Dietary cholesterol effects on plasma and yolk cholesterol fractions in selected lines of Japanese quail

Grape Pomace: Agrifood By-Product with Potential to Enhance Performance, Yolk Quality, Antioxidant Capacity, and Eggshell Ultrastructure in Laying Hens

Grape pomace (GP) is an industrial by-product of grape juice making and is commonly discarded as a waste product, even with its large quantity of phytochemicals. Thus, the objectives of this trial were to examine the effects of graded dietary GP on laying rate, egg quality, yolk lipid profile, oxidative stability, shell quality and ultrastructure, and serum biochemistry. Two hundred 35-week-old laying hens were allocated to four dietary treatments with ten replicates each. Four diets were formulated by mixing a standard basal diet with GP at 0 g/kg (control), 30 g/kg (GP_3%), 60 g/kg (GP_6%), and 90 g/kg (GP_9%). Egg production percent, egg weight, and egg mass were linearly improved (p < 0.01) due to adding GP to the diets of laying hens. Eggs obtained from laying hens fed with GP diets had (p < 0.01; linear, p < 0.01) greater Haugh units, yolk color, albumen index, and yolk index than those of the control. The GP_9% group had the greatest values (p < 0.05) for shell weight, thickness, and breaking strength. Electron microscopy scanning of eggshells indicated that the incremental dietary level of GP linearly augmented the thickness of the palisade layer but reduced both the mammillary layer and mammillary knob width (p < 0.01). Improved tibia-breaking strength and ash content were shown (p < 0.05) in the GP-fed laying hens. The dietary addition of GP by up to 90 g/kg linearly (p < 0.01) mitigated lipid oxidation and improved the antioxidant capacity in both the serum and stored eggs. A reduction in the percentages of saturated fatty acids was observed, while the contents of monounsaturated fatty acids, polyunsaturated fatty acids, and n-3 fatty acids were augmented because of increasing dietary GP levels (p < 0.001). Additionally, the eggs obtained from laying hens fed on the GP_6% and GP_9% had lower yolk cholesterol content (p < 0.001); this effect was confirmed by linear and quadratic responses (p < 0.001). Laying hens on GP diets had lower (p < 0.01) serum hepatic enzymes, cholesterol, triglycerides, and low-density lipoprotein but greater high-density lipoprotein compared to the control. To sum up, the addition of GP in the layers' diets by up to 90 g/kg increased laying performance, enriched the yolk with beneficial fatty acids, enhanced antioxidant potential in yolk lipids, and improved shell quality and ultrastructure.

Unraveling the Potential of Orange Pulp for Improving Laying Rate, Egg Quality, Oxidative Stability, Fatty Acids Composition, and Reproductive Tract Morphology of Laying Hens

The current study aimed to demonstrate the effects of dietary dried orange pulp (DOP) on the laying performance, egg quality, antioxidant status, yolk fatty acid composition, serum biochemistry, and reproductive tract morphology of laying hens. A total of 200 Lohman Brown Lite laying hens were randomly allotted into 4 dietary treatments with 10 replicates each. The experimental treatment groups were the control group, a basal diet containing 50 g DOP/kg feed (DOP_5%), a basal diet containing 70 g DOP/kg feed (DOP_7%), and a basal diet containing 100 g DOP/kg feed (DOP_10%). Data were statistically analyzed by one-way ANOVA following a completely randomized design, and the incremental levels of dietary DOP were tested by orthogonal polynomial contrasts. The body weight gain, feed intake, egg production%, egg weight, egg mass, and feed conversion ratio of laying hens fed the DOP_7% and DOP_10% diets were greater (p < 0.01) than those fed the control diet. Eggs obtained from the DOP_7% and DOP_10% groups had a heavier shell weight% and shell thickness, as well as a greater yolk color score (p < 0.01; linear, p < 0.01). Dietary DOP improved the egg yolk concentrations of PUFA, n-3 PUFA, and n-6 PUFA (linear, p < 0.001; quadratic, p < 0.05), whereas the content of SFA was reduced (p < 0.001; linear, p < 0.001). The egg yolk cholesterol and triglyceride levels were linearly decreased (p < 0.001) with the inclusion of DOP in the diets of hens. After storage for 40 days, the malondialdehyde (MDA) contents in the egg yolk were reduced, whereas the glutathione peroxidase content was increased (p < 0.01) due to dietary DOP. The DOP_7% and DOP_10% hens had an obvious reduction in the levels of serum total lipids, total cholesterol, triglycerides, low-density lipoprotein, and MDA, whereas high-density lipoprotein and GPx levels were increased (p < 0.01) compared with those fed the control diet. The relative weights of the ovary, oviduct, uterus, and follicle of hens receiving diets containing 7% and 10% DOP were heavier (p < 0.01) than those of the control hens. Moreover, the number of large yellow follicles was increased (p < 0.001; linear, p < 0.001) in the hens-fed diets containing 7% and 10% DOP. In conclusion, dietary DOP at up to 100 g/kg of feed improves laying performance, health status, antioxidant capacity, egg nutritive value, and egg shelf life in laying hens.

