Multivariate Data Analysis of the Thermal Performance of Portuguese Residential Building Stock

The purpose of this study is to explore the relationship between solar orientation, age (constructive characterization) and energy performance of Portuguese residential building stock and to assess the usefulness of exploring the Portuguese National System for Energy and Indoor Air Quality Certification of Buildings (SCE) database through multivariate analysis techniques. By using principal components technique, it was possible to condense the residential units’ features to only four principal components (PC): solar orientation; constructive characterization; geometry and energy performance, making information more workable. Grouping the entities into Clusters with favourable and unfavourable solar orientation and old buildings allowed to dilute the particularities of each entity, facilitating the interpretation of the data through generalization. A regression model was generated in order to explore/confirm which factors influence summer comfort the most. Using this approach, it was illustrated that the exploration of the SCE database through multivariate data analyses has an enormous potential to convert data into knowledge

Modulation of dietary protein to lipid ratios for gilthead seabream on-growing during summer temperature conditions

Gilthead seabream (Sparus aurata) tend to increase fat deposition during summer farming conditions in the Mediterranean, which may negatively affect productive performance and consumers' quality perception of the final product. Therefore, this study evaluated the impacts of protein to lipid ratios in low fishmeal/fish oil diets on growth performance, body composition, feed conversion and nutrient utilization of seabream on-grown during summer temperature conditions. The experimental diets contained low levels of fishmeal, fish oil, and crude protein (39%), differing in crude lipid content: 16% (MF diet) or 12% (LF diet). A growth trial was per-formed with seabream (initial weight: 100 & PLUSMN; 7 g) from August to October (water temperature: 23.1 & PLUSMN; 2.2 & DEG;C). A digestibility trial was also performed (at 23 & DEG;C). Key performance indicators, whole-body composition and ac-tivities of digestive enzymes were evaluated at the end of the experiment (64 days). Low dietary lipid levels negatively affected lipid, energy, and amino acid digestibility, and as a result, fish fed the LF diet presented higher nitrogen faecal losses. Still, the decrease in nutrient digestibility was not related to dietary effects on the digestive enzyme activities. The experimental diets did not compromise the activity of pancreatic, gastric, and intestinal digestive enzymes nor feed utilization, but a slight growth impairment was observed in fish fed the LF diet, probably due to the lower amino acid and lipid digestibility. However, a potential benefit of this dietary treatment towards reducing fat accumulation in seabream during summer was observed. Nevertheless, the environmental impact of the nitrogen losses during seabream on-growing should be considered when estimating the sustainability of the production. This study demonstrated that the optimisation of diet formulations should account for the environmental conditions, especially in Mediterranean aquaculture, so the economic and envi-ronmental impacts may be correctly evaluated towards a more sustainable fish production.info:eu-repo/semantics/publishedVersio

Effect of variable levels of dietary cholesterol and plant sterols on the growth performance and bone metabolism in gilthead seabream (Sparus aurata) juveniles

Cholesterol is found in all animal tissues and is an important component of biological cell membranes with functions such as precursor to bile acids, hormones and vitamins. Fish meal and fish oil are cholesterol-rich ingredients. Replacement of these marine-derived ingredients by plant proteins and vegetable oils tends to reduce dietary cholesterol levels

Effects of dietary curcumin in growth performance, oxidative status and gut morphometry and function of gilthead seabream postlarvae

An imbalance in the production and detoxification of reactive oxygen species and other oxidants can disrupt a l l types of cellular compounds, and lead to a state of oxidative stress. Preventing this state is essential to improve growth and health in animal production. Therefore, the aim of this work was to assess i f the dieta r y supple-mentation of curcumin cou l d improve the antioxidant status and intestine structu r e and functionalit y of gilthead seabream postlarvae, with the global objective of improving fish growth performance and robustness. Two experimental diets supplemented with different doses of curcumin (LOW and HIGH diets), and a commercial diet were fed to quadruplicate groups of postlarvae, for 20 days. At the end of the feeding trial fish fed the supple-mented diets significantly improved their antioxidant status compared to CTRL fed fish. LOW and HIGH fed fish presented lower protein oxidative damage (P 0.05). In conclusion, dieta r y curcumin supplementation was able to enhance gilthead seabream postlarvae robustness through a modulation of the oxidative status, increasing total antioxidant capacity and decreasing protein oxidative damage. This data pro-vide evidence that curcumin can be a suitable feed additive to promote heath status and robustness of fish at early stages of development, therefore contributing for the development and sustainabilit y of marine fish hatchery production.info:eu-repo/semantics/publishedVersio

