Yolk Cholesterol Content Research Articles

Hepatic fatty acids profile, oxidative stability and egg quality traits ameliorated by supplementation of alternative lipid sources and milk thistle meal.

This study assessed the effects of different levels of milk thistle (Silybum marianum) meal (MTM) on egg quality traits, oxidative stability, blood biochemical parameters and liver health indices in laying hens receiving diets supplemented with lipid from different sources. For this purpose, Leghorn laying hens (Hy-Line W-36) were randomly assigned to 12 experimental treatments with eight replicates of five birds each. Dietary treatments consisted of four dietary fat sources (fish oil, sunflower oil, poultry oil and fat powder, each with different fatty acid profiles) and three levels of MTM (0.0, 15 and 30g/kg) offered through 10days of adaptation and 70days of main recording. Results showed that dietary inclusion of polyunsaturated fatty acids, including fish or sunflower oils, reduced serum cholesterol content but increased blood malondialdehyde (MDA) concentration (p<0.05). While fish oil improved the yolk colour index and Haugh unit (p<0.05), it decreased yolk cholesterol concentration (p<0.01). The highest hepatic glycogen content and tissue integrity as well as the lowest liver lipid percentage and MDA content were observed in birds fed diets supplemented with poultry oil. On the other hand, feeding 30g/kg of MTM reduced not only hepatic lipid percentage but also aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities (p<0.01), while it improved eggshell strength and thickness (p<0.05). Supplementation of fat powder enhanced hepatic C16:0 content, while addition of poultry, sunflower or fish oil increased C18:1, C18:2 or C20:5 concentrations respectively (p<0.01); nonetheless, feeding the highest level of MTM reduced hepatic ΣSFA but increased Σn-3 fatty acids (p<0.01). The interaction effects indicated that fish or sunflower oil supplementation increased the MTM level required to reduce not only serum or egg cholesterol concentrations (p<0.05) but also blood or hepatic MDA content (p<0.01). It was concluded that fish oil and MTM (30g/kg) supplements might improve internal egg quality traits and eggshell quality respectively. The hepatic fatty acid profile was also found strongly correlated with dietary fatty acids. Finally, the best hepatic health indices and the highest oxidative stability were achieved when the birds were fed diets supplemented with poultry oil and 30g/kg of MTM.

The chemical composition of free-range and conventionally-farmed eggs available to Canadians in rural Nova Scotia.

In rural Nova Scotia (NS), many small family farms raise free-range hens that consume a varied diet that is different from that of conventionally-farmed hens in caged housing systems. However, it is not known how this varied diet impacts the quality of these eggs. The objective of the present study was to compare the chemical composition of free-range eggs obtained from a small family farm in rural NS to that of conventionally-farmed eggs purchased from a local grocery store. The values obtained from the present study were also compared to published values in the Canadian Nutrient File (CNF) and the U.S. Department of Agriculture FoodData Central database. The egg components and the amino acid compositions were evaluated, and protein concentrations were determined using the Kjeldahl method whereas the fatty acid profiles of the egg yolks were determined using gas chromatography. No difference (P = 0.3) in protein content was observed in free-range eggs (10.6 ± 1.1%) compared to conventionally-farmed eggs (9.7 ± 0.6%). Similar values were also observed for the physical properties of the two types of eggs measured except for the weights of the egg shells. Conversely, the amino acid cysteine, was in higher amounts (P = 0.05) 0.26 g/100 g in the CNF compared to the measured values of ~0.16 g/100 g. Notably, the polyunsaturated linoleic acid (C18:2n-6) was higher (P = 0.001) in the free-range eggs (45.6%) compared to (40.8%) the conventionally-farmed eggs. The cholesterol content of egg yolks was lower in free-range eggs (253.4 ± 0.01 mg/extra-large yolk or 14 mg cholesterol/g of yolk) vs. for conventionally-farmed eggs (263 ± 0.7 mg/extra-large yolk or 15.4 mg cholesterol/g of yolk), respectively. In terms of protein nutrition, free-range eggs may be a suitable alternative to conventionally-farmed eggs, moreover, the lower cholesterol content may be a favourable attribute for Canadian consumers who wish to purchase local free-range eggs.