Akkermansia muciniphila Enhances Egg Quality and the Lipid Profile of Egg Yolk by Improving Lipid Metabolism

Akkermansia muciniphila (A. muciniphila) has shown potential as a probiotic for the prevention and treatment of non-alcoholic fatty liver disease in both humans and mice. However, relatively little is known about the effects of A. muciniphila on lipid metabolism, productivity, and product quality in laying hens. In this study, we explored whether A. muciniphila supplementation could improve lipid metabolism and egg quality in laying hens and sought to identify the underlying mechanism. In the first experiment, 80 Hy-Line Brown laying hens were divided into four groups, one of which was fed a normal diet (control group), while the other three groups were administered a high-energy, low-protein diet to induce fatty liver hemorrhagic syndrome (FLHS). Among the three FLHS groups, one was treated with phosphate-buffered saline, one with live A. muciniphila, and one with pasteurized A. muciniphila. In the second experiment, 140 Hy-Line Brown laying hens were divided into two groups and respectively fed a basal diet supplemented or not with A. muciniphila lyophilized powder. The results showed that, in laying hens with FLHS, treatment with either live or pasteurized A. muciniphila efficiently decreased body weight, abdominal fat deposition, and lipid content in both serum and the liver; downregulated the mRNA expression of lipid synthesis-related genes and upregulated that of lipid transport-related genes in the liver; promoted the growth of short-chain fatty acids (SCFAs)-producing microorganisms and increased the cecal SCFAs content; and improved the yolk lipid profile. Additionally, the supplementation of lyophilized powder of A. muciniphila to aged laying hens reduced abdominal fat deposition and total cholesterol (TC) levels in both serum and the liver, suppressed the mRNA expression of cholesterol synthesis-related genes in the liver, reduced TC content in the yolk, increased eggshell thickness, and reshaped the composition of the gut microbiota. Collectively, our findings demonstrated that A. muciniphila can modulate lipid metabolism, thereby, promoting laying hen health as well as egg quality and nutritive value. Live, pasteurized, and lyophilized A. muciniphila preparations all have the potential for use as additives for improving laying hen production.

Production performance, egg quality, blood biochemical constituents, egg yolk lipid profile and lipid peroxidation of laying hens fed sugar beet pulp

The effect of including sugar beet pulp (SBP) in laying hen diets on performance, egg quality, blood chemistry and egg lipid peroxidation was studied. A total of 200 laying hens were randomly assigned into 4 groups and were offered diets containing SBP at the level of 0%, 3%, 5%, and 7%. The dietary inclusion of SBP linearly (P < 0.01) increased feed intake, egg production, egg weight and mass, and improved feed conversion ratio, yolk color core and Haugh unit. Eggs laid by hens receiving SBP had linearly (P < 0.01) greater protein and lower ether extract. Dietary inclusion of SBP linearly (P < 0.01) decreased egg yolk malondialdehyde, cholesterol, and triglyceride, while increased glutathione peroxidase. Laying hens fed SBP had lower (P < 0.01) serum total lipids, cholesterol, alanine aminotransferase, aspartate aminotransferase, and creatinine. Dietary inclusion of SBP could improve hen performance, health, egg quality, and egg shelf life.

