Yolk free egg substitute improves the serum phospholipid profile of mice with metabolic syndrome based on lipidomic analysis

In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively investigated.Mice were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in serum.It was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein cholesterol.YFES exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened out.Carnitine C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to WE.YFES reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C levels.To sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism.

Variaiton in the composition of small molecule compounds in the egg yolks of Asian Short-toed Larks between early and late broods

The egg yolks of birds contain most of the maternally derived materials required for embryo development and are an important factor influencing embryo development and offspring viability.Individual variation in egg-laying date frequently occurs in passerines inhabiting highly seasonal environments.Females laying in early and late stages of the breeding season encounter different environment temperatures and food conditions,which can affect the levels of metabolities in their bodies,thereby altering the transmission of these materials to the eggs.We test a hypothesis that yolk small molecule compounds of Asian Short-toed Lark(Alaudala cheleensis)could vary between early(mid-May)and late(mid-June)broods.Using the UHPLC-MS/MS method,683 compounds belonging to 21 compound groups are detected in the yolks.The contents of 18 compounds are significantly different between early and late broods.Ten differential compounds are significantly higher in the early laid eggs,among whichγ-aminobutyric acid,creatine,prostaglandins,palmitoleic acid,linoleic acid,and trans linoleic acid are related to low environment temperature response.The eggs laid in late stage exhibit significantly higher levels of 5-L-glutamyl-L-alanine andγ-glutamate-leucine,1,3-dimethyluric acid and mannose,which may be attributed to females in the late group consuming more insects.We suggest conducting a comprehensive investigation to reveal the yolk small molecule compounds mediated maternal effects on offspring phenotypes under varying ecological conditions.

The Effect of Different Levels of Sesame Oil on Productive Performance, Egg Yolk and Blood Serum Lipid Profile in Laying Hens

Addition of sesame oil into layer diets has been proved to enrich the proportion of polyunsatu-rated fatty acids in animal’s products. In this study, the effects of different levels of sesame oil in the diets on the performance, egg yolk and blood serum lipid profile of Isa Brown laying hens were investigated. A total of 96 layers were assigned into 4 groups to receive either 1 of 4 different diets contained 0.0%, 1.5%, 3.0% and 4.5% sesame oil, respectively. Sample of 12 eggs obtained from each groups were assessed for egg quality. The egg yolk fatty acid profile was determined with gas chromatography. Results revealed that the higher levels of sesame oil in the diet decreased egg production, egg weight, and egg yolk color except feed conversion ratio. In addition, supplementation of sesame oil increased the flow index of the eggs and the Haugh unite. The egg yolk lipid profile was not significantly different in the sesame oil fed groups, whereas, compare to control, it decreased the level of cholesterol. The blood serum lipid profile decreased in the sesame oil groups compare to control group. Meanwhile, monoacildigliserol also decreased in the sesame addition groups. In parallel with increasing levels of sesame oil, monounsaturated fatty acid (oleic acid) in the egg yolks significantly increased compared to the control (37.00%, 42.89%, 42.20% and 43.48%, respectively). It can be implied that sesame oil supplementation into the laying hens diet is necessary to produce monounsaturated fatty acid (MUFA) enriched eggs.

Comprehensive lipidomics and volatile compounds profiling reveals correlation of lipids and flavors in DHA-enriched egg yolk

DHA-enriched eggs have gained popularity due to their unique nutritional value,but their flavor can be challenging for some consumers to accept.The study analyzed the correlation of lipids and flavors in DHA-enriched egg yolks using comprehensive lipidomics and volatile compound analysis.The results showed that 411 lipids were detected in two egg yolk samples.Among them,148 lipid species,including 48 DHA-containing lipids,were significantly higher in DHA-enriched egg yolks than in Common ones(P<0.05).Furthermore,of the 24 volatile compounds detected,the contents of benzaldehyde,heptanal,hexanal,decanal and 2-nonanone in DHA-enriched egg yolks were significantly higher than in Common egg yolks(P<0.05).The“fishy”smell characteristic of DHAenriched egg yolks was mainly caused by volatile aldehydes,which may be produced through the hydrolysis of lipids in the egg yolk to free fatty acids and further oxidation.Analysis of the correlation network diagram revealed that phospholipids containing docosahexaenoic acid(DHA),linoleic acid,or oleic acid chains were the main contributors to the characteristic flavor of DHA-enriched egg yolks.Overall,this study explored the effect of different lipids on the flavor of DHA-enriched egg yolks and provided a theoretical basis for the production and improvement of DHA-enriched eggs.

