Fatty acid composition of several muscles and adipose tissues of pigs fed n-3 PUFA rich diets

Turning waste into treasure: A new direction for low-cost production of lipid chemicals from Thraustochytrids

Thraustochytrids are marine microorganisms known for their fast growth and ability to store lipids, making them useful for producing polyunsaturated fatty acids (PUFAs), biodiesel, squalene, and carotenoids. However, the high cost of production, mainly due to expensive fermentation components, limits their wider use. A significant challenge in this context is the need to balance production costs with the value of the end products. This review focuses on integrating the efficient utilization of waste with Thraustochytrids fermentation, including the economic substitution of carbon sources, nitrogen sources, and fermentation water. This approach aligns with the 3Rs principles (reduction, recycling, and reuse). Furthermore, it emphasizes the role of Thraustochytrids in converting waste into lipid chemicals and promoting sustainable circular production models. The aim of this review is to emphasize the value of Thraustochytrids in converting waste into treasure, providing precise cost reduction strategies for future commercial production.

Effects of Pig Dietary n-6/n-3 Polyunsaturated Fatty Acids Ratio and Gender on Carcass Traits, Fatty Acid Profiles, Nutritional Indices of Lipid Depots and Oxidative Stability of Meat in Medium-Heavy Pigs

The effects of different dietary n-6/n-3 polyunsaturated fatty acids (PUFA) ratios and gender on key carcass traits, as well as the nutritional and technological quality of lipids in medium-heavy pig tissues have been poorly studied. To investigate the subject, 24 Large White, barrows and gilts, evenly divided into two groups of 12, were fed from 80 kg of live-weight (LW) until slaughter at 150 kg LW, either a high (9.7:1) (HPR) or low (1.4:1) (LPR) dietary n-6/n-3 PUFA ratio. On individual samples of longissimus thoracis muscle (LTM), subcutaneous (SF) and perirenal (PF) adipose tissues (ATs), the fatty acid (FA) composition was determined by gas chromatography, and lipid nutritional indices (LNIs) were calculated. The oxidative stability of meat was evaluated by determining the malondialdehyde content on raw and cooked (24 h postmortem) and refrigerated (8 days postmortem) LTM samples. The carcass traits did not vary between genders and diets. The LPR group showed a higher n-3 PUFA level and a lower n-6/n-3 PUFA ratio in all the tissues examined and better LNI, especially in the ATs. Diet did not affect the oxidative stability of meat. Gender did not influence the n-6/n-3 PUFA ratio, while barrows showed improvements in some LNI in ATs. Reducing the n-6/n-3 ratio in the diet of growing-finishing medium-heavy pigs improved the FA profile in all tissues and most LNI in ATs without impairing the oxidative stability of meat.

Effect of the inclusion of extruded flaxseed in the diet of fattening pigs on lipid metabolism and tissue redox status

The aim of the study was to evaluate the effect of a diet containing extruded flaxseed (Linum usitatissimum L.) on the fatty acid composition of the loin, blood lipid parameters, and the redox status of tissues of finishing pigs. A total of 160 weaners (about 30-110 kg BW) were assigned to four experimental groups of 40 animals each (5 replicates with 8 individuals each). Group C (control) received a diet in which the fat source was soybean oil, while in groups 2FE, 4FE and 6FE soybean meal was replaced with extruded flaxseed in the amount of 2%, 4% or 6%, respectively. The diet containing extruded flaxseed reduced cholesterol levels in the blood plasma of pigs (grower 2FE and 6FE vs. C; finisher 2FE, 4FE and 6FE vs. C) and loin muscle (2FE, 4FE and 6FE vs. C). A decrease in the atherogenic LDL-C fraction and in the content of triacylglycerols was also noted in the blood plasma of grower and finisher pigs receiving flaxseed (2FE, 4FE and 6FE vs. C). The beneficial effects noted in the experimental pigs also included an increase in the overall content of n-3 PUFAs, especially ALA (18:3 n-3), and a reduction in the n-6/n-3 ratio. This was especially evident at 4% and 6% inclusion of flaxseed. The highest proportion of flax (6%) in the blend increased lipid peroxidation, as evidenced by the increase in the content of LOOH and MDA in the blood plasma of grower and finisher pigs. For this reason, a 4% share of flaxseed in the diet of fattening pigs seems to be optimal, while higher levels require an additional supply of exogenous antioxidants.

