Comparative effects of zinc hydroxy chloride, zinc sulfate, and zinc-methionine on egg quality and quantity traits in laying hens.

The aim of this experiment was to evaluate the effect of different levels of zinc supplements on egg quality and quantity traits as well as egg enrichment with zinc in laying hens from 40 to 50 weeks of age. A total of 240 Hy-line laying hens were distributed among eight treatments and five replications (six birds per replication). The control group received no zinc diet, while the other treatments were supplemented with varying levels of zinc sulfate (80, 120, and 160 mg/kg) or zinc hydroxy chloride (50, 75, and 100 mg/kg). An additional group of zinc-methionine supplement at 124 mg/kg was also included. Results showed that different levels of zinc supplementation caused a significant improvement in eggshell resistance, eggshell percentage, feed conversion ratio, and Haugh unit compared to the control group. Adding organic and hydroxy sources of zinc significantly increased zinc contents in egg yolk, tibia bone, and blood. In addition, the treatments containing zinc supplements caused an increase in the antibody level against the Newcastle disease compared to the control (P < 0.05). Different levels and sources of zinc had no significant effect on eggshell thickness, specific gravity, and egg mass. Results showed that adding zinc in hydroxy chloride form at 100 mg/kg could improve performance indices, safety, and egg enrichment with zinc.

Effects of substitution of crude palm oil with palm-pressed fibre oil on the laying hen's performance, egg production and egg quality traits.

This study aimed to evaluate the effects of substituting a crude palm oil (CPO) diet with palm-pressed fibre oil (PPFO) on laying hens' performance, egg production, carcass characteristic and egg quality. A total of 150 Hisex Brown laying hens were randomly assigned to five treatments: a basal diet containing 4% CPO (T1-control) and basal diets in which CPO was substituted by 25% (T2), 50% (T3), 75% (T4) or 100% (T5) PPFO. These diets were fed to laying hens ad libitum for 16 weeks. Compared to the T1 diet, dietary treatments T2, T3 and T4 had no significant effect (P > 0.05) on the feed intake, body weight gain, feed conversion ratio, egg number, egg production, egg weight and egg mass of the laying hens during the entire experimental period. Nonetheless, a significant (P < 0.05) reduction in feed intake, egg number, egg production and egg mass were observed in hens fed T5 compared to those fed the T1 (control) diet. Except for heart and spleen weights, other carcass characteristics were not affected by treatment (P < 0.05). Skin yellowness and breast meat redness increased significantly (linearly, P < 0.05) with increasing proportions of PPFO. Likewise, yolk colour scores increased in proportion to the dietary level of PPFO (linearly, P < 0.05). These findings suggest that PPFO can be used as a novel, cost-effective lipid source at a level of 3% in layer diets as a substitute for CPO to improve eggs' quality parameters without any harmful effects on laying performance.

SERS-based Ag NCs@PDMS flexible substrate combined with chemometrics for rapid detection of foodborne pathogens on egg surface.

An innovative method is introduced based on the combination of label-free surface-enhanced Raman scattering with advanced multivariate analysis. This technique allows both quantitative and qualitative assessment of Salmonella typhimurium and Escherichia coli on eggshells. Using silver nanocubes embedded in polydimethylsiloxane, we consistently achieved Raman spectra of bacteria. The stability of the Ag NCs@PDMS substrate is confirmed using rhodamine 6G over 30 days under standard conditions. Principal component analysis (PCA) effectively distinguishes between S. typhimurium and E. coli spectra. Partial least squares regression (PLS) models were developed for quantitative determination of bacteria on egg surfaces, yielding accurate results with minimal error. The S. typhimurium model achieves Rc2 = 0.9563 and RMSEC = 0.601 in calibration, and Rv2 = 0.9113 and RMSEV = 0.907 in validation. Similarly, the E. coli model achieves Rc2 = 0.9877 and RMSEC = 0.322 in calibration, and Rv2 = 0.9606 and RMSEV = 0.579 in validation. Recoveries validate PLS predictions by inoculating egg surfaces with varying bacterial amounts. Our study demonstrates the feasibility of SERS-PLS for quantitative determination of S. typhimurium and E. coli on eggshells, promising enhanced food safety protocols.