Chicken egg yolk antibodies (IgY) as non-antibiotic production enhancers for use in swine production： a review

In recent years, the use of in-feed antibiotics for growth and disease prevention in livestock production has been under severe scrutiny. The use and misuse of in-feed antibiotics has led to problems with drug residues in animal products and increased bacterial resistance. Chicken egg yolk antibodies （IgY） have attracted considerable attention as an alternative to antibiotics to maintain swine health and performance. Oral administration of IgY possesses many advantages over mammalian IgG such as cost-effectiveness, convenience and high yield. This review presents an overview of the potential to use IgY immunotherapy for the prevention and treatment of swine diarrhea diseases and speculates on the future of IgY technology. Included are a review of the potential applications of IgY in the control of enteric infections of either bacterial or viral origin such as enterotoxigenic Escherichia coil, Salmonella spp., rotavirus, porcine transmissible gastroenteritis virus, and porcine epidemic diarrhea virus. Some potential obstacles to the adoption of IgY technology are also discussed.

The role of low-density lipoprotein （LDL） and high-density lipoprotein （HDL） in comparison with whole egg yolk for sperm cryopreservation in rhesus monkeys

Low-density lipoprotein （LDL） extracted from hen egg yolk has recently been considered to be superior to whole egg yolk in sperm cryopreservation of various animal species. Meanwhile, there was a notion that high-density lipoprotein （HDL） in egg yolk may have a negative effect on post-thaw survival. The role of LDL and HDL in sperm cryopreservation of rhesus monkeys has not been explored. The present study evaluates their effect in comparison with egg yolk with or without the addition of permeable cryoprotectant （glycerol） on sperm cryopreservation of rhesus macaques. In addition, various additives intended to change the lipid composition of LDL-sperm membrane complex have also been tested for their effectiveness in preserving post-thaw viability. Our findings indicated that LDL is the main component in egg yolk that is responsible for its protective role for sperm cryopreservation in rhesus monkeys. Regardless of the presence or absence of glycerol, the protective role of LDL is similar to that of egg yolk and we did not observe any superiority in post-thaw survival with LDL when compared to egg yolk. Modifying the lipid composition of LDL-sperm membrane complex with the addition of cholesterol, cholesterol loaded cyclodextrin and phosphatidylcholine also did not yield any improvements in pest-thaw survival; while addition of methyl-β-cyclodextrin reduced post-thaw motility. HDL plays a neutral role in sperm cryopreservation of rhesus monkeys. The present study suggests that egg yolk may still hold advantages when compared with LDL as effective components in extenders for sperm cryopreservation in rhesus monkeys.

Protection of Carassius auratus Gibelio against infection by Aeromonas hydrophila using specific immunoglobulins from hen egg yolk

Specific immunoglobulin (IgY) from egg yolk against Aeromonas hydrophila was produced by immunization of White Leghorn hens with formalin-killed whole cells of A. hydrophila. ELISA test using A. hydrophila as the coating antigen revealed that the specific antibody titer started to increase in the egg yolk at the 13th day post-immunization (P/N=2.18), reached the peak at the 56th day (P/N=13.82), and remained at high level until day 133 (P/N=7.03). The antibody was purified by saturated ammonium sulphate with a recovery rate of 63.5%. The specific IgY inhibited the growth of A. hydrophila at a concentration of 1.0 mg/ml during the 18 h incubation. Pre-treatment of polyploid gibel carps Carassius auratus Gibelio with specific IgY had a protection rate of 60% (6/10) against challenge with A. hydrophila, while none of the fishes in the control groups receiving sterile phosphate buffered saline (PBS) or non-specific IgY survived the challenge. Treatment of fishes with the specific IgY 4 h after the challenge also had lower mortality (70%, 7/10), a 30% reduction against the control PBS or non-specific IgY groups (10/10). These results indicate that specific IgY antibodies could be obtained easily from hens immunized with an inactivated A. hydrophila and could provide a novel alternative approach to control of diseases in fishes caused by this organism.

