Muscle Fatty Acid Content Research Articles

Effects of Key Rumen Bacteria and Microbial Metabolites on Fatty Acid Deposition in Goat Muscle

In this study, the fatty acid composition in the muscles of Hechuan white goats was correlated with the metabolome and metagenome of their rumen contents, and potential effects of the metabolites and microorganisms in the rumen on host muscle fatty acid deposition were analyzed. The results of the correlation analysis between the rumen content’s metabolome and muscle fatty acid content showed that vitamin-B-related metabolites were significantly correlated with fatty acid content (p < 0.05). Most of these metabolites were positively correlated with stearic acid and negatively correlated with palmitic acid. In accordance with the level of fatty acid content, significant differences were found in the microbial species and abundance among groups at the species level. An abundance of Bacteroides, Ruminococcaceae P7, Eubacterium ruminant, and Prevotella in the rumen was significantly correlated with fatty acid content. These results provide data support for the development of targeted feeding management strategies to improve the quality of goat meat.

Dietary supplementation with succinic acid improves growth performance and flesh quality of adult Nile tilapia (Oreochromis niloticus) fed a high-carbohydrate diet

To evaluate the effects of dietary supplementation with succinic acid on growth performance, flesh quality, glucose, and lipid metabolism of Nile tilapia (Oreochromis niloticus) fed a high-carbohydrate diet (HCD), five iso-nitrogenous and iso-lipidic diets were prepared as follows: HCD (control group) consisting of 55% corn starch and HCD supplemented with 0.5%, 1.0%, 2.0%, and 4.0% succinic acid, respectively. Tilapia with an initial body weight of 204.90 ± 1.23 g randomly assigned to 15 tanks with 3 replicates per group and 10 fish per tank fed for 8 weeks. Increasing dietary succinic acid supplementation resulted in significant second-order polynomial relationship in the weight gain rate (WGR), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency rate (PER), viscerosomatic index, condition factor, and contents of muscular crude lipid and glycogen (P < 0.05). The hepatosomatic index, mesenteric fat index, liver glycogen content and crude lipid contents of the whole-body and liver demonstrated significantly linear and second-order polynomial relationship (P < 0.05). Quadratic curve model analysis based on WGR, SGR, PER, and FCR demonstrated that optimal supplementation with succinic acid in the HCD of Nile tilapia ranged from 1.83% to 2.43%. Fish fed with 1.0% succinic acid had higher muscular hardness, increased the contents of alkali-soluble hydroxyproline in collagen, docosahexaenoic acid (DHA) and n-3 polyunsaturated fatty acid (n-3PUFA) in muscle, and lower total fatty acid content in muscle (P < 0.05) compared with the control group. Compared to the control group, dietary supplementation with 1.0% succinic acid significantly increased the contents of total bounding amino acid (arginine, histidine, isoleucine, lysine, methionine, alanine, proline), total flavor amino acid (free aspartic acid), the catalase (CAT) activity and total antioxidant capacity, and the mRNA relative expression levels of CAT, superoxide dismutase (SOD), and nuclearfactor erythroidderived 2-like 2 (Nrf2) in muscle (P < 0.05). Furthermore, succinic acid supplementation significantly up-regulated mRNA relative expression levels of glycolysis genes (hexokinase 2 [HK2], phosphofructokinase, muscle-A [PFKMA], and phosphofructokinase, muscle-B [PFKMB]), a key glycogen synthesis gene (glycogen synthase [GYS]), and lipid catabolism genes (carnitine palmitoyltransferase-1B [CPT1B], hormone sensitive lipase [HSL], and lipoprotein lipase [LPL]), while down-regulating the mRNA relative expression level of fatty acid synthase (FASN) in muscle (P < 0.05). In conclusion, dietary supplementation with 1.83% to 2.43% succinic acid improved muscle quality by increasing muscle antioxidant capacity and hardness, changing muscle amino acid and fatty acid composition, and regulating muscle glucose and lipid metabolism.

Growth performance and fatty acids profile of common carp fed with raw black soldier fly larvae and honey bee drone brood

Abstract The present study aimed to compare the growth performance and liver and muscle fatty acid (FA) profile of juvenile common carp fed with raw black soldier fly (BSFL; Hermetia illucens) and honey bee drone brood (BDB; Apis mellifera), a novel insect in aquaculture, with a commercial carp diet (CCF). After 6 weeks, the weight gain and specific growth rate were significantly higher in fish fed with CCF, followed by the BDB-fed and BSFL-fed fish, with significant differences among groups. The essential FA contents in feeds were disproportionally mirrored in fish livers and muscles, suggesting feed-dependant biosynthesis ability in common carp. In conclusion, the results suggest that dietary FAs affect the muscle FA composition of common carp. Yet, the composition of dietary essential FAs content did not mirror the essential FA content in muscle, confirming the biosynthesis of essential FAs. The BDB appeared to be a viable alternative or supplement to CCF compliant with circular bioeconomy without compromising the FA profile of common carp muscles. Despite the low growth performance of fish fed with BSFL, this diet indicated good nutritional qualities regarding the FA profiles.