Determining the optimal level and the effect of different zinc sources on performance, egg quality and the immune system of laying hens at the end of the production period.

BACKGROUND: Trace elements, such as zinc, magnesium and copper, are essential for improving the performance and health of broiler breeders and the development of chicken embryos. These elements are integral to various proteins involved in metabolism, hormone secretion and the immune system, necessitating their inclusion in small amounts in poultry diets. OBJECTIVES: This study aimed to determine the optimal level and effect of different zinc sources on performance, egg quality and the immune system of laying hens at the end of the production period. METHODS: The experiment involved 520 Lohmann LSL laying hens, aged 80 weeks, divided into 13 treatments with 5 replications and 8 birds per replication. The hens were fed diets supplemented with 40, 60 and 80 mg/kg of zinc from various sources: mineral zinc oxide, mineral zinc sulphate, organic zinc chelated with glycine and organic zinc chelated with an organic acid. Key parameters measured included body weight, egg weight and immune response. RESULTS: The basal diet contained 63.58 mg/kg of zinc, with the requirement per the Lohmann LSL guideline being 80 mg/kg. Zinc supplementation significantly increased body weight in the second month, with 80 mg/kg being the optimal dose. Zinc oxide notably increased egg weight compared to the control. The hens utilized zinc from all sources, resulting in weight gain and improved parameters such as egg quality. Immune parameters were also positively influenced by zinc supplementation. CONCLUSIONS: Zinc supplementation at appropriate levels enhances the performance and egg quality of laying hens, particularly at the end of the production period. It improves bioavailability, enriches eggs and mitigates age-related declines in productivity.

Heavy metal contamination in eggs on poultry farms and ecological risk assessment around a gold mine area in northern Thailand.

The aim of this study was to analyze and compare the Hg, Pb, Cd, and Mn levels in egg feed, soil, and water among laying hens, laying ducks, and free-grazing duck farms in contaminated and uncontaminated areas. This study revealed that the Hg concentration in the eggs of free-grazing ducks was significantly greater than that in the eggs of laying hens and ducks in both contaminated and uncontaminated areas. However, the Pb and Mn levels in the eggs of laying ducks and free-grazing ducks were significantly greater than those in the eggs of laying hens in the contaminated area. Unfortunately, the Hg, Pb, Cd, and Mn concentrations in the feed, soil, and water from these three farms in both areas were not significantly different (P > 0.05). Hg and Cd were confirmed to be enriched in the egg albumin fraction, while Pb and Mn were found mainly in the egg yolk. However, egg consumption from free-grazing duck farms was the riskiest to Hg, Pb, and Mn contamination in the contaminated area. Additionally, the ecological risk factor (ER) in the soil revealed that all the farms were at considerable to high environmental risk for Cd except for Hg and Pb. Although the potential ecological risk index (RI) indicated a moderate risk for all farms in both contaminated and uncontaminated areas, these results were not consistent with our hypothesis. Therefore, the information gained in this study could be useful for setting up mitigation strategies and making decisions about public health concerns related to health hazards, especially for ecological risk assessments of heavy metal contamination.

Unveiling the emerging trends of egg components-based biodegradable food packaging development: A comprehensive review.

Food packaging plays a crucial role in the food supply chain by aiding in food preservation and reducing food losses throughout the distribution process. The extensive, unregulated utilization, and waste mismanagement of food packaging materials made up of conventional petroleum-based plastics has led to a significant environmental crisis. Egg components-based food packaging has attracted considerable attention from the global packaging industry as a viable alternative to synthetic polymers due to its biodegradability, sustainability, and health-related benefits. This comprehensive review explores the composition and properties of egg components (eggshell, eggshell membrane, egg white, and egg yolk), and recent advancements in biodegradable packaging films derived from them. Additionally, it introduces the characteristics of these films and their applications in food, highlighting their biodegradability, sustainability, and suitable mechanical, barrier, thermal, optical, antioxidant, and antimicrobial properties as substitutes for traditional synthetic polymers. The utilization of various egg components in the packaging industry is a safe, non-toxic, cost-effective, and economical approach. However, it was found that incorporating active compounds from natural sources into packaging films, as well as composite films composed of egg components combined with other biopolymers, resulted in superior properties, compared to single component films. Moreover, the application of novel technologies in film development has proven to be more effective than conventional methods. These innovative egg components-based packaging films can be optimized and commercialized for use as packaging materials for food products.