Effect of leaf essential oil of Coccinia indica on egg hatchability and different larval instars of malarial mosquito Anopheles stephensi

Objective:To assess the larvicidal and egg hatching inhibition property of the leaf essential oil of Cocrinia indica（C.indica） against Anopheles stephensi（An.stephensi）.Methods:The larvicidal potential of C.indica leaf essential oil was evaluated against 1st.2nd.3rd and 4th instars larvae of An.stephensi using WHO protocol.The 24h LC50and LC90 values of the essential oil were determined following probit analysis.The egg hatching inhibition activity was also tested at 10.20.40.and 60 mg/L The IC50 value of essential oil was determined against eggs of An. stephensi.Results:The essential oil extracted from C.indica possessed excellent larvicidal and egg hatching inhibition activity against An.stephensi.The bioassays showed LC50—LC90of 54.3- 140.3.65.5-155.6,86.8-180.7 and 95.3-192.6 for 1 st.2nd.3rd.and 4th larval insiars.respectively. The 5095 egg hatching inhibition concentration(IC50) was noted at 16.5 mg/L.Conclusions:The present finding suggest that the C.indica leaf essential oil provided an excellent potential for controlling An.slephemi mosquito at earlier stage of their life cycle.

Isolation of egg yolk IgY from hens immunized with S.mutans B29-33 and S.sobrinus 6715

目的 :从鸡蛋中提取特异性抗体 ,鉴定抗体性质并分析其蛋白质含量 ,以探索一种制备被动免疫防龋抗体的制备方法。方法 :变形链球菌GTF高表达株S .mutansB2 9- 33及茸毛链球菌S .sobrinus 6 715免疫母鸡 ,采用硫酸铵沉淀法提取鸡蛋黄抗体 ,SDS -PAGE凝胶扫描鉴定抗体性质 ,分析其纯度并用分光光度法测蛋白质含量。结果 :用硫酸铵沉淀法可提取出鸡蛋黄抗体 ,其性质为IgG ,蛋白质含量约为 7.0 0mg/ml。结论 :鸡蛋黄抗体含量高 ,作为被动免疫抗体的载体有较好的应用前景。

HPLC Analysis of Egg Yolk Phosphatidylcholine by Evaporative Light Scattering Detector

Egg yolk phosphatidylcholine(EYPC) is being widely used in food and pharmaceutical industries nowadays owing to its surface activity,pharmaceutical usefulness,and so on.Common determination methods of phospholipids were based on the American Oil Chemists' Society(AOCS) Official Method Ja7b-91,in which n-hexane/2-propanol/acetate buffer was used as the mobile phase.In order to achieve desired results,gradient elu-tion or buffer solution was used,which made the detection process more complicated.Moreover,water or buffer solution could affect the silica gel column both on its lifespan and the separation efficiency significantly.In this study,different mobile phase and detector were used to simplify EYPC analyzing process instead of using water within the mobile phase.The optimized HPLC operating conditions are as follows:pure methanol as a mobile phase,flow rate of 1.0 ml·min-1,silica gel column(250 mm×4.6 mm,5 μm,Inertsil GLTM),column temperature 30 ℃ and low temperature evaporative light scattering detector(40 ℃,0.35 MPa) as used.Under this optimal condition,the linear relative coefficient of the standard curve is 0.998 and the recovery was in the range of 96.83%-101.58% with a relative standard deviation of 1.79%(n=6).