Physiological performance of quails that underwent dietary and pharmacological manipulation of cholesterol

The present work evaluated whether dietary and pharmacological interference on cholesterol synthesis were capable of inducing alterations in blood and yolk cholesterol levels and the secretion of corticosterone metabolites. Forty-five 40-day-old quails were divided into three experimental groups: vegetal fat diet, 2% beef fat (tallow) diet and vegetal fat diet with simvastatin administration (3.13 mg/kg/day). During all experiments, the animal weights and food consumption were recorded and blood and faecal samples (days 0, 15, 30, 45 and 60), as well as eggs (days 30, 45 and 60), were collected. Analysis of serum and yolk cholesterol was performed and faecal corticosterone levels were measured. No differences were observed on blood cholesterol or faecal corticosterone between all treatments, despite a tendency of increased cholesterol in the group with the animal fat diet. However, quails submitted to an animal fat diet displayed an increase in yolk cholesterol at day 30 of the treatment and the egg yolks of quails treated with simvastatin exhibited a decrease in cholesterol content by the end of the treatment at 60 days. These results improved the knowledge regarding the physiology of quails and offered support to other studies concerning the consequences of the pharmacological treatment and the dietary manipulation of cholesterol levels.

Effect of supplementation of different boron and copper levels to layer diets on performance, egg yolk and plasma cholesterol

PROCEDURE

This study was conducted to determine the effects of supplementation of different levels boron and copper on performance, lipids in yolk and plasma contains in layer diets. In this trial a total of 320 layer chicken (26 weeks old age) was randomly distributed in 16 experimental groups. In each experiment group were consist at 5 replicates, and in each replicates there were 4 birds. During the 16 weeks experiment period, birds were fed with 16 experimental diets. Experimental diets were consisting of all possible combination of 4 levels of added boron (0, 60, 120 and 240 mg/kg) and 4 levels of added copper (0, 75, 150 and 300 mg/kg) to the basal ration.

RESULTS

Effect of treatments on body weight change and plasma glucose levels were not significant. However, added boron and copper had a significant effect on plasma high-density lipoprotein cholesterol fraction. While added boron had a significant adverse effect on performance parameters, added copper had a significant positive effect on the same parameters. Yolk lipid contents were increased by addition of boron to the ration. However, yolk lipid contents were decreased by addition of copper to the ration. Plasma lipid contents were also decreased by addition of copper and boron in the ration.

CONCLUSION

Results of the present study showed that laying hens from 26 to 42 weeks of age should be fed with 60 mg/kg boron and 150 mg/kg copper supplementation in the diet.

Effect of dietary Rhodobacter capsulatus on lipid fractions and egg-yolk fatty acid composition in laying hens

The present study was conducted to investigate the effect of dietary Rhodobacter capsulatus on lipid fractions and egg-yolk fatty acid composition in laying hens. Thirty-six laying hens (30 weeks old) were randomly assigned into two dietary groups fed diets with (0.04%) or without (control) R. capsulatus for a 60-day feeding trial. Dietary R. capsulatus decreased (p < 0.05) serum and hepatic cholesterol and increased (p < 0.05) the excreta cholesterol, and resultant lower (p < 0.05) cholesterol contents in egg yolk. The concentration of polyunsaturated fatty acids (PUFA) and ratio to saturated fatty acids in egg yolk was improved (p < 0.05) by dietary R. capsulatus. The concentration of hepatic bile acid was increased (p < 0.05) and excreta bile acid was decreased (p < 0.01) in the laying hens fed R. capsulatus diet. The incorporation of 1-(14) C-palmitic acid into hepatic lipids and lipid fractions was increased (p < 0.05) in laying hens fed R. capsulatus diet. Moreover, dietary R. capsulatus did not appear to cause any adverse effects on laying hen performances. Therefore, dietary supplementation of R. capsulatus in layer diets may be a feasible means of producing eggs with lower cholesterol and higher PUFA contents for health conscious consumers.

