The effect of replacing dietary fish oil with canola oil on fatty acid composition and expression of desaturase and elongase genes in Jade Tiger hybrid abalone

This study investigates the effect of graded substitution of dietary fish oil (FO) with canola oil (CO) on fatty acid composition and expression of Δ-6 desaturase and elongase 2 genes in the muscle of Jade Tiger hybrid abalone. The control diet contained 1.5% FO supplement (0% CO). Four other diets contained FO/CO in ratios of 3:1 (CO 25%), 1:1 (CO 50%), 1:3 (CO 75%) and 100% CO. The result demonstrated that abalone fed the diets supplemented with 25% and 50% CO showed similarly high levels of total omega-3 polyunsaturated fatty acid (n-3 PUFA), eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) (P < 0.05) as the 0% CO group. The highest levels of total PUFA and total monounsaturated fatty acids were found in the 100% CO group (P < 0.05). The results also showed that Δ-6 desaturase and elongase 2 gene expression was increased in a graded manner by increasing dietary CO (P < 0.05). It was concluded that replacement of FO by CO at the levels of 25-50% can improve the contents of health-benefiting EPA and DHA in abalone.     

The impact of dietary oil source and frozen storage on the physical,chemical and sensorial quality of fillets from market-size red hybrid tilapia, Oreochromis sp.

Red hybrid tilapia (Oreochromis sp.) were fed one of four diets containing either fish oil, crude palm oil, palm fatty acid distillates or refined palm olein as the only added oil. Post-harvest fillet quality was then evaluated at 1, 10 and 30 weeks of frozen storage. Dietary oil source did not significantly (p > 0.05) influence the liquid holding capacity and texture of fillets but both these parameters were increased by frozen storage. Fillets from fish fed palm oil-based diets exhibited significantly higher oxidative stability during frozen storage, compared to fish fed the fish oil diet. Dietary oil source and frozen storage had little impact on sensory attributes. Unlike fillet proximate composition, fillet fatty acid composition was significantly affected by both diet and frozen storage. Total n-3 polyunsaturated fatty acids decreased significantly in the fillet lipids of all fish after 30 weeks of frozen storage.     

Animal performance and fatty acid composition of lambs fed with different vegetable oils

Twenty-seven lambs were used to investigate the effects of the inclusion of 4% hydrogenated palm oil (HPO) or sunflower oil (SFO) in the concentrate on animal performance, carcass and meat quality and fat characteristics and fatty acid composition. Animals (16.2 ± 0.27 kg initial weight) were fed concentrate (Control, HPO or SFO) and barley straw ad libitum and slaughtered at 25 kg. SFO lambs tended to eat less concentrate than HPO animals (P < 0.10). Neither HPO nor SFO affected any of the carcass characteristics studied, meat pH and meat and fat colour (P > 0.05). SFO decreased proportions of C16:0, C18:1 cis-11 and C18:3 (P < 0.05) and increased C18:1 trans (P < 0.001) and C18:2/C18:3 ratio (P < 0.05). Atherogenicity index was lower (P < 0.05) when SFO was included in the concentrate. HPO did not affected and SFO improved fatty acid composition of fattening lambs without affecting animal performance.     

Meat quality parameters of descendants by grading hybridization of Boer goat and Guanzhong Dairy goat

Chemical composition, cholesterol levels, fatty acid profile, meat taste, and quality parameters were evaluated in 48 buck kids from goats of the Guanzhong Dairy breed (Group G) and their crosses (Group F1: 1/2 Boer♂ × 1/2 Guanzhong Dairy♀; Group F2: 3/4 Boer♂ × 1/4 Guanzhong Dairy♀; Group F3: 7/8 Boer♂ × 1/8 Guanzhong Dairy♀) at different ages of slaughter (6, 8 and 10 months). Results indicated that grading hybridization (P < 0.05) affected meat nutritive value. The muscle of hybrid goats had lower crude fat and cholesterol, higher crude protein, and greater proportion of C18:2 and C18:3 than that of Group G at each age. Group F1 goats had better (P < 0.05) desirable fatty acid (DFA) and polyunsaturated fatty acid (PUFA) to saturated fatty acid (SFA) ratios and greater (C18:0 + C18:1/C16:0) ratios (P < 0.01) than those of the other genotypes. Furthermore, the muscles of hybrid goats were tenderer and juicier compared to Group G. In all four groups, cholesterol levels increased (P < 0.01), muscle color became redder (P < 0.05) and tenderness decreased (P < 0.05) with increasing age. The low level of lipids and cholesterol, good meat quality, and the higher ratio of unsaturated to SFA in Group F1 indicate better quality for human consumption.     

