The Effects of Dietary Inclusion of Bilberry and Walnut Leaves in Laying Hens’ Diets on the Antioxidant Properties of Eggs

Influence of rosehip (Rosa canina L.) leaves as feed additive during first stage of laying hens on performances and egg quality characteristics

This study aimed to evaluate the effects of rosehip leaves (RL) supplementation on the production performances and egg quality of laying hens during the first stage of laying. For that, 90 Lohmann Brown Classic hens, aged 26 wk, were randomly assigned to 3 dietary treatments as follows: a control diet (RL0), an experimental diet containing 0.5% rosehip leaves (RL0.5), and an experimental diet containing 1% rosehip leaves (RL1). The laying hens were accommodated in an experimental hall with identical pens (3.96 m2), and controlled microclimate conditions. The dietary treatments were administered for a 6-wk experimental period (26-32 d of age). During this time, production performance of hens was recorded. To assess the impact of RL on egg weight and its components evolution, egg yolk and albumen color, and primary chemical composition of egg constituents were determined every 2 wk. The effect on egg yolk fatty acids profile was determined only at the end of the trial. The results showed that RL0.5 and RL1 dietary treatments significantly improved laying rate, feed conversion ratio and egg mass compared with RL0 group. A significant effect on egg weight and its components was observed only over time, showing that RL has no effect on these parameters. Significant changes in egg yolk coloration were observed over time, with significant increases in L*, a* and b* chromomeric parameters in both RL0.5 and RL1 compared to RL0. Significant alterations were obtained from the sum of egg yolk fatty acids. The RL1 egg yolk presented significantly higher n-3, and significantly lower n-6 fatty acids, compared with both RL0 and RL0.5. Further research is warranted to explore the long-term effects of rosehip leaf supplementation on laying hens performance and egg quality.

Comparative Effects on Using Bilberry Leaves in Broiler Diet Reared under Thermoneutral Conditions vs. Heat Stress on Performance, Health Status and Gut Microbiota

The study aims to investigate the impact of dietary bilberry leaves on the performance, health status, and gut microbiota of broilers reared in both thermoneutral conditions and under heat stress. Sixty Cobb 500 broiler chicks were divided into two groups (C-TN, BL-TN) and reared in thermoneutral conditions for the first trial. For the second trial, two other groups (C-HS and BL-HS) were reared in heat stress (32 °C), with 30 chickens in each group. The experimental diets were supplemented with 1% bilberry leaves compared to the control diets. The broilers fed a diet with bilberry leaves had lower levels of cholesterol compared to the control birds. At the end of the experiment, six broilers per group were slaughtered, and intestinal contents were collected for bacteriological analyses. The results revealed that bilberry leaves increased body weight and average daily feed intake in the BL-TN group compared to the C-HS group. However, the broilers fed a bilberry leaves diet and reared in heat stress had a significantly lower average daily feed intake and average daily weight gain than the C-TN group. Additionally, the number of staphylococci colonies decreased significantly in the group fed with a BL-supplemented diet and reared in TN compared to C-TN, while lactobacilli increased significantly in BL-TN compared to C-TN. In summary, bilberry leaves can be used as a natural supplement in a broiler's diet to regulate serum cholesterol in heat stress and maintain the health of intestinal microflora in thermoneutral conditions.

Exploring the Antioxidant Potential of Blackberry and Raspberry Leaves: Phytochemical Analysis, Scavenging Activity, and In Vitro Polyphenol Bioaccessibility