In Vitro Antioxidant Activities of Plant Polyphenol Extracts and Their Combined Effect with Flaxseed on Raw and Cooked Breast Muscle Fatty Acid Content, Lipid Health Indices and Oxidative Stability in Slow-Growing Sasso Chickens.

Adding flaxseed was found to decrease oxidative stability in feed and increase the antioxidant needs of chicken. This has also been associated with a decrease in the nutritional value and oxidative stability of meat if sufficient dietary antioxidants are not included. Furthermore, dietary flaxseed has been explored in fast-growing chickens as such studies are limited with slow-growing chickens. Thus, this study aimed to evaluate the effects of feeding plant polyphenol extracts as an antioxidant alongside flaxseed on fatty acid content, oxidative stability, and lipid health indices in breast muscle of slow-growing Sasso T451A dual-purpose chicken. A total of 126 chickens assigned to six groups (seven replicates of three) were fed on NC (control and no antioxidants), FS (75 g flaxseed and no antioxidants), VE8 (75 g flaxseed and 800 mg vitamin E), TS8 (75 g flaxseed and 800 mg Thymus schimperi), DA8 (75 g flaxseed and 800 mg Dodonaea angustifolia) and CD8 (75 g flaxseed and 800 mg Curcuma domestica) extract per kg diet. Feeding on CD8 and VE8 in raw and TS8, CD8 and VE8 diets in cooked breast muscle increased (p < 0.05) the C22:6n − 3 (DHA) and C20:5n − 3 (EPA) contents compared to the FS diet. Feeding FS increased (p < 0.05) the malondialdehyde (MDA) content in breast muscle, whereas TS8 in cooked and raw and CD8 and DA8 diets in raw breast muscle decreased it (p < 0.05). No added benefit was observed in feeding VE8 over plant extracts in terms of improving fatty acid composition and lipid health indices and reducing lipid oxidation in breast meat.

The antioxidant ability, histology, proximate, amino acid and fatty acid compositions, and transcriptome analysis of muscle in juvenile hybrid grouper (♀ Epinephelus fuscoguttatus × ♂ Epinephelus lanceolatus) fed with oxidized fish oil

The hybrid grouper (♀ Epinephelus fuscoguttatus × ♂ Epinephelus lanceolatus), as an important economic fish, has attracted much attention for its meat quality, and its meat quality is closely related to the composition of diet. In this study, a rearing experiment was conducted for 65 days with diets containing 0, 3, 6, and 9% oxidized fish oil (referred to as R, L, M and H group respectively) to investigate the effects of oxidized fish oil on the antioxidant ability, histology, proximate, amino acid and fatty acid compositions, and transcriptome analysis of muscle in juvenile hybrid grouper. As the proportion of oxidized fish oil increased in diet, the vitamin E concentration and antioxidant enzymes activities decreased significantly in muscle, but malondialdehyde (MDA) and total antioxidant capacity (T-AOC) showed the opposite trend, and the destruction of muscle fiber by oxidative stress was increasing. At the same time, the proximate composition, amino acid and fatty acid content in muscle were affected by oxidative stress. A total of 43,469 unigenes were obtained in transcriptome with 76 differentially expressed genes. There were 3 significant pathways including vitamin B6 metabolism, biosynthesis of amino acids, and p53 signaling pathway, and the significant pathways involved 5 different genes including phosphatase, phosphoglycerate mutase 2 (PGAM2), S-adenosylmethionine synthase isoform type-2 (SAM2), protein shisa-5-like (SHISA5), and growth arrest and DNA damage-inducible protein GADD45 beta-like (GADD45β). In conclusion, the dietary oxidized fish oil caused oxidative stress of muscle, and oxidative stress destroyed muscle fiber structure. Meanwhile, the oxidative stress changed muscle nutrition. In addition, the oxidative stress changed the muscle transcriptome profile.

Effects of Replacing Yellow Corn with Olive Cake Meal on Growth Performance, Plasma Lipid Profile, and Muscle Fatty Acid Content in Broilers.