Chemical composition characteristics of the longissimus and semimembranosus muscles for pigs from New Zealand and Singapore

A range of composition characteristics of the longissimus (LL) and semimembranosus (SM) muscles were compared between pigs raised in intensive and extensive production systems in New Zealand (NZ), and pigs raised in an intensive system in Indonesia for supply to the Singapore market (n = 8/group). Ultimate pH was slightly higher for the Singaporean LL muscles (P < 0.05), while LL muscle of the NZ extensive group was redder (higher a^∗ values) and contained more fat (P < 0.05). Muscle iron levels were highest for the NZ extensive group and lowest for a lighter group within the Singapore pigs (P < 0.05). Differences in fatty acid concentrations, which were also measured in a sample of the belly cut, could largely be attributed to the effects of diet, with higher levels of alpha linolenic acid for the NZ extensive group (P < 0.05) due to linseed in the diet, and much higher levels of linoleic acid and the P:S ratio for the Singapore group (P < 0.05). Some statistically significant differences in amino acid concentrations were shown between muscles and groups, but they were not large. With respect to compounds with potential bioactive properties, coenzyme Q_10, and taurine levels were higher in pork from NZ pigs, and carnosine levels were highest for the NZ intensive group (P < 0.05). The LL muscle contained more coenzyme Q₁₀ and taurine, but less carnosine than the SM muscle (P < 0.001). It is concluded that some of these composition differences in the pork from the muscles and groups compared may be of commercial importance, but several are likely to have been due to dietary or weight differences.     

Low-fat frankfurters enriched with n−3 PUFA and edible seaweed: Effects of olive oil and chilled storage on physicochemical,sensory and microbial characteristics

This article reports a study of the physicochemical, sensory and microbiological characteristics of low-fat (10%) and n−3 PUFA-enriched frankfurters as affected by addition of seaweed (5% Himanthalia elongata), partial substitution (50%) of animal fat by olive oil and chilled storage (41 days at 2 °C). The presence of seaweed improved water and fat binding properties, reduced (P < 0.05) lightness and redness and increased (P < 0.05) the hardness and chewiness of low-fat frankfurters enriched with n−3 PUFA. The effect of olive oil on those characteristics was less pronounced than that of seaweed. Replacing pork backfat with olive oil in frankfurters produced acceptable sensory characteristics, similar to control, while addition of seaweed resulted in less acceptable products, due mainly to the special flavour of the seaweed. Formulation and storage time affected the total viable count and lactic acid bacteria count. Frankfurters containing olive oil and seaweed had the highest total viable count from day 14 of storage, with lactic acid bacteria becoming the predominant microflora.     

Conjugated linoleic acids content in M.longissimus dorsi of Hanwoo steers fed a concentrate supplemented with soybean oil,sodium bicarbonate-based monensin,fish oil

We hypothesized that increasing ruminal pH would lead to enrichment of adipose tissue with conjugated linoleic acid (CLA). Twenty-four Korean native (Hanwoo) steers were used to investigate the additive effects of monensin (30 ppm, SO-BM) and/or fish oil (0.7%, SO-BMF) in the diets along with soybean oil (7%) and sodium bicarbonate (0.5%, SO-B) on cis-9, trans-11 and trans-10, cis-12 CLAs in adipose tissue. The steers were assigned to randomly four groups of six animals each based on body weight. The control group (CON) was fed a commercial concentrate for the late fattening stage. Supplementation of oil and sodium bicarbonate reduced feed intake and daily gain, and fish oil further decreased feed intake (P < 0.001) and daily gain (P < 0.087) compared to steers fed other diets. Total CLA and CLA isomers in M.longissimus dorsi were not affected when steers were fed SO-B and SO-BM diets compared with those of steers fed CON and SO-BMF diets. However, total poly unsaturated fatty acids were higher (P = 0.03) in steers fed SO than in CON steers.     