Modulation of dietary protein to lipid ratios for gilthead seabream on-growing during summer temperature conditions

Gilthead seabream (Sparus aurata) tend to increase fat deposition during summer farming conditions in the Mediterranean, which may negatively affect productive performance and consumers’ quality perception of the final product. Therefore, this study evaluated the impacts of protein to lipid ratios in low fishmeal/fish oil diets on growth performance, body composition, feed conversion and nutrient utilization of seabream on-grown during summer temperature conditions. The experimental diets contained low levels of fishmeal, fish oil, and crude protein (39%), differing in crude lipid content: 16% (MF diet) or 12% (LF diet). A growth trial was performed with seabream (initial weight: 100 ± 7 g) from August to October (water temperature: 23.1 ± 2.2 ºC). A digestibility trial was also performed (at 23 ºC). Key performance indicators, whole-body composition and activities of digestive enzymes were evaluated at the end of the experiment (64 days). Low dietary lipid levels negatively affected lipid, energy, and amino acid digestibility, and as a result, fish fed the LF diet presented higher nitrogen faecal losses. Still, the decrease in nutrient digestibility was not related to dietary effects on the digestive enzyme activities. The experimental diets did not compromise the activity of pancreatic, gastric, and intestinal digestive enzymes nor feed utilization, but a slight growth impairment was observed in fish fed the LF diet, probably due to the lower amino acid and lipid digestibility. However, a potential benefit of this dietary treatment towards reducing fat accumulation in seabream during summer was observed. Nevertheless, the environmental impact of the nitrogen losses during seabream on-growing should be considered when estimating the sustainability of the production. This study demonstrated that the optimisation of diet formulations should account for the environmental conditions, especially in Mediterranean aquaculture, so the economic and environmental impacts may be correctly evaluated towards a more sustainable fish production.info:eu-repo/semantics/publishedVersio

Optimizing diets to decrease environmental impact of Nile tilapia (Oreochromis niloticus) production

Aquaculture is one of the most thriving animal production sectors, and Nile tilapia (Oreochromis niloticus) farming represents 8% of total finfish culture. However, the industry sustainability depends on the development of cost‐effective and environmental friendly feeds. This study aimed to reduce dietary protein levels in diets for juvenile tilapia and to minimize diet environmental impact while maximizing biological efficiency. A growth trial was performed using five isoenergetic plant protein‐based diets with decreasing levels of crude protein: 360, 340, 320, 300 and 280 g/kg diet (D360, D340, D320, D300 and D280, respectively). Dietary protein utilization was assessed by metabolic trials using a radiolabelled amino acid mixture. Tilapia in all treatments showed similar growth performance and feed intake. Feed conversion ratio was significantly higher in fish fed the D280 than the D360 diet, while no differences were found for other treatments. Protein retention was significantly higher in tilapia fed the D300 than the D360 diet. Amino acid catabolism increased in fish fed the D360 diet, though without significant differences in muscle amino acid retention. This study demonstrates that dietary protein levels can be reduced to 300 g/kg diet without hindering tilapia growth and feed conversion ratio, while reducing environmental nitrogen losses.FCT: UID/Multi/04326/2019/ IF/00482/2014/CP1217/CT0005/ DL57/2016/CP1361/CT0033.info:eu-repo/semantics/publishedVersio

A nutritional strategy to promote gilthead seabream performance under low temperatures

