Potential bioavailability of protein and lipids in feed ingredients for the three‐spot cichlid Amphilophus trimaculatus: An in vitro assessment     

Francisco J. Toledo‐Solís  Rafael Martínez‐García  Manuel Díaz  Emyr Saul Pea Marín  Maria Paula Di Yorio  Paula Gabriela Vissio  Carlos Alfonso lvarez‐Gonzlez  Miguel Saenz de Rodrigez 《Aquaculture Research》2020,51(7):2913-2925

For the commercial culture of the three‐spot cichlid (Amphilophus trimaculatus), it is important to have available a set of protein and lipid ingredients suitable for feed manufacturing, which allow to optimize the culture at affordable costs. The in vitro digestibility was evaluated with pH‐stat technique, using stomach and intestine multi‐enzymatic extracts from A. trimaculatus juveniles. The digestion of protein ingredients was taken place both in acid and in alkaline conditions, quantifying the total of free amino acids at the end of the hydrolysis, whereas the digestion of lipid ingredients was taken place only in alkaline conditions. The digestive enzymes of this species showed a better affinity to raw materials of animal origin such as beef meal, fish meal and premium chicken meal, which presented better digestibility. The best lipid ingredient that could be used is the fish oil. However, it is possible to use ingredients from the plant sources, such as soy or cereals, and vegetable oils such as olive, corn or soy oil. It is necessary to complement this study in vitro with the digestibility analysis in vivo, in order to determine the inclusion percentages in feeds and costs and therefore to develop an efficient feed formulation for the aquaculture of A. trimaculatus.  相似文献   

Biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum) using two bacterial isolates (LE89 and LE141) of Pseudomonas fluorescens     

Concepcin Gonzlez‐Palacios  Juan‐Miguel Fregeneda‐Grandes  Jos‐Miguel Aller‐Gancedo 《Journal of fish diseases》2019,42(2):269-275

The probiotic activity of 15 bacterial isolates that inhibit Saprolegnia parasitica in vitro was tested for the biocontrol of saprolegniosis in rainbow trout (Oncorhynchus mykiss Walbaum), adding the bacteria to tank water for 14 days at a concentration of 10⁶ bacteria ml^?1 water. Pseudomonas fluorescens LE89 and Pseudomonas fluorescens LE141 were effective in controlling experimental infection with S. parasitica since of the fish treated with LE89, 24.5% ± 16.27% (p < 0.05) became infected, as did 42.8% ± 8.41% (p < 0.05) of those treated with LE141. Given their protective effect when administered in water, their effect was also studied when administered in feed before and after experimental infection. Both bacterial isolates survived low pH levels and the action of bile, grew in skin and intestinal mucus, were resistant to several antibiotics and survived in feed; however, neither of the two isolates prevented S. parasitica infection when administered in feed.  相似文献   

Effects of anthropogenic noise as a source of acoustic stress in wild populations of Hippocampus guttulatus in the Ria Formosa,south Portugal     

Jorge Palma  Marisa Magalhes  Miguel Correia  Jos Pedro Andrade 《水产资源保护:海洋与淡水生态系统》2019,29(5):751-759

Impact of Caligus treatments on unit costs of heterogeneous salmon farms in Chile     

Jorge Dresdner  Carlos Chávez  Miguel Quiroga  Daniel Jiménez  Paulina Artacho  Alfredo Tello 《Aquaculture Economics & Management (Blackwell Science)》2019,23(1):1-27

We measure the impact that sanitary treatments that control ectoparasite Caligus rogercresseyi abundance have on unit production costs of Salmo salar farms in Chile. We follow complete production cycles for a sample of farms between 2009 and 2015. We estimate a simultaneous salmon biomass growth and Caligus abundance model. The statistical analysis determines the effect of antiparasitic treatments, location of farms, environmental conditions and Caligus abundance on the salmon growth profile. Using outside cost information, we simulate how unit production costs vary by treatment and farm characteristics. Our results suggest that unit production costs increase on average by $1.4?US/kg with Caligus and treatments. Treatment costs are compensated by higher harvesting levels, and unit production costs are invariant to the situation without treatment. All estimated effects differ depending on farm’s environmental and spatial conditions, suggesting that the design of cost-effective intervention calls for discriminatory regulation under heterogeneous conditions.  相似文献   

Hybridization and invasive species in a threatened freshwater fish community under environmental pressures: Morphometric and molecular evidence     

