n-3 PUFA Sources (Precursor/Products): A Review of Current Knowledge on Rabbit

The Effect of Dietary Plant-Derived Omega 3 Fatty Acids on the Reproductive Performance and Gastrointestinal Health of Female Rabbits

This study examined the effects of extruded linseed and algae Padina pavonica extract on the reproductive performance, milk production, and gastrointestinal health of female rabbits. Thirty-six nulliparous New Zealand White female rabbits were randomly assigned to three groups (n = 12) with different diets. The control group (CNT) received a standard diet, while the other two groups received modified isoenergetic diets in which part of the CNT diet ingredients were replaced with 5% extruded linseed (L5%) and 5% extruded linseed plus 0.2% Padina pavonica algae extract (L5%PP). The rabbits were monitored from artificial insemination until the weaning of the rabbit kits, evaluating different reproductive parameters. Our results indicate that extruded linseed and alga Padina pavonica extract did not affect the feed intake or body weight of female rabbits. Additionally, no clinically significant histological changes were observed at the gastrointestinal level. The reproductive parameters, including litter size, litter weight, and milk yield, showed no significant differences among groups. Notably, perinatal and pre-weaning mortalities were reduced in litters born to females receiving omega-3 integrated diets (p < 0.05). While these findings are promising, further studies are needed to confirm these results and explore the specific mechanisms by which omega-3 affects reproductive function and litter health.

Gut microbiota is involved in male reproductive function: a review

Globally, ~8%-12% of couples confront infertility issues, male-related issues being accountable for 50%. This review focuses on the influence of gut microbiota and their metabolites on the male reproductive system from five perspectives: sperm quality, testicular structure, sex hormones, sexual behavior, and probiotic supplementation. To improve sperm quality, gut microbiota can secrete metabolites by themselves or regulate host metabolites. Endotoxemia is a key factor in testicular structure damage that causes orchitis and disrupts the blood-testis barrier (BTB). In addition, the gut microbiota can regulate sex hormone levels by participating in the synthesis of sex hormone-related enzymes directly and participating in the enterohepatic circulation of sex hormones, and affect the hypothalamic-pituitary-testis (HPT) axis. They can also activate areas of the brain that control sexual arousal and behavior through metabolites. Probiotic supplementation can improve male reproductive function. Therefore, the gut microbiota may affect male reproductive function and behavior; however, further research is needed to better understand the mechanisms underlying microbiota-mediated male infertility.

Molecular Mechanisms Associated with the Inhibitory Role of Long Chain n-3 PUFA in Colorectal Cancer

Colorectal cancer (CRC) is the third leading cause of cancer-related death in the world. Multiple evidence suggests that there is an association between excess fat consumption and the risk of CRC. The long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential for human health, and both in vitro and in vivo studies have shown that these fatty acids can prevent CRC development through various molecular mechanisms. These include the modulation of arachidonic acid (AA) derived prostaglandin synthesis, alteration of growth signaling pathways, arrest of the cell cycle, induction of cell apoptosis, suppression of angiogenesis and modulation of inflammatory response. Human clinical studies found that LC n-3 PUFA combined with chemotherapeutic agents can improve the efficacy of treatment and reduce the dosage of chemotherapy and associated side effects. In this review, we discuss comprehensively the anti-cancer effects of LC n-3 PUFA on CRC, with a main focus on the underlying molecular mechanisms.

Exploring the Antioxidant Potential of Blackberry and Raspberry Leaves: Phytochemical Analysis, Scavenging Activity, and In Vitro Polyphenol Bioaccessibility

The goal of this research was nutritional evaluation through the phytochemical analysis of blackberry and raspberry leaves, the screening of their biological activity (antioxidant capacity and inhibition of lipid peroxidation), and the investigation of the effect of in vitro gastrointestinal digestion (GID) of blackberry and raspberry leaves on the bioaccessibility of polyphenol subclasses. The concentrations of the analyzed liposoluble antioxidants were higher (p < 0.05) in blackberry leaves compared to raspberry leaves, while a significant (p < 0.05) higher content of water-soluble antioxidants was registered in raspberry leaves (with a total polyphenol content of 26.2 mg GAE/g DW of which flavonoids accounted for 10.6 mg/g DW). Blackberry leaves had the highest antioxidant capacity inhibition of the superoxide radicals (O2•-), while raspberry leaves registered the highest inhibition of hydroxyl radicals (•OH), suggesting a high biological potency in scavenging-free radicals under in vitro systems. The maximum inhibition percentage of lipid peroxidation was obtained for blackberry leaves (24.86% compared to 4.37% in raspberry leaves), suggesting its potential to limit oxidative reactions. Simulated in vitro digestion showed that hydroxybenzoic acids registered the highest bioaccessibility index in the intestinal phase of both types of leaves, with gallic acid being one of the most bioaccessible phenolics. The outcomes of this investigation reveal that the most significant release of phenolic compounds from blackberry and raspberry leaves occurs either during or after the gastric phase. Knowledge about the bioaccessibility and stability of polyphenol compounds during digestion can provide significant insights into the bioavailability of these molecules and the possible effectiveness of plant metabolites for human health.