Gilthead seabream (Sparus aurata) is vulnerable to low water temperature, which may occur in the Southern Europe and Mediterranean region during Winter. Fish are poikilothermic animals, therefore feed intake, digestion, metabolism and ultimately growth are affected by water temperature. This study aimed to evaluate growth performance, feed utilisation, nutrient apparent digestibility, and nitrogen losses to the environment in gilthead seabream juveniles reared under low temperature (similar to 13 degrees C). Three isolipid and isoenergetic diets were formulated: a diet similar to a commercial feed (COM) that contained 44% crude protein and 27.5% fishmeal, and two experimental diets with a lower protein content of 42% (ECO and ECOSup). In both ECO diets fishmeal inclusion was reduced (10% in ECO and 7.5% in ECOSup diet) and 15% poultry meal was included. Additionally, the ECOSup diet was supplemented with a mix of feed additives intended to promote fish growth performance and feed intake. The ECO diets presented lower production costs than the COM diet, whilst incorporating more sustainable ingredients. Gilthead seabream juveniles (+/- 154.5 g initial body weight) were randomly assigned to triplicate tanks and fed the diets for 84 days. Fish fed the ECOSup diet attained a similar final body weight than fish fed the COM diet, significantly higher than fish fed the ECO diet. ECOSup fed fish presented significantly higher hepatosomatic index than COM fed fish, most likely due to higher hepatic glycogen reserves. The viscerosomatic index of ECOSup fed fish were significantly lower compared to COM fed fish, which is a positive achievement from a consumer's point of view. ECOSup diet exhibited similar nutrient digestibility than the COM diet. Moreover, feeding fish with the ECO diets resulted in lower faecal nitrogen losses when compared to COM fed fish. The results suggest that feeding gilthead seabream with an eco-friendly diet with a mix of feed additives such as the ECOSup diet, promoted growth and minimised nitrogen losses to the environment. Nutritional strategies that ultimately promote feed intake and diet utilisation are valuable tools that may help conditioning fish to sustain growth even under low temperatures.European UnionEuropean Commission [727315]; Portuguese Foundation for Science and Technology (Ministry of Science and Higher Education, Portugal) [DL 57/2016/CP1361/CT0033

Old Buildings’ Façades: Fieldwork and Discussion of Thermal Retrofitting Strategies in a Mediterranean Climate

This work is within the scope of thermal retrofitting, applied to old buildings’ façades (built between 1700 and 1960) located in Mediterranean climates, such as Portugal. The aim is to increase the sustainability of existing buildings, by reducing their energy consumption needs, for heating and cooling, and the corresponding gaseous emissions, while increasing their users’ comfort. Firstly, an analysis of the advantages and disadvantages of several thermal insulation solutions for façades was carried out, supported in current literature. Then, a survey of real retrofitting scenarios and interviews with experts was completed, to allow the selection of the most adequate thermal insulation techniques. Finally, as a result of this study, the discussion of retrofitting strategies was carried out to support the designer’s decision process, based on a flowchart with complementary tables, discussing the best thermal retrofitting technique to be implemented on old buildings’ façades, case-by-case

Mussel meal as a protein source in diets of gilthead seabream juveniles

Aquaculture Europe 2021, Funchal, Madeira, 4-7 OctoberIn 2020 world population was projected to increase from 7.8 billion to 9.9 billion by 2050 (http://worldpopulationreview.com). To overcome the stagnation of wild fisheries in supplying seafood for the growing population, Aquaculture will need to address several technical challenges to secure food demand (FAO, 2020). One of the challenges is to expand the number of sustainable raw materials to increase flexibility in the formulation of highly nutritious aquafeedsThis project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 818173 and by the Portuguese Foundation for Science and Technology (Ministry of Science and Higher Education, Portugal) through project UIDB/04326/2020 to CCMAR and contract DL 57/2016/CP1361/CT0033 to CA.N

Valorisation of aquaculture value-chains in the production of gilthead seabream juveniles

Aquaculture Europe 2022, International Conference & Exposition, September 27-30 2022, Rimini, ItalyAquaculture industry is a key animal production sector to secure the future food demand. Expanding the number of raw materials will increase flexibility in the formulation of highly nutritious aquafeeds and the sustainability of the sector. The inclusion of mussel meal originated from mussel aquaculture side-streams in aquafeeds will contribute to the valorisation of aquaculture value-chains and to the circular economy approach in the industry. The present study aimed to evaluate gilthead seabream (Sparus aurata) juveniles growth performance, feed utilisation, nutrient apparent digestibility, and nitrogen outputs to the environment when fed experimental diets with mussel meal as the main source of marine-derived proteinThis project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 818173 and by the Portuguese Foundation for Science and Technology (Ministry of Science and Higher Education, Portugal) through projects UIDB/04326/2020, UIDP/04326/2020, LA/P/0101/2020 to CCMAR and contract DL 57/2016/CP1361/CT0033 to CAN