108 resultados para Palm oil


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study aimed to test the hypothesis that the efficiency of a finishing period can be improved by reducing the initial fat content of fish fillets, by means of a period of food deprivation. Two groups of rainbow trout (Oncorhynchus mykiss) were fed for an 18-week grow-out period on a vegetable oil-based diet (VO) or a fish oil-based diet (FO). VO fed fish were then split into two sub groups: one (VO/FO) was shifted to the FO diet for 8 weeks, whilst the other (UF/FO) was deprived of food (unfed) for 2 weeks and then fed the FO diet for the remaining 6 weeks. The control treatment (FO/FO) was represented by fish continuously fed FO. The subsequent reduction of total fat in the UF/FO treatment was then responsible for a much faster recovery towards a FO-like fatty acid profile, validating the proposed hypothesis. However, the modification of the fatty acid composition of fish fillets during the feed withholding period, coupled with the postponement of the finishing diet, resulted in only minor beneficial effects of this strategy, and the loss of potential weight gain. However, the n-3 LC-PUFA content in UF/VO fish fillets was significantly higher than fish subjected to the VO/FO treatment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The research describes a rapid method for the determination of fatty acid (FA) contents in a micro-encapsulated fish-oil (μEFO) supplement by using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic technique and partial least square regression (PLSR) analysis. Using the ATR-FTIR technique, the μEFO powder samples can be directly analysed without any pre-treatment required, and our developed PLSR strategic approach based on the acquired spectral data led to production of a good linear calibration with R2 = 0.99. In addition, the subsequent predictions acquired from an independent validation set for the target FA compositions (i.e., total oil, total omega-3 fatty acids, EPA and DHA) were highly accurate when compared to the actual values obtained from standard GC-based technique, with plots between predicted versus actual values resulting in excellent linear fitting (R2 ⩾ 0.96) in all cases. The study therefore demonstrated not only the substantial advantage of the ATR-FTIR technique in terms of rapidness and cost effectiveness, but also its potential application as a rapid, potentially automated, online monitoring technique for the routine analysis of FA composition in industrial processes when used together with the multivariate.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The implementation of alternative lipid sources for use in aquaculture is of considerable interest globally. However, the possible benefit of using stearidonic acid (SDA)–rich fish oil (FO) alternatives has led to scientific confusion. Two hundred and forty rainbow trout (Oncorhynchus mykiss) were fed 1 of 4 diets (3 replicate tanks/treatment) containing either FO, linseed oil (LO), echium oil, or mixed vegetable oil (72% LO, 23% sunflower oil, and 6% canola oil) as the dietary lipid source (16.5%) for 73 d to investigate the competition and long-chain PUFA (LC-PUFA) biosynthesis between the fatty acid substrates α-linolenic acid (ALA) and SDA. SDA was more efficiently bioconverted to LC-PUFA compared with ALA. However, when the dietary lipid sources were directly compared, the increased provision of C18 PUFA within the LO diet resulted in no significant differences in (n-3) LC-PUFA content compared with fish fed the other diets. This study therefore shows that, rather than the previously speculated substrate competition, the limiting process in the apparent in vivo (n-3) LC-PUFA biosynthesis appears to be substrate availability. Rainbow trout fed the SDA- and ALA-rich dietary lipid sources subsequently had similar significant reductions in (n-3) LC-PUFA compared with fish fed the FO diet, therefore providing no additional dietary benefit on (n-3) LC-PUFA concentrations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new electrochemical method was developed to investigate crevice corrosion and its inhibitors. A wire beam electrode was used to allow electrochemical parameters to be measured directly from the crevice area. As an example, oil stain was investigated using this method.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fish transport is one of the most stressful procedures in aquaculture facilities. The present work evaluated the stress response of matrinxã to transportation procedures, and the use of clove oil as an alternative to reduce the stress response to transport in matrinxã (Brycon cephalus). Clove oil solutions were tested in concentrations of 0, 1, 5 and 10 mg/L during matrinxã transportation in plastic bags, supplied with water and oxygen as the usual field procedures in Brazil. Clove oil reduced some of the physiological stress responses (plasma cortisol, glucose and ions) that we measured. The high energetic cost to matrinxã cope with the transport stress was clear by the decrease of liver glycogen after transport. Our results suggest that clove oil (5 mg/l) can mitigate the stress response in matrinxã subjected to transport.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Latest trends in waste heat recovery include systems like Thermo Electric Generation (TEG), Rankine cycle, and active warm up systems. The advantages and disadvantages of different approaches are critically discussed and compared with a novel and effective oil heating system that can deliver between 7% and 12% reductions of CO2 emissions and fuel consumption. The comparison includes the expected CO2 and fuel saving potential related to the legal drive cycle as well as real world driving, effects on regulated exhaust emissions, utilisation of resources, maintenance and service, vehicle performance, comfort, noise, and durability.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background
The effects of fish oil (FO) supplementation and the dietary replacement of FO with flaxseed oil (FlaxO) and canola oil (CO) on the growth of cultured abalone was investigated. The study involved three growth experiments: (E1) diets containing 0.5, 1.0, 1.5, 2.0 and 2.5% of FO, respectively; (E2) diets in which FO was serially replaced by 25, 50, 75 and 100% FlaxO, respectively; and (E3) diets in which FO was serially replaced by 25, 50, 75 and 100% CO, respectively.