Pro-Atherogenic and Pro-Oxidant Diets Influence Semen and Blood Traits of Rabbit Bucks

Many dietary factors can affect sperm traits. We compared the effect of diets rich in pro-oxidant (flaxseed oil) and pro-atherogenic (coconut oil) substances without added antioxidants on semen traits, using the rabbit as an animal model. Thirty rabbit bucks (8 months old) were fed three diets for 150 days: CNT (control) a standard diet; HA (high-atherogenic) standard diet + 3% coconut oil, and HO (high-oxidizing) standard diet + 3% flaxseed oil. Semen samples were collected weekly for the evaluation of qualitative traits (kinetics, viability) and the oxidative damage (MDA and cytokines). Blood was collected at the start (T0) and end (T8) of the experimental period for the assessment of the oxidative damage (MDA and isoprostanoids), lipid profile, and testosterone. A worsening of sperm kinetics and viability was recorded in the HA group. Lipid oxidation in seminal plasma, as well as isoprostanoids in blood (F3-IsoPs and F4-NeuroPs), increased in both the HO and HA groups. A high level of TNF-α, a marker of inflammatory status, was recorded in the seminal plasma of the HA group. The resulting outcomes were mainly attributable to the different fatty acid profiles (SFA vs. PUFA) of the diets, which modulated an inflammatory/oxidative response.

Antioxidant Activity, Metabolism, and Bioavailability of Polyphenols in the Diet of Animals

As the world’s population grows, so does the need for more and more animal feed. In 2006, the EU banned the use of antibiotics and other chemicals in order to reduce chemical residues in food consumed by humans. It is well known that oxidative stress and inflammatory processes must be combated to achieve higher productivity. The adverse effects of the use of pharmaceuticals and other synthetic compounds on animal health and product quality and safety have increased interest in phytocompounds. With the use of plant polyphenols in animal nutrition, they are gaining more attention as a supplement to animal feed. Livestock feeding based on a sustainable, environmentally friendly approach (clean, safe, and green agriculture) would also be a win–win for farmers and society. There is an increasing interest in producing healthier products of animal origin with a higher ratio of polyunsaturated fatty acids (PUFAs) to saturated fatty acids by modulating animal nutrition. Secondary plant metabolites (polyphenols) are essential chemical compounds for plant physiology as they are involved in various functions such as growth, pigmentation, and resistance to pathogenic organisms. Polyphenols are exogenous antioxidants that act as one of the first lines of cell defense. Therefore, the discoveries on the intracellular antioxidant activity of polyphenols as a plant supplement have contributed significantly to the improvement of antioxidant activity, as polyphenols prevent oxidative stress damage and eliminate excessively produced free radicals. To achieve animal welfare, reduce stress and the need for medicines, and increase the quality of food of animal origin, the addition of polyphenols to research and breeding can be practised in part with a free-choice approach to animal nutrition.

Alternative microbial-based functional ingredient source for lycopene, beta-carotene, and polyunsaturated fatty acids

The acquisition of carotenoids and polyunsaturated fatty acids (PUFAs) from plants and animals for use as functional ingredients raises concerns regarding productivity and cost; utilization of microorganisms as alternative sources is an option. We proposed to evaluate the production of carotenoids and PUFAs by Rhodopseudomonas faecalis PA2 using different vegetable oils (rice bran oil, palm oil, coconut oil, and soybean oil) as carbon source, different concentrations of yeast extract as nitrogen source at different cultivation time to ensure the best production. Cultivation with soybean oil as source of carbon led to the most significant changes in the fatty acid profile. Compared to the initial condition, the strain cultivated in the optimal conditions (4% soybean oil, 0.35% yeast extract, and 14 days of incubation) showed an increase in μ_max, biomass, carotenoid productivity, and microbial lipids by 102.5%, 52.7%, 33.82%, and 34.78%, respectively. The unsaturated fatty acids content was raised with additional types of PUFAs; omega-3 [alpha-linolenic acid and eicosapentaenoic acid] and omega-6 [linoleic acid and eicosatrienoic acid] fatty acids were identified. The results of ultra high-performance liquid chromatography-electrospray ionization-quadrupole time of flight-mass spectrometry (UHPLC-ESI-QTOF-MS/MS) indicated the molecular formula and mass of bacterial metabolites were identical to those of lycopene and beta-carotene. The untargeted metabolomics revealed functional lipids and several physiologically bioactive compounds. The outcome provides scientific reference regarding carotenoids, PUFAs, and useful metabolites that have not yet been reported in the species Rhodopseudomonas faecalis for further use as a microbial-based functional ingredient.

