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This work was carried out to investigate the effect of dietary supplementation of fish oil on growth performance, carcass quality, immunological and serum biochemical parameters, total antioxidant capacity, intestinal morphology, mortality ratio and economic efficiency measures of broiler chicks. A total of 150 (ross 308) one day old chicks was distributed into 5 groups each contains 3 replicates (10 chicks/ replicate) fed on Five experimental diets contains different level of oils (0 oil, 1(SBO & FO), 2 FO and 3% FO respectively), during the experimental period (5 weeks). four chicks from each replicate were used for analysis of the experimental chicks. The results revealed that supplementation of fish oil in diets of broiler chicks 1,2 and 3 % improve (P< 0.05) the body weight (Bw) and body weight gain (BWG) than control groups but the best value were observed in 1&3% fish oil group beside improvement of feed conversion ratio (FCR) in all groups fed fish oil than control groups. However, numerically increased feed consumption in 1% SBO fed group than other groups. Significant (P< 0.05) improvement of carcass characteristics and dressing percentage gradually with fish oil supplementation. The values of USFA and n-3 PUFA were significantly (P< 0.05) higher in the breast muscle of broilers fed with fish oil compared to the control groups. But, SFA significantly (P< 0.05) decreased with fish oil than control groups. No significant difference in n-6 PUFA value between SBO and FO groups. So, N- 6:N3 ratio in breast meat decreased gradually with FO addition. Also, triglycerides, cholesterol, LDL and VLDL concentrations were significantly (P< 0.05) reduced by fish oil treatments, but serum HDL-c, total protein (TP), and globulin (GL) concentrations were significantly (P< 0.05) increased by using diets containing fish oil. Also, provision of fish oil Significantly (P< 0.05) improves immune response in broilers chicken against Newcastle virus vaccine through increase antibody titer and TLC with decreased mortality rate. Significant (P< 0.05) improvement of intestinal morphology with fish oil supplement were detected. The highest economic efficiency was recorded in group fed 1% FO followed by 1% SBO, 2% FO, 3% FO,0% oil gradually. from the present study, it could be concluded that the supplementation of fish oil in chick's diets significantly improve the growth performance, body composition, immune response, serum biochemical parameters, intestinal morphology, decrease the mortality rate and economically efficient at rate 1% addition

Several reports show that aquaculture is the fastest food-producing sector globally, contributing nearly half of global fish production from all sectors. However, there has been a steady decline in...

The aim of this study was to investigate the alteration in growth performance and lipid metabolism during the development of yellow fat in pigs. A total of 30 pigs (9.23 ± 0.21 kg) were assigned to three treatments: (1) low fish oil (LFO), basal diet + 2% fresh fish oil; (2) high fish oil (HFO), basal diet + 8% fresh fish oil; and (3) oxidized fish oil (OFO), basal diet + 8% OFO (peroxide value = 250 meqO2kg−1). Pigs fed HFO and OFO diets showed yellow staining of fat and decreased growth performance, including average daily gain, average daily feed intake, and final body weight (P

Genes participating in the changes of yolk lipids by unsaturated oils remain elusive. In this study, ducks were randomly assigned to 3 groups, fed with basal-diet (C), basal-diet-plus-2%-flaxseed-oil (FL), or basal-diet-plus-2%-fish-oil (F), respectively. A digital-gene-expression-profiling analysis of livers were performed after four weeks. Compared to C, 36 and 25 differently-expressed-genes (DEG) were identified in FL and F, respectively. These genes participated in lipid metabolism pathways. In both F and FL, the sterol 12 α-hydroxylase 1 gene was down regulated, as well as the fatty acid synthase gene and stearoyl-CoA desaturase gene. In FL, the fatty acid desaturase 2 gene (FADS2) and elongation of the very long-chain fatty acids protein 2 gene (ELOVL2) were up regulated, and the CYP2U (cytochrome P450, family 2, subfamily U) was down regulated. However, the FADS2 and ELOVL2 were down regulated in F to possibly prevent the redundancy of body n-3 PUFAs. In conclusion, FL and F had different molecular pathways to reduce yolk cholesterol and increase n-3 PUFAs. However, CYP8B1 and FADS2 were the key genes in the regulation of both of them. α-linolenic acid in the FL might be transformed to longer n-3 PUFAs. In addition, this study adds sequence information to duck.