RNA-Seq Study on the Longissimus thoracis Muscle of Italian Large White Pigs Fed Extruded Linseed with or without Antioxidants and Polyphenols

The addition of n-3 polyunsaturated fatty acids (n-3 PUFAs) to the swine diet increases their content in muscle cells, and the additional supplementation of antioxidants promotes their oxidative stability. However, to date, the functionality of these components within muscle tissue is not well understood. Using a published RNA-seq dataset and a selective workflow, the study aimed to find the differences in gene expression and investigate how differentially expressed genes (DEGs) were implicated in the cellular composition and metabolism of muscle tissue of 48 Italian Large White pigs under different dietary conditions. A functional enrichment analysis of DEGs, using Cytoscape, revealed that the diet enriched with extruded linseed and supplemented with vitamin E and selenium promoted a more rapid and massive immune system response because the overall function of muscle tissue was improved, while those enriched with extruded linseed and supplemented with grape skin and oregano extracts promoted the presence and oxidative stability of n-3 PUFAs, increasing the anti-inflammatory potential of the muscular tissue.

Effects of multiple vitamin E levels and two fat sources in diets for swine fed to heavy slaughter weight of 150 kg: II. Tissue fatty acid profile, vitamin E concentrations, immune capacity, and antioxidant capacity of plasma and tissue

The study objective was to evaluate the effect of two fat sources and graded levels of vitamin E (VE) supplementation on tissue fatty acid profile, VE concentrations, immune capacity, and antioxidant capacity of plasma and tissues of pigs at heavy slaughter weight (150 kg). A total of 48 individually-fed pigs (24 barrows, 24 gilts; 28.44 ± 2.69 kg) were randomly assigned to eight dietary treatments in a 2 × 4 factorial arrangement. The two fat treatments were either 5% tallow (TW) or 5% distiller's corn-oil (DCO). The VE treatments included four levels of α-tocopheryl-acetate (11, 40, 100, and 200 ppm). Compared to pigs fed the DCO diet, pigs fed the TW diet had greater SFA (C14, C16, and C18; P < 0.05) and MUFAs (C14:1, C16:1, C18:1, and C20:1; P < 0.05), lower PUFA (C18:2n-6, C18:3n-3, C20:2, C20:3, and C20:4; P < 0.05) and iodine value in the backfat and belly fat. Increasing dietary VE supplementation level increased α- and total tocopherol concentrations in plasma (linear and quadratic, P < 0.05), liver, and loin muscle (linear, P < 0.06), superoxide dismutase activity (quadratic, P < 0.05), but decreased γ-tocopherol concentrations in liver (linear, P = 0.06), plasma, and loin muscle (quadratic, P < 0.07), and decreased liver glutathione disulfide (GSSG; linear, P = 0.07) and malondialdehyde (MDA) content (quadratic, P < 0.05). There was an interaction between fat sources and dietary VE supplementation level on the concentration of α-tocopherol in the loin muscle (P < 0.05) wherein a greater increase was observed in the TW treatment than the DCO treatment with the increasing dietary VE supplementation level. In conclusion, dietary FA composition in TW and DCO affected the composition of most FA in backfat, belly fat, and liver while increasing VE supplementation level did not significantly alter the FA profile in these tissues. Increasing dietary VE supplementation level increased tocopherol concentrations in plasma, liver and loin muscle, and improved antioxidant capacity while tocopherol concentrations in plasma, liver and loin muscle in the TW treatment increased more than they did in the DCO treatment.