Lipid and colour stability of M. longissimus muscle from lambs fed camelina or linseed as oil or seeds

Colour and lipid stability of M. longissimus dorsi (LD) from sheep fed diets containing different lipid sources (Megalac (MG), camelina oil (CO), linseed oil (LO), NaOH-treated camelina seed (CS), NaOH-treated linseed (LS) or CO treated with ethanolamine (CA)) were examined. After 100 days on-feed, samples of LD were collected, fatty acid profile determined and colour and lipid oxidation (2-thiobarbituric acid reactive substances; TBARS) measured during retail display in high oxygen packaging. The LS ration was most effective in increasing the 18:3n − 3 and conjugated linoleic acid (CLA) concentration in muscle. Within camelina, CA resulted in the highest 18:3n − 3 and lowest CLA concentration in muscle. There was no difference in colour stability. Oil (seed) supplementation increased TBARS compared to MG in the early part of display while linseed-based rations tended to cause higher TBARS than camelina-based rations. Higher muscle 18:3n − 3 concentration was associated with higher oxidation during early retail display but this was not reflected in a loss of colour stability.     

Effect of dietary inclusion of triticale dried distillers' grain and oilseeds on quality and fatty acid profile of meat from feedlot steers

This study compared carcass, meat quality and fatty acid profiles of longissimus thoracis (LT) from feedlot cattle fed barley grain with or without oilseed (OS). Six diets containing no oilseed (No-OS), 10% ground flaxseed (FS), 10% high oleate sunflower seeds (SS) with or without 30% triticale dried distiller's grain (DDGS) were prepared. Feeding DDGS increased chroma at 24 and 144 h post mortem. Feeding FS increased weight% of LT PUFA (P < 0.05) compared to No-OS or SS. An OS by DDGS interaction occurred for 18:3n − 3 (P < 0.05) where FS increased weight% of 18:3n − 3 (P < 0.05), a response accentuated (P < 0.05) by DDGS. Feeding DDGS increased weight% of LT 18:2n − 6 (P < 0.05), but neither OS nor DDGS affected conjugated linoleic acid (CLA, t7,c9 & c9,t11-18:2). Feeding FS increased weight% of n − 3 FA, and both FS and SS increased t10-18:1 with no effect on CLA or t11-18:1. Combination feeding of DDGS and FS further increased weight% of n − 3 FA and tempered increases in t10-18:1 with no effect on CLA or t11-18:1. The findings suggest a new strategy to increase beef omega-3 fatty acids efficiently through inclusion of a combination of DDGS and FS in feedlot diet.     

Anti-hyperlipidaemic and antioxidant effects of turmeric oil in hyperlipidaemic rats

This study was to evaluate the anti-hyperlipidaemic and antioxidant effects of turmeric oil (TO), the supercritical fluid extract from turmeric, in hyperlipidaemic rats induced by a high-fat diet. TO significantly decreased (p < 0.05) the levels of serum total cholesterol, low-density lipoprotein cholesterol, triglyceride, and free fatty acid and increased (p < 0.05) that of high-density lipoprotein cholesterol in this model. It also markedly elevated (p < 0.05) the activities of superoxide dismutase and glutathione peroxidase and lowered (p < 0.05) maleic dialdehyde activity, to suppress oxidative reactions. Besides, histological morphology examination showed that TO prevented the damage of liver tissues induced by high-fat diet. Thus, the findings indicate that TO might provide protection against cardiovascular diseases.     

Effects of dietary flaxseed oil on cholesterol metabolism of hamsters

High-fat/cholesterol diets (HFCD) formulated by addition of butter (BU), coconut oil (CO), or flaxseed oil (FX) enhanced (P < 0.05) serum lipids of hamsters compared to the low-fat/cholesterol diet (Control). However, FX groups showed a hypocholesterolaemic effect compared to CO and BU groups. Lower (P < 0.05) hepatic triacylglycerol and cholesterol contents were measured in FX groups than those of CO and BU groups; whereas, higher (P < 0.05) faecal triacylglycerol and cholesterol contents were observed in FX groups. HMG-CoA reductase mRNA expression was upregulated (P < 0.05) by HFCD, whilst FX groups showed no (P > 0.05) influence on LDL-receptor mRNA expression compared to that of Control groups; however, higher (P < 0.05) than those of CO and BU groups. Meanwhile, there was a tendency towards higher CYP7A1 expression in the CO or FX group than the BU group. Thus, the hypocholesterolaemic effect of FX might result from increases of LDL-receptor mRNA expression, and cholesterol catabolism/output.     