Egg Quality Parameters, Production Performance and Immunity of Laying Hens Supplemented with Plant Extracts.

Simple SummaryThe current study aimed to investigate the effects of a combination of two plant extracts Mentha arvensis and Geranium thunbergii in drinking water. A complete randomized design was performed to study the effects on production performance, egg quality parameters, sensory qualities, proximate analysis, and cholesterol content of egg yolk and immunity parameters in laying hens. The data suggested that the supplementation of plant extracts could improve the laying performance, egg quality and immunity, and decrease the egg yolk cholesterol content in a dose-dependent manner.This study examined the effects of Mentha arvensis (MA) and Geranium thunbergii (GT) extracts in drinking water on the production performance, egg quality, cholesterol content of egg yolk, proximate composition, and sensory qualities of egg and immunity parameters in laying hens. Ninety-six 28-week-old Hy-Line Brown layers were randomly divided into four dietary treatments for 16 weeks. The dietary treatments were (1) control, (2) T1 (0.01% 1 MA:1 GT), (3) T2 (0.05% 1 MA:1 GT), and (4) T3 (0.1% 1 MA:1 GT). Egg production increased significantly with increasing levels of MA and GT. The egg weight was increased in T2, and the feed intake was highest in T2 and T3 (p < 0.05). The Haugh unit and egg shape index were significantly better in T3 and the control than with other treatments (p < 0.05). The content of yolk cholesterol was significantly lower (p < 0.05) in T2 and T3. On the other hand, there were no significant differences in the egg proximate composition. A significant increase in the serum interleukin 6 (IL-6), tumor necrosis factor (TNFα) and immunoglobulins (IgG and IgA) concentration was observed in the birds fed plant extracts when compared to the control. On average, T2 and T3 showed significantly lower (p < 0.05) concentrations of NH3 gas from the feces as compared to the control. This study suggests that MA and GT supplementation could improve the laying performance, egg quality, and immunity, and decrease the egg yolk cholesterol content in a dose-dependent manner.

Cholesterol Content, Fatty Acid Profile and Health Lipid Indices in the Egg Yolk of Eggs from Hens at the End of the Laying Cycle, Following Alpha-Ketoglutarate Supplementation.

The current study aimed to assess the effects of dietary alpha-ketoglutarate (AKG) supplementation to laying hens on the fatty acid (FA) profile and cholesterol levels of the egg yolk at the end of production cycle. The experiment was performed on forty-eight Bovans Brown laying hens randomly assigned to either a control group (CONT) or a group supplemented with AKG. The CONT group was fed the basal diet, and the AKG group was fed the basal diet plus 1.0% AKG from the 31st until the 60th week of age, when FA profile, fat and cholesterol content of the egg yolks were determined. No significant changes in the cholesterol and total fat content of the egg yolks were observed. However, there were positive (the decrease in n-6 FA and the increase in MUFA), and negative (decrease in PUFA and n-3 FA, increase in TI and n-6/n-3 ratio) changes in FA profile following AKG supplementation. In conclusion, it was shown that dietary AKG after a 30-week long supplementation influence FA profile in egg yolk and its nutritional value.

Sanguinarine improved nutrient digestibility, hepatic health indices and productive performance in laying hens fed low crude protein diets.