Temporal trends (1972-2017) and spatial differences of persistent halogenated aromatic hydrocarbons in osprey eggs in Finland.

Time trends and regional differences of polychlorinated dibenzo-p-dioxins and -furans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), DDTs, polybrominated biphenyls (PBBs) and polybrominated diphenylethers (BDEs) were studied in unhatched osprey eggs collected by bird ringers in 1972-2017 from four areas in Finland. Two study areas were from Baltic Sea, Northern Quark and Finnish Archipelago Sea, while the two others were inland lake areas, eutrophicated Lake Vanajanselkä affected by industrial emissions, and Pristine SW Lake Area. The highest concentrations of most compound groups were in Lake Vanajanselkä consistent with high emissions, the predominance of bream as a prey, and higher concentrations in bream compared to other prey fish. Concentrations of all chlorinated compounds decreased significantly in all study areas. Average annual decreases were ∑PCDD/F 2.3-4.9%, ∑PCB 2.2-4.2%, ∑PCN 2.6-7.0% and ∑DDT 7.1-9.5%, primarily in line with decreased levels in prey fish. From 1972 PBBs and BDEs increased significantly until 1990s declining rapidly thereafter. PCDD/F congener profile was dominated by 2,3,4,7,8-PeCDF, except in Lake Vanajanselkä by 1,2,3,6,7,8-HxCDD. PCB congener profile was dominated by PCB 153 in all study areas, followed by PCB 180 and PCB 138. Among dioxin-like compounds PCBs contributed 82%, PCDDs 14% and PCDFs 4% to toxic equivalent quantity (∑TEQ). PCB 126 contributed most to ∑TEQ, followed by 1,2,3,7,8-PeCDD. BDE 47 being the dominant BDE congener, followed by BDE 100. ∑DDT concentrations were relatively similar across all study areas, with DDE contributing about 90%. Productivity of chicks per active nest was significantly decreased in Lake Vanajanselkä, and the likely explanation is embryotoxicity of dioxin-like compounds. It is plausible that dioxin-like compounds influenced embryonic survival among highly exposed ospreys prior to 2010, especially in Lake Vanajanselkä and Northern Quark. However, decreased survival due to DDE-induced eggshell thinning seems unlikely after 1985, and BDE levels were below those potentially causing adverse effects.

Changes of Potent Odorants in Salted Duck Egg Yolk before and after Roasting.

As the second most widely consumed eggs, duck eggs are made into preserved eggs, salted duck eggs, and roasted duck eggs to extend their shelf-life. To investigate the differences in potent odorants (POs) between salted duck egg yolk (SDEY) and roasted duck egg yolk (RDEY), the volatiles in SDEY and RDEY were extracted through solvent extraction coupled with solvent-assisted flavor evaporation and were assayed with gas chromatography-mass spectrometry-olfactometry. A total of 45 volatiles were identified in two samples, 24 odor-active compounds (OACs) were screened, and more OACs were in RDEY. The flavor-dilution (FD) factors of OACs were obtained by aroma extract dilution analysis and ranged from 3 to 6561. Twenty-two OACs with FD factors ≥ 9 were quantitated, and the results indicated the concentrations of OACs in yolk increased greatly after salted duck eggs were roasted. Based on the concentrations and thresholds, odor activity values (OAVs) were determined; 17 odorants with OAVs ≥ 1 were determined as POs. Acetoin was the most PO in SDEY; there were more POs in RDEY, including 2-ethyl-3,6-dimethylpyrazine, acetoin, 2-acetyl-3-methylthiophene, dihydro-4-hydroxy-2(3H)-furanone, etc. The outcomes obtained have reference values for making better use of duck eggs in the food industry.