Effect of ractopamine–HCl supplementation for 28 days on carcass characteristics,muscle fiber morphometrics,and whole muscle yields of six distinct muscles of the loin and round

This study evaluated the effects of ractopamine–HCl (RAC) supplementation on carcass characteristics, muscle fiber morphometrics, and tenderness. Thirty-four steers (2 groups, 4 replicates) were fed RAC or carrier for 28 days prior to harvest. Seventy-two hours postmortem, the Longissimus lumborum (LL), Gracilis (GRA), Vastus lateralis (VL), Rectus femoris (RF), Semimembranosus (SM), and Adductor (ADD) were dissected from each carcass. Commodity weight, denuded weight, and muscle dimensions were collected. RAC supplementation tended to affect dressing percentage (P = 0.15) and muscle firmness (P < 0.15), and significantly affected lean maturity (P < 0.05) and marbling score (P < 0.05). With the exception of the LL and GRA (P < 0.05), RAC had no effect on muscle dimensions. RAC did not influence the tenderness of vacuum-packaged, aged steaks as measured by Warner–Bratzler shear force. Muscle fiber size within the six muscles was unchanged (P > 0.05) by RAC. Thus, RAC improves carcass parameters without a negative impact on tenderness.     

Round scad protein-based film: Storage stability and its effectiveness for shelf-life extension of dried fish powder

Storage stability of different round scad (Decapterus maruadsi) protein-based films including (1) control film without palm oil and chitosan, (2) film with 25% palm oil (glycerol substitution) and (3) film with 25% palm oil and 40% chitosan (protein substitution) was investigated. During storage (54% relative humidity, 28-30 °C), tensile strength (TS) of the films without and with 25% palm oil or 25% palm oil in combination with 40% chitosan increased continuously, while elongation at break (EAB) decreased markedly when storage time increased up to 8 weeks (p < 0.05). No changes in water barrier properties were observed throughout the storage time up to 4 weeks (p > 0.05). Film solubility slightly increased but protein solubility decreased continuously during storage (p < 0.05). All films became darker and more yellowish as storage time increased. When round scad muscle protein-based films were used to cover dried fish powder, the samples covered with the film containing 25% palm oil and 40% chitosan showed lower thiobarbituric acid reactive substances (TBARS) and yellowness than other samples during the extended storage up to 21 days (p < 0.05). No differences in moisture content of all samples covered with different films were noticeable (p > 0.05), except those covered with HDPE, which had the lowest moisture content. Thus, round scad protein-based film incorporated with palm oil and chitosan could be a promising packaging material to prevent lipid oxidation in oil enriched foods.     

Quercetin dietary supplementation of fattening lambs at 0.2% rate reduces discolouration and microbial growth in meat during refrigerated storage

Thirty-two Merino lambs fed barley straw and a concentrate formulated either with palm oil (CTRL group) plus quercetin (QCT group) or flaxseed (FS group) plus quercetin (FS-QCT group) were used to assess the effects of this flavonoid on meat quality attributes. The animals were slaughtered after being fed for at least 5 weeks with the experimental diets. Chemical composition of longissimus thoracis (LT) muscle was not different among treatments. The longissimus lumborum (LL) samples of QCT and FS-QCT groups revealed lower discolouration (hue angle) when compared to the CTRL and FS lambs (P < 0.05), whereas extract release volume (ERV) and microbiological data jointly suggest that flaxseed and quercetin may reduce the growth of microbial populations responsible for meat spoilage in quadriceps femoris (QF).     