The occurrence of cryoinjuries during ovarian tissue freezing necessitates development of methods that can overcome these challenges in cell and tissue cryopreservation. It has been hypothesized that omega-3 and vitamin E diet supplementation to the animal could be an appropriate strategy to preserve post-thaw ovarian quality. The laying hen is an appropriate animal model that can be used to study the effects of providing dietary supplements on the outcomes of ovary cryopreservation. The purpose of the study was to evaluate the dietary effects of fish oil, sunflower oil, and vitamin E on 68 laying hens according to the following treatments: basal diet + 1.5% sunflower oil (control; C); basal diet + 1.5% sunflower oil + 1.1 IU alpha-tocopherol/hen/day (E); basal diet + 1.5% fish oil + 1.1 IU alphatocopherol/hen/day (n-3+E); and basal diet + 1.5% fish oil (n-3). The effects on ovarian structure and preservation, apoptosis-related gene expression, and the fatty acid profiles in ovarian laying hen (n = 7 in each group) were studied. The number of intact primordial follicles in n-3+E group was significantly higher than other groups (85% vs. 71%, 72%, and 77% for n-3+E, C, E, and n-3, respectively; p 0.01). There was a significant reduction in expression of Cas3, as well as Cas8, in n-3 and n-3+E than C and E (p ≤ 0.05). A trend to decrease in Bak (p = 0.089) and Bak/Bcl2 ratio (p = 0.095) in the mRNA was observed in n-3+E. Ovarian eicosapentaenoic acid (C20:5n3) concentration in n-3 was the highest among C, E, and n-3+E (p 0.01). Docosahexaenoic acid (C22:6 n-3) concentrations in ovaries of the n-3 group were elevated five times more than control. The n-3: n-6 ratio in groups receiving omega-3 (n-3+E and n-3) was higher than other groups (p 0.01). In conclusion, consumption of dietary omega-3 fatty acids with vitamin E improves the results of vitrification of ovarian tissues in laying hens.

Dietary fish oil supplements containing the omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are frequently used for cardiovascular benefit. However, several factors may limit the intake of prescribed doses.The objective of this study is to compare the prescribed, patient self-reported, and actual intake of supplemental EPA + DHA doses in a lipid-specialty clinic and identify common barriers and influences to therapy.Seventy-six patients prescribed supplemental fish oil were randomly selected to participate in a 28-item cross-sectional survey for evaluating patient knowledge and intake of prescribed supplemental EPA + DHA doses. Self-reported data were collected during a follow-up clinic visit, whereas actual intake was determined when patients had access to their fish oil bottle. These data were compared with their chart-documented prescribed EPA + DHA dose.Many patients were well-educated and had attended the lipid-specialty clinic for approximately 2 years but only 28.9% were confident that they could accurately recall their daily EPA + DHA dose. There were statistically significant differences between the prescribed doses and patients' self-reported doses (3600 mg vs 2750 mg, P = .014), as well as between prescribed doses and actual intake (3600 mg vs 1575 mg, P .001). Patients reported multiple barriers and influences to explain their use of fish oil products.Most patients using supplemental fish oil in a lipid-specialty clinic were not taking the prescribed amount of EPA + DHA, with many using markedly lower than prescribed doses. This is likely because of several factors including the complexities of supplemental fish oil doses and labeling, product availability, and discount sales. These findings suggest that supplemental fish oil requires continuous education and dosing guidance.

