Search

This study evaluated the use of microalgae (Aurantiochytrium sp.) meal as a substitute for fish oil in the diet of juvenile Pacific white shrimp (Litopenaeus vannamei) reared in a clear-water system. Dietary treatments at five replacement levels (0%, 25%, 50%, 75%, 100%) were performed in triplicate. After 46 days, only a slight difference in shrimp final weight was observed among treatments (0.61 g). An increase in final weight was observed with replacement of up to 50% fish oil for microalgae meal, while the optimal percentage of replacement estimated was 44.7%. Feed conversion rate (FCR) of animals fed a diet of Aurantiochytrium sp.meal to replace up to 50% fish oil decreased, and the optimal percentage of replacement estimated was 49.3%. The fatty acids profile in shrimp muscle tissue demonstrated an increase in docosahexaenoic acid (DHA) from 10.03% to 14.28% with increased replacement of fish oil by microalgae meal in the diet. Therefore, the partial replacement of fish oil by microalgae meal resulted in improved shrimp growth and FCR, and total replacement of dietary fish oil had no negative effects on these parameters. In addition, inclusion of microalgae meal raises the level of DHA in shrimp muscle. [ABSTRACT FROM AUTHOR]

Dietary intake of linoleic acid (LNA, 18:2n-6) has increased dramatically during the 20th century and is associated with greater prevalence of obesity. The endocannabinoid system is involved in regulation of energy balance and a sustained hyperactivity of the endocannabinoid system may contribute to obesity. Arachidonic acid (ARA, 20:4n-6) is the precursor for 2-AG and anandamide (AEA), and we sought to determine if low fat diets (LFD) could be made obesogenic by increasing the endocannabinoid precursor pool of ARA, causing excessive endocannabinoid signaling leading to weight gain and a metabolic profile associated with obesity. Mice (C57BL/6j, 6 weeks of age) were fed 1 en% LNA and 8 en% LNA in low fat (12.5 en%) and medium fat diets (MFD, 35 en%) for 16 weeks. We found that increasing dietary LNA from 1 to 8 en% in LFD and MFD significantly increased ARA in phospholipids (ARA-PL), elevated 2-AG and AEA in liver, elevated plasma leptin, and resulted in larger adipocytes and more macrophage infiltration in adipose tissue. In LFD, dietary LNA of 8 en% increased feed efficiency and caused greater weight gain than in an isocaloric reduction to 1 en% LNA. Increasing dietary LNA from 1 to 8 en% elevates liver endocannabinoid levels and increases the risk of developing obesity. Thus a high dietary content of LNA (8 en%) increases the adipogenic properties of a low fat diet. [ABSTRACT FROM AUTHOR]

The aim of this randomized, double-blinded, placebo-controlled, cross-over designed study was to demonstrate the clinical effect, registered by a survey, of a 10-week period of omega-3 fatty acid supplementation of the diet (1.53 g eicosapentaenoic acid (EPA) and 0.31 g DHA, both per 1000 kcal ME, equivalent to the complete diet) of 16 cats with radiologically documented, naturally occurring osteoarthritis (OA), in comparison with a 10-week period of supplementation with corn oil (0.00 g EPA and 0.00 g DHA, both per 1000 kcal ME). Cats on the fish oil revealed higher activity level (p = 0.07), more walking up and down the stairs (p = 0.07), less stiffness during gait (p = 0.03), more interaction with the owner (p = 0.07) and higher jumps (p = 0.03) compared to those on corn oil supplementation. In conclusion, supplementation of long-chain omega-3 polyunsaturated fatty acids changes the owner's perception of some aspects of behaviour and locomotion in cats with naturally occurring OA. [ABSTRACT FROM AUTHOR]

N-3 long-chain polyunsaturated fatty acids ( n-3 LC- PUFAs), in particular α-linolenic acid (18:3n-3), eicosapentaenoic acid ( EPA; 20:5n-3) and docosahexaenoic acid ( DHA; 22:6n-3) are receiving much attention because of their presumed beneficial health effects. To explain these, a variety of mechanisms have been proposed, but their interactions with the endocannabinoid system have received relatively little attention so far. However, it has already been shown some time ago that consumption of n-3 LC- PUFAs not only affects the synthesis of prototypic endocannabinoids like anandamide but also stimulates the formation of specific n-3 LC- PUFA-derived conjugates with ethanolamine, dopamine, serotonin or other amines. Some of these fatty amides show overlapping biological activities with those of typical endocannabinoids, whereas others possess distinct and sometimes largely unknown receptor affinities and other properties. The ethanolamine and dopamine conjugates of DHA have been the most investigated thus far. These mediators may provide promising new leads to the field of inflammatory and neurological disorders and for other pharmacological applications, including their use as carrier molecules for neurotransmitters to target the brain. Furthermore, combinations of n-3 LC- PUFA-derived fatty acid amides, their precursors and FAAH inhibitors offer possibilities to optimise their effects in health and disease. Linked Articles This article is part of a themed section on Cannabinoids. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-4 & http://dx.doi.org/10.1111/bph.2012.167.issue-8 [ABSTRACT FROM AUTHOR]