[Egg components involved in cognitive function]. / Componentes del huevo implicados en la función cognitiva.

Introduction: Interest in the relationship between diet and cognitive function has increased in recent years. In this sense, eggs contain many essential nutrients that are also beneficial for cognitive function. Several studies have shown that moderate egg consumption not only does not increase cardiovascular risk but is positively associated with better cognitive performance and a lower risk of dementia. Egg protein is particularly rich in tryptophan, which is a precursor to serotonin, the neurotransmitter involved in mood, and melatonin, the hormone that regulates the sleep-wake cycle. Consumption of tryptophan-rich egg hydrolysates has been associated with improved attention and reduced feelings of sadness or depression. Egg choline is needed for the synthesis of acetylcholine, the neurotransmitter involved in memory and learning, and also for the synthesis of phosphatidylcholine, the intake of which has been linked to better mental function and a lower risk of dementia in adults. Choline intake during pregnancy reduces the risk of neural tube defects and is associated with better offspring development. And lutein and zeaxanthin, which are particularly concentrated in the nervous system, are associated with better visual function and cognitive development in the offspring and also in the elderly. All this evidence confirms the importance of including eggs in a balanced diet to prevent cognitive decline and improve cognitive health throughout life.

Introducción: El interés por la relación entre la dieta y la función cognitiva ha aumentado en los últimos años. En este sentido, el huevo tiene numerosos nutrientes esenciales que son, además, beneficiosos para la función cognitiva. Diferentes estudios han demostrado que el consumo moderado de huevo no solo no aumenta el riesgo cardiovascular, sino que se asocia positivamente con un mejor desempeño cognitivo y un menor riesgo de demencia. La proteína del huevo es especialmente rica en triptófano, que es precursor de la serotonina, el neurotransmisor implicado en el estado de ánimo, y de la melatonina, la hormona que regula los ciclos de sueño-vigilia. La ingesta de hidrolizados de huevo ricos en triptófano se ha asociado con una mejor atención y una menor sensación de tristeza o depresión. La colina del huevo es necesaria para la síntesis de la acetilcolina, el neurotransmisor implicado en la memoria y el aprendizaje, y también para la síntesis de la fosfatidilcolina, cuya ingesta se ha relacionado con una mejor función mental y un menor riesgo de demencia en adultos. La ingesta de colina durante el embarazo disminuye el riesgo de defectos del tubo neural y se asocia a un mejor desarrollo del descendiente. Y la luteína y la zeaxantina, que se concentran especialmente en el tejido nervioso, se relacionan con una mejor función visual y desarrollo cognitivo del recién nacido y también del adulto mayor. Todas estas evidencias confirman la importancia de consumir huevo como parte de una dieta equilibrada para prevenir el deterioro y mejorar la salud cognitiva a lo largo de la vida.

Levels of PCDD/Fs, PCBs, metals and rare earth elements in eggs and vegetables from areas with different environmental contamination impacts in the Campania region (Southern Italy).

Studying the links between environmental pollution and the levels of contamination in food is an important challenge to ensure human health. Matched samples of eggs from free-range hens and vegetables were analysed to investigate the bioaccumulation of PCDD/Fs, PCBs, metals and rare earth elements. Only two egg samples resulted above the limit fixed for PCDD/Fs and the action level set for DL-PCBs. The highest concentrations were found in the eggs from an area situated in a big city affected by strong urbanisation. Although eggs and vegetables were subjected to the same environmental pollution, the PCDD/F and PCB bioaccumulation that occurred in the eggs was much higher than those in vegetables (p < 0.01). In vegetables, the highest PCDD/F and PCB concentrations were found in lettuce and potatoes grown on contaminated soil. Higher bioaccumulation of Fe and Zn occurred in eggs compared to vegetables; La, Pr, Nd, Sm and Eu were found only in lettuce samples. The results of this study may provide important data useful in the risk assessment of human exposure through diet in accidents involving dangerous chemicals. Furthermore, the estimated weekly intakes calculated for PCDD/Fs and PCBs highlighted that, although vegetables accumulate very low concentrations of these contaminants, they contribute more than eggs to human exposure.