Hypocholesterolemic effect of karaya saponin in Japanese laying quails (Coturnix coturnix japonica)

The effect of karaya saponin supplementation on the serum and egg yolk cholesterol and fatty acid composition in egg yolk were investigated in Japanese quails. A total of 80 Japanese quails aged 5 weeks were equally divided into four groups of 20. Four levels (0, 25, 50 and 75 mg/kg feed) of karaya saponin were included in the basal diet and experiment was lasted for 6 weeks. The cholesterol fractions in the egg yolk and serum were measured by enzymatic assay, and the fatty acid composition in egg yolk was determined by gas chromatography. The results revealed that the supplementation of 75 mg/kg karaya saponin significantly reduced (p < 0.05) cholesterol and triglycerides concentration in serum and egg yolk. High-density lipoprotein-cholesterol was increased, low-density lipoprotein-cholesterol and the atherogenic index were decreased (p < 0.05) by the dietary supplementations. Hepatic cholesterol was reduced (p < 0.05) by the 25 mg/kg karaya saponin. A higher degree of yolk colour was improved (p < 0.05) when 75 mg/kg saponin was supplemented in the diet. The concentration of polyunsaturated fatty acids (PUFA) in egg yolk was increased (p < 0.05) in a dose-dependent manner in quails fed the supplemented diet than the control diet. The ratio of PUFA to saturated fatty acids in egg yolk was improved (p < 0.05) by 75 mg/kg feed karaya saponin-supplemented diet. Therefore, the dietary supplementation of 75 mg/kg karaya saponin may be a feasible means of producing quail eggs with lower cholesterol and higher PUFA content for health conscious consumers.

Fatty acid profile and cholesterol content of egg yolk from chickens fed diets supplemented with purslane (Portulaca oleracea L.)

BACKGROUND

The aim of the present study was to evaluate the effects of purslane on egg production, egg weight, feed efficiency, yolk fatty acid composition, and egg cholesterol content in laying hens.

MATERIAL AND METHODS

Sixty 80-week-old layers were allocated randomly to receive diets supplemented with 0 (control), 10 g kg(-1) or 20 g kg(-1) dried purslane for 84 days. Egg weights and egg production in the groups were recorded daily, whereas feed intake was measured weekly.

RESULTS

Diet supplemented with 20 g kg(-1) purslane significantly decreased body weight of the chickens compared to the control. Inclusion of purslane at the level of 10 g kg(-1) or 20 g kg(-1) into the diet significantly (P < 0.05) improved egg weight compared to the control. Chickens fed the diet including 20 g kg(-1) purslane had a significantly (P < 0.05) higher egg production and improved feed efficiency compared to the control. Cholesterol content of eggs from the hens fed 0, 10 or 20 g kg(-1) did not differ and was 10.45, 9.51 or 9.51 mg g(-1) dried egg yolk, respectively. Inclusion of purslane at the level of 20 g kg(-1) into the diet significantly (P < 0.05) increased omega-3 fatty acids such as C18:3(omega-3) and C22:6(omega-3). The ratio of omega-6 to omega-3 also was significantly (P < 0.05) lower in the eggs from chickens fed 10 g kg(-1) or 20 g kg(-1) purslane supplemented diets compared to the control.

CONCLUSION

This study showed that adding dried purslane to the diet of laying hens significantly increased egg production and egg weights although there was no reduction in the egg cholesterol concentration. This study also showed that inclusion of purslane into diet enriched eggs with omega-3 fatty acids and decreased the ratio of omega-6/omega-3 in the yolk.