A major mean to minimize feeding costs and faecal nitrogen excretion on poultry farms is to decrease the supplied dietary protein content. This, however, is associated with the declines in productive performance and systemic health indices. Sanguinarine may improve protein efficiency via decreasing the intestinal amino acid decarboxylation and stimulating the tryptophan‐serotonin pathway. The present study was carried out to investigate the effects of dietary supplementation of sanguinarine on the performance, egg yolk biochemical parameters, serum enzyme activities, nutrient digestibility, ovarian follicles, and hepatic health indices in laying hens fed decremental levels of crude protein (CP). For this purpose, 180 laying hens were allocated into nine dietary treatments with four replicates of five birds each. The experimental treatments consisted of three levels of CP (85.0%, 92.5%, and 100% of Hy‐Line W‐36 manual recommendation) and three levels of sanguinarine (0.00, 3.75, and 7.50 mg/kg) in a 3 × 3 factorial arrangement administered during a 70‐day feeding trial. Results showed that the decremental levels of CP led to significant increases in serum aspartate aminotransferase (p < .05), alanine aminotransferase, and alkaline phosphatase (p < .01) activities, egg yolk cholesterol concentration (p = .064), and hepatic fat and malondialdehyde (MDA) contents (p < .05). It also caused the significant declines in ileal dry matter (DM) digestibility (p < .05) and eggshell strength (p < .05), and also tended to decrease CP digestibility (p = .071), Haugh unit (p = .057) and egg production percentage (p = .062). The interaction effects of the experimental factors indicated that dietary supplementation of sanguinarine, especially at 7.50 mg/kg, led to significant improvements in serum aspartate aminotransferase and alanine aminotransferase activities (p < .01), egg yolk cholesterol (p < .001) and triglyceride (p < .05) concentrations, eggshell strength (p < .001), Haugh unit (p < .05), hepatic fat (p < .001) and MDA (p = .059) contents, ileal DM and CP digestibility (p < .01) as well as egg production, egg mass and feed conversion ratio (FCR; p < .05) in birds receiving decremental levels of CP. Taken together, the results indicate that dietary administration of sanguinarine could enhance productive performance via improving nutrient digestibility, hepatic health indices and fortifying systemic antioxidant capacity in laying hens fed low‐CP diets.

The Effect of Supplementing Tea Polyphenols in Diet of Laying Hens on Yolk Cholesterol Content and Production Performance

ABSTRACT This study was conducted to evaluate the influence of supplementing tea polyphenols (TP) in diet of laying hens on yolk cholesterol content and production performance. A total of 1800 Lohmann laying hens aged 48 weeks were randomly allocated to 6 groups. Each group consisted of 6 replicates with 50 layers. The feeding experiment was 4 weeks including one-week acclimatization. Layers fed basal diet supplemented with 0, 150, 200, 250, 300 and 350 mg TP/kg diet, respectively. The results showed that average daily feed intake (ADFI), feed conversion ratio (FCR), average egg weight (AEW), laying rate and the indicators of egg quality were not significantly affected by the diet supplemented with 300 mg/kg TP (p>0.05). However, yolk cholesterol content decreased by increasing TP concentration (p<0.01), with 18.06% reduction in layers fed diet supplemented with 300 mg TP/kg. Also, the diet supplemented with 300 mg/kg TP significantly decreased plasma triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) level (p<0.05). The activity of serum glutathione peroxidase (GSH-Px) was enhanced by increasing TP concentration, while the content of serum methane dicarboxylic aldehyde (MDA) was decreased by increasing TP concentration. The highest activity of GSH-Px and the lowest serum MDA content were both determined in 300 mg/kg TP group (p<0.01). In conclusion, this study suggests that the addition of 300 mg TP/kg basal diet had no negative effect on the production performance laying hens, yet decreased the egg yolk cholesterol content and enhanced the antioxidant capacity of laying hens at the same time.