The present study investigated the effects of total replacement of dietary fish oil by different vegetable oils on growth performance, nutritional quality and fatty acid profiles of rainbow trout (Oncorhynchus mykiss) at optimum -and high temperature conditions. Five iso-nitrogenous and iso-lipidic diets including 100% fish oil and vegetable oils were prepared for rainbow trout fingerlings with an average weight of 11.27±0.01 g. After the fish were fed experimental diets for 9 weeks at the optimum temperature (17.74 ± 0.01 ° C), all groups were fed an FO diet containing only fish oil for 4-weeks at the upper optimum temperature conditions (19.28 ± 0.11°C). In both feeding trials, experimental fish were hand-fed ad libitium twice a day. Results showed that growth performance and feeding efficiency were significantly better (p, Bu çalışmada, balık yağının farklı bitkisel yağlarla toplam ikamesinin, optimum ve yüksek sıcaklık koşullarında gökkuşağı alabalığının (Oncorhynchus mykiss) büyüme performansı, beslenme kalitesi ve yağ asidi profilleri üzerindeki etkileri araştırılmıştır. Ortalama 11.27 ± 0.01 g ağırlıktaki gökkuşağı alabalığı yavruları için %100 balık yağı ve bitkisel yağlardan oluşan beş izo-nitrojenli ve izo-lipidik diyet hazırlanmıştır. Balıklar optimum sıcaklıkta (17.74±0.01°C) 9 hafta deneysel diyetlerle beslendikten sonra, tüm gruplara optimum üstü sıcaklık koşullarında (19.28±0.11°C) 4 hafta boyunca sadece balık yağı içeren bir FO (kontrol) diyeti verilmiştir. Her iki besleme denemesinde de deneysel balıklar günde iki kez elle doyuncaya kadar beslenmiştir. Sonuçlar, optimum sıcaklıkta FO bazlı diyetle beslenen gruplara kıyasla, VO bazlı diyetlerle beslenen gruplarda büyüme performansı ve yemleme veriminin önemli ölçüde daha iyi (p

Here, we investigated the effects of total dietary fish oil (FO) substitution with plant oil (PO) on hematological indices, immune status, antioxidant activity, IL1β and TNF-α gene expression, and hypoxia stress resistance in Oreochromis niloticus at suboptimal temperatures. Fish (n = 360) were randomly divided into 12 circular fiberglass tanks (500 L; 3 replicates for each dietary group, 30 fish/replicate, 90 fish/group). The control group was fed a basal diet with FO as the lipid source. The CO, SFO, and LSO groups were fed a basal diet with complete replacement of FO with corn, sunflower, and linseed oils, respectively. After 4 weeks, no effects on hematological indices were observed in fish fed the experimental diets. The LSO and CO groups showed a significant increase in γ globulin levels. The highest levels of non-specific immune parameters, antioxidant activity, and IL-1β and TNF-α gene expressions were recorded in the LSO group. The LSO group also exhibited good resistance to hypoxia stress. Therefore, the total dietary substitution of FO with PO (especially LSO and CO) is recommended as a valuable strategy to ameliorate the immunosuppressive effects of suboptimal temperatures and enhance the resistance of O. niloticus to hypoxia stress.

The aim of this study was to evaluate the effect of feeding oil supplement on mammary gland development and milk production responses in Holstein cows. Ten multiparous Holstein cows (42.2±9.2 d before calving, 3.25±0.25 body condition score, and 620±35 kg body weight) were randomly assigned to treatments. Treatments were a diet with oil added as palm oil (PO; n=5), or fish oil (FO; n=5) given to cows until 63 d in milk. Milk yield was recorded daily, milk composition (fat, protein, lactose, total solid and somatic cell count) was measured weekly and fatty acid profiles of milk fat were determined at first and last week of the experiment. Samples of mammary tissue were obtained at 7 and 63 d in milk by biopsy gun. Tissue slides were analyzed by Image J software. Results showed that fish oil supplemented diet compared to the palm oil supplemented diet increased milk production after 6 weeks of lactation (Pn-6:n-3 ratio was decreased by fish oil supplement (P