Effects of dietary copper on production and egg cholesterol content in laying hens

1. This experiment was carried out to determine the effects of diets supplemented with different amounts of copper on egg production, food intake, food conversion ratio, egg weight, damaged egg ratio, specific gravity, mortality and cholesterol concentration in yolk. The experiment lasted 90 d and 400 Hisex-Brown hens, aged 27 weeks at the start of the study, were used. 2. There were no statistically significant effects of supplementary copper on egg production, food intake or food conversion efficiency. 3. There were no statistically significant differences between the groups in terms of damaged eggs, egg weight, specific gravity and live weight. 4. At the end of the experiment, the lowest yolk cholesterol concentrations were obtained in the 150 kg/kg copper group and the greatest concentrations were in the control group. 5. Consequently, the use of supplementary copper to provide 150 kg/kg in poultry diets was concluded to decrease yolk cholesterol concentrations without any effect on production performance.

Effect of Alfalfa Meal in diets of laying quails on performance, egg quality and some serum parameters

This study was conducted to investigate the effects of increasing levels of alfalfa meal in the diet of laying quails on egg production, feed consumption, feed efficiency, egg quality, egg yolk cholesterol and selected serum parameters. In this study, 192, 10-week old quails (Coturnix coturnix japonica) were evenly distributed to four groups with four replicates of 12 quails each. The control group was fed a basal diet containing 0% alfalfa meal and the remaining groups received 3, 6 or 9% alfalfa meal for 12 weeks. Live weight, feed consumption, and egg production were recorded and feed efficiency were calculated. Eggs were examined for interior and exterior quality and egg yolk cholesterol content. At the end of the experiment, blood samples were collected and sera were analysed for serum Ca, inorganic P (P(i)), Mg, triglycerides and total cholesterol. Any level of alfalfa meal had no effect on live weight, egg production, feed consumption, feed efficiency, egg weight, and egg yolk index. Six percent and 9% alfalfa meal increased specific gravity of whole egg and eggshell thickness as well as serum P(i) levels. Nine percent alfalfa meal reduced serum triglycerides, total cholesterol levels and egg yolk cholesterol content. The results of this experiment indicated that addition of 9% alfalfa meal into the laying quail diet may improve eggshell quality and reduced serum triglycerides and serum and egg yolk cholesterol without any adverse effect on performance.

Effect of red mold rice supplements on serum and egg yolk cholesterol levels of laying hens

Monacolin K is a secondary metabolite of Monascus species and reduces cholesterol levels. This research focuses on the effect of adding red mold rice to hens' diet on cholesterol level in egg yolk and on cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) levels in serum. Forty-eight Hy-line laying hens of 48 weeks of age were studied by dividing them into four groups. Except for the control group, the feed for three other groups contained 2.0, 5.0, and 8.0% red mold rice (monacolin K concentrations were 0.0145, 0.035, and 0.056%, respectively). The experiment lasted 6 weeks. During this period, egg weight and egg production were recorded every day, and cholesterol, triglyceride, HDL, and LDL in serum were measured weekly as well. The result showed that the cholesterol in eggs produced by experimental groups was lower than that of the control group (0%, 194.14 +/- 8.30; 2%, 167.17 +/- 4.34; 5%, 168.93 +/- 9.38; 8%, 183.02 +/- 7.63 mg/egg; p < 0.05), and the triglyceride (0%, 1494 +/- 178; 2%, 1280 +/- 174; 5%, 1189 +/- 248; 8%, 1381 +/- 218 mg/dL; p < 0.05) and LDL levels (0%, 36.81 +/- 5.53; 2%, 32.25 +/- 7.93; 5%, 30.06 +/- 4.39; 8%, 28.81 +/- 4.16 mg/dL; p < 0.05) were also significantly lowered in the experimental groups. However, the HDL level did not show significant change for either control or experimental groups (0%, 36.06 +/- 3.96; 2%, 36.25 +/- 5.39; 5%, 33.13 +/- 3.68; 8%, 31.44 +/- 4.29 mg/dL; p > 0.05). Besides, the addition of red mold rice also helps to inhibit production of malondialdehyde (MDA) in serum lipid oxidation (0%, 27.42 +/- 0.53; 2%, 25.62 +/- 0.76; 5%, 24.35 +/- 0.59; 8%, 23.63 +/- 0.48 microM; p < 0.05).

