Egg Ingestion Research Articles

Industry Funding and Cholesterol Research: A Systematic Review.

The effect of diet on blood cholesterol concentrations has become controversial. We assessed whether industry-funded studies were more likely than non-industry-funded studies to report conclusions that were not supported by their objective findings. PubMed and Cochrane Central Register of Controlled Trials searches through March 8, 2019, yielded 211 relevant articles. The percentage of industry-funded studies increased from 0% in the 1950s to 60% for 2010 tp 2019 (P < .001). Of 94 non-industry-funded intervention studies for which the effect of egg ingestion on cholesterol concentrations could be determined, net cholesterol increases were reported in 88 (93%) studies (51% statistically significant, 21% not significant, 21% significance not reported). Among 59 industry-funded intervention studies, net cholesterol increases were reported in 51 (86%) studies (34% statistically significant, 39% not significant, and 14% significance not reported). No studies reported significant cholesterol decreases. Nonsignificant net cholesterol decreases were reported by 6 (6%) non-industry-funded and 8 (14%) industry-funded studies. However, 49% of industry-funded intervention studies reported conclusions that were discordant with study results (ie, net cholesterol increases were described as favorable in the articles' stated conclusions), compared with 13% of non-industry-funded studies. Readers, editors, and the public should remain alert to funding sources in interpreting study findings and conclusions.

Awareness of vitamin B7: A growing problem in clinical practice

Biotin (vitamin B7, hexahydro-2-oxo-1H-thieno[3,4-d]imidazole-4-pentanoic acid) is not synthesized by mammals: dietary sources include plant based foods, yeast, liver, kidneys, heart, pancreas, egg yolk, poultry, and cow’s milk. Synthesis via the gut bacteria may also play a role. Recommended daily allowances are based on normal intake; EU RDA is 50 μg/day, the US adequate intake (AI) for adults is 30 μg/day.Biotin is required for the function of four carboxylases: pyruvate carboxylase, propionyl CoA carboxylase, multiple CoA carboxylase, and acetylCoA carboxylase I and II. Holocarboxylase synthase is required to attach biotin to their active sites. Biotin also modulates the expression of up to 2000 genes, and has effects on immune function, largely through biotinylation of histones and other proteins.Biotinidase, the enzyme which splits biotin from biotinyl lysine (biocytin), and from peptides containing biocytin, recycles biotin from endogenous turnover and facilitates absorption from exogenous sources, together with the sodium-dependent multivitamin transporter.Nutritional deficiency of biotin is rare and most cases relate to inborn errors of biotin metabolism and transport, long-term use of parenteral nutrition, chronic anticonvulsant therapy, or avidin binding of dietary biotin due to excessive ingestion of egg whites.Excessive ingestion of biotin from supplements is increasingly common. Biotin has no direct toxicity, but high circulating levels can interfere with many commercially available immunoassays which use the interaction between biotin and streptavidin. This can result in a spurious but plausible biochemical picture of disease supported by two or more independent immunoassay based tests.The laboratory detection of functional biotin deficiency relies upon detection of multiple carboxylase deficiency, identified and followed by measurement of urinary 3-hydroxyisovaleric acid (3HIVA, ideally using isotope dilution GC-MS, or isotope dilution-LC-MSMS (ID-LC-MSMS)) or plasma 3-hydroxyisovaleryl carnitine (3HIVc, measured using ID-LC-MSMS). These methods are reviewed, together with methods for assessing biotinidase activity.This chapter also describes methods for the direct measurement of biotin in foods, blood, serum/plasma, and urine. These relied for many years on microbiological assays. These were followed by binding assays using avidin with radioactive biotin or enzyme linked biotin as tracers, with or without chromatographic separation to distinguish between biotin, metabolites of biotin, and biotinylated peptides. Latterly, the introduction of specific assays using ID-LC-MSMS should allow traceable and harmonized assay of plasma/serum biotin. These could be particularly helpful to detect excessive ingestion of biotin supplements.We conclude that there is a need for laboratory methods with adequate sensitivity and specificity to reliably diagnose biotin deficiency and monitor biotin levels in patients receiving supplements. There are a limited number of reliable markers of biotin status and no single marker can reliably distinguish moderately deficient biotin from sufficient and supplemented. Measurement of 3HIVA and 3HIVc, the functional markers of biotin status, is currently the recommended approach.