The goal of this research was nutritional evaluation through the phytochemical analysis of blackberry and raspberry leaves, the screening of their biological activity (antioxidant capacity and inhibition of lipid peroxidation), and the investigation of the effect of in vitro gastrointestinal digestion (GID) of blackberry and raspberry leaves on the bioaccessibility of polyphenol subclasses. The concentrations of the analyzed liposoluble antioxidants were higher (p < 0.05) in blackberry leaves compared to raspberry leaves, while a significant (p < 0.05) higher content of water-soluble antioxidants was registered in raspberry leaves (with a total polyphenol content of 26.2 mg GAE/g DW of which flavonoids accounted for 10.6 mg/g DW). Blackberry leaves had the highest antioxidant capacity inhibition of the superoxide radicals (O2•-), while raspberry leaves registered the highest inhibition of hydroxyl radicals (•OH), suggesting a high biological potency in scavenging-free radicals under in vitro systems. The maximum inhibition percentage of lipid peroxidation was obtained for blackberry leaves (24.86% compared to 4.37% in raspberry leaves), suggesting its potential to limit oxidative reactions. Simulated in vitro digestion showed that hydroxybenzoic acids registered the highest bioaccessibility index in the intestinal phase of both types of leaves, with gallic acid being one of the most bioaccessible phenolics. The outcomes of this investigation reveal that the most significant release of phenolic compounds from blackberry and raspberry leaves occurs either during or after the gastric phase. Knowledge about the bioaccessibility and stability of polyphenol compounds during digestion can provide significant insights into the bioavailability of these molecules and the possible effectiveness of plant metabolites for human health.

n-3 PUFA Enriched Eggs as a Source of Valuable Bioactive Substances

This research elaborates the process of enriching table eggs with n-3 polyunsaturated fatty acids (n-3 PUFA) and presents the effect of such enriched eggs on human health. The experiment was performed on 480 TETRA SL laying hens divided into three groups. Feeding mixtures contained 5% of oils (K = soybean oil, P1 = 3.5% linseed oil + 1.5% fish oil, P2 = 3% linseed oil + 2% fish oil). Referring to the content of α-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), eggs of P1 and P2 groups were significantly richer in n-3 PUFA than eggs of the control group (p = 0.001). Atherogenic (AI), thrombogenic (TI), and hypo/hypercholesterolemic (HHI) indexes of egg yolks were more favourable in enriched eggs than in conventional eggs. Fatty acid profiles in the blood of examinees that consumed conventional and enriched eggs (treatments K and P1, respectively) differed significantly in total saturated fatty acids (ΣSFA) (p = 0.041) and in the content of ALA (p = 0.010). The consumption of n-3 PUFA-enriched eggs lowered the Σn-6 PUFA/Σn-3 PUFA ratio in the examinees' blood serum (27%) and had a favourable effect on some blood biochemical indicators. This research confirmed the assumption that the use of a combination of fish and linseed oil in mixtures for laying hens in an amount of up to 5% will increase the content of omega-3 in table eggs, but it was not confirmed that the consumption of these eggs in a short period of time (21 days) has a positive effect on human health.

Mitigation of heat stress effects on laying hens' performances, egg quality, and some blood parameters by adding dietary zinc-enriched yeasts, parsley, and their combination

Objective

Finding natural, handy and efficient nutritional solutions to prevent and mitigate negative effects caused by environmental heat stress and to be applied to large-scale laying hen industry.

Research design

A 3-weeks trial was conducted on 128 laying hens TETRA-SL LL (50 weeks of age) housed in 8 cages/group, 4 laying hens/cage, 32 laying hens/group, under heat stress conditions (34±1°C). The basal diet on corn and soybean meal was formulated to be isocaloric and isonitrogenic. Compared to Control group diet (C), experimental groups E1 included 1% zinc-enriched yeast; E2 included 2% parsley and E3 included 1% zinc-enriched yeast combined with 2% parsley to minimize the heat stress effects.

Methods

The parsley and the zinc-enriched yeast were analysed for their chemical composition, total polyphenols, antioxidant capacity, minerals, vitamin E and incorporated into the ration structure. Production parameters, egg quality, biochemical and haematological profiles of blood samples were analysed during the trial.

