Higher mutagenicity was found when bleomycin and cyclophosphamide (CP) were activated by control S9 than by MSBE S9. In addition, inhibition of CYP1A1 microsomal activity was observed in the presence of MSBE (10?C20???g/ml). We can conclude that besides its potent antioxidant activity previously reported, MSBE may also exert a chemoprotective effect due to its capacity to inhibit CYP activity. 相似文献
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Ana Rodiles Ester Santigosa Marcelino Herrera Ismael Hachero-Cruzado María Luisa Cordero Silvia Martínez-Llorens Santosh P. Lall Francisco Javier Alarcón 《Aquaculture International》2012,20(6):1053-1070
The effect of dietary protein level and protein source on growth and proteolytic activity of juvenile Solea senegalensis was studied. In Experiment 1, fish were fed on four experimental diets containing increased protein levels (36, 46, 56 and 67%). In Experiment 2, Senegalese soles were fed on five diets with partial substitution of fish meal by soybean meal, soybean protein concentrate, soybean protein isolate, wheat gluten meal or pea protein concentrate. Results prove that growth and proteolytic activity in the distal intestine of fish were affected by the quantitative increase in dietary protein. The origin of protein source used in the elaboration of experimental diets affected both the amount and composition of the alkaline proteases secreted into the intestinal lumen; however, it did not decrease animal growth. Juvenile Senegalese sole showed capability to modulate digestive protease secretion when the concentration and/or source of dietary protein were modified. Quantity and quality of dietary protein affected protein hydrolysis in Senegalese sole intestine. This study establishes that 30% fish meal protein can be replaced by soybean derivatives without affecting intestinal proteases. Replacement with wheat gluten meal or pea protein concentrate should be taken cautiously, but further research is needed to establish whether growth performance and digestive enzyme physiology of Senegalese sole are affected by plant protein-supplemented diets in a long-term trial. 相似文献