Contusion injury in aging muscle has not been studied in detail, but older adults are at risk for such injuries due to increased risk of falls. As falls in older populations are unlikely to be eliminated, interventions to minimize the negative impact of falls, including contusion injury should be pursued. Dietary fish oil (FO) is a common often supplement in older adults, which is associated with factors that might reduce or worsen the negative impact of contusion.Here, we investigate whether 8 weeks of FO can blunt the impact of contusion injury in adult (n = 14) and aged (n = 12) rats. We assessed contractility and several biochemical markers in adult and aged gastrocnemius muscles 48 h post-contusion injury, using the uninjured muscles as controls.Injury reduced force production ~40% (P 0.001), sarcoplasmic reticulum calcium release by ~20% (P = 0.003) and significantly increased several markers of muscle damage (i.e., protein carbonyls, Grp78 abundance (P = 0.022, 0.006, respectively)), and these injury-related changes were not affected by aging. The effects of FO were limited. A main effect (P = 0.018) for FO to increase the myogenic factor Myf5 was observed. In addition FO reduced the injury-associated decline in the mitophagy factor DRP1 (P = 0.027).Although age-related differences in certain protein markers differed, aged muscles exhibited no greater acute functional deficits following injury. Similarly, while FO did not reduce functional deficits, it did not worsen them. However, changes in Myf5 and DRP1 with dietary FO suggest the potential to improve recovery from contusion injury, which should be investigated in future studies.

Diets high in unsaturated fatty acids, especially those containing high levels of linoleic acid, e.g., corn oil, enhance mammary gland tumorigenesis in experimental animals. In contrast, diets high in long-chain polyunsaturated fatty acids such as eicosapentaenoic (EPA) and docosahexaenoic (DHA), e.g. menhaden oil, appear to have a suppressive effect on this tumorigenic process. Many mechanisms have been proposed to explain the tumor inhibitory action exerted by menhaden oil and other fish oils, e.g., differences in prostaglandin metabolism, energy efficiency, alterations of the immune system, changes in lipid peroxidation, etc. Fundamental to a mechanistic understanding of this phenomenon, however, is an understanding as to whether or not the tumor inhibitory activities of dietary fish oil is mediated via an inhibition of tumor cell proliferation or mediated via an enhancement of tumor cell loss. Whether the amount of dietary fat or the type of fat effects mammary tumorigenic processes, via an effect on tumor cell proliferation or tumor cell loss, has not been clearly established. In the studies described in this communication, three methods were utilized to study tumor cell proliferation, i.e., H3-thymidine autoradiographic analysis, 5-bromo 2'-deoxyuridine (Brdu) flow cytometric analysis, and proliferative cell nuclear antigen (PCNA) flow cytometric analysis. Two methods were used to study tumor cell loss, i.e., a determination of the I125Urd tumor emission rate and a determination of a cell loss factor from the formulas of Steel and Begg. The tumor examined was the human breast carcinoma cell line MDA- MB231 maintained in athymic nude mouse. No significant difference in cell proliferation between carcinomas of mice fed a high corn oil diet (20% w/w) and a diet high in fish oil (19% menhaden oil, 1% corn oil). In contrast, a significant (p

OBJECTIVES: Several epidemiological studies have examined the association between fish and dietary fish oil intake and metabolic syndrome in a population. However, few studies have investigated fish and dietary fish oil intake and its association with the risk of metabolic syndrome in the Korean population. METHODS: Using data from the 2013–2016 Korea National Health and Nutrition Examination Survey, a total of 14,519 adults (6,135 men and 8,384 women) aged ≥ 19 years were involved in this study. Dietary intakes of fish and fish oil including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were estimated by a 24-h dietary recall. Metabolic syndrome was diagnosed using the National Cholesterol Education Program Adult Treatment Panel III criteria. The odds ratios (ORs) for the presence of metabolic syndrome according to the tertile of fish and fish oil intakes were calculated using a multiple logistic regression model. RESULTS: The prevalence of metabolic syndrome among the participants was 9.18%. The mean intake (standard error, SE) of fish, EPA and DHA was 123.35 (2.67) g/day, 103.43 (2.48) mg/day and 179.21 (4.75) mg/day for the study participants, respectively. Dietary intakes of fish and fish oil were not associated with the prevalence of metabolic syndrome, however, they were associated with the prevalence of several metabolic abnormalities. Men in the highest tertile of energy adjusted DHA intake from fish showed a 20% decreased risk of hypertriglyceridemia (OR, 0.80; 95% CI, 0.67–0.96, p for trend, 0.0274), compared with those in the lowest tertile. However, Women in the highest tertile of fish intake showed a higher prevalence of impaired fasting glucose (OR, 1.70; 95% CI, 1.24–2.33) than those in the lowest tertile. CONCLUSIONS: Our findings suggest that a higher intake of dietary fish oil might be associated with a lower risk of hypertriglyceridemia in Korean men. Thus, further prospective studies are needed to examine the association of fish and fish oil with metabolic syndrome. FUNDING SOURCES: This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (NRF-2018R1A2B6007070) and the National Institute of Fisheries Science (R2019051).