Properties of Polyunsaturated Fatty Acids in Primary and Secondary Prevention of Cardiovascular Diseases in the View of Patients (Silesia, Poland)

BACKGROUND

Cardiovascular diseases are a major cause of morbidity and mortality in Europe. Lifestyle plays an important role in the primary and secondary prevention of cardiovascular diseases, apart from pharmacotherapy and diagnostics. Numerous studies confirm that the type and quality of fat consumed in the diet have a huge impact on the risk of cardiovascular diseases. Reducing the risk of cardiovascular disease can be helped by minimizing the proportion of saturated fatty acids in the diet and replacing them with polyunsaturated fatty acids. These acids and, above all, their long-chain forms have a positive effect on health.

AIM

This study aims to assess the awareness of the properties of polyunsaturated fatty acids in the primary and secondary prevention of cardiovascular diseases in the opinions of patients of the Cardiology Department of the Racibórz Medical Center.

MATERIAL AND METHODS

The analysis included 302 patients (113 women and 189 men) hospitalized in the Cardiology Department. The research method was the authors' questionnaire consisting of the patients' record and thirty closed questions. To answer the research questions posed and test the hypotheses, statistical analyses were carried out using the IBM SPSS Statistics version 25 package.

RESULTS

Among the respondents, the least frequently used healthy eating habit was the infrequent eating of fried foods. A total of 18.2% of respondents had such a habit. The most commonly used healthy eating habit was checking the fat content in products, which was performed by 67.2% of respondents. Among the respondents, 58.3% said that butter and margarine increase serum cholesterol.

CONCLUSIONS

The analysis of the data shows that the place of residence, education, sex, and reason for hospitalization of the respondents did not affect the frequency of healthy eating habits. In addition, the subjects had a low amount of healthy eating habits.

Indexing of Fatty Acids in Poultry Meat for Its Characterization in Healthy Human Nutrition: A Comprehensive Application of the Scientific Literature and New Proposals

Chicken meat is becoming the most consumed in the world for both economic and nutritional reasons; regarding the latter, the lipid profile may play positive or negative roles in the prevention and treatment of diseases. In this study, we define the state of the art of lipid-based nutritional indexes and used the lipid content and fatty acid profile (both qualitative and quantitative) of breast meat of two poultry genotypes with different growth rates and meat traits. Further, we summarize and review the definitions, implications, and applications of nutritional indexes used in recent years and others of our own design to provide a useful tool to researchers working in the field of meat quality (not only in poultry) to select the most appropriate index for their own scientific purposes. All indexes show advantages and disadvantages; hence, a rational choice should be applied to consider the nutritional effect of meat on human health and for a possible assessment of the most suitable rearing systems (genotype, feeding, farming system or postmortem handling).

Poultry Meat and Eggs as an Alternative Source of n-3 Long-Chain Polyunsaturated Fatty Acids for Human Nutrition

The beneficial effects of n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) on human health are widely known. Humans are rather inefficient in synthesizing n-3 LC-PUFA; thus, these compounds should be supplemented in the diet. However, most Western human diets have unbalanced n-6/n-3 ratios resulting from eating habits and the fact that fish sources (rich in n-3 LC-PUFA) are not sufficient (worldwide deficit ~347,956 t/y) to meet the world requirements. In this context, it is necessary to find new and sustainable sources of n-3 LC-PUFA. Poultry products can provide humans n-3 LC-PUFA due to physiological characteristics and the wide consumption of meat and eggs. The present work aims to provide a general overview of the main strategies that should be adopted during rearing and postproduction to enrich and preserve n-3 LC-PUFA in poultry products. The strategies include dietary supplementation of α-Linolenic acid (ALA) or n-3 LC-PUFA, or enhancing n-3 LC-PUFA by improving the LA (Linoleic acid)/ALA ratio and antioxidant concentrations. Moreover, factors such as genotype, rearing system, transport, and cooking processes can impact the n-3 LC-PUFA in poultry products. The use of a multifactorial view in the entire production chain allows the relevant enrichment and preservation of n-3 LC-PUFA in poultry products.

Improving Rabbit Doe Metabolism and Whole Reproductive Cycle Outcomes via Fatty Acid-Rich Moringa oleifera Leaf Extract Supplementation in Free and Nano-Encapsulated Forms

Simple Summary

Under intensive rabbit production systems, due to the increased energy requirements of reproductive events, specifically pregnancy and lactation, rabbit does may confront several metabolic disorders as a result of energy imbalance. Moringa oleifera leaf ethanolic extract (ME) is one of the phytogenic extracts that has an impressive range of phytochemicals, specifically fatty acids (FAs). These phytochemicals may be biologically effective to support metabolism and reproductive functions of rabbit does during different reproductive cycle events. However, the high FAs content of ME makes them highly susceptible to lipid oxidation, diminishing their nutritional value and biological effects. In this study, we aimed to test the effects of FAs of ME either in a free-from or in a nano-encapsulated form on metabolism, immunity, milk production, milk composition, and reproductive performance of rabbit does during different physiological status (premating, mating, pregnancy, and lactation). The results showed that ME improved health, metabolism, immune functions, milk production and composition, and reproductive performance of rabbit does. These effects remained obvious even when a lower dose of ME was used in a nano-encapsulated form.