Use of Microorganisms as Nutritional and Functional Feedstuffs for Nursery Pigs and Broilers

The objectives of this review paper are to introduce the structures and composition of various microorganisms, to show some applications of single cells as alternative protein supplements or energy feeds in swine and poultry diets, and to discuss the functional effects of microorganisms as feed additives on the growth performance and intestinal health of nursery pigs and broilers. Microorganisms, including bacteria, yeasts, and microalgae, have been commonly supplemented in animal diets because they are cost-effective, stable, and have quantitative production that provides nutritional and functional benefits to pigs and broilers. Microorganisms could be alternative antibiotics to enhance intestinal health due to bioactive components from cell wall components, which interact with receptors on epithelial and immune cells. In addition, bioactive components could be digested by intestinal microbiota to produce short-chain fatty acids and enhance energy utilization. Otherwise, microorganisms such as single-cell protein (SCP) and single-cell oils (SCOs) are sustainable and economic choices to replace conventional protein supplements and energy feeds. Supplementing microorganisms as feedstuffs and feed additives improved the average daily gain by 1.83%, the daily feed intake by 0.24%, and the feed efficiency by 1.46% in pigs and broilers. Based on the properties of each microorganism, traditional protein supplements, energy feeds, and functional feed additives could be replaced by microorganisms, which have shown benefits to animal's growth and health. Therefore, specific microorganisms could be promising alternatives as nutritional and functional feedstuffs in animal diets.

Are n-3 PUFAs from Microalgae Incorporated into Membrane and Storage Lipids in Pig Muscle Tissues?-A Lipidomic Approach

For the study of molecular mechanisms of to lipid transport and storage in relation to dietary effects, lipidomics has been rarely used in farm animal research. A feeding study with pigs (German Landrace sows) and supplementation of microalgae (Schizochytrium sp.) was conducted. The animals were allocated to the control group (n = 15) and the microalgae group (n = 16). Shotgun lipidomics was applied. This study enabled us to identify and quantify 336 lipid species from 15 different lipid classes in pig skeletal muscle tissues. The distribution of the lipid classes was significantly altered by microalgae supplementation, and ether lipids of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidic acid (PA) were significantly decreased. The total concentration of triacylglycerides (TAGs) was not affected. TAGs with high degree of unsaturation (TAG 56:7, TAG 56:6, TAG 54:6) were increased in the microalgae group, and major abundant species like TAG 52:2 and TAG 52:1 were not affected by the diet. Our results confirmed that dietary DHA and EPA are incorporated into storage and membrane lipids of pig muscles, which further led to systemic changes in the lipidome composition.

Health Benefits, Food Applications, and Sustainability of Microalgae-Derived N-3 PUFA

Today's consumers are increasingly aware of the beneficial effects of n-3 PUFA in preventing, delaying, and intervening various diseases, such as coronary artery disease, hypertension, diabetes, inflammatory and autoimmune disorders, neurodegenerative diseases, depression, and many other ailments. The role of n-3 PUFA on aging and cognitive function is also one of the hot topics in basic research, product development, and clinical applications. For decades, n-3 PUFA, especially EPA and DHA, have been supplied by fish oil and seafood. With the continuous increase of global population, awareness about the health benefits of n-3 PUFA, and socioeconomic improvement worldwide, the supply chain is facing increasing challenges of insufficient production. In this regard, microalgae have been well considered as promising sources of n-3 PUFA oil to mitigate the supply shortages. The use of microalgae to produce n-3 PUFA-rich oils has been explored for over two decades and some species have already been used commercially to produce n-3 PUFA, in particular EPA- and/or DHA-rich oils. In addition to n-3 PUFA, microalgae biomass contains many other high value biomolecules, which can be used in food, dietary supplement, pharmaceutical ingredient, and feedstock. The present review covers the health benefits of n-3 PUFA, EPA, and DHA, with particular attention given to the various approaches attempted in the nutritional interventions using EPA and DHA alone or combined with other nutrients and bioactive compounds towards improved health conditions in people with mild cognitive impairment and Alzheimer's disease. It also covers the applications of microalgae n-3 PUFA in food and dietary supplement sectors and the economic and environmental sustainability of using microalgae as a platform for n-3 PUFA-rich oil production.