Here, the potential mechanisms of the protective effects of fish oil against LPS-induced liver injury in a piglet model were investigated by using RNA sequencing. Twenty-four piglets were used in a 2 × 2 factorial design, and the main factors included diet (5% corn oil or 5% fish oil) and immunological challenge (LPS or saline, on d 19). All piglets were slaughtered at 4 h after challenge, and liver samples were collected. Fish oil improved liver morphology and reduced TNF-α, IL-1β and IL-6 productions after LPS challenge. RNA sequencing analysis showed fish oil had significant effect on the expressions of genes involved in immune response during LPS-induced inflammation. Selected gene expression changes were validated using quantitative RT-PCR. Fish oil reduced the expressions of pro-inflammatory genes IL1R1, IL1RAP, CEBPB and CRP, and increased that of anti-inflammatory genes IL-18BP, NFKBIA, IFIT1, IFIT2 and ATF3. Moreover, fish oil restored the expressions of some lipid metabolism-related genes, such as ACAA1, ACACA, ACADS and ACADM, which were only decreased in pigs fed a corn oil diet after LPS challenge. Our RNA sequencing reveals novel gene-nutrient interactions following fish oil supplementation and evoked inflammation, which add to the current understanding of the benefits of n-3 polyunsaturated fatty acids against liver injury.

The aim of this study was to elucidate the effect of dietary fish oil (FO) and a blend of FO and hydrogenated palm oil (FOPO) on transport of fatty acids (FA) within plasma lipoproteins in lactating and non-lactating cows. Two trials were conducted (one with lactating and another with non-lactating dairy cows) in two 3 × 3 Latin squares that included three periods of 21 days. Dietary treatments for lactating cows consisted of a basal diet (Control; no fat supplement), and fat-supplemented diets containing FO (500 g/day/cow) and FOPO (250 FO + 250 g/day/cow hydrogenated palm oil). For non-lactating cows, dietary treatments consisted of a basal diet (Control; no fat supplement), and fat-supplemented diets containing FO (170 g/day/cow) and FOPO (85 FO + 85 hydrogenated palm oil g/day/cow). In lactating cows, compared with control and FOPO, FO increased C16:0, C18:3 cis-9, 12, 15, C18:2 cis-9, trans-11 and total saturated and polyunsaturated FA in plasma and increased C16:0, C18:2 cis-9, trans-11, total polyunsaturated and total polyunsaturated n-6 in high-density lipoprotein (HDL), whereas in non-lactating cows, compared with control and FOPO, FO increased C16:0, C18:1 trans-11, C18:2 trans-9, 12, C18:2 cis-9, trans-11, C20:5 n-3 and total saturated and polyunsaturated FA in plasma; C16:0, C18:1 trans-11, C18:1 cis-9, C18:2 trans-9, 12, C20:5 n-3 and total monounsaturated FA in HDL; and C18:1 trans-6-8, C18:1 trans-9, C18:1 trans-10, C18:1 trans-11, C18:3 cis-9, 12, 15 and C20:5 n-3 in low-density lipoprotein (LDL). FO increased C20:5 n-3 in plasma and lipoproteins in non-lactating cows and increased C18:3 cis-9, 12, 15 in plasma (in lactating cows) and LDL (in non-lactating cows). We concluded from results of this study that in bovine plasma, the LDL fraction appears to be the main lipoprotein transporting C18:1 trans isomers and is more responsive than other lipoprotein fractions to variation in supply of dietary lipids.

