Effects of Dietary Coenzyme Q10 on Egg Quality, Yolk Coenzyme Q10 Content, and Antioxidant Capacity in Laying Hens

Consumers demand fresh and high-quality eggs. Egg quality may be represented by shell color, shell weight, egg weight, shell thickness, shell density, albumen height, yolk color, albumen pH and viscosity. Various factors such as strain, age of hen, storage temperature, humidity, the presence of <TEX>$CO_2$</TEX> and storage time affect egg quality. Therefore, we investigated the effects of storage time and temperature on egg quality to define the freshness of Korean market eggs. A total of 1,800 eggs were used for this experiment and were separated into 45 treatments with 40 eggs in each. The treatments were consisted of 15 storage periods (2 d to 30 d) and 3 storage temperatures (<TEX>$2^{\circ}C$</TEX>, <TEX>$12^{\circ}C$</TEX>, <TEX>$25^{\circ}C$</TEX>). Each egg was weighed and broken, and the height of the thick albumen, Haugh units (HU), egg shell color and yolk color were measured by a QCM+system. We also observed the physiochemical properties of eggs such as yolk pH, albumen pH and albumen viscosity. The egg weight, shell weight, albumen height, HU and albumen viscosity significantly decreased with increasing storage time and temperature. However, the albumen and yolk pH significantly increased with increasing storage period and temperature. The interaction effects between the storage period and temperature were significant for shell weight, shell density, egg weight, albumen height, HU, yolk color, yolk pH, albumen pH and albumen viscosity. In the analysis of the correlation with egg quality, the storage temperature exhibited a higher correlation coefficient than the storage period. In conclusion, storage time and temperature are the major factors affecting egg quality, but the storage temperature is a more sensitive determinant of egg quality deterioration compared with the storage period.

A study was carried out to determine the influence of the feather genotype, storage duration, temperature and method on the internal and external qualities of chicken table eggs. A total of 864 table eggs collected from naked neck (Nanaff), frizzle (nanaFf) and normal feathered (nanaff) birds were used in the study. A Completely Randomized Design of four factors namely, feather genotypes, storage temperatures (5ºC and 26ºC), storage duration (0, 7, 14, 21 and 28 days) and storage methods (with or without vegetable oil application) was used. The GLM procedure of GenStat (17th Edition) was used to determine the effects of the four factors and their interactions on external qualities (egg weight, length, and width, shell weight and thickness) and internal qualities (albumen height and weight, yolk height, weight, diameter and colour and Haugh unit) of table eggs. The effect of chicken genotype on proximate composition and nutritional values of table eggs were also determined. Feather genotype had significant (P&lt;0.05) effect on yolk colour and weight whilst storage duration, temperature and method had significant (P&lt;0.05) effects on all the internal qualities of eggs studied except effect of storage duration on yolk colour. The 2-way and 3-way interactions of the factors studied were important sources of variation for many of the internal qualities of eggs studied. With the exception of storage temperature, the other factors studied had significant (P&lt;0.05) effects on many of the external qualities of eggs. The interactions of the factors were not significant (P&gt;0.05) sources of variation for most of the external qualities of eggs. Mutant feather genes (Na and F) positively influence egg qualities which could be utilised to segment the commercial chicken egg market. Keywords: Feather, Frizzle, Naked neck, Yolk colour, Nutritional value.

This study was conducted to evaluate the effects of dietary supplementation with chito-oligosccharide (COS) on egg production, nutrient digestibility, egg quality and blood profiles in laying hens. A total of 240 Hy-line Brown laying hens were randomly allocated into one of the following 5 dietary treatments: i) CON, basal diet; ii) ANT, basal diet+44 mg/kg avilamycin; iii) COS0.2, basal diet+200 mg/kg COS; iv) COS0.4, basal diet+400 mg/kg COS; v) ANTCOS, basal diet+200 mg/kg COS+22 mg/kg avilamycin. The experiment lasted for 6 wk. No change in egg weight (p>0.05) was observed during the trial period. Egg production in ANTCOS treatment was improved (p<0.05) when compared to CON during weeks 4-6. The birds in the COS0.2, COS0.4 and ANTCOS groups had higher (p<0.05) Haugh unit than those fed CON and ANT diets at the end of the 6 th wk. The apparent digestibility of nitrogen in CON group was lower (p<0.05) than in other treatments. The white blood cell (WBC) concentration of birds in the COS0.4 and ANTCOS group was higher (p<0.05) than that of birds in other groups at the end of the 6 th wk. In addition, the differences of WBC counts between the beginning and end of the experiment in COS0.4 and ANTCOS groups were higher (p<0.05) than in CON and ANT groups. At the end of the experiment, the birds fed ANTCOS diet showed higher (p<0.05) total blood protein concentration than those fed CON or ANT diets. In conclusion, dietary supplementation of COS appeared to increase egg production and quality by increasing nutrient digestibility. Additionally, COS improved WBC and total protein concentration.