Results

A statistically significant (p < 0.05) average egg weight was noticed on E2 and E3 compared to Control group, and also during the 1st week compared to the 2nd and the 3rd experimental weeks. Average daily feed intake values were highly significant (p < 0.001) on E3 group compared to C, E1, E2, and on the 2nd week compared to the 3rd experimental week (p < 0.021). Feed conversion rate was highly significant (p < 0.001) during the 2nd and the 3rd experimental weeks compared to the 1st week. The average daily egg production was highly significant (p < 0.001) within 1st week compared to the 2nd and 3rd weeks. A highly significant (p < 0.001) yolk coloration was noticed on E2 and E3 groups. The malondialdehyde (MDA) concentration decreased significantly (p < 0.05) to all experimental groups compared to Control group during the 14th and 28th days of storage.

Conclusion

These findings suggest that the two ingredients minimized the heat stress effects on production performance parameters with a demonstrated antioxidant capacity role by delaying the lipid peroxidation during different storage time periods.

Antioxidant Properties of Cranberry Leaves and Walnut Meal and Their Effect on Nutritional Quality and Oxidative Stability of Broiler Breast Meat

Dietary sources of bioactive compounds in animal diets, are the natural way to produce animal food products with improved nutritional quality. The present study aimed to test the hypothesis of a synergistic effect of bioactive compounds of cranberry leaf powder and walnut meal on the nutritional quality and antioxidant compounds of broiler meat. An experiment was conducted on 160 COBB 500 broiler chickens, housed in an experimental hall with permanent wood shave litter in boxes of 3 m². The six dietary treatments were based on corn and soybean meal; three experimental groups were fed diets supplemented with cranberry leaves (CLs) with three inclusion rates (0% in the control group and CL 1% and CL 2%); two experimental groups were fed diets supplemented with walnut meal (WM) with two inclusion rates (0% and WM 6%); and two groups were fed diets with a combination of the selected supplements (CL 1% WM 6% and CL 2% WM 6%). The results show that the experimental groups registered higher concentrations of copper and iron compared with the control group. An antagonist effect was noticed on lipophilic compounds, and the lutein and zeaxanthin concentrations presented a dose-dependent increasing effect under CL influence, while vitamin E concentrations decreased in the same manner. The dietary WM positively influenced vitamin E deposits on breast tissue. The dietary supplements did not produce any effect on the primary oxidation products, but the secondary products were influenced, and the maximum effect on the TBARS values were recorded for the dietary combination of CL 1% and WM 6%.

Yolk Fatty Acid Content, Lipid Health Indices, and Oxidative Stability in Eggs of Slow-Growing Sasso Chickens Fed on Flaxseed Supplemented with Plant Polyphenol Extracts

Previous attempts to increase the level of flaxseed in hens' diet for the production of n-3 polyunsaturated fatty acids (n-3 PUFAs)-enriched eggs have been commonly associated with undesirable effects on production efficiency, lipid health indices, and oxidative stability of eggs, requiring adequate research attention. This study investigated the effects of feeding a moderate level of flaxseed (FS) and plant polyphenol extracts (PPEs) on fatty acid content, oxidative stability, and lipid health indices in eggs of slow-growing Sasso T451A laying hens. One hundred and five hens were assigned to five groups (seven replicates of three) and fed on FS (75 g flaxseed and no antioxidants), VE8 (75 g flaxseed and 800 mg vitamin E), TS8 (75 g flaxseed and 800 mg Thymus schimperi), DA8 (75 g flaxseed and 800 mg Dodonaea angustifolia), and CD8 (75 g flaxseed and 800 mg Curcuma domestica) extract per kg diets. The egg yolk content of eicosapentaenoic acid (EPA, C20:5 n-3) in the DA8, TS8, and CD8 diets and docosahexaenoic acid (DHA, C22:6 n-3) in TS8 and CD8 diets significantly (p < 0.05) increased compared with the FS diet. The FS diet significantly increased the malondialdehyde (MDA) content in egg yolks, whereas the TS8 diet decreased it by 67% (p < 0.05). Little difference was observed in yolk fatty acid content between cooked and raw eggs. Production of n-3 PUFA-enriched eggs with favorable lipid health indices was possible through inclusion of PPEs extracted from local plant species grown in Ethiopia and a moderate dose of flaxseed in the diet of laying hens.