Abstract

The effects of free and nano-encapsulated ME supplementations on the metabolism, immunity, milk production and composition, and reproductive performance of rabbit does during premating, mating, pregnancy, and lactation were investigated. Multiparous rabbit does (n = 26 per group) received 50 mg of free ME (FME) daily, 25 mg of nano-encapsulated ME (HNME), or 10 mg of nano-encapsulated ME (LNME) per kilogram of body weight or were not supplemented (C) during a whole reproductive cycle. The ME contained 30 fatty acids with 54.27% total unsaturated fatty acids (USFAs). The fatty acid encapsulation efficiency of alginate nanoparticles was 70.46%. Compared with the C group, rabbits in all ME treatments had significantly increased body weight, feed intake, and glucose concentration and significantly decreased non-esterified free fatty acids and β-hydroxybutyrate concentrations. Rabbits supplemented with ME also had significantly increased white blood cell counts, phagocytic activity, lysozyme activity, and immunoglobulin G and decreased interleukin-1β concentrations. Moreover, ME supplementation significantly increased the concentrations of colostrum immunoglobulins, milk yield and energy content, and milk USFAs (omega-3 and 6). Rabbit does in the ME treatments had significantly higher conception and parturition rates and better litter characteristics than the C rabbit does. These results demonstrate the positive role of ME fatty acids on the health status and productive and reproductive performance of rabbit does at different physiological stages. Compared with the FME treatment, these parameters were further improved in rabbits that received nano-encapsulated ME at lower doses, illustrating how nano-encapsulation technology improves the bioavailability of ME.

A Dynamic Model for Estimating the Interaction of ROS–PUFA–Antioxidants in Rabbit

Defining optimal nutrition in animals and humans remains a main scientific challenge. The objective of the work was to develop a dynamic model of reactive oxygen species (ROS)–polyunsaturated fatty acid (PUFA)–antioxidant homeostasis using the rabbit as a model. The problem entity was to evaluate the main metabolites generated from interactions between traits included in the conceptual model and identified by three main sub–models: (i) ROS generation, (ii) PUFA oxidation and (iii) antioxidant defence. A mathematical model (VENSIM software) that consisted of molecular stocks (INPUTs, OUTPUTs), exchange flows (intermediate OUTPUTs) and process rates was developed. The calibration was performed by using standard experimental data (Experiment 1), whereas the validation was carried out in Experiments 2 and 3 by using supra–nutritional dietary inputs (VIT E+ and PUFA+). The accuracy of the models was measured using 95% confidence intervals. Analytical OUTPUTs (ROS, PUFA, Vit E, Ascorbic acid, Iso–/NeuroProstanes, Aldehydes) were well described by the standard model. There was also good accuracy for the VIT E+ scenario, whereas some compensatory rates (Kc1–Kc4) were added to assess body compensation when high levels of dietary PUFA were administered (Experiment 3). In conclusion, the model can be very useful for predicting the effects of dietary treatments on the redox homeostasis of rabbits.

Expression of genes and localization of enzymes involved in polyunsaturated fatty acid synthesis in rabbit testis and epididymis

The metabolism of polyunsaturated fatty acids (PUFAs) plays an important role in male reproduction. Linoleic and alpha-linolenic acids need to be provided in the diet and they are converted into long chain polyunsaturated fatty acids by steps of elongation and desaturation, exerted by elongases 2 (ELOVL2) and 5 (ELOVL5) and Δ5- (FADS1) and Δ6-desaturase (FADS2). This study aims to assess the gene expression and localization of enzymes involved in the synthesis of n-3 and n-6 long-chain PUFAs in control rabbits and those fed diets containing 10% extruded flaxseed. Enzyme and PUFA localization were assessed in the testes and epididymis by immunofluorescence. Testes showed high gene expression of FADS2, ELOVL2 and ELOVL5 and low expression of FADS1. Intermediate metabolites, enzymes and final products were differently found in Leydig, Sertoli and germinal cells. FADS2 was localized in interstitial cells and elongated spermatids; ELOVL5 in meiotic cells; FADS1 was evident in interstitial tissue, Sertoli cells and elongated spermatids; ELOVL2 in interstitial cells. Epididymal vesicles were positive for FADS1, ELOVL2 and ELOVL5 as well as docosahexaenoic, eicosapentaenoic, and arachidonic acids. This knowledge of fatty acids (FA) metabolism in spermatogenesis and the influence of diet on FA profile could help identify causes of male infertility, suggesting new personalized therapy.

Could Dietary Supplementation with Different Sources of N-3 Polyunsaturated Fatty Acids Modify the Rabbit Gut Microbiota?