A total of two hundred 35-week-old (Hy-line brown) layers were randomly assigned to 4 treatments with 10 replications and 5 layers per replicate (1 layer per cage). Dietary treatments were: (1) CON (basal diet); (2) S150, CON + synthetic vitamin E (VE) 150 IU/kg; (3) N50, CON + natural VE 50 IU/kg; and (4) N75, CON + natural VE 75 IU/kg. Dietary VE led to a greater Haugh unit (HU) and VE concentration in yolk (p<0.05) compared with CON group, whereas the egg production, feed intake, egg weight, eggshell strength, yolk height, yolk colour and eggshell thickness were not influenced (p>0.05) throughout the experiment. Blood characteristics were not affected by the administration of VE. Moreover, no difference (p>0.05) was observed on the laying hens’ performance and egg quality between the synthetic and natural VE supplementation. In conclusion, dietary VE improved the VE concentration in yolk and the HU compared with the CON group. VE concentration of yolk and most characteristics were consistent in those birds fed Nat E Ac (50 or 75 IU/kg) compared with those fed Syn E Ac treatment (150 IU/kg), indicating the relative bioavailability of natural VE was two or three times greater than synthetic VE in laying hens.

This study was conducted to investigate the effects of dietary inclusion of alfalfa meal (AM) on the productive performance of Zhuanghe Dagu chickens. A total of 288 35-week-age layers were randomly assigned into four dietary treatments in a 35-day trial. Dietary conditions were based on a basal diet and supplemented with 0, 3, 6, 9% AM (CON, AM3, AM6 and AM9). Results showed that dietary inclusion of AM had positive effects on the egg production rate, feed conversion ratio (FCR), egg mass, yolk colour, albumen height and haugh unit. In addition, the small intestinal morphology such as villus height, crypt width and muscular thickness were improved by including AM in the diet. AM supplementation enriched the microbiota diversity in the caecum. The Firmicutes/Bacteroidetes ratio has decreased, and the Synergistetes has increased in AM supplemented groups compared with the CON group. Predictive functional analysis revealed that metabolic pathways of carbohydrate, lipid, terpenoids and polyketides, etc. were significantly enriched in the experimental groups. A total of 397 differential metabolites have been identified between AM6 group and CON group. Among them, a total of 176 metabolites were upregulated and 221 metabolites were downregulated. Therefore, dietary inclusion of AM was beneficial to improve the laying performance, egg quality, small intestinal morphology, caecal microbiota diversity and caecal metabolic function in Zhuanghe Dagu chickens, with the optimum dose being 6%. Highlights Feeding Dagu chickens with AM containing diet had beneficial effects on the productive performance Dietary inclusion of AM improved intestinal morphology parameters in Dagu chickens The nutritional metabolic function of Dagu chickens was positively affected by including AM

Multiple stressors are believed to deteriorate production performance and cause substantial economic losses in commercial poultry farming. Folic acid (FA) is an antioxidant compound that can improve oocyte function and regulate gut microbiota composition. The current study was conducted to investigate the role of FA in alleviating stress and improving production performance. Sixty Hyline Brown laying hens at 21 weeks of age were randomly divided into three groups, with 10 replicates in each group and each replicate containing two chickens. Each group received basic diet and saline injection (Con group), basic diet with dexamethasone (DXM) injection (DXM group), or basic diet supplemented with FA (13mg/kg in the premix) with DXM injection (FA group). The feeding trial lasted five weeks. Birds in the DXM and FA groups receiving subcutaneous DXM injections at a dosage of 4.50mg/kg per day during the first seven days of the trial. Results showed that the levels of corticosterone, triglyceride, total cholesterol, and malondialdehyde in serum were significantly increased in the DXM group (P<0.05), while the concentrations of FA and 5-methyltetrahydrofolate were decreased in the DXM group (P<0.05). Laying hens in the DXM group had lower laying rates and egg quality, including egg weight, eggshell thickness, eggshell strength, albumen height, and Haugh units (P<0.05). Conversely, FA alleviated these negative impacts. Through transcriptome analysis, a total of 247 and 151 differentially expressed genes were identified among the three groups, and 32 overlapped genes were further identified. Moreover, 44 and 59 differential metabolites were influenced by DXM and FA, respectively. Kyoto Encyclopedia of Genes and Genomes enrichment from the transcriptome and metabolomics showed that the reduced production performance may be due to the disturbance of oocyte production, calcium metabolism, and oxidative stress. Analysis of 16S rRNA gene amplicon sequences revealed the differential microbial composition and potential functional changes among the different groups. LEfSe analysis showed that Mucispirillum and Nautella were the predominant bacteria in the DXM group, while Clostridium was the predominant bacteria in the FA group. Functional prediction demonstrated that stressors enhanced fatty acid biosynthesis, while betaine biosynthesis and retinol metabolism were elevated in the FA group. Dietary FA reversed the elevated levels of bile acids (BA), including cholic acid, taurodeoxycholic acid, and taurochenodeoxycholic acid (P<0.05). The DXM group showed an overall decrease in short-chain fatty acids (SCFA), but FA restored the concentrations of acetic acid, propionic acid, and isobutyric acid (P<0.05). In conclusion, this study reveals that dietary FA can alleviate the degradation of production performance caused by stress through improving circulating antioxidant capacity, maintaining intestinal microbiota homeostasis, and regulating SCFA and BA biosynthesis. Thus, highlighting the prominent role of gut microbe-host interactions in alleviating multi-stresses.