Effect of purple corn extract on performance, antioxidant activity, egg quality, egg amino acid, and fatty acid profiles of laying hen

The objective of this study was to investigate the effects of anthocyanin-rich purple corn extract (PCE) on performance, antioxidant potential, egg quality, egg amino acid and fatty acid profiles of laying hens during the late laying period. A total of 360 88-wk-old laying hens were randomly divided into 4 groups, and fed a basal diet (CON) or a basal diet supplemented with 120 (LP), 240 (MP), and 360 mg/kg (HP) PCE, respectively. No significant difference (P > 0.05) was observed in the ADFI or average egg weight among the groups. However, the mean feed to egg ratio was quadratically decreased (P < 0.05) in the LP and HP treatments. The mean TAC was linearly and quadratically increased (P < 0.05) in all PCE supplemented treatments. The mean SOD was linearly and quadratically increased (P < 0.05) in the HP treatment compared with CON and MP groups. The GPX was linearly and quadratically lower in the HP treatment compared to the CON and LP groups. Differently, the MDA was linearly and quadratically lower (P < 0.05) in the PCE treatments compared with the CON. The eggshell thickness value in MP and HP treatments were linearly and quadratically higher (P < 0.05) than that of the CON and LP groups. Hens fed PCE was linearly and quadratically increased (P < 0.05) most individual amino acids, essential amino acid and umami amino acid profiles in egg. The PCE treatments showed linearly and quadratic (P < 0.05) effect on the myristoleate, heptadecenoic acid, elaidic acid, eicosenoic acid, heneicosanoic acid, and eicosatrienoic acid concentrations. Moreover, dietary supplementation of PCE was quadratically increased egg stearic acid, oleic acid, arachidic acid, linolenic acid methyl ester, arachidonic acid, diphenylamine, docosahexaenoic acid, monounsaturated fatty acid, and polyunsaturated fatty acid compared to the CON. Therefore, dietary anthocyanin-rich PCE can enhance plasma antioxidant potential, is beneficial to egg production, and improves amino acids and fatty acids in hen eggs during the late laying period.

Effects of Supplementing Sea Buckthorn Leaves (Hippophae rhamnoides L.) and Chromium (III) in Broiler Diet on the Nutritional Quality and Lipid Oxidative Stability of Meat

Nowadays, the consumer trend towards healthier food choices is unquestionable. Meat products enriched with nutrients, such as polyunsaturated fatty acids and antioxidants, are gaining much more interest among consumers. However, products are susceptible to quality deterioration and a short shelf-life of meat through lipid oxidation due to the lack of antioxidants in the meat. In this regard, the efficacy of dietary sea buckthorn leaves (Hippophaë rhamnoides L.) together with Chromium on the nutritional quality of meat and lipid oxidative stability was investigated. An experiment (28 days long) was carried out on 90 Cobb 500 chickens assigned into three treatments: a control treatment based on corn and soybean meal, without Chromium (T0) and two treatments supplemented either with 0.00002% Chromium (T1) or with 0.00002% Chromium and 2% sea buckthorn leaves (T2). Dietary supplementation of SBL and Cr improved the PUFA/MUFA ratio, DHA concentration and decreased the n-6/n-3 ratio compared to the other treatments. Moreover, the breast and thigh meat belonging to T1 and T2 treatments showed a higher concentration of lutein and zeaxanthin, Fe and Zn and expressed a higher antioxidant capacity compared to those from T0. Furthermore, n-6 and n-3 PUFA deposited preferentially in the thigh meat rather than in the breast meat. The results from the study showed that dietary SBL and Cr significantly improved the fatty acid pattern and the oxidative stability of chicken breast meat, lowering the TBARS level after storage. In conclusion, SBL and Cr are promising dietary bioactive compounds with beneficial effects to obtain nutrient-enriched meat products.