Simple SummaryYellow corn is a grain frequently utilized in broiler diets. Moreover, the new era of the corn-ethanol industry for biofuel production has increased the divergence of energy applications of corn. These uses have considerably increased corn prices over the past few years. Using byproducts may be one of solutions to this problem. Olive cake meal (OCM) is a byproduct obtained from olive oil factories after olive oil is extracted. It has a high nutritional value, especially in regard to metabolizable energy. OCM has been used successfully in livestock and poultry feeding as an alternative to energy sources such as corn, without any adverse effects on performance. Hence, the current study investigated the effects of replacing yellow corn with OCM on the growth, nutrient utilization, selected blood parameters, and muscle fatty acid profile of broilers. Four hundred and eighty one-day-old male broiler chickens (Ross 308) were divided into four experimental groups (a control group, and groups with 5%, 10%, and 20% of corn replaced with OCM). The results revealed that replacing 10% of corn with OCM in the diet improved growth performance and reduced abdominal fat and liver malondialdehyde (MDA) and increased high density lipoprotein (HDL).The current study focused exclusively on evaluating the effects of replacing corn with olive cake meal (OCM) in the diet of broilers on their growth performance, abdominal fat, selected plasma parameters, and muscle fatty acid (FA) content. A total of 480 one-day-old male broiler chickens (Ross 308) were divided into four treatment groups with 12 replicates/treatment. The control group was fed the base diet, whereas the second to fourth groups were fed diets of corn with 5%, 10%, and 20% contents of OCM, respectively. Broilers fed with the 5% and 10% OCM diets showed better body weight (p = 0.04) and feed conversion ratio than the 20% OCM group (p < 0.048). Both nitrogen retention and ether extract digestibility were not improved by replaced corn with OCM. Replacing corn with OCM led to a decreased abdominal fat percentage (p = 0.023) compared with the control group. Birds in the OCM groups showed the lowest total cholesterol values (p = 0.038). The breast muscle (musculus pectoralis superficialis) content of oleic and linoleic, linolenic, and arachidonic acids was significantly high in birds fed with OCM diets. However, their palmitic acid level was significantly decreased. Vitamin E was increased by increasing the OCM level. Thus, we concluded that replacing corn with OCM, especially at a 10% level, is more effective than other replacement levels in improving growth performance, plasma lipid profile, and muscle FA content, as well as in causing a reduction in abdominal fat in broilers.

Effects of dietary arachidonic acid and docosahexanoic acid at different carbohydrates levels on gilthead sea bream growth performance and intermediary metabolism

A growth trial was performed to assess the interactive effects of high dietary levels of arachidonic acid (ARA) or docosahexaenoic acid (DHA), and carbohydrates on growth performance, feed utilization, proximate composition, plasma metabolites, and intermediary metabolism. Four isoproteic (47% crude protein) and isolipidic (18% crude lipids) diets were formulated for gilthead sea bream juveniles (47.5 g of initial mean body weight) to include low or high gelatinized starch (5 and 20% starch; LS and HS diets, respectively) and different dietary ARA/DHA content (2.3/0.3 and 0/2.6; ARA and DHA diets, respectively). Dietary ARA/DHA content did not affect growth performance or feed utilization. However, dietary starch inclusion increased feed efficiency, protein efficiency ratio, and energy retention (% intake). Dietary ARA/DHA profile did not affect the whole-body composition, but dietary starch increased whole-body dry matter, lipid, and gross energy content and decreased protein content. Low dietary ARA/DHA ratio increased plasma total protein and total lipids, triglycerides, and very-low-density lipoprotein cholesterol (VLDL) and decreased high-density lipoprotein cholesterol (HDL) and low-density lipoprotein cholesterol (LDL), independently of the dietary starch level. On the other hand, in LS diets, total cholesterol levels were lower in fish fed the diet rich in DHA than those fed with ARA. HS diets increased glucose, total protein and lipids, triglycerides, and VLDL plasmatic values, and decreased HDL. HS diets increased the carbohydrates intermediary metabolism and lipogenic enzymes. ARA and HS increased fatty acid desaturase 2 (FADS2) and decreased elongation of very long-chain fatty acid 5 protein (ELOVL5) in the liver, and only HS decreased ELOVL5 in the intestine. The muscle fatty acid content followed the dietary fatty acid profile, but ARA, EPA, and DHA content were increased in LS diets. In conclusion, few interactions between ARA or DHA and dietary digestible carbohydrates were found. The results indicate that at least in the presence of high ARA levels the n-3 LC-PUFA requirements were fulfilled with 0.5% EPA + DHA and gilthead sea bream tolerates well dietary inclusion of 20% starch.