Cancer chemotherapy is associated with neutropenia and impaired neutrophil function. This study aimed to investigate whether supplementation with low dose fish oil (FO), providing n-3 polyunsaturated fatty acids, in cancer patients receiving chemotherapy after surgical tumor (mainly gastrointestinal) removal is able to improve the function of blood neutrophils. Patients ( n = 38) receiving chemotherapy (5-fluorouracil and leucovorin) were randomized into two groups; one group (control) did not receive a supplement, while the other group (FO) received 2 g FO/day for 8 weeks; the FO provided 0.3 g eicosapentaenoic acid plus 0.4 g docosahexaenoic acid per day. Patients in the control group lost an average of 2.5 kg of weight over the 8 weeks of the study. The number of blood polymorphonuclear cells (PMNC), mainly neutrophils, and their functions (phagocytosis and hydrogen peroxide production) decreased in the control group (average decreases of approximately 30, 45 and 17%, respectively). FO prevented these decreases and actually increased body weight (average of 1.7 kg weight gain; p < 0.002 vs. control group), PMNC number (average 29% increase), phagocytosis (average 14% increase) and superoxide production (average 28% increase). FO may be useful in preventing chemotherapy-induced decline in neutrophil number and function. [ABSTRACT FROM AUTHOR]

Essential fatty acids (EFA) remain one of the least well-understood and enigmatic nutrients in aquaculture nutrition. Of all dietary nutrients none has a greater direct impact on the composition of its consumer. Their importance stems not only to their impact on animal growth, but also to factors such as reproduction, immunity and product quality. Docosahexaenoic acid (DHA; 22:6n-3) has consistently been shown to provide the greatest EFA value to most species. However, the nutritional value of eicosapentaenoic (EPA; 20:5n-3) and arachidonic (ARA; 20:4n-6) acids has also been significantly greater than that exhibited by linolenic (LNA; 18:3n-3) and linoleic (LOA; 18:2n-6) acids. All five fatty acids have been shown to provide EFA value to most aquaculture species, although the optimal dietary inclusion levels and balance among the fatty-acid classes (n-3 and n-6) and fatty-acid chain lengths (18-C, 20-C or 22-C) vary among species. Environmental origin (freshwater, estuarine or marine) appears to be a primary factor influencing the difference in EFA requirements. The role that EFA play in osmoregulation clearly shows how these nutrients affect animals from different aquatic environments. The influence of EFA on growth also appears to be greatest in larval fish and crustaceans, possibly because of their reduced ability to digest and absorb lipids, but also because of a proportionally higher demand for EFA in the development of, in particular, neural tissues. Despite an abundance of research since the 1970s on the EFA requirements of aquaculture species there remains a need to better define the EFA requirements of most aquaculture species. Of all major aquaculture species only the penaeid shrimp has a comprehensively documented assessment of its nutritional requirements for EFA. The nutritional requirements for EFA in most fish species have not been comprehensively studied and those species that were fully examined in the 1970s and 1980s now need to be reassessed in light of recent changes to the use of high-nutrient-density diets that were not routinely used in either practice or research during that earlier period. In addition to changes in dietary specification strategies, declining dependence on marine-origin lipid sources in recent years has placed an increased imperative on understanding the dietary need for long-chain polyunsaturated fatty acids (lcPUFA). As aquaculture continues to grow there will be an increased use of alternative lipid resources, such as grain, algal and rendered oils, to provide dietary lipids. In addition to dietary dilution of natural EFA sources through the use of these raw materials, they will also bring new challenges, such as increased levels of n-6 and 18-C polyunsaturated fatty acids (PUFA). Introduction of these n-6 and PUFA fatty acids to the diet of aquaculture species will not only influence the nutritional demands of these animals, but will also affect their flesh quality characteristics by reducing their level of n-3 lcPUFA. This dilemma will demand an increased prioritisation on the value of lipid sources rich in n-3 lcPUFA, but is also likely to stimulate the development of alternative sources of lcPUFA. [ABSTRACT FROM AUTHOR]