Rosehip (Rosa canina L.) Meal as a Natural Antioxidant on Lipid and Protein Quality and Shelf-Life of Polyunsaturated Fatty Acids Enriched Eggs

Eggs are a common food of animal origin, inexpensive, and rich in bioactive substances with high biological value. Eggs enriched in polyunsaturated fatty acids (PUFA) are extremely desired by the progressive consumer. However, during storage, eggs undergo some physiochemical changes, which decrease their value. In this regard, the effect of dietary rosehip meal and flaxseed meal on hens’ egg quality characteristics, amino acids, fatty acids, health-related indices, antioxidant capacity, total polyphenols content, and shelf life was examined. For this study 120 Tetra SL laying hens, 29 weeks of age, were fed, for 4 weeks, three diets that included control (basal diet—RF0), basal diet + 1.5% rosehip and 7% flaxseed meal (RF1), and basal diet + 3% rosehip and 7% flaxseed meal (RF2). Productive performance of hens were recorded. The content of essential amino acids (EAA), antioxidant amino acids (AAA), and sulfur amino acids (SAA) was higher in RF1 and RF2, compared with RF0. Eggs belonging to the RF1 and RF2 groups had significantly (p < 0.05) higher content of n-3 PUFAs, especially linolenic and docosahexaenoic acids. Total antioxidant capacity and polyphenol content increased in both rosehip supplemented groups, but especially in RF2. Moreover, eggs from RF1 and RF2 groups maintained significantly higher egg quality parameters after storage for 14 and 28 days in the refrigerator (5 °C) and ambient temperature (21 °C), compared with those from the RF0 group. In the Haugh unit, yolk and albumen pH presented better values in RF1 and RF2 eggs compared to the RF0 eggs.

Determination of Optimum TBARS Conditions for Evaluation of Cow and Sheep Milk Oxidative Stability

Having a complex fatty acid profile, milk is the subject of several oxidation processes that are different to those in other food matrices. Considering this, is important to appreciate the degradation status of milk using rapid and simple methods to quantify the main degradation products. The aim of this study was to adapt a simple and rapid method for determination of milk oxidative stability and to quantify malondialdehyde, one of the lipid oxidation products. Four parameters (trichloroacetic acid concentration—TCA, antioxidant type, incubation time, and thiobarbituric acid—TBA concentration) were modified to establish the best experimental sequence. It was concluded that the relevant results were obtained by precipitating milk proteins using 20% TCA; incubating samples for 90 min with 0.8% TBA, without adding antioxidant; and registering absorbance at three different wavelengths (450, 495, and 532 nm). This method was successfully applied to cow and sheep milk samples and the absorbance values obtained provided information about degradation of fatty acids for both milk types. The Pearson correlation showed a positive relationship between the fatty acid profiles of milk samples and the absorbance values that characterized their oxidation pattern during storage.

Creeping Wood Sorrel and Chromium Picolinate Effect on the Nutritional Composition and Lipid Oxidative Stability of Broiler Meat