The present study evaluated the effects of feed supplemented with two dietary sources of n-3 polyunsaturated fatty acids (PUFAs; fish oil and extruded flaxseed) on the gut microbiota, caecal fermentations, gastrointestinal histology, and histochemistry in rabbits. Fifteen male New Zealand White rabbits were divided into three groups (n = 5/group) and fed with different diets from weaning (35 days of age) until slaughtering (90 days of age): C group, fed with a commercial diet; F group, supplemented with 10% of extruded flaxseed; and O group, supplemented with 3.5% of fish oil. At slaughter, the content of the stomach, duodenum, jejunum, ileum, caecum, and colon was collected and analyzed by Next Generation 16S rRNA gene sequencing. Tissue samples of the same tracts were evaluated with histological and histochemical analysis. Ammonia and lactic acid in the caecum were also quantified. Twenty-nine operational taxonomic units (OTUs) were significantly different between groups. Groups receiving n-3 PUFAs supplementation showed an increase in Bacteroidetes and Lachnospiraceae in several gastrointestinal tracts, while Bacilli abundance, as well as Firmicutes/Bacteroidetes ratio, were reduced compared to the control group (for all p < 0.05). Caecal ammonia was lower in the F than C group (p < 0.032), whereas no difference was found for lactic acid. Finally, histological evaluations revealed a mild hemorrhagic infiltration and vessels ectasia in the stomach mucosa of both F and O groups, but no effect of nutritional treatment was evidenced by the histochemical analyses. In conclusion, n-3 PUFAs supplementation could modify the rabbit gut microbiota and fermentation. The increase in beneficial bacterial populations may, at least partially, explain the positive effects of n-3 PUFAs diet supplementation on human and animals’ health, although the appropriate dosage should be established.

Fatty Acid Profile of Blood Plasma at Mating and Early Gestation in Rabbit

The aim of this study was to analyse the fatty acid (FA) profile of blood plasma at mating and 72 hpm by gas chromatography. Moreover, the correlation between FA and ovulation rate, normal embryos and compacted morulae was estimated. Palmitic, linoleic, oleic and stearic were the highest FA concentrations at mating and 72 hpm. Most long chain saturated and PUFA were higher at 72 hpm than at mating, while MUFA were higher at mating. SFA, MUFA and PUFA were high and positively correlated. Correlation was 0.643 between MUFA at mating and ovulation rate, and 0.781 between MUFA and normal embryos, respectively. Compacted morulae were slightly correlated with SFA at mating (0.465). In conclusion, the FA profile of plasma varies depending on the reproductive cycle of the rabbit female, adapting to energetic requirements at mating and early gestation. Moreover, positive correlations are found between fatty acids and ovulation rate and embryo development and quality.

The influence of vegetarian and vegan diets on the state of bone mineral density in humans

There are so many literatures about vegetarians being less prone to chronic, noninfectious diseases, which are, however, the main cause of the decline in quality of life and mortality in developed countries.However, according to various scientific sources, vegetarian and especially vegan diets often contain less saturated fats, protein, calcium, vitamins D and B12, or long-chain ω-3 PUFAs. One of the most common pathology associated with a predominantly plant diet is osteopenia and osteoporosis. An analysis of 13 studies has shown that vegetarians and vegans are at a higher risk of reducing of bone mineral density, thereby increasing the incidence of fractures.At the same time, plant-based diets are usually richer in many other micronutrients important for bone health: vitamins C and K, carotenoids, potassium, magnesium, manganese, copper, or silicon. Moreover, with the deepening of our knowledge about the role of nutrients in the body and the features of the nutritional status of the population, the quality of vegetarian and vegan diets also increases. They are less and less prone to micronutrient deficiencies. Recent studies show that BMD, as well as the risk of osteoporotic fractures, at least in vegetarians, equaled these indicators in omnivores.

Immunity boosting nutraceuticals: Current trends and challenges

The immune function of the human body is highly influenced by the dietary intake of certain nutrients and bioactive compounds present in foods. The preventive effects of these bioactive ingredients against various diseases have been well investigated. Functional foods are consumed across various diverse cultures, in some form or the other, which provide benefits greater than the basic nutritional needs. Novel functional foods are being developed using novel bioactive ingredients such as probiotics, polyunsaturated fatty acids, and various phytoconstituents, which have a range of immunomodulatory properties. Apart from immunomodulation, these ingredients also affect immunity by their antioxidant, antibacterial, and antiviral properties. The global pandemic of Severe Acute Respiratory Syndrome Coronavirus-2 has forced the scientific community to race against time to find a proper and effective drug or a vaccine. In this review, various non-pharmacological interventions using nutraceuticals and functional foods have been discussed. PRACTICAL APPLICATIONS: Despite a plethora of research being undertaken to understand the immunity boosting properties of the various bioactive present in food, the findings are not translating to nutraceutical products in the market. Immunity has proved to be one of the most important factors for the health and well-being of an individual, especially when the world has been under the grip of the novel coronavirus Severe Acute Respiratory Syndrome Coronavirus-2. The anti-inflammatory properties of various nutraceuticals can come out as potential inhibitors of the various inflammatory processes such as cytokine storms, usually being observed in COVID 19. This review gives an insight into how various nutraceuticals can help in the prevention of various diseases through different mechanisms. The lack of awareness and proper clinical trials pose a challenge to the nutraceutical industry. This review will help and encourage researchers to further design and develop various functional foods, which might help in building immunity.