A 5-year Summary of Real-life Dietary Egg Consumption after Completion of a 4-year Egg OIT Protocol

Long-term dietary implications of egg OIT (eOIT), including desensitization and sustained unresponsiveness (SU), are not well described. Previously described egg allergic subjects (5-11 yo) were randomized to eOIT (n=40, treated with eOIT up to 4 years) or placebo (n=15, 1 year). Subjects passing a 10g OFC on therapy were considered desensitized and underwent a 10g OFC and open feeding 4-6 weeks after discontinuing therapy to determine SU. Long-term follow-up questionnaires (LFQ) assessing egg consumption and symptoms were administered annually for 5 years following trial completion. At study completion, 20/40 (50%) eOIT subjects were classified as SU, 11/40 (28%) subjects desensitized, and 9/40 (22%) not desensitized. Annual LFQ completion ranged from 76-82% of all subjects (85-95% of the SU group). At year 5, 93% (30/32) of eOIT subjects were ingesting some egg compared to 64% (7/11) of placebo (p=0.029). 100% (19/19) of SU subjects were ingesting both concentrated and baked egg versus 43%, 17%, and 36% in the desensitized, not desensitized, and placebo groups, respectively. Decreased frequency and amount of egg ingestion and increased symptoms were observed in all non-SU groups versus the SU group. Epinephrine was required after concentrated egg ingestion in 3 non-SU subjects. Five years after study completion, eOIT treated subjects achieving SU were highly likely to consume and tolerate dietary egg, while other groups had more variable egg consumption and increased symptoms associated with consumption. Further study to develop biomarkers predictive of treatment response is necessary to mitigate risk and assess clinical outcomes with OIT.

Occurrence and Quantitative Risk Assessment of Twelve Mycotoxins in Eggs and Chicken Tissues in China.

Aflatoxins (AFs), deoxynivalenols (DONs), and zearalenones (ZENs) are common mycotoxins that contaminate feedstuff, causing contamination of poultry products. In our study, these mycotoxins were quantified in 152 egg samples collected from markets in Jiangsu (JS), Zhejiang (ZJ), and Shanghai (SH) and in 70 chicken tissue samples (liver, heart, and gizzard) from ZJ in China. The main mycotoxins observed in egg samples were DON, 15-AcDON, and ZEN, although only ZEN family mycotoxins (ZEN, α-ZEL, β-ZEL, and α-ZAL) were detected in chicken tissues. Furthermore, for the first time, we assessed the health risks of exposure of three populations (children, adults, and elder adults) to DONs (DON, 3-AcDON, and 15-AcDON) and ZEN in eggs (from three different areas) and to ZEN in chicken tissues. We show that the mean dietary intake (DI) values and the 97.5th percentile DI values of DON and ZEN through egg ingestion were lower than the provisional maximum tolerable daily intake (PMTDI) (1 μg/kg body weight (BW)/day) for the three populations in the three geographical areas studied. However, eggs contaminated with high levels of DONs and ZEN contributed to a large proportion of the PMTDI of these mycotoxins, especially in children and elder adults. Although ZEN was highly detected in the chicken tissues, no significant health risk was observed.