Performance,carcass traits,muscle fatty acid composition and meat sensory properties of male Mahabadi goat kids fed palm oil,soybean oil or fish oil

This study examined the effect of palm, soybean or fish oils on the performance, muscle fatty acid composition and meat quality of goat kids. Twenty-four male Mahabadi kids (BW = 19.4 ± 1.2 kg) were divided into three groups according to liveweight and randomly allocated to one of three diets. Animals were fed ad libitum for 84 days. Different dietary fat sources had no effect on performance and/or carcass quality attributes. The soybean oil diet decreased 16:0 and 18:0 concentrations and increased 18:2 and 18:3 and the ratio of PUFA/SFA in the muscle compared with other treatments. Fish oil feeding increased 20:5 n-3 and 22:6 n-3 concentrations and decreased the ratio of n-6/n-3 in the muscle. The results demonstrate that the use of fish oil is a nutritional strategy to improve the health claimable long-chain omega-3 fatty acid content and n-6/n-3 ratio in goat meat without changing the sensory properties or colour of meat.     

Diet supplementation with fish oil and sunflower oil to increase conjugated linoleic acid levels in milk fat of partially grazing dairy cows

The objective of this study was to determine the long-term effect on milk conjugated linoleic acid (cis-9, trans-11 CLA) of adding fish oil (FO) and sunflower oil (SFO) to the diets of partially grazing dairy cows. Fourteen Holstein cows were divided into 2 groups (7 cows/treatment) and fed either a control or oil-supplemented diet for 8 wk while partially grazing pasture. Cows in group 1 were fed a grain mix diet (8.0 kg/d, DM basis) containing 400 g of saturated animal fat (control). Cows in the second group were fed the same grain mix diet except the saturated animal fat was replaced with 100 g of FO and 300 g of SFO. Cows were milked twice a day and milk samples were collected weekly throughout the trial. Both groups grazed together on alfalfa-based pasture ad libitum and were fed their treatment diets after the morning and afternoon milking. Milk production (30.0 and 31.2 kg/d), milk fat percentages (3.64 and 3.50), milk fat yield (1.08 and 1.09 kg/d), milk protein percentages (2.97 and 2.88), and milk protein yield (0.99 and 0.91 kg/d) for diets 1 and 2, respectively, were not affected by the treatment diets. The concentrations of cis-9, trans-11 CLA (1.64 vs. 0.84 g/100 g of fatty acids) and vaccenic acid (5.11 vs. 2.20 g/100 g of fatty acids) in milk fat were higher for cows fed the oil-supplemented diet over the 8 wk of oil supplementation. The concentration of cis-9, trans-11 CLA in milk fat reached a maximum (1.0 and 1.64 g/100 g of fatty acids for diets 1 and 2, respectively) in wk 1 for both diets and remained relatively constant thereafter. The concentration of vaccenic acid in milk fat followed the same temporal pattern as cis-9, trans-11 CLA. In conclusion, supplementing the diet of partially grazing cows with FO and SFO increased the milk cis-9, trans-11 CLA content, and that increase remained relatively constant after 1 wk of oil supplementation.     

Fish oil in feeds for entire male and female pigs: Changes in muscle fatty acid composition and stability of sensory quality

A total of 72 crossbred [(Norwegian Landrace × Yorkshire) × Duroc] male and female growing-finishing pigs were restrictedly fed diets containing fish oil to study the fatty acid composition of Musculus longissimusdorsi and sensory quality of belly and neck. Six diets were used: two low-fat diets with or without 0.5% fish oil added, and four medium-fat diets with palm kernel oil to fish oil in ratios given as % inclusion: 4.1:0.0, 3.9:0.3, 3.6:0.5 and 3.4:0.7. Feeding fish oil gave a dose-dependent response between fatty acids in the diets and in the M.longissimusdorsi and increased the level of very long chain n−3 fatty acids, especially the C22:5n−3 (DPA). A more efficient n−3 fatty acids deposition was obtained when given as a medium-fat diet rather than the low-fat diet. Female pigs had a significant higher percentage of monounsaturated fatty acids and C18:1 than males suggesting a gender related difference in the delta-9-desaturase activity. No significant differences were found in sensory attributes for short-term stored neck and belly. For pigs fed the highest level of fish oil (0.7%) long-term stored (12 months at −80 °C, 6 months at −20 °C) belly showed a slight increase in fish oil flavour. After warmed-over treatment, fish oil odour and flavour as well as rancid flavour were increased in this group. The results suggest levels of dietary fish oil up to 0.5% produce a healthier meat fatty acid composition, without negative effects on sensory attributes, even in long-termed stored belly.     