Prevalence of postnatal depression (PND) occurs in approximately 13–20% of women after birth and has detrimental consequences for both the mother and the offspring. The causes of PND remain unclear, with research suggesting a multifactorial aetiology. It is believed that some dietary constituents may, in part, be related to the onset of PND. The possible protective roles of folate, riboflavin, calcium, magnesium and zinc intake have been investigated, as well as the role of a high glycaemic index diet, with conflicting results. Most of the literature appears to have focused on the symptoms of PND in relation to patterns of fish consumption and intake of n-3(omega-3) fatty acids. A review of studies published through MEDLINE indicated that riboflavin, calcium and zinc may play a role in alleviating symptoms of PND. Although a greater number of published papers have studied associations between n-3 intake and PND incidence, findings are somewhat contradictory. Further research is now required to develop these preliminary research findings with an aim to reducing the health costs of PND through the application of nutritional interventions. [ABSTRACT FROM AUTHOR]

One of the main factors hindering aquaculture production of American lobsters (Homarus americanus) is the need for a cost-effective and nutritionally sound diet. LiveArtemiaresults in good growth, but is expensive and is a constant source of contamination. FrozenArtemia, although lower in cost, generally results in decreased survivorship and growth relative to liveArtemia. The recent advent and mass production of enriched frozenArtemiaproducts may provide for a cost-effective and nutritionally complete food source for culturing American lobsters. Here, commercially available frozen adultArtemiaenriched with either n-3 fatty acids, orSpirulinawas fed to juvenile American lobsters, and their growth and survivorship for three months was compared with that of animals fed unenriched frozen adultArtemia. Both enrichedArtemiaproducts produced survivorship superior to that for animals fed unenrichedArtemia. Results for growth were equivocal although animals fed theSpirulina-enrichedArtemiahad the greatest condition factor. Although more costly by the end of the experiment, enriched diets were more economically efficient than unenrichedArtemia. This research demonstrates that enriched feedstuffs are cost-effective over longer time intervals, and benefits may continue beyond the hatchery-rearing phase. Enriched diets may also yield animals with a better condition factor, which may further influence their survivorship when released to the wild in enhancement programmes. [ABSTRACT FROM AUTHOR]

Reports on the composition of polyunsaturated fatty acids (PUFA) in milk from atopic and nonatopic mothers. Development of allergy in early infancy; Relationship between milk PUFA and atopic disease; Discussion on the significance of n-6 and n-3 PUFA in maternal milk for the development of atopic disease in children.

Background Supplementation with omega-3 (n-3) fatty acid or dietary fish may protect against atherosclerosis, but the potential mechanisms are unclear. Prior studies found modest triglyceride-lowering effects and slight increases in LDL (low-density lipoprotein) cholesterol. Limited evidence has examined n-3 effects on more detailed lipoprotein biomarkers. Methods and Results We conducted a study of 26 034 healthy women who reported information on fish and n-3 intake from a 131-item food-frequency questionnaire. We measured plasma lipids, apolipoproteins, and nuclear magnetic resonance spectroscopy lipoproteins and examined their associations with dietary intake of fish, total n-3, and the n-3 subtypes (eicosapentaenoic, docosahexaenoic, and α-linolenic acids). Top- versus bottom-quintile intake of fish and n-3 were significantly associated with lower triglyceride and large VLDL (very-low-density lipoprotein) particles. Fish intake, but not total n-3, was positively associated with total cholesterol, LDL cholesterol, apolipoprotein B, and larger LDL size, but only α-linolenic acid was associated with lower LDL cholesterol. Total n-3, docosahexaenoic acid, and α-linolenic acid intake were also positively associated with larger HDL (high-density lipoprotein) size and large HDL particles. High eicosapentaenoic acid intake was significantly associated with only a decreased level of VLDL particle concentration and VLDL triglyceride content. The n-3 fatty acids had some similarities but also differed in their associations with prospective cardiovascular disease risk patterns. Conclusions Higher consumption of fish and n-3 fatty acids were associated with multiple measures of lipoproteins that were mostly consistent with cardiovascular prevention, with differences noted for high intake of eicosapentaenoic acid versus docosahexaenoic acid and α-linolenic acid that were apparent with more detailed lipoprotein phenotyping. These hypothesis-generating findings warrant further study in clinical trials. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000479.