Influence of Feeding Weaned Piglets with Laminaria digitata on the Quality and Nutritional Value of Meat

Laminaria digitata is a novel feedstuff that can be used in pig diets to replace conventional feedstuffs. However, its resilient cell wall can prevent the monogastric digestive system from accessing intracellular nutrients. Carbohydrate-active enzyme (CAZyme) supplementation is a putative solution for this problem, degrading the cell wall during digestion. The objective of this work was to evaluate the effect of 10% L. digitata feed inclusion and CAZyme supplementation on the meat quality and nutritional value of weaned piglets. Forty weaned piglets were randomly allocated to four experimental groups (n = 10): control, LA (10% L. digitata, replacing the control diet), LAR (LA + CAZyme (0.005% Rovabio® Excel AP)) and LAL (LA + CAZyme (0.01% alginate lyase)) and the trial lasted for two weeks. The diets had no effect on any zootechnical parameters measured (p > 0.05) and meat quality traits, except for the pH measured 24 h post-mortem, which was higher in LAL compared to LA (p = 0.016). Piglets fed with seaweed had a significantly lower n-6/n-3 PUFA ratio compared to control, to which the higher accumulation of C20:5n-3 (p = 0.001) and C18:4n-3 (p < 0.0001) contributed. In addition, meat of seaweed-fed piglets was enriched with bromine (Br, p < 0.001) and iodine (I, p < 0.001) and depicted a higher oxidative stability. This study demonstrates that the nutritional value of piglets’ meat could be improved by the dietary incorporation of L. digitata, regardless of CAZyme supplementation, without negatively affecting growth performance in the post-weaning stage.

Microalgae: Potential for Bioeconomy in Food Systems

The efficient use of natural resources is essential for the planet’s sustainability and ensuring food security. Colombia’s large availability of water resources in combination with its climatic characteristics allows for the development of many microalgae species. The use of microalgae can potentially contribute to sustainable production in support of the agri-food sector. The nutritional composition (proteins, carbohydrates, fatty acids, vitamins, pigments, and antioxidants) of microalgae along with the ease of producing high biomass yields make them an excellent choice for human and animal nutrition and agriculture. Several species of microalgae have been studied seeking to develop food supplements for pigs, ruminants, poultry, fish, crustaceans, rabbits, and even bees. Important benefits to animal health, production, and improved bromatological and organoleptic characteristics of milk, meat, and eggs have been observed. Based on the functional properties of some microalgae species, foods and supplements have also been developed for human nutrition. Moreover, because microalgae contain essential nutrients, they can be utilized as biofertilizers by replacing chemical fertilizers, which are detrimental to the environment. In view of the above, the study of microalgae is a promising research area for the development of biotechnology and bioeconomy in Colombia.

Using Microalgae as a Sustainable Feed Resource to Enhance Quality and Nutritional Value of Pork and Poultry Meat

Cereal grains and soybean meal are the main feedstuffs used in swine and poultry feeding, two of the most consumed meats and of key relevance to food security worldwide. Such crops are grown mostly in North and South America and transported over large distances creating sustainability concerns and, furthermore, are in direct competition with human nutrition. Alternatives to these ingredients are, thus, a pressing need to ensure the sustainability of swine and poultry production. Microalgae seem to be a viable alternative due to their interesting nutritional composition. The use of different microalgae in monogastric feeding has been addressed by different researchers over the last decade, particularly their use as a supplement, whilst their use as a feed ingredient has been comparatively less studied. In addition, the high production costs of microalgae are a barrier and prevent higher dietary inclusion. Studies on the effect of microalgae on meat quality refer mostly to fatty acid composition, using these either as a functional ingredient or as a feedstuff. Within such a context and in line with such a rationale, in this review we address the current research on the topic of the use of microalgae in poultry and swine nutrition, particularly aspects concerning pork and poultry meat quality and nutritional traits.

Bioremediation role of Spirulina platensis against deltamethrin-mediated toxicity and its chemical residues in chicken meat

Deltamethrin (DM) is a synthetic pyrethroid insecticide commonly used in veterinary and agriculture. However, both animal and human exposure are associated with hepatorenal toxicity. Our experimental goal was to assess the protective effects of Spirulina platensis (SP) against DM-induced hepatorenal injury, growth performance, meat chemical composition, and its residues in meat, liver, and skin of broiler chickens. Sixty 1-day-old Cobb broiler chicks were assigned to 4 experimental groups; each was divided into 3 replicates with five chicks each; the 1st group received basal diet alone (control), 2nd group supplemented with SP 20 g/kg diet, 3rd group supplemented with DM 300 mg/kg diet, and 4th group supplemented with DM and SP diet. All groups have received the treatment for 35 days. DM, decreased body weight, weight gain, and increased feed conversion rate. DM showed a significant increase in ALT, AST, urea, creatinine, and MDA and a significant decrease in SOD, and GSH levels. Also, SP significantly reduced DM levels in meat, skin, and liver with a reduction 63.01, 63.00, and 62.90 %, respectively. The DM intoxicated group showed a significant decrease in protein and a marked increase in fat, cholesterol, and triglycerides when compared to the control group. Histopathological changes were also recorded. Dietary SP improved these parameters. Dietary inclusion of SP can be recommended due to the protective effects on DM-induced toxicity in broiler chickens.