Effect of Dietary Olive Cake Supplementation on Performance, Carcass Characteristics, and Meat Quality of Beef Cattle.

Dietary partially destoned olive cake supplementation on performance, carcass traits and meat quality of intensively finished bulls was evaluated. Forty-five Limousin bulls, divided into three homogenous groups, received a diet with no supplementation (Control-CTR), 7.5% (Low Olive Cake-LOC), and 15.0% of olive cake supplementation (High Olive Cake-HOC). The trial was realized for 150 days; all bulls were individually weighed at the beginning, middle, and end of the trial, to calculate the individual average daily gain (ADG). At slaughtering, on each carcass, hot weight was recorded and, after 7 days, the pH and temperature were measured. On Longissimus lumborum muscle, color, cooking loss, and shear force of the cooked sample were determined. The chemical composition and the fatty acid content of muscle were determined. Olive cake inclusions (7.5% and 15.0%) increased (p < 0.05) the body weight, ADG, slaughter traits and intramuscular fat content and influenced (p < 0.05) the quality indices. The 15.0% of the inclusion reduced (p < 0.05) the cooking loss and shear force, and increased the unsaturated fatty acid content. The olive cake can be considered as a functional component in beef production and, in substitution to a quote of cereals into the diet of bulls, could be an opportunity to improve agriculture sustainability.

Olive Cake Meal and Bacillus licheniformis Impacted the Growth Performance, Muscle Fatty Acid Content, and Health Status of Broiler Chickens.

Simple SummaryThe extraction of oils from olives usually results in large quantities of olive cake meal (OCM), which has a high nutritional value. The OCM is used successfully in livestock and poultry feeding, but due to the high fiber content, alternative methods of treating OCM must be considered. To increase the efficiency of OCM in broiler chickens’ diet, it can be mixed with suitable microorganisms with beneficial effects. Hence, the current study investigated the influence of OCM and Bacillus licheniformis (BL) on the growth, nutrient utilization, blood chemistry, and muscle fatty acid profile of broilers. Birds were divided into six experimental groups (control, OCM (2%), OCM (4%), BL, OCM (2%)/BL, and OCM (4%)/BL groups). The results revealed that the inclusion of BL with OCM diets improved the fat utilization and, accordingly, increased the growth, nutrient utilization, and antioxidative response in broilers.Olive cake meal (OCM) is characterized by its high nutritional value and is used as an alternative source of protein and fats in poultry diets. However, due to the high percentage of fiber in OCM, beneficial bacteria cells are used to improve the digestion rates. Therefore, the influence of OCM and Bacillus licheniformis (BL) on the growth, nutrient utilization, blood chemistry, and muscle fatty acid profile of broilers was exclusively examined in this study. Three hundred and sixty birds were randomly divided into six experimental groups (6 replicates/10 birds each): Control, OCM (2%), OCM (4%), BL, OCM (2%)/BL, and OCM (4%)/BL groups. Although feed intake was not meaningfully influenced by dietary treatments, weight gain was enhanced and feed conversion ratio was reduced (p < 0.05). The abdominal fat was lowered in broilers fed OCM (2%), OCM (4%), OCM (2%)/BL, and OCM (4%)/BL diets without a difference to those fed BL only (p < 0.05). Interestingly, blood total protein, albumin, Newcastle disease (ND) titer, and high-density lipoprotein (HDL) cholesterol were significantly increased, while total cholesterol was decreased by the mixture of OCM and BL (p < 0.05). Muscle oleic and linoleic acids, as well as vitamin E, increased significantly in broilers fed both OCM (4%) and BL, while linolenic acid increased in all groups except those fed BL and control diets (p < 0.05). Liver malondialdehyde (MDA) was decreased by feeding BL or both OCM at 2% or 4% and BL (p < 0.05). In conclusion, the inclusion of BL to OCM diets resulted in improved fat utilization and, accordingly, enhanced growth, nutrient utilization, and antioxidative response in broilers. Based on the obtained results, it is recommended to use BL to improve the nutritional value of OCM and to increase the feed utilization of OCM by broilers.

Fatty Acid Content, Flavor Compounds, and Sensory Quality of Pork Loin as Affected by Dietary Supplementation with l-arginine and Glutamic Acid.