Lucía Galvez-Bravo  Anabel Perdices  R. J. De Miguel  Ángela Lambea-Camblor  Charlotte Penney  Carlo Meloro  Begoña Martinez-Cruz  Richard P. Brown 《水产资源保护:海洋与淡水生态系统》2024,34(1):e4046

Identification of genetic sources with attenuated <Emphasis Type="Italic">Tomato chlorosis virus</Emphasis>-induced symptoms in <Emphasis Type="Italic">Solanum</Emphasis> (section <Emphasis Type="Italic">Lycopersicon</Emphasis>) germplasm     

Matías González-Arcos  Maria Esther de Noronha Fonseca  Ana Arruabarrena  Mirtes F. Lima  Miguel Michereff-Filho  Enrique Moriones  Rafael Fernández-Muñoz  Leonardo S. Boiteux 《Euphytica》2018,214(10):178

The whitefly-transmitted Tomato chlorosis virus (ToCV) (genus Crinivirus) is associated with yield and quality losses in field and greenhouse-grown tomatoes (Solanum lycopersicum) in South America. Therefore, the search for sources of ToCV resistance/tolerance is a major breeding priority for this region. A germplasm of 33 Solanum (Lycopersicon) accessions (comprising cultivated and wild species) was evaluated for ToCV reaction in multi-year assays conducted under natural and experimental whitefly vector exposure in Uruguay and Brazil. Reaction to ToCV was assessed employing a symptom severity scale and systemic virus infection was evaluated via RT-PCR and/or molecular hybridization assays. A subgroup of accessions was also evaluated for whitefly reaction in two free-choice bioassays carried out in Uruguay (with Trialeurodes vaporariorum) and Brazil (with Bemisia tabaci Middle-East-Asia-Minor1—MEAM1?=?biotype B). The most stable sources of ToCV tolerance were identified in Solanum habrochaites PI 127827 (mild symptoms and low viral titers) and S. lycopersicum ‘LT05’ (mild symptoms but with high viral titers). These two accessions were efficiently colonized by both whitefly species, thus excluding the potential involvement of vector-resistance mechanisms. Other promising breeding sources were Solanum peruvianum (sensu lato) ‘CGO 6711’ (mild symptoms and low virus titers), Solanum chilense LA1967 (mild symptoms, but with high levels of B. tabaci MEAM1 oviposition) and Solanum pennellii LA0716 (intermediate symptoms and low level of B. tabaci MEAM1 oviposition). Additional studies are necessary to elucidate the genetic basis of the tolerance/resistance identified in this set of Solanum (Lycopersicon) accessions.  相似文献   

Effect of the Cooking Process on the Gelling Properties of Whole and Minced Jumbo Lump of Blue Crab (Callinectes sapidus)     

Miguel Angel Martínez-Maldonado  José Alberto Ramírez-De León  Ma. Guadalupe Méndez-Montealvo  Eduardo Morales-Sánchez 《Journal Of Aquatic Food Product Technology》2018,27(4):418-429

Commercially, crab meat is obtained by hand-picking after a cooking process, followed by pasteurizing or canning. Jumbo lump is one of the pieces of meat obtained from the blue crab. The aim of this study was to evaluate the effect of the commercial cooking process (boiling and steaming) on the mechanical and functional properties of whole jumbo lump and the gels obtained from cooked and minced jumbo lump from blue crab (Callinectes sapidus). The gels were prepared combining the washing process and microbial transglutaminase. The boiling and steaming processes showed a different effect on the textural and color properties. Whole jumbo lump pieces cooked by immersion in boiling water showed a higher hardness value as compared to steamed jumbo lump pieces, suggesting a different internal structural. The cooking processes used in this study did not modify the water holding capacity, gelling capability, or color of the minced jumbo lump. The addition of microbial transglutaminase to washed minced jumbo lump improved the hardness, cohesiveness, and chewiness of gels elaborated with boiled or steamed jumbo lump, which allowed the textural properties similar to those of the whole jumbo lump.  相似文献   

Effects of Agave fructans (<Emphasis Type="Italic">Agave tequilana</Emphasis> Weber var. azul) on Body Fat and Serum Lipids in Obesity     

Eduardo Padilla-Camberos  Carla P. Barragán-Álvarez  Nestor E. Diaz-Martinez  Vineet Rathod  José Miguel Flores-Fernández 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(1):34-39