Omega-3 fatty acids reduce the negative effects of dexamethasone-induced physiological stress in laying hens by acting through the nutrient digestibility and gut morphometry

In this study, the effects of omega-3 fatty acids on egg production, nutrients digestibility, eggs yolk lipid peroxidation, and intestinal morphology in laying hens under physiological stress were investigated. Ninety-six 35-wk-old Lohmann LSL-Lite laying hens were used in 2 × 3 factorial arrangement with 2 levels of dexamethasone (DEX) (0 and 1.5 mg/kg of the diet) and 3 levels of omega-3 fatty acids (0, 0.24, or 0.48% of the diet) in a completely randomized design. At 41 wk of age, the stress groups were continuously fed with a DEX 1.5 mg/kg diet for 1 wk. Egg production, egg mass, feed intake, egg weight, and feed conversion ratio were recorded. In addition, the AME, digestibility of CP, crude fat (CF), and organic matter were measured during the stress induction period. At the end of 41 wk of age, malondialdehyde and cholesterol concentrations in the egg yolk and intestinal morphology were investigated. The results showed that egg production, egg mass (P < 0.0001), egg weight (P = 0.043), and BW (P = 0.0005) were lower in DEX layers. Feed intake was reduced by the interaction between DEX and omega-3 fatty acid (P = 0.042). Malondialdehyde value (P = 0.002) and cholesterol concentration (P = 0.001) in egg yolk increased by DEX administration. The combination of DEX administration and omega-3 fatty acids supplementation was found in the indices of intestinal morphology such as villus height and width and crypt depth (P < 0.05). Administration of DEX decreased the CP digestibility (P < 0.0001) and AME (P = 0.006). Digestibility of CF and AME in the group of 0.48% omega-3 fatty acids were higher (P < 0.05) than those of 0 and 0.24%. In conclusion, we found that dietary omega-3 fatty acids had beneficial effects on gut morphology and nutrient digestibility in laying hens under physiological stress. However, they could not alleviate the negative effects of physiological stress on performance.

Lycopene supplementation does not change productive performance but lowers egg yolk cholesterol and gene expression of some cholesterol-related proteins in laying hens

ABSTRACT 1. This work examined the effects of purified lycopene (LYC) supplementation or a source of LYC as tomato powder (TP) on productive performance, egg yolk cholesterol levels as well as gene expression related to mechanism and regulation of cholesterol. 2. One hundred and fifty laying hens (Lohman LSL, hybrid) were randomly divided into one of three treatments, with 10 replicates of five hens per cage, totalling 50 hens per treatment. The hens were fed either a standard diet (control) or a standard diet supplemented with 20 mg purified lycopene/kg diet (LYC) or an equal amount of lycopene-containing tomato powder (TP) for 12 weeks. 3. Feed consumption, egg production, and feed efficiency remained similar among treatments (P ≥ 0.27). Supplementing lycopene, either as a purified form or in TP, increased the levels of serum and egg yolk lycopene and reduced serum and egg yolk cholesterol concentrations (P < 0.001). Supplementation in either form decreased gene expression for intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but increased hepatic ABCG5 and ABCG8 (P < 0.001). 4. The results of the present work revealed that egg yolk cholesterol metabolism is regulated by the modulation of a group of genes, particularly with LYC supplementation.

Thicker Shell Eggs with Enriched N-3 Polyunsaturated Fatty Acids and Lower Yolk Cholesterol Contents, as Affected by Dietary Nettle (Urtica cannabina) Supplementation in Laying Hens.

