Optimizing dietary lipid use to improve essential fatty acid status and reproductive performance of the modern lactating sow:a review

Dietary lipid supplementation benefits the prolific and high-producing modern lactating sow. A comprehensive review of recent studies showed that lipid supplementation increases average daily energy intake, which is partitioned for lactation as indicated by greater milk fat output and improved litter growth rate. Recent compelling findings showed that addition of particular lipids during lactation improved the subsequent reproductive outcome of sows. Such benefits were related to the level of dietary essential fatty acids（EFA, linoleic acid, C18：2n-6; and α-linolenic acid, C18：3n-3） during lactation. Lactation diets without supplemental EFA resulted in a pronounced negative balance（intake minus milk output） of linoleic（-25.49 g/d） and α-linolenic acid（-2.75 g/d）; which compromised sow fertility（farrowing rate 〈 75 % and culling rates 〉 25 % of weaned sows）. This phenomenon seems to be increasingly important with advancing sow age because of a progressive reduction of body EFA pool over successive lactations. The net effect of supplemental EFA during lactation was to create a positive EFA balance, which improved the subsequent reproduction of sows. Adequate linoleic acid intake improved the proportion of sows that farrowed in the subsequent cycle（Farrowing rate（%） = [（-1.5 × 10^-3× linoleic acid intake（g/d）^2） ＋（0.53 × linoleic acid intake（g/d）） ＋（45.2）]; quadratic P = 0.002, R^2= 0.997, RMSE = 0.031）. In addition, increasing linoleic acid intake increased the number of pigs born in the subsequent cycle（total pigs born（n） = [（9.4 × 10^-5× linoleic acid intake（g/d）^2） ＋（0.04 × linoleic acid intake（g/d）） ＋（10.94）]; quadratic P = 0.002, R^2= 0.997, RMSE = 0.031）. Supplemental α-linolenic acid resulted in a rapid return to estrus（sows bred： sows weaned = 94.2 %; wean-to-estrus interval = 4.0 d） and achieved a high retention of pregnancy（sows pregnant： sows bred = 98 %）. Collectively, we conclude that a minimum dietary intake of10 g/d of α-linolenic acid, simultaneous with a minimum of 125 g/d of linoleic acid should be provided to ≥ 95 % of the sows; thereby, achieving a maximum sow reproductive efficiency through multiple mechanisms that include rapid return to estrus, high maintenance of pregnancy and large subsequent litter size in mature sows, that appear to be susceptible to EFA deficiency.

Development and Production of Omega-3 Fatty Acids-Enriched Foods is an Important Dietary Strategy to Improve People's Nutritional and Health Status

Both Omega-6 and Omega-3 fatty acids are essential nutrients important for cellular structure and function but cannot be synthesized by the human body and must be obtained from food.These two classes of fatty acids are metabolically and functionally different and antagonistically regulate many physiological and pathological processes.Thus,the relative balance between Omega-6 and Omega-3 fatty acids are critical for good health.However,today’s diet contains too much Omega-6 but too little Omega-3,leading to a severe imbalance with a very high Omega-6/Omega-3 ratio(>10)in most people.Many lines of evidence suggest that this imbalance is a key factor contributing to the development of modern chronic diseases.A growing number of studies ranging from laboratory research to clinical trials have shown that balancing the tissue ratio of Omega-6/Omega-3 fatty acids by increasing tissue levels of Omega-3 fatty acids and/or decreasing the content of Omega-6 fatty acids are very beneficial for the prevention and treatment of many life-threating chronic diseases as well as for health promotion of the general public.Therefore,development and production of foods rich in Omega-3-fatty acids should be considered as a key health program to balance essential fat intake and thereby improve the nutritional and health status of all people.

High Linoleic Acid in the Food Supply Worldwide-What are the Consequences?

The macronutrient composition of food supply in China has altered dramatically in the past 70 years.Fat(oil)has increased more than 4.2-times while the carbohydrate content has declined by 34%.Vegetable oils are the major component of the fat intake and since these oils are rich in linoleic acid,there has been a significant rise in the consumption of this fatty acid(as much as a 4-fold rise).Linoleic acid has essential functions in the body in skin and as a precursor of prostaglandins and related compounds.The current intakes of linoleic acid are well in excess of the minimum requirements.In this review,the effects of a food supply rich in linoleic acid on pain in arthritis and headache,non-alcoholic fatty liver and neural function are explored,with emphasis on lipid mediators derived from linoleic acid and other long chain polyunsaturated fatty acids.The current world food systems have created an imbalance of dietary linoleic acid in relation to n-3 polyunsaturated fatty acids,and an imbalance in the lipid mediators derived from these polyunsaturated fatty acids which may be contributing to sub-optimal health status.