ACQUIRED HYPERSENSITIVITY TO EGG FOLLOWING AUTOLOGOUS STEM CELL TRANSPLANTATION

Introduction Transplant-acquired food allergy (TAA) is the presence of a food allergy (FA) after transplantation of bone marrow or a solid organ. TAA has a prevalence of 6-57%, and more common in children. The most common foods are milk, egg and peanut. It can present up to 1 year after the transplant and is mostly transitory. Case Description An 11-year-old female with diagnosis of type 1 diabetes mellitus in December 2017, received an autologous stem cell transplant on March 2018 and chemotherapy with mesna and fludarabine. Three weeks after transplantation presents gastrointestinal symptoms associated with egg ingestion, characterized by nausea, vomiting, abdominal pain and distension, accompanied by eosinophilia in blood count 4.42 × 103, 49.7% as well as IgE 60.4 IU / ml. Skin prick tests for food were performed with positive result to egg (albumen). Treatment is started with elimination diet. Discussion This is the second reported case of TAA in a patient with TACH. Post-transplant patients may present atopic diseases associated with immunosuppressive drugs, type of transplanted tissue and a history of atopy. FA can manifest as Eosinophilic Gastrointestinal Disease (vomiting, diarrhea and abdominal pain), eosinophilia> 1000 cel / dl, specific IgE. Mechanisms of TAA after TACH include the transfer of specific allergen and T cells. TAA is an uncommon condition, but must be taken into account in post-transplant patients. The treatment is based on the diet of strict elimination of the food, education and plan of anaphylaxis with epinephrine. For the most part, cases are transitory and require subsequent reassessment.

NON-TRANSFERENCE OF FOOD ALLERGY AND FOOD PROTEIN-INDUCED ENTEROCOLITIS SYNDROME (FPIES) AFTER BONE MARROW TRANSPLANT

Introduction Transfer of food allergy after bone marrow and solid organ transplant are well described in literature. Here we report a case of non-transference of IgE mediated food allergy (peanut) and Food Protein-Induced Enterocolitis Syndrome (FPIES) (egg) following related donor bone marrow transplant. Case Description The donor is a 3 year-old female who initially presented with typical symptoms of egg related FPIES at 9 months of age. Subsequently was found to be sensitized to peanut (IgE 0.34 kUA/L). She initially passed peanut challenge, but peanut was never introduced. She lost tolerance and developed IgE mediated allergy to peanuts. Peanut allergy was confirmed upon challenge at 2 years of age. She has since avoided peanuts. She continues to have FPIES to egg. Her most recent FPIES reaction following accidental ingestion of egg and requiring fluid resuscitation was at 2 years of age. During this time, she served as a related bone marrow donor for her sibling. Even after withdrawal of the majority of immunosuppression and immune reconstitution with the donor bone marrow the sibling continues to tolerate both egg and peanut. Discussion Though transfer of food allergy has been reported following bone marrow transplant. This is the first case where transfer of FPIES has been a concern. This case is also unique because both FPIES and anaphylactic food allergy co-existed in the donor. Allergy in the donor was documented before and after transplant and likewise tolerance was documented in the recipient pre and post-transplant.

The health and economic outcomes of early egg introduction strategies.

Studies suggest early egg introduction (EEI) in the first year of life is associated with reduced risk of developing egg allergy. No US recommendations exist regarding optimally implementing EEI. Using simulation and Markov modelling over a 20-year horizon, we explored optimal EEI strategies applied to US, European and Canadian populations, comparing screening of high-risk infants (skin prick testing [SPT] or serum-specific IgE[sIgE]) before introducing cooked egg at 6months of life vs egg introduction at home, without screening, for all infants. A no-screen approach dominated egg SPT screening of high-risk infants with early-onset eczema. Base model per-patient incremental costs of SPT were $6865 US dollars (USD), 6801 euros and $10610 Canadian dollars (CAD). For egg sIgE screening in primary care settings, base model incremental costs were $16722 USD, 18072 euros and $28193 CAD. As the simulation concluded 2.5% were egg allergic without screening vs 9.5%, 12% and 21.4% of children undergoing SPT, delayed introduction or sIgE screening. Incremental societal costs from screening reached $2009351175 USD for SPT and $4894445790 USD for sIgE testing. In sensitivity analyses, if the risk of reaction with initial egg ingestion was ≥22.5%, SPT before EEI became a preferred strategy. A no-screen approach dominated both EEI of raw pasteurized egg and delayed cooked egg introduction approaches. Assuming initial reaction rates<22.5%, a no-screening EEI cooked egg approach has superior health and economic benefits in terms of number of egg allergy cases prevented and total healthcare costs vs screening testing.