Meat goat kids finished on alfalfa,red clover or orchardgrass pastures: Carcass merit and meat quality

This experiment was conducted in 2005–2007 to evaluate carcass and chevon (goat meat) quality parameters when meat-goat kids (n = 72) were finished on alfalfa (Medicago sativa L; ALF); red clover (Trifolium pratense L.; RCG); or orchardgrass (Dactylis glomerata L.; OGR) pastures. Carcass conformation score was greater (P = 0.08) when meat-goat kids were finished on ALF compared to OGR with RCG intermediate. Chevon meat samples from goats finished on the three pasture treatments did not differ in ash, intramuscular fat, or crude protein content or in concentrations of omega6 and omega3 fatty acids, or the omega6 to omega3 ratio. Goats finished on OGR had higher (P < 0.001) 18:1 trans-11 fatty acids (FA) compared to ALF or RCG. Overall, meat-goat kids finished on ALF, RCG, or ORG produced desirable carcass weights for most niche markets in the USA. Chevon is a low-fat meat option with high desirable fatty acids for human diets.     

Effects of dietary broccoli fibre and corn oil on serum lipids, faecal bile acid excretion and hepatic gene expression in rats

To determine the effects of broccoli fibre and corn oil on lipid metabolism, male Sprague-Dawley rats were fed diets containing high (30%) or low (5%) corn oil, in combination with either 7.5% broccoli fibre or cellulose, for 4 months. High corn oil groups had significantly lower serum cholesterol and triglycerides than had low corn oil groups (p < 0.001). Broccoli fibre also lowered serum cholesterol and triglyceride levels compared to cellulose fibre. Faecal bile acid concentrations were higher in high corn oil-fed rats than in low corn oil-fed rats, with broccoli fibre inclusion in high corn oil diets resulting in higher faecal bile acid concentrations. Regardless of corn oil level, broccoli fibre supplementation in the diet resulted in an increase (p = 0.018) in hepatic cytochrome P450, family 7A1 (CYP7A1) expression. High corn oil feeding resulted in reduced expression of fatty acid synthase (FAS) and increased expression of carnitine palmitoyl transferase 1a (CPT1a) and 3-hydroxy-3-methyl-coenzyme A reductase (HMGCR) (p < 0.05). Our findings suggest that high dietary corn oil and broccoli fibre have beneficial effects on lipid metabolism. Corn oil lipid-lowering effects may be due to alteration of hepatic expression of genes involved in lipid synthesis and increased rate of cholesterol catabolism to bile acids. Broccoli fibre may also act via its physical properties to reduce enterohepatic bile acid recycling and intestinal lipid absorption, and increase luminal binding of bile acids, resulting in increased faecal bile acid excretion.     

Growth and meat quality of kids of indigenous Greek goats (Capra prisca) as influenced by dietary protein and gastrointestinal nematode challenge

The effect of dietary protein and gastrointestinal nematode (GIN) parasitism on growth and meat quality of growing kids was assessed using sixty (60) kids in three groups (n = 20); A: control, B: regularly treated with ALBENDAZOLE^® and C: supplemented with dietary protein. The kids grazed in a pasture contaminated with L3 larvae of GIN. Growth and condition score were assessed at 21-day intervals. After 86 days all kids were slaughtered. Carcasses were assessed for conformation, fatness, ultimate pH and other meat quality characteristics. Parasitic challenge was assessed by means of faecal egg counts (FEC), pasture larvae and adult nematodes in the GI tract of kids at slaughter. Groups C and B had higher growth rates and body condition score and produced significantly heavier (P < 0.05) carcasses with better (P < 0.01) conformation and fatness when compared to those of group A. Total unsaturated and monounsaturated fatty acids were higher (P < 0.05) in fat tissue of groups B and C. Group A had the highest FEC and group C had the lowest (P < 0.05) FEC. The parasitic challenge of L3 on pasture reached its highest point at 42 days and there were significant (P < 0.01) differences between the numbers of Teladorsagia spp., Trichostrongylus spp., Haemonchus contortus, Oesophagostomum spp. and Chabertia spp. found in the GI tract of kids between the three groups; group A had the highest numbers. Overall, the results showed that the increased protein content in the diet of growing kids grazing on a pasture contaminated with L3 nematode larvae resulted in the production of acceptable carcasses.