Tissue Antioxidant Status and Lipid Peroxidation Are Related to Dietary Intake of n-3 Polyunsaturated Acids: A Rabbit Model

Polyunsaturated fatty acid (PUFA) metabolism and tissue distribution is modulated by the oxidation of these molecules. This research aimed to investigate the implication of dietary n-3 PUFA supplementation (precursor and long-chain PUFA) on the PUFA profile and oxidative status of the liver, testis, and brain of adult rabbit bucks. Twenty New Zealand White rabbit bucks were divided into four experimental groups (n = 5 per group) and were fed different diets for 110 days: control (CNT), standard diet containing 50 mg/kg alpha-tocopheryl acetate (vitamin E); CNT+, standard diet + 200 mg/kg vitamin E; FLAX, standard diet + 10% flaxseed + 200 mg/kg vitamin E; or FISH, standard diet + 3.5% fish oil + 200 mg/kg vitamin E. Antioxidants (enzymatic and non-enzymatic), oxidative status (malondialdehyde and isoprostanoids), and n-3 and n-6 PUFAs of tissues were analysed. A chain mechanism of oxidant/antioxidant molecules, which largely depended on the particular PUFA composition, was delineated in the different organs. The liver showed an oxidant/antioxidant profile and lipid pathways widely modulated by PUFA and vitamin E administration; on the other hand, the testis' oxidative profile rather than its lipid profile seemed to be particularly affected, an outcome opposite to that of the brain (modulation operated by dietary PUFA).

Perinatal Dietary Polyunsaturated Fatty Acids in Brain Development, Role in Neurodevelopmental Disorders

n-3 and n-6 polyunsaturated fatty acids (PUFAs) are essential fatty acids that are provided by dietary intake. Growing evidence suggests that n-3 and n-6 PUFAs are paramount for brain functions. They constitute crucial elements of cellular membranes, especially in the brain. They are the precursors of several metabolites with different effects on inflammation and neuron outgrowth. Overall, long-chain PUFAs accumulate in the offspring brain during the embryonic and post-natal periods. In this review, we discuss how they accumulate in the developing brain, considering the maternal dietary supply, the polymorphisms of genes involved in their metabolism, and the differences linked to gender. We also report the mechanisms linking their bioavailability in the developing brain, their transfer from the mother to the embryo through the placenta, and their role in brain development. In addition, data on the potential role of altered bioavailability of long-chain n-3 PUFAs in the etiologies of neurodevelopmental diseases, such as autism, attention deficit and hyperactivity disorder, and schizophrenia, are reviewed.

High-Intensity Interval Training and α-Linolenic Acid Supplementation Improve DHA Conversion and Increase the Abundance of Gut Mucosa-Associated Oscillospira Bacteria

Obesity, a major public health problem, is the consequence of an excess of body fat and biological alterations in the adipose tissue. Our aim was to determine whether high-intensity interval training (HIIT) and/or α-linolenic acid supplementation (to equilibrate the n-6/n-3 polyunsaturated fatty acids (PUFA) ratio) might prevent obesity disorders, particularly by modulating the mucosa-associated microbiota. Wistar rats received a low fat diet (LFD; control) or high fat diet (HFD) for 16 weeks to induce obesity. Then, animals in the HFD group were divided in four groups: HFD (control), HFD + linseed oil (LO), HFD + HIIT, HFD + HIIT + LO. In the HIIT groups, rats ran on a treadmill, 4 days.week^-1. Erythrocyte n-3 PUFA content, body composition, inflammation, and intestinal mucosa-associated microbiota composition were assessed after 12 weeks. LO supplementation enhanced α-linolenic acid (ALA) to docosahexaenoic acid (DHA) conversion in erythrocytes, and HIIT potentiated this conversion. Compared with HFD, HIIT limited weight gain, fat mass accumulation, and adipocyte size, whereas LO reduced systemic inflammation. HIIT had the main effect on gut microbiota β-diversity, but the HIIT + LO association significantly increased Oscillospira relative abundance. In our conditions, HIIT had a major effect on body fat mass, whereas HIIT + LO improved ALA conversion to DHA and increased the abundance of Oscillospira bacteria in the microbiota.