Cooking influence in tolerance acquisition in egg-induced acute food protein enterocolitis syndrome

BackgroundFew studies on the age of resolution of Food Protein Induced Enterocolitis Syndrome (FPIES) induced by solid foods are available. In particular, for FPIES induced by egg, the mean age of tolerance acquisition reported in the literature ranges from 42 to 63 months. ObjectiveWe have assessed whether the age of tolerance acquisition in acute egg FPIES varies depending on whether the egg is cooked or raw. MethodsWe conducted a retrospective and multicentric study of children with diagnosis of acute egg FPIES seen in 10 Italian allergy units between July 2003 and October 2017. The collected data regarded sex, presence of other allergic diseases, age of onset of symptoms, kind and severity of symptoms, cooking technique of the ingested egg, outcome of the allergy test, age of tolerance acquisition. ResultsSixty-one children with acute egg FPIES were enrolled, 34 (56%) males and 27 (44%) females. Tolerance to cooked egg has been demonstrated by 47/61 (77%) children at a mean age of 30.2 months. For 32 of them, tolerance to raw egg has been demonstrated at a mean age of 43.9 months. No episodes of severe adverse reaction after baked egg ingestion have been recorded. ConclusionsIt is possible to perform an OFC with baked egg, to verify the possible acquisition of tolerance, at about 30 months of life in children with acute egg FPIES.

Whole egg, but not egg white, ingestion induces mTOR colocalization with the lysosome after resistance exercise.

We have recently demonstrated that whole egg ingestion induces a greater muscle protein synthetic (MPS) response when compared with isonitrogenous egg white ingestion after resistance exercise in young men. Our aim was to determine whether whole egg or egg white ingestion differentially influenced colocalization of key regulators of mechanistic target of rapamycin complex 1 (mTORC1) as means to explain our previously observed divergent postexercise MPS response. In crossover trials, 10 healthy resistance-trained men (21 ± 1 yr; 88 ± 3 kg; body fat: 16 ± 1%; means ± SE) completed lower body resistance exercise before ingesting whole eggs (18 g protein, 17 g fat) or egg whites (18 g protein, 0 g fat). Muscle biopsies were obtained before exercise and at 120 and 300 min after egg ingestion to assess, by immunofluorescence, protein colocalization of key anabolic signaling molecules. After resistance exercise, tuberous sclerosis 2-Ras homolog enriched in brain (Rheb) colocalization decreased ( P < 0.01) at 120 and 300 min after whole egg and egg white ingestion with concomitant increases ( P < 0.01) in mTOR-Rheb colocalization. After resistance exercise, mTOR-lysosome-associated membrane protein 2 (LAMP2) colocalization significantly increased at 120 and 300 min only after whole egg ingestion ( P < 0.01), and mTOR-LAMP2 colocalization correlated with rates of MPS at rest and after exercise ( r = 0.40, P < 0.05). We demonstrated that the greater postexercise MPS response with whole egg ingestion is related in part to an enhanced recruitment of mTORC1-Rheb complexes to the lysosome during recovery. These data suggest nonprotein dietary factors influence the postexercise regulation of mRNA translation in human skeletal muscle.

Life history parameters of the microtype parasitoid fly Pales pavida (Diptera: Tachinidae), and effects of host age and number of eggs ingested by host on parasitism success

ABSTRACTWith the aim of developing better procedures for rearing the microtype tachinid fly Pales pavida (Meigen), we performed ecological studies in the laboratory using the natural host Mythimna separata (Walker), investigating larval development, mating behaviour, individual oviposition patterns and relationships between parasitisation and number of eggs ingested (NEI) per host. The host instar at the time of parasitoid egg ingestion significantly affected the development time of the immature parasitoid: development took longer when the hosts ingested eggs when at the fifth instar than at the sixth (last) instar. There was no difficulty obtaining mated females in the laboratory when day 0–1 female flies were kept with day 2–4 males. Mean lifetime fecundity was 5805 ± 568 eggs per female. Daily rates of oviposition by individual females varied widely; the greatest number of eggs laid in a day was exactly 1700. When the NEI by day 1 fifth instars or day 0 or 3 last instars was 1, 3, 6 or 10, the parasitisation percentage tended to increase with increasing NEI, although it did not differ significantly between NEI 6 and 10. Therefore, the percentage adult emergence per egg ingested decreased from NEI 6 to 10, particularly in the case of last instars. Using day 0 last instars, with six eggs ingested per host, should increase parasitisation rates and shorten the development time of the parasitoid for rearing.