Influence of Dietary Isoflavonoids on Stability of Egg Yolk Lipids

An experiment was conducted to investigate the influence of dietary tea polyphenol (TP) and daidzein (DA) on lipid stability of egg yolk. Two-hundred and seventy 27-week-old Hisex Brown laying hens were divided into nine groups, fed a diet supplemented with 0, 5, 10, 20, 40 mg kg-1 TP and 5, 10, 20, 40 mg kg-1 DA respectively for a period of 8 weeks ad libitum. The dietary addition of TP and DA both could reduce egg yolk LPO content significantly at the end of 4-week experiment (P < 0.05) and keep egg yolk lipid stable at the supplemental dose of 10 mg kg-1 diet respectively. A significant liner reduction in egg yolk LPO content was found with the increasing of dietary TP and DA. The egg yolk LPO content was decreased by 23.1 and 27.0% (P< 0.05) with the supplementation of TP and DA respectively at 40 mg kg-1 diet. The LPO contents in liver, plasma and egg yolk were decreased significantly with the dietary addition of TP or DA respectively (P < 0.05). There was no significant difference between the effects of TP and DA on improvement of layers' antioxidative capacity. The dietary TP and DA both could improve the bird's antioxidative level directly irrelevant to SOD and GSH-Px activities.

A Combination of Wheat Bran and Vegetable Oils as Feedstuff in Laying Hens’Diet:Impact on Egg Quality Parameters

Wheat bran (WB) is an important side product of the milling industry and plays an increasing role in animal feeding. Despite its nutritional value, its application is limited as a result of its pronounced fiber content. Taking into account the potential use of WB supplementation in feed for laying hens thereby replacing human edible foodstuffs, the influence of different WB levels (0 g·kg-1, 75 g·kg-1, and 150 g·kg-1) combined with sunflower or rapeseed oil on egg quality was studied. Among the egg-related quality parameters investigated, eggshell cleanliness, shell rigidity, egg weight, haugh units, yolk and albumen mass, color, pH value, dry matter, crude protein, crude ash, fatty acid spectrum, cholesterol and α-tocopherol of the yolk were monitored. No negative effect of WB supplementation was observed in terms of egg weight, shell weight, albumen weight, yolk weight, haugh unit, shell thickness and eggshell breaking strength. However, certain parameters (i.e. α-tocopherol content, Σn-3 PUFA) were enhanced by feeding 75 g·kg-1 and 150 g·kg-1 WB. The use of WB (75 g·kg-1 and 150 g·kg-1) had no negative effect on egg quality and can, therefore, be recommended for laying hen diets up to 150 g·kg-1. Additionally, the application of rapeseed oil high in Σn-3 PUFA resulted in yolks exhibiting a low Σn-6 PUFA/Σn-3 PUFA ratio.

Correlation Between Cholesterol Content in Egg Yolks and Laying Rate

[Objectives]This study was conducted to investigate the relationship between cholesterol content in egg yolks and laying rate of laying hens.[Methods]Forty eight 450-day-old Hyline brown hens with uniform weight were randomly divided into 4 groups with 3 replicates in each group and 4 individuals in each replicate.Group 1 as the control check group(CK)was fed the basal diet;group 2 was fed the basal diet with the addition of 150 g/t of probiotics;group 3 was the basal diet+200 g/t lipase group;and group 4 was fed the basal diet with the addition of 150 g/t of probiotics and 200 g/t of lipase.The preliminary trial period was 10 d,and the experimental period was 30 d.[Results]The cholesterol content in the egg yolks of each test group was higher than that of the control group at 14 and 28 d after the drug administration.The laying rate of each test group began to increase at 14 d after the drug administration;and the laying rate of each test group increased significantly 28 d after the drug administration.It indicated that with the increase of cholesterol in egg yolks,the laying rate of laying hens increased significantly.[Conclusions]This study provides a certain experimental basis for culture production of laying hens.