Simple SummaryThe nettle Urtica cannabina (U. cannabina) belongs to the Urticaceae (nettle) family in the major group Angiosperms (flowering plants); it is distributed worldwide in temperate regions. While it was previously considered to be a weed, increasing evidence suggests that it is a valuable nutrient resource and has multiple biological functions when included in both human and animal diets. U. cannabina was given to laying hens in this experiment to study its effect on the hens’ performance, egg quality, yolk fatty acids composition, and serum biochemical parameters. The results revealed that dietary supplementation with U. cannabina has the potential to produce high-quality eggs. The data collected in this experiment can be used to inform further use of this plant to improve the lipid profile and fatty acid composition of eggs produced by hens fed on U. cannabina.The nettle Urtica cannabina (U. cannabina) is not only a functional edible food for humans but also a potential alternative feed resource for poultry, providing protein, fatty acids, vitamins, and minerals. The present study was conducted to evaluate the effects of dietary U. cannabina on the production of high-quality eggs with enriched n-3 polyunsaturated fatty acids (PUFA) and lower cholesterol contents. One hundred and twenty laying hens were assigned to three groups [control, 15% alfalfa meal supplementation (TRTA), and 15% U. cannabina supplementation (TRTU)]. The results showed that the feed intake, yolk color, and shell thickness were increased (p < 0.05) in the U. cannabina group. Moreover, cholesterol contents of the yolk and serum were lower in the U. cannabina group (p < 0.05). The total n-3 PUFA concentration in the yolk was increased while the ratio of n-6/n-3 was reduced in the U. cannabina group (p < 0.01). In conclusion, the dietary inclusion of U. cannabina increased shell thickness, yolk n-3 PUFA levels, and yolk color, and reduced cholesterol contents of the yolk and serum without any negative impacts on health or laying performance.

Study of Local Duck Rations from Colocasia Esculenta Flour on Egg Production and Cholesterol Content

Colocasia esculenta is the plants feed ingredients shown to reduce the cholesterol content of livestock products, such as in ducks. This study aims to examine the use of Colocasia esculenta Scho. plant in local duck rations on egg production, and the content of cholesterol and triglycerides. As a treatment in this study were the level of use of Colocasia esculenta meal (CM), 0%, 5%, 10%, 15% and 20%, with 4 replications, which designed with a completely randomized design. As many as 80 ducks in the laying period were used, ranging in age from 19 to 30 weeks. The data obtained showed that an increasing level of CM up to 10% resulted in increased egg production, egg weight and decreased feed convertion ratio. Conversely, the blood and yolk total cholesterol and triglyceride content actually decreased until the level CM was 20%. It was concluded that the use of CM up to a level of 10% could improve the performance of egg production, and the use of up to a level of 20% decreased the cholesterol and triglyceride content of blood and egg yolk. This is an important role about those subject for required healthy food for human nutrition

Effects of dried thyme (Thymus vulgaris L.) leaves on performance, some egg quality traits and immunity in laying hens

The aim of the present study was to investigate the usage of thyme leaves and its effects on performance, some egg quality traits and humoral immunity in laying hens. A total of 108 laying hens aged 36 weeks were randomly assigned to three dietary groups for 16 weeks. Dried and ground (Thymus vulgaris L.) thyme leaves were used at the level of 0, 1 and 2% in the diets of groups. Feed intake, body weight, egg production, egg weight and egg quality characteristics were not affected by dietary thyme supplementation. Thyme supplementation at 2% resulted in beneficial effects in laying hens due to the lowering of yolk cholesterol and total saturated fatty acids concentration while increasing omega-3 fatty acids. Furthermore, the yolk malondialdehyde, blood serum cholesterol and triglycerides levels were reduced and antibody titers against SRBC were increased with 2% thyme supplementation. In conclusion, the results showed the antioxidative and hypolipidemic effects of thyme supplementation in laying hens along with improved humoral immune response without any negative effects on performance and egg quality characteristics.

Lycopene Supplementation Either Purified or as in Tomato Powder to the Diet of Laying Hens Lowers Egg Yolk Cholesterol by Modulation of Sterol Transporters