Identifying suitable alternatives to fish oil for inclusion in formulated diets for aquaculture species is becoming increasingly important; however, relatively few studies have assessed the potential of terrestrial oils as possible replacements for fish oil in diets for marine crustaceans. This study examined the potential of soybean oil as a partial or complete replacement for fish oil in diets for blue swimmer crab Portunus pelagicus juveniles. Seven iso-nitrogenous and iso-lipidic diets were formulated to contain soybean oil to fish oil ratios of 1:0. 3:1. 2:1. 1:1. 1:2. 1:3. and 0:1. They were fed to first-stage crabs over four molts and survival, development, and growth of the crabs were measured. Crabs fed the diet containing soybean oil as the sole lipid source (i.e., soybean oil:fish oil ratio 1:0 treatment) recorded the lowest survival among treatments, significantly longer intermolt duration, and significantly lower specific growth rates compared with other treatments. Improved performance was shown by crabs fed diets containing fish oil at the same, or higher, dietary level than soybean oil but the best survival, shortest intermolt duration, and fastest growth rates were recorded for crabs fed the diet containing the soybean oil:fish oil ratio of 1:1. The results indicated that P. pelagicus juveniles require a balance of dietary n-3 and n-6 fatty acids and thus dietary lipid requirements can be met partially by soybean oil. Diets containing soybean oil are cheaper to produce than traditional fish oil—based diets and soybean oil is a more sustainably sourced ingredient than fish oil. Our results should support further development of the P. pelagicus aquaculture industry.

The objective was to evaluate the effects of dietary fish oil (FO) and vitamin E (VE) supplementation on sperm sensitivity to lipid peroxidation (LP) in dogs. Using an incomplete replicate 3 × 3 Latin square design, five dogs were allocated into three groups. One of the squares was incomplete and had two dogs that were used with three treatments. The dogs were assigned to three different treatments, fed a control diet of balanced commercial food (control group; CG), control diet supplemented with 54 mg FO/kg body weight0·75 per d (FO group; FG) and FO plus 400 mg VE per d (FO and VE group; FEG) for 60 d. Semen samples were collected on days 0 and 60 and divided into two halves, peroxidised and control, with or without ascorbate–Fe2+, respectively. LP was measured in both halves by chemiluminescence as counts per min/mg protein. Fatty acid profile was determined by GC. Data were analysed using the mixed procedure (SAS). On day 0, LP increased in all groups in the peroxidised samples (P < 0·05). However, on day 60 LP decreased in peroxidised samples of both the FG and FEG (P < 0·05), but there were no differences between the FG and FEG (P > 0·1). Additionally, on day 60 total n-3 was higher in the FG and FEG compared with the CG (P < 0·05). Supplementation with FO alone or together with VE decreased LP in peroxidised samples. These results could indicate a protective effect of n-3 on sperm. More studies are needed to understand the mechanism whereby FO and/or FO plus VE decrease LP in dogs’ sperm., Facultad de Ciencias Veterinarias, Instituto de Genética Veterinaria

The aim of this study was to evaluate the effect of fish oil added to feed mixtures for geese on their growth, lipid profile and antioxidant status of leg muscles. Ninety-six Arzamas geese were randomly divided into two groups and fed from 30 to 60 days of life standard mixtures containing soybean oil (control) or fish oil at 5%. The addition of fish oil to the feed mixtures for geese increased the content of EPA and DHA, and decreased the ratio of n-6 to n-3 fatty acids in fat of breast muscles compared to birds fed the control mixture. It also resulted in a considerable increase in the content of phospholipids and decreased the content of glycerol, free fatty acids as well as triacylglycerols and esterified cholesterol. The type of fat source had no effect on the content of lipid peroxidation products and the activity of antioxidant enzymes.

Studies in the literature describe the ability of dietary supplementation by omega-3 fish oil to increase the pumping efficiency of the left ventricle. Here we attempt to reconcile such studies with our own null results. We undertake a quantitative analysis of the improvement that could be expected theoretically, subject to physiological constraints, by posing the following question: By how much could efficiency be expected to increase if inefficiencies could be eliminated? Our approach utilizes thermodynamic analyses to investigate the contributions, both singly and collectively, of the major components of cardiac energetics to total cardiac efficiency. We conclude that it is unlikely that fish oils could achieve the required diminution of inefficiencies without greatly compromising cardiac performance.