Oxidative and/or Inflammatory Thrust Induced by Silver Nanoparticles in Rabbits: Effect of Vitamin E or NSAID Administration on Semen Parameters

The aim of this research was to evaluate the inflammatory and/or oxidative damage related to silver nanoparticles (AgNPs), which are responsible for negative effects on sperm physiology and metabolism. Thirty New Zealand White rabbit bucks were divided into 5 experimental groups (6 animals/group): Control, treated with 0.9% NaCl; AgNP, treated with a 5 mM AgNP solution; LPS, treated with 50 g/kg b.w. E. coli LPS; AgNPs + NSAID, treated with an anti-inflammatory drug at 0.2 mg/kg b.w. and 5 mM AgNPs; and AgNPs + Vit E, treated with 0.18 mg/kg b.w. vitamin E and 5 mM AgNPs. Sperm quality and oxidative and inflammatory status were assessed at different times (0-60 days). Two statistical models were built: the first evaluated the effects of AgNPs and LPS (vs. Control), whereas the second evaluated the protective effect of an NSAID and vitamin E against AgNP-induced damage. Three principal component analyses were performed: sperm traits (motility, volume), oxidative status (antioxidants, oxidative metabolites, and redox reactions), and cytokines (TNF-α, IL-8, and IL-6). A negative effect on reproductive traits resulted after NP administration. In particular, an inflammatory/oxidative response took place in the reproductive tract during the first 2-3 wks of AgNP administration (cytokine and oxidative metabolite generation); the inflammatory/oxidative thrust impaired the status of rabbit tissues (seminal plasma, sperm, and blood), inducing a response (increased antioxidant enzymes and redox reactions) at 4-7 wks; oxidative stress, if not totally counteracted, likely induced toxicity in the late phases of AgNP administration (8-9 wks). In conclusion, exposure to silver nanoparticles produced a similar but more persistent effect than that of LPS on rabbit reproductive tissues: AgNP administration triggered a proinflammatory response linked to oxidative thrust, worsening many sperm parameters. However, only anti-inflammatory treatment counteracted the negative effects of AgNPs, whereas vitamin E seemed to act as an adjuvant, attenuating the oxidative cascade.

Characterization of Bacterial Microbiota Composition along the Gastrointestinal Tract in Rabbits

The microbiota is extremely important for the animal's health, but, to date, knowledge on the intestinal microbiota of the rabbit is very limited. This study aimed to describe bacterial populations that inhabit the different gastrointestinal compartments of the rabbit: stomach, duodenum, jejunum, ileum, caecum, and colon. Samples of the luminal content from all compartments of 14 healthy New White Zealand rabbits were collected at slaughter and analyzed using next generation 16S rRNA Gene Sequencing. The findings uncovered considerable differences in the taxonomic levels among the regions of the digestive tract. Firmicutes were the most abundant phylum in all of the sections (45.9%), followed by Bacteroidetes in the large intestine (38.9%) and Euryarchaeota in the foregut (25.9%). Four clusters of bacterial populations were observed along the digestive system: (i) stomach, (ii) duodenum and jejunum, (iii) ileum, and (iv) large intestine. Caecum and colon showed the highest richness and diversity in bacterial species, while the highest variability was found in the upper digestive tract. Knowledge of the physiological microbiota of healthy rabbits could be important for preserving the health and welfare of the host as well as for finding strategies to manipulate the gut microbiota in order to also promote productive performance.

Animal Fats in Rabbit Feeding – A Review

The purpose of this article is to overview the history of feeding rabbits with different types of animal fats, and to discuss their effects on rabbit performance and quality of their products. Other aspects of the inclusion of various animal fats in rabbit diets are also described. This article is based on the analysis of relevant scientific literature and presents animal fats fed to rabbits, such as beef tallow, butter, pork lard, poultry fat, fish oil, krill oil, oil extracted from insect larvae, mixtures of various animal fats, and mixtures of animal and vegetable fats. The reported papers describe the effect of fats on growth performance, lactation, rearing performance, meat quality, and health status of rabbits. It is notable that in many cases, various animal fats were often an integral part of numerous diets or were included in control diets. The presented information demonstrates that animal fat can be fed to rabbits at 2–4% of the diet without negative effects on reproductive performance, growth performance and quality of meat obtained. Rabbits were used as model animals in many studies in which fat was added to balance the diets and to increase their energy value, especially when investigating various cardiovascular and obesity-related diseases.

Review: Practical Use of n-3 Fatty Acids to Improve Reproduction Parameters in the Context of Modern Sow Nutrition

Simple Summary

The use of n-3 fatty acids could have many favourable aspects considering the nutrition of mammals, as can be seen from studies carried out on humans or livestock animals. Concerning large-scale pig farms, the reproduction performance could be made more balanced at a high level by enhancing efficacy and decreasing the ecological footprint of pork production. In this review, we attempt to identify specific periods in the sow production cycle in which the feeding of n-3 fatty acids returns an investment, in addition to demonstrating the importance of the dosage and proportion of n-6 and n-3 fatty acids, originating from different nutritional sources.