Effects of Maternal Dietary Egg Intake During Early Lactation on Human Milk Ovalbumin Concentration: A Randomized Controlled Trial

JR Metcalfe, JA Marsh, N D’Vaz. Clin Exp Allergy. 2016;46(12):1605–1613 To investigate how maternal dietary egg ingestion during the early postnatal period influences egg protein levels (ovalbumin [OVA]) in breast milk. Two thousand thirty-four pregnant women were initially screened for eligibility. One hundred and twenty breastfeeding mothers with a history of allergic disease (excluding egg allergy) whose infants were born at ≥36 weeks’ gestation were randomized to modify their diet for egg consumption during their infants’ first 6 weeks of life. This was a randomized controlled trial in which participants were allocated to 3 groups: high egg consumption (>4 eggs a …

SEROPREVALENCE OF TOXOPLAMA GONDII AMONG PRIMIGRAVIDA WOMEN AND THEIR NEONATES IN SOHAG GOVERNORATE, EGYPT

Infections with the Toxoplasma gondii parasite (T. gondii) occur worldwide and affect about one third of humanity. The study determined the prevalence of T. gondii among primigravidae Women and vertical transmission of T gondii in their newborns. Socio-demographic data and potential predisposing risk factors were studied using structured questionnaire. Venous blood samples (350 samples) were collected and tested for IgM & IgG anti-Toxoplasma gondii antibodies by enzymelinked immunosorbent assay (ELISA) during pregnancy period and at birth for primigravidae and their neonates, PCR test used as confirmatory test for IgM positive samples. Of the 350 pregnant women included in the study 165 (47.1%) cases were IgG seropositive of them 33 (9.4) cases were IgM seropositive. 185 (52.9%) cases were seropositive for Toxoplasma-specific IgG and IgM antibodies. At birth serological study of primigravidae and their neonates revealed that 142 (40.5%) cases were chronically infected, 25 (7.1%) cases showed active infection and 183 (52.2%) caseswere susceptible to infection; with prevalence of vertical transmission of 20% (5/25). Rural areas, contact with cats and ingestion of raw milk were statistically significantly associated with higher infection rates. Pigeon, sheep meat and ingestion of raw milk and egg represent the main source of infection in the studied area.

SEROPREVALENCE OF TOXOPLAMA GONDII AMONG PRIMIGRAVIDA WOMEN AND THEIR NEONATES IN SOHAG GOVERNORATE, EGYPT

Infections with the Toxoplasma gondii parasite (T. gondii) occur worldwide and affect about one third of humanity. The study determined the prevalence of T. gondii among primigravidae Women and vertical transmission of T gondii in their newborns. Socio-demographic data and potential predisposing risk factors were studied using structured questionnaire. Venous blood samples (350 samples) were collected and tested for IgM & IgG anti-Toxoplasma gondii antibodies by enzymelinked immunosorbent assay (ELISA) during pregnancy period and at birth for primigravidae and their neonates, PCR test used as confirmatory test for IgM positive samples. Of the 350 pregnant women included in the study 165 (47.1%) cases were IgG seropositive of them 33 (9.4) cases were IgM seropositive. 185 (52.9%) cases were seropositive for Toxoplasma-specific IgG and IgM antibodies. At birth serological study of primigravidae and their neonates revealed that 142 (40.5%) cases were chronically infected, 25 (7.1%) cases showed active infection and 183 (52.2%) caseswere susceptible to infection; with prevalence of vertical transmission of 20% (5/25). Rural areas, contact with cats and ingestion of raw milk were statistically significantly associated with higher infection rates. Pigeon, sheep meat and ingestion of raw milk and egg represent the main source of infection in the studied area.