Effect of Time and Fatty Acid Composition in Eggs of White Leghorn Hens Supplemented with Tuna Oil

The study evaluated the effect of time and fatty acid (FA) composition in eggs of laying hens supplemented with tuna oil (TO). Two hundred White Leghorn hens 30-week were divided into 5 treatments with 4 replicates of 10 birds each. Treatments were assigned randomly and consisted of 0%, 0.75%, 1.50%, 2.25% and 3% TO in commercial sorghum-soybean meal diets, in which the soybean oil was partially replaced. The experiment was conducted for 90 days. At days 28, 56 and 84 of the experiment, 10 eggs per replicate were collected for chemical analysis. Feed intake, egg production rate, egg weight, and feed conversion were not influenced by dietary treatment. FA content was significantly altered (P < 0.05) by TO, showing a progressive increase in egg n-3 FA (especially docosahexaenoic [DHA] and eicosapentaenoic [EPA] acids) when TO was added. Levels of EPA and DHA were higher (P < 0.05) in the egg lipids of TO fed hens than those in the control group. This was correlated (P < 0.05) with the concentration of TO in the diet. However, no significant differences were observed either in egg weight or percent of egg lay between groups. There was a high correlation (P < 0.05) between TO inclusion level in the diet and the incorporation of EPA (r = 0.96) or DHA (r = 0.92) into the egg yolk and an overall decrease in n-6 FA. There was a high correlation (P < 0.05) between TO inclusion level and the incorporation of linoleic acid (LA, r = -0.95) or arachidonic acid (AA, r = -0.96) into the egg yolk. The highest incorporation (P < 0.05) of total n-3 FA content in eggs was obtained with 3% TO/kg. This increase was proportional to TO inclusion levels in the diets (r = 0.95). The results indicate that the n-3 FA content in eggs can be increased by dietary supplementation with TO, and that TO can serve as a reasonable alternative feed ingredient in layer diets to produce a healthier choice of egg.

Antibodies to Newcastle Disease Virus in Egg Yolks of Great Cormorant (<i>Phalacrocorax carbo</i>) at Qinghai Lake

Newcastle disease virus (NDV) is not considered as cause of serious disease in humans. But, recent data make it clear that, under particular circumstances, it is indeed possible for NDV to cause severe human respiratory disease. Newcastle Disease infection has been reported in many bird species. Cormorants that inhabit at the Qinghai-Tibet Plateau are mainly represented by Great Cormorant (Phalacrocorax carbo sinensis), which is distributed mainly on the Qinghai Lake area. Cormorants are considered as one of the main NDV-reservoir. We conducted the study for the presence of antibodies to Newcastle disease virus by hemagglutination inhibition test in yolks. We got 50% of seropositive yolks to Newcastle disease virus. These results show that NDV circulates in the Qinghai Lake population of cormorants. We first used the technique of detection of antibodies to Newcastle disease virus in the egg yolk for study the circulation of the virus in cormorants and demonstrated its effectiveness. We should carefully monitor cases of pneumonia in the population of people living around the lake and assess the causes of the disease.

The Effect of Feeding Laying Hen Conventional and Omega-3 Enriched Diet on Fatty Acid Profiles in Egg Yolk Lipids

The aim of this research was to enrich table eggs with n-3 polyunsaturated fatty acids （n-3 PUFA）, especially with essential eicosapentaenoic acid （EPA） and docosahexaenoic acid （DHA）. After five weeks of feeding of laying hens with standard and experimental diets, there was analysis carried out to determine the fatty acid profile in egg yolks of both groups. Omega-3 eggs contain statistically significantly （P 〈 0.05） less sum of saturated fatty acids （∑SFA） and more∑n-3 PUFA, as well as narrower ratio of∑n-6/∑n-3 PUFA than conventional eggs. If referring to individual fatty acids of omega-3 eggs, there were increased portions （P 〈 0.05） of α-linolenic acid （α-LNA）, docosapentaenoic acid （DPA）, EPA and DHA determined in this research, which was in line with the research objective. Within the presented research, concentration of n-3 PUFA in egg yolk lipids of experimental group was two times higher than that in the control group. The ratio of ∑n-6 PUFA/∑n-3 PUFA was reduced from 12.04 to 6.17. Within their enzymatic system, laying hens can act as a bioreactor to naturally enrich their eggs with n-3 PUFA, especially with EPA and DHA. The results of this research proved that the fatty acid profile can be modified by designing of laying hens＇ diets with specific forages. Eggs were enriched with favorable fatty acids in the following order： α-LNA 〉 DHA 〉 DPA 〉 EPA.