A substituição do óleo de peixe em dietas para beijupirá (Rachycentron canadum) foi avaliada usando-se cinco proporções de óleo de peixe e soja. Duzentos juvenis (±12g) foram distribuídos aleatoriamente em 20 tanques e alimentados até a saciedade aparente durante 42 dias. À medida que se aumentou o teor de óleo de peixe nas dietas, houve aumento proporcional no desempenho. Os juvenis alimentados com dietas que continham 75 e 100% de óleo de peixe apresentaram ganhos de peso mais altos que os das dietas com 0 e 25% de óleo de peixe, enquanto os alimentados com a dieta com 50% de óleo de peixe apresentaram crescimento intermediário. Não foram observadas diferenças nas concentrações de proteína e lipídio na carcaça dos peixes, mas os teores de umidade e cinzas diferiram entre os tratamentos. A inclusão de teores relativamente altos de ingredientes de origem vegetal diminuiu o consumo alimentar, o que afetou negativamente o crescimento. Os resultados indicam a possibilidade de substituição de até 50% do óleo de peixe por óleo de soja em dietas para juvenis do beijupirá. The replacement of fish oil for cobia (Rachycentron canadum) in diets was evaluated using five proportions of fish oil:soybean oil. Two hundred juveniles (±12g) were randomly distributed in twenty 480L tanks and fed to apparent satiety twice daily for 42 days. Diets contained 12% lipids with different proportions of fish to soybean oils and were therefore named OP0, OP25, OP50, OP75 and OP100 according to the inclusion content of fish oil (0, 25, 50, 75 and 100%, respectively). Increasing dietary fish oil levels resulted in higher survival, growth and feed intake. Fish fed diets OP75 and OP100 presented higher weight gain than those fed diets OP0 and OP25, whereas fish fed diet OP50 had an intermediate weight gain. Overall, performance was enhanced at higher contents of dietary fish oil. No significant differences on protein and lipid content of fish carcass were observed, but moisture and ash content differed significantly between treatments. The inclusion of relatively higher contents of plant ingredients affected feed intake, which resulted in lower growth rates. The present results suggest the possibility of replacing up to 50% of fish oil with soybean oil in diets for cobia juveniles.

Considerable feed savings may be realized by reducing the fish oil (FO) content of aquafeeds used during grow-out, but fatty acid (FA) profile of the resultant seafood will be altered. By feeding a FO-rich finishing feed prior to harvest, fillet levels of beneficial long-chain polyunsaturated FA (LC-PUFA) can be partially or completely restored. We evaluated the use of linseed oil (LO) as a partial substitute for FO, and assessed the relative impacts of grow-out feed FO concentration and finishing duration on production performance and fillet fatty acid (FA) composition of sunshine bass. Fish were raised on feeds containing 33 or 67% FO during the grow-out period, and then finished with a 100% FO finishing feed for 4 or 8 weeks before harvest; for comparison, a control group was fed the 100% FO feed throughout the entire 20-week trial. Production performance was unaffected by the dietary formulations or feeding schemes, however, fillet FA varied among treatment groups. Increased consumption of LO, whether by increased dietary concentrations or longer feeding periods, resulted in elevated levels of LO-associated medium-chain polyunsaturated FA, specifically 18:3n-3; increased consumption of FO had the same effect on tissue levels of FO-associated LC-PUFA such as 20:5n-3 and 22:6n-3. Finishing had a significant restorative effect on fillet LC-PUFA content (LC-PUFA in finished groups ranged from 64-87% of control levels compared to 50-71% in unfinished groups), however, with the exception of 22:6n-3, 8 weeks of finishing was still insufficient to completely restore fillet LC-PUFA content to control levels, regardless of grow-out feed. We observed fillet levels of LC-PUFA to be essentially a function of total FO consumption, and FA profile change to be relatively well-described by simple dilution modeling. However, further research is needed to unequivocally demonstrate the relative merits of continuous vs. periodic provision of FO-rich aquafeeds.