Role of nutraceuticals during the transition period of dairy cows: a review

The transition period of dairy cattle is characterized by a number of metabolic, endocrine, physiologic, and immune adaptations, including the occurrence of negative energy balance, hypocalcemia, liver dysfunction, overt systemic inflammatory response, and oxidative stress status. The degree and length of time during which these systems remain out of balance could render cows more susceptible to disease, poor reproductive outcomes, and less efficient for milk production and quality. Studies on both monogastrics and ruminants have reported the health benefits of nutraceuticals(e.g. probiotics, prebiotics, dietary lipids, functional peptides, phytoextracts) beyond nutritional value, interacting at different levels of the animal's physiology. From a physiological standpoint, it seems unrealistic to disregard any systemic inflammatory processes. However, an alternate approach is to modulate the inflammatory process per se and to resolve the systemic response as quickly as possible.To this aim, a growing body of literature underscores the efficacy of nutraceuticals(active compounds) during the critical phase of the transition period. Supplementation of essential fatty acids throughout a 2-month period(i.e. a month before and a month after calving) successfully attenuates the inflammatory status with a quicker resolution of phenomenon. In this context, the inflammatory and immune response scenario has been recognized to be targeted by the beneficial effect of methyl donors, such as methionine and choline, directly and indirectly modulating such response with the increase of antioxidants GSH and taurine. Indirectly by the establishment of a healthy gastrointestinal tract, yeast and yeast-based products showed to modulate the immune response, mitigating negative effects associated with parturition stress and consequent disorders.The use of phytoproducts has garnered high interest because of their wide range of actions on multiple tissue targets encompassing a series of antimicrobial, antiviral, antioxidant, immune-stimulating, rumen fermentation, and microbial modulation effects. In this review, we provide perspectives on investigations of regulating the immune responses and metabolism using several nutraceuticals in the periparturient cow.

Comparison of fatty acid contents and composition in major lipid classes of larvae and adults of mosquitoes （Diptera： Culicidae） from a steppe region

Emerging aquatic insects, including mosquitoes, are known to transfer to terrestrial ecosystems specific essential biochemicals, such as polyunsaturated fatty acids （PUFA）. We studied fatty acid （FA） composition and contents of dominant mosquito populations （Diptera： Culicidae）, that is, Anopheles messeae, Ochlerotatus caspius, Oc. flavescens, Oc. euedes, Oc. subdiversus, Oc. cataphylla, and Aedes cinereus, inhabited a steppe wetland of a temperate climate zone to fill up the gap in their lipid knowledge. The polar lipid and triacylglycerol fractions of larvae and adults were compared. In most studied mosquito species, we first found and identified a number of short-chain PUFA, for example, prominent 14：2n-6 and 14：3n-3, which were not earlier documented in living organisms. These PUFA, although occurred in low levels in adult mosquitoes, can be potentially used as markers of mosquito biomass in terrestrial food webs. We hypothesize that these acids might be synthesized （or retroconverted） by the mosquitoes. Using FA trophic markers accumulated in triacylglycerols, trophic relations of the mosquitoes were accessed. The larval diet comprised green algae, cryptophytes, and dinoflagellates and provided the mosquitoes with essential n-3 PUFA, linolenic, and eicosapentaenoic acids. As a result, both larvae and adults of the studied mosquitoes had comparatively high content of the essential PUFA. Comparison of FA proportions in polar lipids versus storage lipids shown that during mosquito metamorphosis transfer of essential eicosapentaenoic and arachidonic acids from the reserve in storage lipids of larvae to functional polar lipids in adults occurred.

Nutrition and metabolism in poultry: role of lipids in early diet

Modern strains of broiler chickens are selected for fast growth and are marketed anywhere from 36 to 49 days after a21-day incubational period. For a viable healthy chick, all the necessary nutrients required for growth and development must be provided by the hen through the fertilized egg. The current feeding strategies for improved growth, health and productivity are targeted towards chicks after hatching. Considering the fact that developing chick embryo spends over 30 % of its total life span inside the hatching egg relying on nutrients deposited by the breeder hen, investigations on nutritional needs during pre-hatch period will improve embryonic health, hatchability and chick viability. In this context, investigations on hatching egg lipid quality is of utmost importance because, during incubation, egg fat is the major source of energy and sole source of essential omega-6（n-6） and omega-3（n-3） fatty acids to the chick embryo.Due to the unique roles of n-3 and n-6 fatty acids in growth, immune health, and development of central nervous system, this review will focus on the role of early exposure to essential fatty acids through maternal diet and hatching egg and its impact on progeny in meat-type broiler chickens.

Effect of the enrichment time with the tuna orbital oil emulsion on the fatty acids profile of juveniles of Artemia franciscana

Artemia is deficient in polyunsaturated fatty acids(PUFAs),particularly in arachidonic(ARA,20:4n-6),eicosapentaenoic(EPA,20:5n-3),and docosahexaenoic acid(DHA,22:6n-3).The aim of this study was to determine the optimal time in which the higher contents of PUFAs in juveniles of Artemia franciscana were obtained by the effect of enrichment with the tuna orbital oil emulsion.Six enrichment periods were evaluated:3,6,9,12,15 and 18 h,in addition to a control treatment(0 h).The most abundant fatty acids in A.franciscana were monounsaturated(43.10%±4.35–52.92%±5.82%),followed by saturated(33.83%±1.71–42.33%±2.31%)and PUFAs(8.86%±2.83%–21.32%±2.38%).ARA decreased over the enrichment time;the maximum content was 5.74±0.37%at 3 h,which was not statistically different with respect to the content recorded at 0 h.The highest content of EPA was at 3 h(6.47%±1.44%),without significant differences with the content registered at 0 h,while that from 6 h and until 15 h tended to decrease significantly.At 6 h,the content of DHA(8.84%±2.72%)was significantly higher compared to the rest of the treatments,which did not differ among themselves,or with the control.After to the 6 h and until 15 h,the content of PUFAs tended to decrease,which could indicate the metabolization of them by A.franciscana,coupled with the possible oxidation of these fatty acids in the enrichment solution.