Abstract Objectives The objective of this work was to investigate the effects of dietary supplementation of purified lycopene (LYC) or a source of LYC as in tomato powder (TP) on live hen performance, egg yolk cholesterol concentrations as well as the gene expressions related to mechanism and regulation of cholesterol, namely Niemann-Pick C1-like 1 protein (NPC1L1), acyl-CoA: cholesterol acyltransferase 2 (ACAT2), microsomal triacylglycerol transport protein (MTP), ATP binding cassette transporters sub-family G member 5 and 8 (ABCG5/8), ATP citrate lyase (ACLY), liver X receptor alpha (LXRα) and sterol regulatory element-binding proteins (SREBP1c). Methods A total of 150 20-week-old white laying hens were divided into one of 3 treatments, with 10 replicates of 5 hens per cage, totaling 50 hens per treatment. The birds were fed either a basal diet (Control) or basal diet supplemented with 20 mg purified lycopene/kg diet (LYC) or an equal amount of lycopene-containing tomato powder (TP) for 12 weeks. Results Feed intake, egg production and feed conversion ratio remained similar among treatments (P ≥ 0.27). However, egg weights from hens fed a diet supplemented with lycopene particularly the purified form were greater (P = 0.036). Supplementing lycopene either purified or as in TP increased the concentrations of serum and egg yolk lycopene but decreased serum and egg yolk cholesterol concentrations (P &amp;lt; 0.001). Supplementing LYC purified or as in TP decreased the gene expression of intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but increased hepatic ABCG5 and ABCG8 (P &amp;lt; 0.001). The gene expressions were more pronounced with TP supplements compared with that of the LYC supplements. Conclusions The results of the present work revealed that egg yolk cholesterol metabolism is downregulated through decreased activities of intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but upregulated with increased hepatic activities of ABCG5 and ABCG8. Funding Sources Small and Medium Enterprises Development Organization of Turkey (KOSGEB) Turkish Academy of Sciences.

The Effect of Using Natural Feed Additive on Egg Production and Quality of Mojosari Duck (Anas plathyrhynchos)

The aim of this study was to determine the effect of using natural feed additives on egg production and quality of Mojosari Ducks. The animals used were 81-layer period Mojosari ducks 145 days old with an average egg weight 67.55 g and a coefficient diversity 8.98%. Each bird placed in experimental cages 2.25 x 2.25 m. Each plot (experimental unit) placed 3 ducks. The research treatment is adding feed additives (UB Feed) which are composed of natural ingredients, include amino acids, multivitamins, balanced micro minerals, acidifiers, probiotics, and phytobiotics. Research treatment was P1 (100% commercial complete feed), P2 (100% mixed feed), and P3 (100% mixed feed + 0.4% feed additive UB Feed). The research variables were egg production (percentage), cholesterol content (mg/100 mg) and protein content of egg yolk (g/100 g), and protein content of albumin (g/100 g). Based on the research results, the addition of natural feed additives had a very significant effect (P<0.01) on the egg production and quality of Mojosari duck eggs. The addition of natural additive feeds in feed increased egg production, yellow protein content and egg albumin and reduced cholesterol content of egg yolk.

Effect of Moringa oleifera leaf powder in diets on laying hens performance, β-carotene, cholesterol, and minerals contents in egg yolk

The present study was designed to investigate the influence of Moringa oleifera on Laying Hens Performance, β-carotene, cholesterol, and minerals contents in egg yolk. Two hundred and forty 30 weeks of healthy laying hens with homogeneous body weight in a complete randomized design with four treatments and 6 replications. Laying hens were randomly divided into four groups: M0: diets without administration of Moringa oleifera leaves, M1: diets with 2% Moringa oleifera leaves; M2: diets with Moringa oleifera leaves 4%; and M3: diets with 6% Moringa oleifera leaves, respectively. Each treatment consisted of six replication cages with 10 birds randomly assigned to each cage. This study showed that administration of the Moringa leaves powder were increased significantly different on egg productions, egg mass, feed efficiencies, yolk color, shell thickness, Mg and Ca contents in eggshell, but not the efficiency of feed consumption. The administration of 2-6% Moringa leaves powder in diets results in significantly lower yolk cholesterol contents. It was concluded that supplementation of 4-6% Moringa leaves powder in diets, increased egg production, egg mass, feed efficiencies, yolk color, shell thickness, β-carotene, Mg and Ca contents in the yolk, but decreased yolk cholesterol contents in laying hens.