To investigate the effect of functional amino acid on meat flavor and eating quality, 60 growing-finishing pigs (Duroc × Large White × Landrace) were dietarily supplemented with or without 1.0% l-arginine, glutamic acid, or l-arginine plus glutamic acid for 2 months. After animals were slaughtered, the muscle fatty acid profile, flavor compounds, and meat sensory quality were comparatively investigated. The results showed that dietary supplementation with arginine, glutamic acid, or arginine plus glutamic acid had little effect on free amino acids, no effect on 5'-nucleotides and meat sensory taste traits, but supplementation with arginine plus glutamic acid significantly increased (P<0.05) fat accumulation and fatty acid content in muscle, increased (P<0.05) the formation of multiple fatty acid oxidation-derived volatile compounds, and improved the tenderness, juiciness, and overall eating quality of meat. This study revealed that dietary supplementation with 1.0% l-arginine and glutamic acid could be used to improve meat eating quality in pork production.

The Utilization of Algae with the Aim to Increase the Fatty Acid Content in Muscle of Common Carp (Cyprinus carpio L.)

The aim of this study was to evaluate the efficiency of feeds with the addition of various algae and cyanobacteria. Common carp (average body mass of 19.6 ± 3.49 g) were randomly divided into 4 groups and fed a commercial feed (control group), the same commercial feed with the addition of 10 % of dry green algae of the genus Chlorella (chlorella group), dry biomass of algae from waste water treatment (algae group), and lyophilized toxic cyanobacterial biomass of the genus Microcystis (microcystis group). After 29 days of the experiment, standard indices for the assessment of feed utilization, external characteristics, fish condition, chemical composition of muscles and composition of fatty acids were measured. The feed variants with the addition of green algae (chlorella and algae groups) appeared to be nutritionally more favorable in our experiment. A higher content of PUFAs and total amount of fats (expressed in units of weight) were found in the groups of fish fed the green algae and algae from waste water treatment supplemented feed.

Enhanced Omega-3 Polyunsaturated Fatty Acid Contents in Muscle and Edible Organs of Australian Prime Lambs Grazing Lucerne and Cocksfoot Pastures.

The enhancement of health-beneficial omega-3 long–chain (≥C20) polyunsaturated fatty acid (n-3 LC-PUFA) contents in the muscle, liver, heart, and kidney of Australian prime lambs through pasture grazing and supplementation with oil infused pellets was investigated. Forty-eight first-cross prime lambs were randomly assigned into a split-plot design with pasture type as the main plot effect and pellet supplementation as a sub-plot effect in a feeding trial that lasted for nine weeks. The n-3 LC-PUFA content in Longissimus dorsi muscle of all lambs was well above the 30 mg threshold for “omega-3 source” nutrition claim under the Australian Food Standards and Guidelines. Pasture type impacted the fatty acid contents in muscle, heart, and kidney of prime lambs. Lambs grazing cocksfoot grass only had high 18:3n-3 (ALA) and n-3 LC-PUFA contents (67.1 mg/100 g and 55.2 mg/100 g, respectively) in the Longissimus dorsi muscle, which was not significantly different (p > 0.8990) from the contents of lambs grazing only lucerne. Supplementation of pellets with or without oil infusion to grazing lambs generally decreased the ALA and n-3 LC-PUFA contents and increased the n-6/n-3 ratio in the Longissimus dorsi muscle. The fatty acid content in the internal organs of grazing lambs was also affected by pellet supplementation. The liver and kidney of grazing lambs were both “good sources” (60 mg/100 g) of omega-3. The cocksfoot grass showed considerable potential for producing healthy, premium quality meat with high contents of n-3 and n-3 LC-PUFA, which may consequently enhance the omega-3 intake of Australian lamb consumers.

Comparative transcriptomics identifies genes differentially expressed in the intestine of a new fast-growing strain of common carp with higher unsaturated fatty acid content in muscle.

We have created a new, fast-growing strain of common carp with higher unsaturated fatty acid content in muscle. To better understand the impacts of gene regulation in intestinal tissue on growth and unsaturated fatty acid content, we conducted a comparative RNA-Seq transcriptome analysis between intestine samples of Selected and Control groups (and corroborated selected results by PCR). After eight weeks of cage culture, weight gain of the Selected group was 20.84% higher. In muscles of the control group, monounsaturated fatty acids (FAs) were more abundant, whereas polyunsaturated FAs were more abundant in muscles of the Selected group. In total, we found 106 differentially expressed genes (DEGs) between the two groups. Only the endocytosis pathway was significantly enriched in DEGs, with two upregulated genes: il2rb and ehd1. The latter is involved in the growth hormone/insulin-like growth factor (Gh/Igf) axis, which plays a key role in the regulation of growth in animals. tll2, which is known to be associated with intestinal regeneration, was extremely highly upregulated in both transcriptomic (infinite) and qPCR (610.70) analyses. Two of the upregulated genes are associated with the fatty acid metabolism, several genes are likely to be indicators of heightened transcription levels, several are associated with metabolic and developmental roles, several with neuronal functions (including two with vision), several with the immune system, and two downregulated genes with the development of vasculature. The higher growth rate of the Selected group is likely to be at least partially attributed to increased endocytosis efficiency and genetically-driven behavioural differences (higher aggression levels). There are some indications that this new strain might have slightly impaired immune responses, and a higher propensity for inherited diseases leading to sight impairment, as well for neurodegenerative diseases in general, but these indications still need to be confirmed.