Obesity affects millions of people worldwide, constituting a public health problem associated with premature mortality. Agave fructans decrease fat mass, body and liver weight, and generate satiety in rodents. In the present study the effects of agave fructans on weight control, lipid profile, and physical tolerability were evaluated in obese people. Twenty-eight obese volunteers were randomly divided into two groups. In the first group, 96 mg/bw of agave fructans was administered for 12 weeks; in the second group, maltodextrin as a placebo was administered for 12 weeks. All participants consumed a low-calorie diet of 1500 kcal/day. Anthropometric and biochemical measurements were taken at baseline and at the end of the study. The body mass index (BMI) of the agave fructans treated group was reduced significantly from the baseline to the final measurements. Hip and waist circumferences decreased statistically in both groups. A decrease of 10% in total body fat was observed in the agave fructans treated group, resulting in a statistically significant difference in the final versus baseline measurements between the Agave fructans treated group and the placebo treated group. Triglycerides were reduced significantly in the agave fructans treated group. Glucose values did not change in either group. Agave fructans intake was safe and well tolerated throughout the study. The results showed that the ingestion of agave fructans enhanced the decrease in BMI, the decrease in total body fat, and the decrease in triglycerides in obese individuals who consume a low-calorie diet.  相似文献   

Molecular endocrine changes of Gh/Igf1 axis in gilthead sea bream (<Emphasis Type="Italic">Sparus aurata</Emphasis> L.) exposed to different environmental salinities during larvae to post-larvae stages     

Khaled Mohammed-Geba  Manuel Yúfera  Gonzalo Martínez-Rodríguez  Juan Miguel Mancera 《Fish physiology and biochemistry》2016,42(4):1177-1186

The influence of acclimation of the euryhaline gilthead sea bream (Sparus aurata) larvae/post-larvae to brackish water on growth, energetic contents, and mRNA levels of selected hormones and growth-regulating hypothalamic neurohormones was assessed. Specimens from 49 days post-hatching were acclimated during 28 days to two different environmental salinities: 38 and 20 psu (as brackish water). Both groups were then transferred to 38 psu and acclimated for an additional week. Early juveniles were sampled after 28 days of acclimation to both salinities and one week after transfer to 38 psu. Pituitary adenylate cyclase-activating peptide (adcyap1; pacap), somatostatin-I (sst1), growth hormone (gh1), insulin-like growth factor-I (igf1), and prolactin (prl) mRNA expression were all studied by QPCR. Post-larvae acclimated to 20 psu showed better growth performance and body energetic content than post-larvae maintained at 38 psu. prl, adcyap1, and igf1 mRNA expression levels increased in 20-psu-acclimated post-larvae but decreased upon transfer to 38 psu. GH1 expression did not show significant changes under both experimental conditions. Our results suggested an enhanced general performance for post-larvae in brackish water, supported by the actions of adcyap1, igf1, and prl.  相似文献   

Comparison of remote sensing indices for monitoring of desert cienegas     

Natalie R. Wilson  Laura M. Norman  Miguel Villarreal  Leila Gass  Ron Tiller  Andrew Salywon 《Arid Land Research and Management》2016,30(4):460-478

This research considers the applicability of different vegetation indices at 30 m resolution for mapping and monitoring desert wetland (cienega) health and spatial extent through time at Cienega Creek in southeastern Arizona, USA. Multiple stressors including the risk of decadal-scale drought, the effects of current and predicted global warming, and continued anthropogenic pressures threaten aquatic habitats in the southwest and cienegas are recognized as important sites for conservation and restoration efforts. However, cienegas present a challenge to satellite-imagery based analysis due to their small size and mixed surface cover of open water, exposed soils, and vegetation. We created time series of five well-known vegetation indices using annual Landsat Thematic Mapper (TM) images retrieved during the April–June dry season, from 1984 to 2011 to map landscape-level distribution of wetlands and monitor the temporal dynamics of individual sites. Indices included the Normalized Difference Vegetation Index (NDVI), the Soil-Adjusted Vegetation Index (SAVI), the Normalized Difference Water Index (NDWI), and the Normalized Difference Infrared Index (NDII). One topographic index, the Topographic Wetness Index (TWI), was analyzed to examine the utility of topography in mapping distribution of cienegas. Our results indicate that the NDII, calculated using Landsat TM band 5, outperforms the other indices at differentiating cienegas from riparian and upland sites, and was the best means to analyze change. As such, it offers a critical baseline for future studies that seek to extend the analysis of cienegas to other regions and time scales, and has broader applicability to the remote sensing of wetland features in arid landscapes.  相似文献