Effect Of Symbiotic Flour (Lactobacillus Sp. And FOS) To The Egg Quality And Performance Of Laying Hens

The research was to determine the effect of feeding symbiotic flour (Lactobacillus sp. and FOS) to the egg quality and performance of laying hens. The research was a completely randomized design with 5 treatments and 4 replicates. The materials used for this research were 100 laying hens (30 weeks old). The treatments used for the research were dietary feed consisted of T0 (basal feed), T1 (basal feed + 0.2% symbiotic), T2 (basal feed + 0.4% symbiotic), T3 (basal feed + 0.6% symbiotic), and T4 (basal feed+0.8% symbiotic). The observed parameters were performance (feed intake, hen day production, egg mass, feed conversion ratio, income over feed cost (IOFC)) and egg quality (haugh unit, albumin volume, egg yolk volume, egg yolk color, egg yolk cholesterol content). The data analysis was the analysis of variance (ANOVA) and continued by Duncan’s Multiple Range Test. The results showed that using the symbiotic flour (Lactobacillus sp. and FOS) in the feed has significant difference (P<0.05) on IOFC and egg yolk volume, while also had significantly difference (P<0.01) on performance (feed intake, egg mass, feed conversion ratio) and egg quality (albumin volume, egg yolk color, and cholesterol). The research concludes that the addition of 0.8% probiotic flour (Lactobacillus sp.) as feed additive showed the best results.

Dietary levels of methionine plus cystine and chelated copper on the chemical composition of eggs and yolk cholesterol of 49-week-old brown laying hens

The present study aims to evaluate the possible interactions of dietary levels of methionine plus cystine (Met + Cys) and organic copper (Cu) on the chemical composition of eggs, using 320 Hy-Line Brown hens at 49 weeks of age. Composition and deposition variables were evaluated in a 4 × 5 factorial arrangement, with total analysed levels of 18, 44, 71, and 99 mg kg-1 of Cu and 0.613, 0.631, 0.816, 0.918, and 0.955% Met + Cys. We allocated four replicate cages (four hens/cage) to each treatment group. Two eggs per plot were sampled to determine the chemical composition of albumen and yolk, based on natural and dry matter and on daily rates of deposition. An interaction effect of Met + Cys and Cu levels was observed for deposition rates of ash and Cu in the yolk, and the chemical composition of Ethereal Extract (EE) and ash in eggs, EE in albumen and Nitrogen, EE, and ash in the yolk. An isolated effect was observed for Met + Cys on egg chemical composition and on shell and yolk fractions, as well as on deposition rates of albumen N, EE, and ash, and yolk EE. The yolk cholesterol content increased by 18.17% with increasing Met + Cys in diets. In conclusion, the chemical composition of eggs varied with dietary Met + Cys and organic Cu concentrations. Dietary levels of Met + Cys determined the yolk cholesterol concentration in laying hens.

Dietary levels of methionine plus cystine and chelated copper on the chemical composition of eggs and yolk cholesterol of 49-week-old brown laying hens

The present study aims to evaluate the possible interactions of dietary levels of methionine plus cystine (Met + Cys) and organic copper (Cu) on the chemical composition of eggs, using 320 Hy-Line Brown hens at 49 weeks of age. Composition and deposition variables were evaluated in a 4 × 5 factorial arrangement, with total analysed levels of 18, 44, 71, and 99 mg kg-1 of Cu and 0.613, 0.631, 0.816, 0.918, and 0.955% Met + Cys. We allocated four replicate cages (four hens/cage) to each treatment group. Two eggs per plot were sampled to determine the chemical composition of albumen and yolk, based on natural and dry matter and on daily rates of deposition. An interaction effect of Met + Cys and Cu levels was observed for deposition rates of ash and Cu in the yolk, and the chemical composition of Ethereal Extract (EE) and ash in eggs, EE in albumen and Nitrogen, EE, and ash in the yolk. An isolated effect was observed for Met + Cys on egg chemical composition and on shell and yolk fractions, as well as on deposition rates of albumen N, EE, and ash, and yolk EE. The yolk cholesterol content increased by 18.17% with increasing Met + Cys in diets. In conclusion, the chemical composition of eggs varied with dietary Met + Cys and organic Cu concentrations. Dietary levels of Met + Cys determined the yolk cholesterol concentration in laying hens.