Muscle Fatty Acid Content in Selected Freshwater Fish from Bukit Merah Reservoir, Perak, Malaysia.

One of the oldest reservoirs in Peninsular Malaysia, Bukit Merah Reservoir, is a place in which locals participate in fishing activities. Inland fisheries are important to individuals, society and the environment; whereby they generate a source of income and food security. It is essential to gauge the nutrition value of fish caught in this location as food source, especially in terms of fatty acid composition, to better demonstrate its potential towards the betterment of human health and general well-being. From an initial list of 47 fish species available in Bukit Merah Reservoir, a total of seven edible freshwater fish species were identified, namely tinfoil barb (Barbonymus schwanenfeldii), Javanese barb (Barbonymus gonionotus), hampala barb (Hampala macrolepidota), beardless barb (Cyclocheilichthys apogon), glassfish (Oxygaster anomalura), striped snakehead (Channa striata) and horseface loach (Acantopsis dialuzona), and muscle fatty acid content was analysed to determine their nutritional value. Muscle of cyprinid fish contained substantial amount of omega-3 long-chain polyunsaturated fatty acids (LC-PUFA) compared to fish from Channidae and Cobitidae families. Javanese and tinfoil barbs muscle recorded the highest levels of combined eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) indicating the highest nutritional value comparatively. Unexpectedly, the striped snakehead, a predatory carnivore, contained lower levels of LC-PUFA compared to detrivorous/herbivorous fishes. This further justifies that the omega-3 polyunsaturated fatty acids (PUFA) content in fish muscle varies according to their feeding habits. Even though it has been recommended that marine fish be consumed to improve health to a certain extent, there still are benefits of consuming freshwater fish, as there are several species which contain considerable amounts of beneficial omega-3 PUFA.

Planktivorous vendace (Coregonus albula) utilise algae‐derived fatty acids for biomass increase and lipid deposition

AbstractSpatial and seasonal variation in the abundance and composition of phytoplankton and other basal resources (bacteria, terrestrial detritus) influence the availability of essential polyunsaturated fatty acids (PUFA) for upper trophic levels in lake food webs. We studied accumulation, composition and content of fatty acids in planktivorous vendace (Coregonus albula) muscle tissue during the summer feeding period (May to late September) in six boreal lakes. Vendace muscle fatty acid content increased from ~17.7 mg/g DW to ~28.1 mg/g DW from spring to summer, corresponding to a ~59% increase in total fatty acids. PUFA accounted for 45%–65% of all fatty acids, and the most abundant fatty acid was docosahexaenoic acid (DHA, 22:6n‐3). The DHA content remained relatively constant throughout the sampling period (~7–8 mg/g DW), but the proportion of DHA decreased from ~40% in spring to ~30% in summer and autumn. The decrease in DHA proportion was due to accumulation of other fatty acids, primarily C18 PUFA (predominantly synthetised by algae) and monounsaturated fatty acids. A similar fatty acid accumulation pattern was observed in lipid storing copepods, an important prey for planktivorous vendace. The abundance of bacterial and terrestrial biomarker fatty acids in vendace muscle and prey items was low (&lt;5% and &lt;0.1% respectively). The increase in weight and the deposition of internal energy stores in vendace were achieved predominantly by algae‐based food chain. This has ecological implications, as vendace requires sufficient lipid stores for reproduction in autumn and survival over winter.