The study investigates the efficacy of Cr in broilers, aiming to evaluate the effects of Chromium picolinate (CrPic) in association with creeping wood sorrel powder (CWS) on the proximate composition, fatty acids profile, bioactive nutrients and lipid oxidative stability of broiler meat. A total of 120 Cobb 500 chickens were assigned into three treatments: a control diet (C) and two test diets, including 200 µg/kg diet CrPic (E1), and 200 µg/kg diet CrPic +10 g CWS/kg diet (E2). Dietary supplementation with Cr + CWS significantly improved the concentration of n − 3 polyunsaturated fatty acids (PUFAs), while its n − 6/n − 3 ratio decreased in comparison to the group receiving Cr and the conventional diet. The concentration of docosahexaenoic acid (DHA) significantly increased in the breast meat collected from the E2 group than that from the C group. Dietary administration of Cr and CWS improved lutein and zeaxanthin content, decreased Fe and Zn levels of the breast, and increased Zn deposition in the thigh samples. Malondialdehyde (MDA) concentration decreased more in the thigh meat of the supplemental groups (E1, E2) than in that from the C group. In conclusion, the current study suggests that Cr together with CWS can be a viable option as antioxidant sources for broiler diets, promoting the nutritional quality of meat.

Nutritional Composition and Bioactive Compounds of Basil, Thyme and Sage Plant Additives and Their Functionality on Broiler Thigh Meat Quality

Meat industries across the world are constantly focusing to find natural low-cost additives for the development of novel meat products to meet consumer demand for improving the health benefits. In this study, we investigated the chemical composition and the bioactive compounds of some herbal plants, namely basil, thyme, sage, and their functionality on broiler chicken thigh meat quality. Chemical composition, as well as total antioxidant activity, polyphenols, vitamin E lutein and zeaxanthin and the fatty acids of the plants, were analyzed. According to findings, total polyphenols was 21.53 mg gallic acid/g in basil, 31.73 mg gallic acid/g in thyme and 38.87 mg gallic acid/g in sage. The antioxidant capacity was 19.91 mM Trolox in basil, 54.09 mM Trolox in thyme and 54.09 mM Trolox in sage. Lutein and zeaxanthin from basil was 267.91 mg/kg, 535.79 mg/kg in thyme and 99.89 mg/kg, and vitamin E ranged from 291.71 mg/kg in basil to 379.37 mg/kg in thyme and 148.07 mg/kg in sage, respectively. After, we developed a trial on 120 unsexed broiler chickens (n = 30) which were separated into four groups with six replications of five chickens each: control (C); 1% basil (B); 1% thyme (T) and 1% sage (S). The B, T and S groups deposited significantly higher (p < 0.05) concentration of zinc, polyphenols, antioxidant capacity and vitamin E in meat samples compared with the C group. In the experimental groups, the proportion of total polyunsaturated fatty acids, the ratio of n-6 to n-3 fatty acids, and the ratio of polyunsaturated fatty acids to saturated fatty acids in the thigh muscles were significantly improved (p < 0.05). The tested plants exhibited a significant (p = 0.0007) hypocholesterolemic effect in the meat of the B (45.90 mg/g), T (41.60 mg/g) and S (48.80 mg/kg) experimental groups compared with the C (60.50 mg/g) group. These results support the application of the studied plants as natural sources of additives which could be effective in improving meat quality, from the human consumption perspective.

Effects of Linseed Meal and Carotenoids from Different Sources on Egg Characteristics, Yolk Fatty Acid and Carotenoid Profile and Lipid Peroxidation

The present study aimed to evaluate the effect of supplementing the diet of laying hens with linseed meal and carotenoids from different sources on egg characteristics, yolk fatty acid and carotenoid profile, and lipid peroxidation. A 4-week experiment was conducted on 168 Lohmann Brown layers (43 weeks of age), assigned to four dietary treatments (42 hens/group; 21 replicate/groups with 2 birds/pen) consisting of a control diet (C) and three diets simultaneously supplemented with 6% linseed meal and 2% dried kapia pepper (E1), 2% dried sea buckthorn pomace (E2) and 2% dried carrot (E3). Every 2 weeks, 18 eggs/group/period were collected randomly from each group and used to determine the egg quality and nutritional parameters. The results showed that dietary linseed meal and carotenoids sources improved egg color, carotenoids’ accumulation in egg yolk and fatty acid profile, especially the n-3 PUFA content. Dietary carotenoids supplementation reduced, n-6/n-3 ratio, cholesterol content of the egg yolk and improved yolk pH, egg thickness and yolk oxidative stability. In conclusion, the use of these sources of carotenoids in the linseed meal enriched diets could be an effective way to improve the nutritional properties of the eggs without affecting their quality and consumer’s safety.