Abstract

The effects of long-chain polyunsaturated fatty acids (LC PUFAs) have been frequently investigated in sows because the profitability of pig production depends mainly on reproduction performance. In feeding trials, different sources and doses of n-3 PUFAs-rich feeds were used with various breeds and stages of production; however, a discrepancy in the response of n-3 PUFAs on sow reproduction has been observed. According to the results of the previous studies, n-3 fatty acids can postpone the time of parturition, decreasing the synthesis of prostaglandins, which are necessary for uterus contraction during labour. These effects could also be useful during the post-weaning period when low prostaglandin levels are indispensable for embryo survival. The n-3 fatty acids fed during the lactation period secreted in milk, may improve piglet performance. In this review, we will focus on the contradictory results of previous studies concerning practical swine nutrition. The main purpose of the review is to highlight those periods of swine breeding when the use of n-3 fatty acids may be advantageous in case of the deficiency of these essential nutrients. In finding the appropriate dose of n-3 PUFAs in terms of sow nutrition, the n-6 PUFAs levels in the given feeds must be taken into account to ensure that there are no significant reductions in the final n-6/n-3 ratio. Despite the numerous previous field trials, there are no current feeding recommendations available for PUFAs in swine nutrition. Hence, more research is required in different practical feeding situations to certify the assumptions and conclusions of this review.

Mitochondrial Dysfunction and Inflammaging in Heart Failure: Novel Roles of CYP-Derived Epoxylipids

Age-associated changes leading to a decline in cardiac structure and function contribute to the increased susceptibility and incidence of cardiovascular diseases (CVD) in elderly individuals. Indeed, age is considered a risk factor for heart failure and serves as an important predictor for poor prognosis in elderly individuals. Effects stemming from chronic, low-grade inflammation, inflammaging, are considered important determinants in cardiac health; however, our understanding of the mechanisms involved remains unresolved. A steady decline in mitochondrial function is recognized as an important biological consequence found in the aging heart which contributes to the development of heart failure. Dysfunctional mitochondria contribute to increased cellular stress and an innate immune response by activating the NLRP-3 inflammasomes, which have a role in inflammaging and age-related CVD pathogenesis. Emerging evidence suggests a protective role for CYP450 epoxygenase metabolites of N-3 and N-6 polyunsaturated fatty acids (PUFA), epoxylipids, which modulate various aspects of the immune system and protect mitochondria. In this article, we provide insight into the potential roles N-3 and N-6 PUFA have modulating mitochondria, inflammaging and heart failure.

Effects of Diets Enriched in Linseed and Fish Oil on the Expression Pattern of Toll-Like Receptors 4 and Proinflammatory Cytokines on Gonadal Axis and Reproductive Organs in Rabbit Buck

Infections of the genital tract can perturb the fertility in humans and animals. Pathogen recognition and activation of innate immunity onset through the pattern recognition receptor activation, such as Toll-like receptor 4 (TLR4), leading to the production of proinflammatory cytokines and mediators. TLR4 is expressed both on leukocytes and nonimmune cells. Rabbit TLR4 shows great similarity to its human counterpart. Moreover, the TLR4 signalling pathway could be modulated by long-chain polyunsaturated fatty acids (LC-PUFA). The objectives of this study were (i) to determine the expression levels of TLR4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit and (ii) to evaluate if the n-3 PUFA-enriched diets can modify their expression levels in the tissues and LC-PUFA profiles in seminal plasma. Fifteen rabbit bucks (n = 5/experimental group) were fed with different diets: commercial standard (group C), rich in extruded linseed (10%, group L), and in fish oil (3%, group FO) for 110 days. TLR4, TNF-α, and IL-1β mRNA were ubiquitously expressed throughout the hypothalamic-gonadal axis. However, TLR4 mRNA expression was lower in the hypothalamus than the epididymis (P < 0.01), seminal vesicles (P < 0.01), and pituitary gland (P < 0.05). Dietary enrichment in PUFA did not modify the gene expression profile nor the histological characteristics of the tissues. Conversely in seminal plasma, rabbits fed with L and FO had lower n-6 (P < 0.05), LC-PUFA n-6 (P < 0.05), and n-6/n-3 ratio (P < 0.05) but higher n-3 (P < 0.001) and LC-PUFA n-3 (P < 0.01) compared to the control group. Our study builds a map of the gene expression of TRL4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit, fundamental step for understanding the immune defence mechanisms. Diets enriched in LC-PUFA did not affect basal gene expression but modulated sperm fatty acid composition. Finally, rabbit may be an excellent animal model to study the relationship between inflammation and infertility, and the nutritional modulation of immune functions.

Dietary Cholesterol and Lipid Overload: Impact on Male Fertility

Lipid metabolic disorders due to poor eating habits are on the rise in both developed and developing countries, with a negative impact of the "Western diet" on sperm count and quality. Dietary lipid imbalance can involve cholesterol, fatty acids, or both, under different pathophysiological conditions grouped under the term dyslipidemia. The general feature of dyslipidemia is the development of systemic oxidative stress, a well-known deleterious factor for the quality of male gametes and associated with infertility. Sperm are particularly rich in polyunsaturated fatty acids (PUFA), an important characteristic associated with normal sperm physiology and reproductive outcomes, but also targets of choice for oxidative thrust. This review focuses on the effects of dietary cholesterol or different fatty acid overload on sperm composition and function in both animals and humans. The links between oxidative stress induced by dyslipidemia and sperm dysfunction are then discussed, including possible preventive or therapeutic strategies to preserve gamete quality, longevity when stored in cryobanking, and male fertility.