Effect of whole flax seed and carbohydrase enzymes on gastrointestinal morphology, muscle fatty acids, and production performance in broiler chickens

Flax seed is a rich source of α-linolenic acid (18:3 n-3). Feeding broiler birds flax seed can increase n-3 fatty acids in meat tissues. However, non-starch polysaccharides in flax seed decrease nutrient digestibility and can have a negative impact on bird performance and muscle fatty acid content. Addition of carbohydrase enzymes to flax-based broiler diets can decrease the anti-nutritive effects of non-starch polysaccharides. An experiment was conducted to investigate on the effect of flax seed and carbohydrase enzyme foregut morphology, muscle tissue, fatty acids, and bird performance. A total of 112 five-day-old broiler chicks were assigned to one of four treatments: Flax10 (corn-soybean meal basal diet adjusted for 10% flax), Flax15 (basal diet adjusted for 15% flax), Flax10E (Flax10 + 0.05% enzyme), and Flax15E (Flax 15 + 0.05% enzyme). Addition of enzyme led to large increases in villi height and villi width in the jejunum of birds fed Flax10 and increases in crypt depth in the jejunum of birds fed Flax15 (P < 0.05). The ratio of villi height to crypt depth was larger in the duodenum and jejunum of birds fed Flax10E when compared to Flax10 (P < 0.05). Feeding the Flax15 diet led to a significant decrease in total lipids in breast muscle compared to Flax10 (P < 0.05). The effect of level of flax or enzyme supplementation was minimal on the fatty acids measured in breast muscle except for total n-6 fatty acids which was higher (P < 0.05) in Flax15 when compared to Flax10. In thigh muscle, stearic acid, arachidonic acid, and total n-6 fatty acids were higher in birds fed Flax15 vs. Flax10. Feeding Flax15 led to a reduction in dry matter of excreta when compared to Flax10 (P < 0.05). There were no differences in BW, average daily gain, or feed consumption during the starter or grower phase due to flax level or enzyme addition (P > 0.05).

Metabolism of Seriola lalandi during Starvation as Revealed by Fatty Acid Analysis and Compound-Specific Analysis of Stable Isotopes within Amino Acids.

Fish starvation is defined as food deprivation for a long period of time, such that physiological processes become confined to basal metabolism. Starvation provides insights in physiological processes without interference from unknown factors in digestion and nutrient absorption occurring in fed state. Juveniles of amberjack Seriola lalandi were isotopically equilibrated to a formulated diet for 60 days. One treatment consisted of fish that continued to be fed and fish in the other treatment were not fed for 35 days. The isotopic signatures prior to the beginning of and after the starvation period, for fish in the starvation and control treatments, were analysed for lipid content, fatty acid composition and isotopic analysis of bulk (EA-IRMS) and of amino acids (compound specific isotope analysis, CSIA). There were three replicates for the starvation group. Fatty acid content in muscle and liver tissue before and after starvation was determined to calculate percent change. Results showed that crude lipid was the most used source of energy in most cases; the PUFAs and LC-PUFAs were highly conserved. According to the protein signature in bulk (δ15N) and per amino acid (δ13C and δ15N), in muscle tissue, protein synthesis did not appear to occur substantially during starvation, whereas in liver, increases in δ13C and δ15N indicate that protein turnover occurred, probably for metabolic routing to energy-yielding processes. As a result, isotopic values of δ15N in muscle tissue do not change, whereas CSIA net change occurred in the liver tissue. During the study period of 35 days, muscle protein was largely conserved, being neither replenished from amino acid pools in the plasma and liver nor catabolized.

Dietary α-linolenic for juvenile Nile tilapia at cold suboptimal temperature

Nile tilapia farming occurs in tropical and subtropical climate areas worldwide but information about dietary fatty acid requirements of Nile tilapia, particularly when raised at suboptimal temperature, are scarce. Previous studies with Nile tilapia failed to detect growth differences at suboptimal growth temperatures. Therefore, the objective of this study was to estimate the dietary requirement of α-linolenic acid (α-LNA, 18:3n−3) of juvenile Nile tilapia, when raised at 22°C. Increasing levels of linseed oil were added to a mixture of vegetable oils, yielding the following concentrations of α-LNA: 0.03, 0.21, 0.37, 0.67 and 0.99% of diet dry weight. The basal diet was formulated with semipurified ingredients and contained 5% lipid. Juvenile tilapia (10.6±0.09g) were fed the experimental diets twice daily until satiation for 14weeks. The average water temperature throughout the experimental period was 22.12±0.17°C. The increase in dietary α-LNA significantly affected daily weight gain, specific growth rate, feed efficiency and daily feed intake. Total n−3 fatty acid content in muscle showed a significant linear response to dietary α-LNA. Likewise, an accumulation of muscle linoleic acid (18:2n−6) was directly related to the increase in dietary α-LNA, while n−6 long-chain polyunsaturated fatty acids (LC-PUFA) decreased. The dietary requirement of α-LNA estimated for juvenile Nile tilapia reared at 22°C was 0.70% diet for maximum weight gain and 0.68% for maximum feed efficiency. Statement relevanceNile tilapia, a tropical species, has been considered for aquaculture in subtropical regions, but its nutritional requirements under suboptimal temperatures are unknown. The present study shows that the α-linolenic requirement for this species under 22°C is slightly higher than in 28°C. Therefore, we suggest the increase in the α-linolenic levels in the diet for Nile tilapia during the cold seasons.