Results
In Experiment 1, abalone fed a diet supplemented with 1.5% FO showed a significantly higher (121.2 ± 1.1 mg day−1) daily growth rate of weight (DGRw) compared to control (70.1 ± 1.71 mg day−1). In Experiment 2, abalone fed 1.5% FO diet and diets containing 25–75% FlaxO showed no significant differences in DGRw. The diet containing 100% FlaxO showed significantly lower (63.3 ± 6.7 mg day−1) DGRw. In Experiment 3, abalone fed diets containing 25% and 50% CO showed similar DGRw as those fed a 1.5% FO diet. The diet containing 75% and 100% CO showed significantly lower (63.7 ± 5.0 to 95.4 ± 5.1 mg day−1) DGRw.

Conclusion
Supplementation with 1.5% of dietary FO can improve growth performance in cultured abalone. It is feasible to replace 75% of dietary FO with FlaxO and 50% of dietary FO with CO, without negative effect on growth performance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Since the democratic elections held across Iraq in 2005 and 2010 much attention has understandably been paid to the new Iraqi government. Unfortunately, it has become increasingly clear that much of Iraq’s political elite are practising the type of governance referred to in the literature on other Arab states alternatively as ‘liberalised autocracy’ (Brumberg, 2002), ‘semi-authoritarianism’ (Ottaway, 2003) or ‘pluralised authoritarianism’ (Posusney & Angrist, 2005). That is to say, that the Iraqi government actually utilises (and controls) nominally democratic mechanisms such as elections, media freedoms, political opposition and civil society as part of their strategy to retain power. This is perhaps best demonstrated via the nine month political stalemate that followed the March 2010 elections and PM Maliki’s refusal to step down despite having narrowly lost the election. Not surprisingly, the Iraqi people have become increasingly disillusioned and critical of their political leaders – hence the mass protests that have swept across Iraq in the context of the popular Arab Revolutions of 2010-11.

However, these latest Iraqi protests are only the most recent and overt sign of the hidden geographies that are agitating towards democracy in this deeply troubled and increasingly authoritarian state. Since the invasion of 2003, a complex array of political, religious and ethno-sectarian factions have formed civil society movements; uncensored news has been consumed across the nation; ordinary citizens have taken to the streets to protest key government decisions; and various local councils have been formed, deliberating on key decisions facing their immediate communities (Davis, 2004, 2007). Given this context, this chapter focuses on the specific case of the Iraqi Federation of Oil Unions (IFOU), Iraq’s largest and most powerful independent workers union. The IFOU has repeatedly taken the Iraqi government to task over their poor pay and the dangerous nature of their work, as well as the government’s initial kowtowing to US plans to privatise the entire Iraqi oil sector. To do this, the IFOU have utilised a variety of very democratic mechanisms including peaceful strikes and protests, media campaigns and political lobbying. Such moves have met with mixed results in Baghdad – at times the central government has pandered to the requests of IFOU, but it has also gone as far as issuing arrest warrants for its senior members. The IFOU therefore serve as an interesting example of public power in Iraq and may well pose one of the greatest challenges to rising authoritarianism there.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Since the invasion of 2003, a complex array of political, religious and ethno-sectarian factions have formed civil society movements; uncensored news has been consumed across the nation; ordinary citizens have taken to the streets to protest key government decisions; and various local councils have been formed, deliberating on key decisions facing their immediate communities. Given this context, this paper focuses on the specific case of the Iraqi Federation of Oil Unions (IFOU), Iraq’s largest and most powerful independent workers union. The IFOU has repeatedly taken the Iraqi government to task over their poor pay and the dangerous nature of their work, as well as the government’s initial kowtowing to US plans to privatise the entire Iraqi oil sector. To do this, the IFOU have utilised a variety of very democratic mechanisms including peaceful strikes and protests, media campaigns and political lobbying. Such moves have met with mixed results in Baghdad – at times the central government has pandered to the requests of IFOU, but it has also gone as far as issuing arrest warrants for its senior members. The IFOU therefore serve as an interesting example of public power in Iraq and may well pose one of the greatest challenges to rising authoritarianism there.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Triplicate groups of 20 European sea bass (35 g) were fed five diets in which the added lipid was 100% fish oil (FO), 40% (CSO40), 60% (CSO60), 80% (CSO80) and 100% (CSO100) refined cottonseed oil (CSO), for a period of 120 days. Overall fish growth, feed conversion ratio and protein utilization were unaffected by dietary treatment, but hepatosomatic and visceral fat indexes increased with increasing dietary CSO. Fillet fatty acid composition of total lipids reflected the fatty acids in the test diets. The monounsaturated fatty acids were significantly higher in fillet of fish fed diet FO, CSO40 and CSO60 compared to other treatments while saturated and polyunsaturated fatty acids (PUFA) were not affected by the dietary treatment. Some fatty acids (18:0, 18:1n-9, 20:5n-3 and 22:6n-3) were present in higher concentration in fillet lipid than in the CSO100 dietary lipid indicating accumulation in fillet relative to test diets. Retention of n-3 LC-PUFA within the fillet was increasingly inefficient among fish fed increasing levels of FO. Thus, this study suggests that CSO can be considered as a relatively effective substitute for fish oil in European sea bass (35 g) in terms of growth performances and feed efficiency as far as fish meal is present in the diet.