BIOCHEMICAL CHANGES DURING DEVELOPMENT OF EGGS AND YOLK-SAC LARVAE OF HERRING AND PLAICE

Changes in quantities of water, sodium, potassium, lipid and protein were compared in developing eggs and yolk-sac larvae of herring dupes harengus L., a species with demersal eggs, and plaice Pleuroncctcs platessa L., a species with pelagic eggs. The principal difference between the two species was the occurrence in herring, but not in plaice of considerable increases in water content and in one or both of the above ions at three distinct stages: at fertilization,during the middle stage of egg development, and in the days immediately after hatching. Newly hatched larvae of the two species differed greatly in water content because of the difference in mass and water content of the yolk, not in the water content of the rest of the body. In herring, there were increases in sodium and potassium which coincided broadly with the increase in water content. These differences are related to the gradual acquisition of buoyancy by herring during this period, comparable with the buoyancy conferred on plaice eggs

Investigation of Two Precipitation Methods for Extracting Immunoglobulin Y(IgY)from Egg Yolks

Two groups of hens(control and immunization group)were arranged in an experimental design with an immunization schedule of 3 injections of BSA antigen.IgY antibodies were extracted from egg yolks by two precipitation processes(chloroform and polyethylene glycol precipitates)and quantified using a standard curve of protein concentration.The purification of IgY was confirmed by SDS-PAGE.Total protein extracted from egg yoks were less contaminated with yellow pigments(lutein and zeaxanthin)nd by using chloroform precipitate.The 2 week post-immunization,IgY-1 concentration increased respectively to 3903±726μg.ml(chloroform-1 extraction process)and 2937±294μg.ml(PEG extraction process)(P<rd 0.01).After 3 immunization,IgY level obtaining from in immunization group extracted by chloroform process(6633±1166μg.ml-1)increased 2.7 times higher than that in control group(2482±414μg.ml-1).Whereas IgY concentrations obtained from PEG extraction process were not significantly different between the experimental group and control group.Chloroform and PEG precipitation methods had the same protein profile on the SDS-PAGE.IgY antibody was identified by the presence of bands corresponding with IgY heavy chain(67-70 kDa)and IgY light chain(25 kDa)for both precipitation processes.

A rapid and convenient dot-immunobinding assay for chicken egg-yolk antibodies

The dot-immunobinding assay was applied to investigate the characteristics of chicken egg yolk antibodies. This method of assay was proved to be a rapid and simple method to demonstrate and characterize the egg-yolk antibody IgY in comparison with the traditional ELISA assay. By using the BandScan software, the gray scale value of dots and the background could be determined. According to the intensity of dots (gray scale value) compared to the standard sample of 10μg, how much IgY remained can be determined in a shorter time.

咸鸭蛋黄品质劣化分析与调控技术的研究进展

鸭蛋经食盐腌制加工成的咸蛋,是我国传统蛋制品之一,蛋黄质量好坏常被用来评价咸蛋的品质。鸭蛋盐渍过程中蛋黄黑化和泥化是影响咸蛋品质的劣化现象,该研究从蛋黄颜色劣变造成的蛋黄黑化现象和质地过度软化劣变造成的蛋黄泥化现象两个方面介绍了蛋品加工过程中品质劣变的表征及影响因素,重点综述了类似的蛋、肉、蔬菜等食品硫化致黑和氧化致软两种品质劣变的机制和控制技术及其效果。为鸭蛋加工的标准化、工业化以及安全化生产咸蛋提供理论支持。