Dietary phospholipids: lipid metabolism and risk factors for cardiovascular diseases

Eggs are a major source of phospholipids (PL) in the Western diet. Dietary PL have emerged as a potential source of bioactive lipids that may have widespread effects on pathways related to inflammation, cholesterol metabolism, and high-density lipoprotein (HDL) function. Based on pre-clinical studies, egg phosphatidylcholine (PC) and sphingomyelin appeared to regulate cholesterol absorption and inflammation. In clinical studies, egg PL intake is associated with beneficial changes in biomarkers related to HDL reverse cholesterol transport. Recently, egg PC was shown to be a substrate for the generation of trimethylamine N-oxide (TMAO), a gut microbe-dependent metabolite associated with increased cardiovascular disease (CVD) risk. More researches are warranted to examine potential serum TMAO responses to chronic egg ingestion and in different populations, such as diabetics. In this review, the recent basic science, clinical, and epidemiological findings examining egg PL intake and risk of CVD are summarized.

Egg ingestion in adults with type 2 diabetes: effects on glycemic control, anthropometry, and diet quality—a randomized, controlled, crossover trial

BackgroundThe inclusion of eggs as part of a healthful diet for adults with diabetes is controversial. We examined the effects of including eggs in the diet of adults with type...

Neurocysticercosis Presented with Acute Psychosis: A Case Report

Neurocysticercosis is the parasitic disease caused by ingestion of egg of Tinae Solium. The disease presents with spectrum of clinical manifestations like seizure, headache, neurological deficit and psychiatric symptoms such as psychosis. Even though most commonly patients of neurocysticercosis present with seizure, rarely, it may produce symptoms of neuropsychiatric disorder such as psychosis. Here, we are going to report a case of a patient who presented with features of acute psychosis. Later on with diagnostic imaging like CT and MRI, he was diagnosed as a case of multiple neurocysticercosis. He was then managed with anti psychotics, AEDs, Anti-helminthic drugs and steroids.Nepal Journal of Neuroscience 13:54-56, 2016

Effects of maternal dietary egg intake during early lactation on human milk ovalbumin concentration: a randomized controlled trial

There is limited understanding of how maternal diet affects breastmilk food allergen concentrations, and whether exposure to allergens through this route influences the development of infant oral tolerance or sensitization. To investigate how maternal dietary egg ingestion during early lactation influences egg protein (ovalbumin) levels detected in human breastmilk. In a randomized controlled trial, women were allocated to a dietary group for the first six weeks of lactation: high-egg diet (> 4 eggs per week), low-egg diet (one-three eggs per week) or an egg-free diet. Breastmilk samples were collected at 2, 4 and 6 weeks of lactation for the measurement of ovalbumin. The permeability of the mammary epithelium was assessed by measuring the breastmilk sodium : potassium ratio. Egg-specific IgE and IgG4 were measured in infant plasma at 6 weeks, and prior to the introduction of egg in solids at 16 weeks. Average maternal egg ingestion was associated with breastmilk ovalbumin concentration. Specifically, for each additional egg ingested per week, there was an average 25% increase in ovalbumin concentration (95% CI: 5-48%, P = 0.01). Breastmilk ovalbumin concentrations were significantly higher in the 'high-egg' group (> 4 eggs per week) compared with the 'egg-free' group (P = 0.04). However, one-third of women had no breastmilk ovalbumin detected. No detectable associations were found between mammary epithelium permeability and breastmilk ovalbumin concentrations. Infant plasma egg-specific IgG4 levels were also positively associated with maternal egg ingestion, with an average 22% (95% CI: 3-45%) increase in infant egg-specific IgG4 levels per additional egg consumed per week (P = 0.02). Increased maternal egg ingestion is associated with increased breastmilk ovalbumin, and markers of immune tolerance in infants. These results highlight the potential for maternal diet to benefit infant oral tolerance development during lactation.

Lipid‐lowering mechanism of egg yolk in normal rats

SummaryThe ingestion of egg has been reported to lower blood cholesterol, but the mechanism is unclear. Here, the biochemical metabolic mechanism by which the oral administration of egg yolk affects blood lipid reduction was investigated using normal rats. Blood triglycerides and total cholesterol were lower and high‐density lipoprotein cholesterol was higher in an egg yolk‐given group compared to other groups, while low‐density lipoprotein cholesterol was increased in the pork belly oil‐given group. HMG‐CoA reductase activity was higher in the pork belly oil‐given group, compared to an egg yolk‐given group, a weekly alternating administration of pork belly oil and egg yolk‐given group, and the saline‐given normal control group. However, faecal excretions of total sterol, neutral sterol and acid sterol in an egg yolk‐given group were higher compared to the pork belly oil‐given group, a weekly alternating administration of pork belly oil and egg yolk‐given group, and a normal control group. The results suggested that ingestion of egg decreased blood lipids.