Effect of different dietary levels of Yucca schidigera powder on the performance, blood parameters and egg yolk cholesterol of laying quails

A total of 135 laying quails (Coturnix coturnix japonica), 9 weeks old, were divided into three dietary treatment groups. Three replicates were assigned to each treatment group consisting of 15 birds per cage. The diet was supplemented with 0, 100 and 200 ppm Yucca schidigera powder and given ad libitum to the quails for a period of 14 weeks. Body weight, egg production, feed consumption and feed efficiency were not different due to dietary treatments among the groups. Increased egg weight was determined in the control group. Yucca powder supplementation decreased serum glucose, cholesterol triglyceride level in laying quails. Serum total protein concentration was not changed by dietary treatments but albumin level was decreased in quails fed 100 ppm yucca powder. Egg yolk cholesterol concentration was not significantly different among the groups but tended to decline (11.5%) as a result of yucca supplementation. Red Blood Cell (RBC) and White Blood Cell (WBC) counts, packed cell volume (PCV), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) were not affected by supplementation of yucca powder. However, haemoglobin (HB) concentration was slightly increased and mean corpuscular haemoglobin concentration (MCHC) was significantly increased by 200 ppm yucca powder supplementation to the diet.

Effects of zinc and vitamin A supplements on plasma levels of thyroid hormones, cholesterol, glucose and egg yolk cholesterol of laying hens

The effects of zinc and vitamin A supplementation to the diet on some blood metabolites were evaluated in Hisex brown laying hens from 56 weeks to 68 weeks of age. A total of 130 birds were divided into two main groups according to vitamin A treatment (0 and 3.44 mg retinyl acetate kg(-1) feed, respectively), each consisting of 65 hens. Hens in both of the main groups were then divided into five zinc treatment groups (0, 25, 50, 100 and 200 mg zinc kg diet(-1) respectively) of 13 hens each. It was observed that plasma T4, T3 and total cholesterol levels were affected by only zinc supplementation. While 100 and 200 mg Zn kg(-1) decreased plasma T4 level compared to control value, plasma T3 level was reduced by 100 mg Zn kg(-1) compared to groups fed less Zn. Adding 50 and 200 mg Zn kg(-1) to the diet increased plasma total cholesterol level in the birds compared to other groups. Vitamin A, zinc, and their interaction did not influence the concentration of plasma high-density lipoprotein (HDL)-cholesterol, glucose and egg yolk cholesterol in laying hens.

Epitopes for chicken monoclonal antibodies in spleens of selected Japanese quail lines

A line of Japanese quail selected for high plasma cholesterol is highly susceptible to diet-induced atherosclerosis. Lymphocyte epitopes recognized by mouse anti-chicken monoclonal antibodies (c-mAb), TCR-1, TCR-2, TCR-3. CD-3, CD-4, CD-8, and BU-1a/b were reacted with spleens from quail selected for high (HL) and low (LL) plasma total cholesterol and their nonselected controls (CL). Cross reactivity to c-mAb and effect of line and gender were immunohistochemically evaluated. Chicken spleens were positive controls. Quail were immunologically stimulated with either sheep red blood cells (SRBC) or Brucella abortus 2 weeks before spleens were removed. Quail spleen epitopes of all lines recognized TCR-3 and CD-8 c-mAb, but no other c-mAb. Number of reacting cells and staining intensity to the TCR-3 c-mAb were greater in the HL than in the LL regardless of the stimulating Ag or dose used. For the CD-8 c-mAb, there were no differences among lines in birds receiving SRBC. In B. abortus-immunized birds, sex x line interactions indicated that males of the HL and CL had lower responses than females but LL males were not different than females. TCR-3 and CD8 c-mAb may be useful in studying immunological mechanisms for atherosclerosis in Japanese quail.