Dietary levels of methionine plus cystine and chelated copper on the chemical composition of eggs and yolk cholesterol of 49-week-old brown laying hens

The present study aims to evaluate the possible interactions of dietary levels of methionine plus cystine (Met + Cys) and organic copper (Cu) on the chemical composition of eggs, using 320 Hy-Line Brown hens at 49 weeks of age. Composition and deposition variables were evaluated in a 4 × 5 factorial arrangement, with total analysed levels of 18, 44, 71, and 99 mg kg-1 of Cu and 0.613, 0.631, 0.816, 0.918, and 0.955% Met + Cys. We allocated four replicate cages (four hens/cage) to each treatment group. Two eggs per plot were sampled to determine the chemical composition of albumen and yolk, based on natural and dry matter and on daily rates of deposition. An interaction effect of Met + Cys and Cu levels was observed for deposition rates of ash and Cu in the yolk, and the chemical composition of Ethereal Extract (EE) and ash in eggs, EE in albumen and Nitrogen, EE, and ash in the yolk. An isolated effect was observed for Met + Cys on egg chemical composition and on shell and yolk fractions, as well as on deposition rates of albumen N, EE, and ash, and yolk EE. The yolk cholesterol content increased by 18.17% with increasing Met + Cys in diets. In conclusion, the chemical composition of eggs varied with dietary Met + Cys and organic Cu concentrations. Dietary levels of Met + Cys determined the yolk cholesterol concentration in laying hens.

The Effect of Wheat Bran Dietary Fibre on Cholesterol Content of Egg Yolk Laying Ducks

To determine the influence of level of wheat bran supplementation on production performance, and egg yolk cholesterol traits of laying ducks, 48 laying ducks (40-week-old) were randomly assigned into four groups with 4 replications of 3 birds each. Treatment 1 ducks were received the control diet without wheat bran contained 17,21 % CP and 2917 kkal ME/kg. Treatment 2,3 and 4 ducks were received the basal diet supplemented with 10,20 and 30% wheat bran for 8-weeks. Results showed that dietary supplementation of wheat bran had no effect (P>0.05) on laying ducks egg production and feed egg ratio over the entire feeding period. Yolk cholesterol content was lower (P<0.05) in all wheat bran supplementation at one day after treatment. There were decreased (P<0.05) contents of yolk cholesterol compared to ducks fed control diet but no difference was exhibited in egg yolk cholesterol among diet with wheat bran supplementation. It could be concluded that wheat bran supplementation could lower an egg yolk cholesterol levels and improve the egg quality in laying ducks.

Comparison of egg quality, yolk cholesterol and fatty acid contents of chicken, quail, partridge and pheasant eggs

This experiment was conducted to compare the cholesterol concentrations of yolk and some internal and external quality chicken, quail, partridge and pheasant eggs. Chickens, quails and partridges are housed in cages and pheasants are housed floor pens. Egg quality traits were determined for 20 eggs per poultry species. Egg weight, egg shape index, eggshell strength, albumen ratio, yolk ratio, yolk index, albumen pH, yolk pH, shell ratio, albumen and yolk color characteristics were examined as egg quality analyzes. Ten eggs from each species wereused to determine total cholesterol and triglyceride levels of yolks. The highest egg shape index and eggshell strength values were obtained in the pheasant and chicken eggs. The lowest yolk ratio value was obtained in hen eggs. The shell ratio and yolk index of partridge eggs were higher than the other species. Chicken egg had a lower proportion of cholesterol compared with other species. Partridge eggs have a lighter yolk color than other species. There was no statistically significant difference between the other species in terms of egg yolk cholesterol content, while the lowest egg yolk cholesterol value was detected in chicken eggs.