Impacts of Intraguild Predation on Arctic Copepod Communities

Communities of large copepods form an essential hub of matter and energy fluxes in Arctic marine food webs. Intraguild predation on eggs and early larval stages occurs among the different species of those communities and it has been hypothesized to impact its structure and function. In order to better understand the interactions between dominant copepod species in the Arctic, we conducted laboratory experiments that quantified intraguild predation between the conspicuous and omnivorous Metridia longa and the dominant Calanus hyperboreus. We recorded individual egg ingestion rates for several conditions of temperature, egg concentration and alternative food presence. In each of these experiments, at least some females ingested eggs but individual ingestion rates were highly variable. The global mean ingestion rate of M. longa on C. hyperboreus eggs was 5.8 eggs ind-1 d-1, or an estimated 37% of M. longa daily metabolic need. Among the different factors tested and the various individual traits considered (prosome length, condition index), only the egg concentration had a significant and positive effect on ingestion rates. We further explored the potential ecological impacts of intraguild predation in a simple 1D numerical model of C. hyperboreus eggs vertical distribution in the Amundsen Gulf. Our modelling results showed an asymmetric relationship in that M. longa has little potential impact on the recruitment of C. hyperboreus (< 3% egg standing stock removed by IGP at most) whereas the eggs intercepted by the former can account for a significant portion of its metabolic requirement during winter (up to a third).

Development of Intrinsically Labeled Eggs and Poultry Meat for Use in Human Metabolic Research

Background: Stable isotope amino acids are regularly used as tracers to examine whole-body and muscle protein metabolism in humans. To accurately assess in vivo dietary protein digestion and absorption kinetics, the amino acid tracer is required to be incorporated within the dietary protein food source (i.e., intrinsically labeled protein).Objective: We assessed the practicality of producing eggs and poultry meat intrinsically labeled with L-[5,5,5-2H3]leucine through noninvasive oral tracer administration.Methods: A specifically formulated diet containing 0.52% leucine was supplemented with 0.3% L-[5,5,5-2H3]leucine and subsequently fed to 3 laying hens (Lohmann LSL Whites) for 55 d. On day 55, the hens were slaughtered and their meat, bones, and organs were harvested to determine tissue labeling. In Expt. 1, 2 healthy young men [mean ± SEM age: 22 ± 1.5 y; mean ± SEM body mass index (BMI; in kg/m2): 23.7 ± 0.5] ingested 18 g L-[5,5,5-2H3]leucine–labeled egg protein. In Expt. 2, 2 healthy young men (mean ± SEM age: 20.0 ± 0.0 y; mean ± SEM BMI: 26.4 ± 3.1) ingested 28 g L-[5,5,5-2H3]leucine–labeled poultry meat protein. Plasma samples (Expts. 1 and 2) and muscle biopsies (Expt. 1) were collected before and after labeled-food ingestion.Results: High tracer labeling [>20 mole percent excess (MPE)] in the eggs was obtained after 7 d and maintained throughout the feeding protocol (P < 0.05). Over a 55-d period, ∼850 g egg protein (145 eggs) was produced, with a mean ± SEM tracer enrichment of 22.0 ± 0.8 MPE. Mean ± SEM L-[5,5,5-2H3]leucine enrichment in the meat was 9.6 ± 0.1 MPE. In Expts. 1 and 2, the consumption of labeled eggs and poultry meat protein increased plasma L-[5,5,5-2H3]leucine enrichment, with mean ± SEM peak values of 6.7 ± 0.1 MPE and 4.0 ± 0.9 MPE, respectively. The mean ± SEM 5-h postprandial increase in myofibrillar L-[5,5,5-2H3]leucine enrichment after egg ingestion in healthy young men was 0.051 ± 0.008 MPE (Expt. 1).Conclusion: We demonstrated the feasibility of producing intrinsically labeled eggs and poultry meat for use in human metabolic research.