Fatty Acid Composition of Meat Animals as Flavor Precursors

This article provides an overview of fatty acids in meat, their variation among animal species, and the roles of fatty acids as flavor precursors. Animal fat mostly consists of triglycerides and phospholipids. Fats from ruminant (cattle, sheep, and goats) and monogastric (pigs and horses) animals have similar fatty acids with more saturated fatty acids and monounsaturated fatty acids than polyunsaturated fatty acids. In monogastric animals, fatty acids in the muscle reflect the composition of diets, whereas ruminant fatty acids are more saturated because of biohydrogenation in the rumen. Lipid- derived flavor compounds are formed from the thermal oxidation of fatty acids during cooking, producing more desirable aromatic compounds than autoxidation. Monounsaturated fatty acids such as oleic acid and polyunsaturated fatty acids such as linoleic acid in meat produce various volatile compounds contributing to cooked meat aromas. Under most cooking conditions, lipid-derived flavor compounds are usually predominant. However, these compounds have greater thresholds than those derived from water-soluble compounds, such as the Maillard reaction products. The interactions between lipid oxidation products and Maillard compounds are more important for the development of meat flavor than originally thought. Moreover, fat-derived volatile compounds provide flavor notes indicative of species identification.

A viewpoint on the use of microalgae as an alternative feedstuff in the context of pig and poultry feeding-a special emphasis on tropical regions

With the current increase in meat and animal products consumption, there is a need to make production systems more sustainable. The use of microalgae in monogastric feeds, replacing widely used conventional feedstuffs such corn and soybean, can be a solution to overcome this problem. Several studies have shown promising results in the use of microalgae in feeding of both pigs and poultry. However, there are several important constraints associated to the production of microalgae. Such constraints are particularly limiting in the context of tropical regions. Research and scientific development on microalgae production systems are thus essential so that may be widely used in monogastric feeding. Herein, we conduct an overview of the major findings in the use of microalgae in the context of monogastric feeding and analyse the major constraints associated to its production and use, particularly in the specific context of tropical regions.

Phyco-remediation of swine wastewater as a sustainable model based on circular economy

Pork production has expanded in the world in recent years. This growth has caused a significant increase in waste from this industry, especially of wastewater. Although there has been an increase in wastewater treatment, there is a lack of useful technologies for the treatment of wastewater from the pork industry. Swine farms generate high amounts of organic pollution, with large amounts of nitrogen and phosphorus with final destination into water bodies. Sadly, little attention has been devoted to animal wastes, which are currently treated in simple systems, such as stabilization ponds or just discharged to the environment without previous treatment. This uncontrolled release of swine wastewater is a major cause of eutrophication processes. Among the possible treatments, phyco-remediation seems to be a sustainable and environmentally friendly option of removing compounds from wastewater such as nitrogen, phosphorus, and some metal ions. Several studies have demonstrated the feasibility of treating swine wastewater using different microalgae species. Nevertheless, the practicability of applying this procedure at pilot-scale has not been explored before as an integrated process. This work presents an overview of the technological applications of microalgae for the treatment of wastewater from swine farms and the by-products (pigments, polysaccharides, lipids, proteins) and services of commercial interest (biodiesel, biohydrogen, bioelectricity, biogas) generated during this process. Furthermore, the environmental benefits while applying microalgae technologies are discussed.