Effect of Sodium Selenite, Selenium Yeast, and Bacterial Enriched Protein on Chicken Egg Yolk Color, Antioxidant Profiles, and Oxidative Stability

The chicken egg is one of nature's flawlessly preserved biological products, recognized as an excellent source of nutrients for humans. Selenium (Se) is an essential micro-element that plays a key role in biological processes. Organic selenium can be produced biologically by the microbial reduction of inorganic Se (sodium selenite). Therefore, the possibility of integrating Se enriched bacteria as a supplement in poultry feed can provide an interesting source of organic Se, thereby offering health-related advantages to humans. In this study, bacterial selenoproteins from Stenotrophomonas maltophilia was used as a dietary supplement with other Se sources in Lohman brown Classic laying hens to study the egg yolk color, egg yolk and breast antioxidant profile, oxidative stability, and storage effect for fresh and stored egg yolk at 4 ± 2 °C for 14-days. The results showed that dietary Se supplementation significantly (p < 0.05) improved egg yolk color, the antioxidant profile of egg yolk, and breast meat (total carotenoid and phenol content). When the Se treated groups were compared to control groups, there was a significant (p < 0.05) decrease in total cholesterol in fresh and stored egg yolk and breast muscle. In hens that were fed ADS18-Se, the primary oxidation products (MDA) concentrations in the eggs, breast, and thigh muscle, and plasma were significantly (p < 0.05) lower. However, the MDA content increased (p < 0.05) with an extended storage time in egg yolk. In comparison to inorganic Se and basal diets, egg yolk from hens fed organic Se remained fresh for two weeks. The egg yolk color, antioxidant profile, and oxidative status of egg yolk and tissue improve with dietary Se organic supplementation (ADS18 > Se-Yeast). The source of supplemented organic Se is critical for egg enrichment and antioxidant properties. As a result, ''functional eggs'' enriched with organic Se becomes possible to produce.

Effect of dietary phytochemicals from tomato peels and rosehip meal on the lipid peroxidation of eggs from laying hens

The aim of the present study was to evaluate the effects of dietary supplementation with tomato peels (TP) and rosehip meal (RM) on their phytochemicals transfer to the egg, the antioxidant profile and the markers of lipid peroxidation in stored eggs. The experiment was conducted on 42-week-old TETRA SL laying hens, which were assigned to three dietary treatments with 30 birds each: the Control group (CON) received a corn-soybean diet containing 6% flaxseed meal without any by-product addition. Groups TP and RM received Diet CON with additionally 2% TP and 2% RM, respectively. Average daily feed intake, feed conversion ratio and laying percentage were not significantly changed by the dietary treatments. Compared to the other groups, the inclusion of dietary TP led to a significant increase in egg weight (p < 0.05) and vitamin E content in eggs (p < 0.05). The dietary inclusion of RM generated a higher vitamin A content in eggs compared to Groups CON and TP (p < 0.10). After 40 d of storage, in Groups CON, TP and RM the vitamin E contents of eggs deceased by 10.1%, 14.2% and 13.3%, respectively, whereas the reduction of the lutein and zeaxanthin concentration in eggs was more pronounced (by 24.8%, 21.8% and 25.5%, respectively). For the most primary as well as for secondary oxidation products, storage time had a significant influence (p < 0.05) on the degradation process of the eggs. After 40 d of storage, the most distinct reduction in the formation rate of secondary oxidation products was observed in Group RM (by more than 30%), while the reduction for Group TP amounted from 15% to 25%, when compared with Group CON. Therefore, the results of the present study showed a significantly positive effect of RM in retarding the lipid peroxidation process during storage.