Organic practices and gender are effective strategies to provide healthy pork loin

This study evaluated the influence of husbandry (organic feed and management but not free-ranging vs. conventional) and sex (barrows vs. gilts) on pork meat quality. A total of 60 Longissimus thoracis pork muscle samples from different 3-way crossbred genotypes were chosen from 3 conventional and 2 organic pig farms. Technological meat quality was measured at 24 h post-mortem and muscle fatty acid content and composition was analysed by gas chromatography. The loin from organic pigs at 24 h of retail display had lower pH, but it had no detrimental effects on drip loss. All the International Commission on Illumination colour attributes except meat lightness differed between husbandry systems. Moisture and crude protein content were lower whereas intramuscular fat content was greater in organic than in conventional pork. Total saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA) and PUFA n-6 contents did not differ between husbandry systems, but total PUFA n-3 (mainly C18:3 n-3) were greater in organic than in conventional pork. Sex did not affect ultimate pH or meat colour attributes but barrows showed lower moisture and greater intramuscular fat than gilts. Total SFA and MUFA content were similar but all the PUFA (both n-6 and n-3) were lower in barrows than in gilts. These results suggest that some bioactive compounds from dietary origin, i.e., linolenic acid (C18:3 n-3) content from dietary vegetable oils (soybean or olive olein), might be used to highlight the nutritive value of (not free-ranging) organic pork meat. In addition, gilts were leaner than barrows and showed a more favourable PUFA/SFA ratio.

Animal performance, carcass characteristics and beef fatty acid profile of grazing steers supplemented with corn grain and increasing amounts of flaxseed at two animal weights during finishing

The objective of this study was to determine (1) the effects of increasing flaxseed addition to the corn grain supplemented at finishing to grazing steers on animal performance, carcass characteristics and longissimus muscle (LM) fatty acid profile, and (2) whether dietary treatments effects are affected by animal body weight (BW) at supplementation. Forty eight steers were assigned to eight treatment combinations defined by four dietary treatments (CNTRL, no supplement; FLAX-0, 0.7% BW of cracked corn grain; FLAX-1 and FLAX-2, FLAX-0 plus 0.125% and 0.250% BW of unprocessed flaxseed, respectively) and by two animal BW treatments generated by supplementing steer in early spring (EARLY) or late spring (LATE). Steers assigned to EARLY received their dietary treatment when reaching 366±27.3kg BW (August, 3rd) and those assigned to LATE when reaching 458±42.8kg (October, 10th). After 70d on trial, carcass data and LM samples (12th rib region) were collected for fatty acid (FA) analysis. Total DMI was greater in supplemented treatments (FLAX-0, FLAX-1 and FLAX-2) than in CNTRL, with no flaxseed level effect. Dietary treatment effects on performance and carcass characteristics were not affected by BW treatments. Increasing flaxseed supplementation linearly increased subcutaneous fat thickness; whereas increasing BW at initiation of supplementation decreased average daily again, but increase final BW, hot carcass weight, and LM total fatty acid content. Animal BW at initiation of supplementation affected dietary treatments effects on LM n-6/n-3 ratio; ratio was highest in FLAX-0 and lowest in CNTRL and FLAX-2 in both BW treatments; did not differ between BW treatments in CNTRL and in FLAX-2, but was greater in EARLY than in LATE in FLAX-0 and FLAX-1. Trans-vaccenic acid proportion was greater in CNTRL than in supplemented treatments, but was not affected by flaxseed level; similar trend was observed for CLA cis-9, trans-11 proportion. Linolenic acid proportion did not differ between CNTRL and supplemented treatments, but was linearly increased with flaxseed level. Fatty acids changes with increasing animal BW at supplementation were associated with the increased in total muscle fatty acid content; total and individual polyunsaturated fatty acids were lower in LATE than in EARLY, whereas trans-vaccenic acid and CLA cis-9, trans-11 were greater. Adding flaxseed to the corn grain supplemented increase subcutaneous fat thickness of grazing steers without negatively affecting fatty acid profile, except for a reduction in trans-vaccenic acid proportion. Therefore, adding flaxseed to the corn supplemented to grazing steers increases carcass fatness while reducing the negative effect of corn supplementation on LM n-6/n-3 ratio but not on trans-vaccenic acid. Increasing BW at supplementation reduces supplementation effects on LM n-6/n-3 ratio.