Effects of Supplementation of Microalgae (Aurantiochytrium sp.) to Laying Hen Diets on Fatty Acid Content, Health Lipid Indices, Oxidative Stability, and Quality Attributes of Meat

The present study is conducted to investigate the effects of dietary docosahexaenoic acid (DHA)-rich microalgae (MA, Aurantiochytrium sp.) on health lipid indices, stability, and quality properties of meat from laying hens. A total of 450 healthy 50-wk-old Hy-Line Brown layers were randomly allotted to 5 groups (6 replicates of 15 birds each), which received diets supplemented with 0, 0.5, 1.0, 1.5, and 2.0% MA for 15 weeks. Fatty acid contents and quality properties of breast and thigh muscles from two randomly selected birds per replicate (n = 12) were measured. The oxidative stability of fresh, refrigerated, frozen, and cooked meat was also determined. Results indicated that supplemental MA produced dose-dependent enrichments of long-chain n-3 polyunsaturated fatty acids (n-3 LC-PUFA), predominantly DHA, in breast and thigh muscles, with more health-promoting n-6/n-3 ratios (1.87-5.27) and favorable lipid health indices (p < 0.05). MA supplementation did not affect tenderness (shear force) and color (L*, a*, and b* values) of hen meat nor muscle endogenous antioxidant enzymes and fresh meat oxidation (p > 0.05). However, the n-3 LC-PUFA deposition slightly increased lipid oxidation in cooked and stored (4 °C) meat (p < 0.05). In conclusion, MA supplementation improves the nutritional quality of hen meat in terms of lipid profile without compromising meat quality attributes. Appropriate antioxidants are required to mitigate oxidation when such DHA-enriched meat is subjected to cooking and storage.

Effects of dietary fat saturation level on growth performance, carcass traits, blood lipid parameters, tissue fatty acid composition and meat quality of finishing pigs

Objective

The objective of this study was to investigate the effects of various dietary unsaturated to saturated fatty acids ratios (UFA to SFA ratios) on growth performance, carcass traits, blood lipid parameters, tissue fatty acid (FA) composition, and meat quality of finishing pigs.

Methods

A total of 45 crossbred pigs ([Duroc×Landrace]×Yorkshire), with an average initial body weight of 60.3±2.4 kg, were randomly allocated to three treatment groups of 1:1, 2:1, and 3:1 dietary UFA to SFA ratios.

Results

Both average daily gain and average daily feed intake of pigs were decreased linearly (p<0.05), whereas backfat thickness was decreased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Serum triglyceride and low density lipoprotein cholesterol were decreased quadratically or linearly (p<0.05) respectively, whereas high density lipoprotein cholesterol was increased quadratically (p<0.05) with increasing dietary UFA to SFA ratio. In M. longissimus thoracis, the proportion of C18:1 and monounsaturated FA was decreased linearly (p<0.05), whereas the proportion of C18:2n-6, C20:4n-6 and polyunsaturated FA (PUFA) were increased linearly (p<0.05) as dietary UFA to SFA ratio increased. In the subcutaneous adipose tissue, the proportion of SFA was decreased linearly (p<0.05), whereas the proportion of n-6 PUFA, n-3 PUFA, and the UFA to SFA ratios were increased linearly (p<0.05) with increasing of dietary UFA to SFA ratio. Meat color scores and shear force of pigs were decreased linearly (p<0.05), whereas drip loss and cooking loss were increased linearly (p<0.05) with increasing of dietary UFA to SFA ratio.

Conclusion

Appropriately boosted dietary UFA to SFA ratio could be conductive to optimize blood lipid parameters and tissue FA composition. However, when the ratio is too high or too low it tends to have negative effects on growth performance and meat quality.

Effects of long-term microalgae supplementation on muscle microstructure, meat quality and fatty acid composition in growing pigs

We investigated the effects of long-term microalgae supplementation (7% in a piglet diet and 5% in a fattening diet) on muscle microstructure and meat quality, including fatty acid composition in female Landrace pigs (n = 31). The major effects were muscle-specific increases in n-3 and n-6 polyunsaturated fatty acids (PUFA) concentrations, resulting in increased accumulation of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Carcass traits and meat quality of longissimus thoracis muscle were not affected by the microalgae diet with the exception of reduced drip loss (p = 0.01) and increased protein proportion (p = 0.04). In addition, the microalgae diet resulted in a shift to a more oxidative myofibre type composition in semitendinosus but not longissimus thoracis muscle. In conclusion, microalgae supplementation offers a unique opportunity to enhance essential n-3 PUFA contents in pig meat. The results support small but coordinated changes in skeletal muscle phenotypic appearance and functionality.