Effects of Supplementing Grape Pomace to Broilers Fed Polyunsaturated Fatty Acids Enriched Diets on Meat Quality

Simple Summary

Chicken meat and its products are among the first-choice foods in most countries, due to the health benefits they provide and the relatively low price. However, polyunsaturated fatty acids (PUFA) are highly susceptible to peroxidation, affecting nutritional, sensory characteristics and meat shelf life. A reasonable way and a good tactic to delay their lipid peroxidation would be using a natural antioxidant in feed formulation. Grape pomace (GP) is an agro-industrial by-product with high nutritional value as it is a rich source of polyphenols. The supplementation of broiler diets with grape pomace indicated an intensified color, improved texture and a decrease of lipid peroxidation parameters of broilers’ meat that had been fed with PUFA enriched diets.

Abstract

The effects of using grape pomace as natural antioxidant in polyunsaturated fatty acids enriched broiler diets (4% flaxseed meal) on color, texture and lipid peroxidation of meat were evaluated. The 4-week feeding trial was conducted on 200, Cobb 500 broilers, assigned to 5 groups and housed in an experimental hall with floored pens. Compared to the control group, the diet for the experimental groups included 3% or 6% of two grape pomace varieties, white and red. Diet formulation enrichment with red grape pomace influenced the meat color parameters, underlining an accentuated total color difference (ΔE) for both breast and thigh as compared to the control. The dietary supplementation with grape pomace led to the increase of meat hardness regardless of the amount and variety added. The grape pomace inclusion in broiler diets positively influenced meat color and texture. Regarding the lipid oxidation parameters, there was a decrease of the value of thiobarbituric acid-reactive substances (TBARS) in thigh meat in all experimental groups. Additionally, significant differences were highlighted for breast in 3% white grape pomace and 6% red grape pomace supplemented groups when compared to the control group. In conclusion, the supplementation of broiler diets enriched in PUFA with grape pomace improved meat color and texture, which are essential parameters for consumer’s choice. Also, the grape pomace supplementation indicated an improvement of thigh meat oxidative stability, especially regarding the TBARS value.

Effects of Dietary Inclusion of Bilberry and Walnut Leaves Powder on the Digestive Performances and Health of Tetra SL Laying Hens

Simple Summary

In poultry, diet composition influences growth performance, egg production, as well as digestion. In this study, the effects of dietary additives obtained from bilberry and walnut leaves powder on the digestive performances of Tetra SL hens were evaluated by histologic and morphometric analyses of the intestinal mucosa as well as by the enzymatic activity measurements of alpha-amylase, invertase, maltase, and trypsin correlated with cecum microbiota.

Abstract

The purpose of this study was to examine the effects of dietary inclusion of two additives at the final concentration of 0.5% bilberry (E1) and 1% walnut (E2) leaves powder in the basal diet on digestive health of hens. A total number of 90 Tetra SL hens were divided into two experimental groups (E1 and E2) and one control group (C) consisting of 30 hens each. After four weeks, 10 hens of each group were sacrificed and tissue samples and intestinal content were taken from the duodenum, jejunum, and cecum in order to perform histological, enzymatic, and microbiota analyses. In groups E1 and E2, the histological analysis showed a significant increase of villus height, resulting probably in increased absorption of nutrients in duodenum and jejunum. A decrease in the specific activity of alpha-amylase and trypsin in E1 and E2 for both duodenum and jejunum compared to the control one was also recorded. In addition, the maltase and invertase specific activity in duodenum increased, a tendency that was kept for maltase but not for invertase in jejunum. The cecal microbiota of E1 and E2 individuals was characterized by an increase of Firmicutes and Lactobacilli and a decrease of Enterobacteriaceae. In conclusion, our results indicate that bilberry and walnut leaves additives in feed may improve the health status of the poultry gastrointestinal tract.