The study aimed to determine the effect of limestone or extruded eggshells on the egg and eggshell quality of laying hens. A total of 240 and 60 eggs were collected from diets D&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt; (limestone) and D&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; (extruded eggshells), respectively, with two levels of calcium source (L): L&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt; (4% limestone or eggshells) and L&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; (8% limestone or eggshells) at 44, 52, 60, 68, and 72 weeks of age. These eggs were obtained from an ongoing project to measure egg quality and dry matter content. Diet D&amp;lt;sub&amp;gt;1 &amp;lt;/sub&amp;gt;showed higher albumen width and height, Haugh unit, and a lower egg yolk height than D&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; (p&amp;lt;0.05). However, the percentage of albumen and yolk weight, as well as the yolk index, tended to be higher in D&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; than in D&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt;. Other egg quality traits were similar between diets (p&amp;gt;0.05). The L&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; was superior to L&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt; in both diets for egg quality traits (p&amp;lt;0.01), and the L&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; in the extruded eggshell diet performed better than L&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; in limestone diet. The egg, albumen, yolk, and eggshell weight, albumen width, and yolk height were increased but the eggshell strength, yolk color, albumen height, eggshell thickness, and membrane thickness were decreased with advancing the birds&amp;apos; age. Egg, albumen, yolk, and eggshell weight, as well as albumen width and yolk height, increased with the advancing age of the birds, whereas eggshell strength, yolk color, albumen height, eggshell thickness, and membrane thickness decreased. Egg, albumen, and eggshell with membrane weight were influenced by the diet × L interaction, while diet × age interaction affected other traits. Egg quality traits were influenced by L x A interaction, but were not affected by D x L x A interaction. The dry matter content of an egg was similar between diets, but moisture content was higher in D&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; than in D&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt;. The dry matter content of albumen was influenced by diet x age interaction. Therefore, the 8% extruded eggshell appears to be the most suitable diet for improving egg and eggshell quality.

Utilization of agricultural by-products in animal nutrition is a practice as old as the domestication of animals. The dried orange peel (DOP), by-product of citrus industry is a promising source of diversified bioactive ingredients with beneficial effects on health. Therefore, this study was carried out to assess the dietary effect of DOP on production and, internal and external egg quality characteristics of laying hens. A total of 60 layers of 25 weeks of age were segregated into three dietary treatment groups using a completely randomized design and reared up to 42 weeks. The dietary treatments were control (basal diet), 5% DOP (basal diet + 5% DOP), and 10% DOP (basal diet + 10% DOP). The study revealed that dietary DOP significantly decreased the feed consumption and feed conversion ratio of layers (p &lt; 0.05) without having any significant effects on egg production, egg weight and egg mass. None of the exterior egg quality parameters were significantly affected by the dietary supplementation of DOP (p &gt; 0.05). Among interior egg quality attributes, the albumen height, albumen index, yolk color, and Haugh unit were all considerably elevated through supplementation of 10% DOP (p &lt; 0.05). Nevertheless, the yolk index was raised by both 5% and 10% DOP supplementation (p &lt; 0.05). The relative weight of ovarian grape and oviduct did not affect by the supplementation of DOP with layer diet (p &gt; 0.05). In summary, it may be said that layer diets can be supplemented with DOP up to 10% level to improve FCR, albumen index, yolk index, yolk color and Haugh unit without compromising egg production or exterior egg quality. Further studies are recommended with layer diets supplemented with DOP at levels higher than 10% to determine the ideal DOP dose during other production periods in various layer strains.&#x0D; Bangladesh Journal of Animal Science 51 (3): 98-106, 2022

This experiment was performed to investigate the effect of flaxseed oil and sunflower oil supplementation on the production performance, egg quality, and egg sensory characteristics in laying hens under density stress. A totaly of 144 Atak-S hens were used. The animals were assigned into 2 groups as stressed and unstressed. These were allocated into three subgroups as those who were fed with basal diet, diets containing 2% sunflower oil, and 2% flaxseed oil. Density stress was applied to those in the stress group by providing an area of 357 cm2 per hen. Egg production performance, average egg weight and egg mass, eggshell weight, eggshell thickness, eggshell strength, Haugh unit, albumen height, yolk color and sensory carateristics of the eggs were measured. Flaxseed oil reduced egg production and egg mass in those who are unstressed. On the contrary, it increased egg production and egg mass in the stressed groups. Sunflower oil was found to increase the average egg weight and egg mass in all groups. It was observed that when sunflower oil was added to the diets of the stressed chickens, the yolk color index decreased. In addition, it was determined that the eggs of the nostressed hens taste better than the stressed chickens. It was determined that flaxseed oil added to the diets increased the sensory quality of the eggs in both stressed and non-stressed groups. Therefore, incorporation of flaxseed and sunflower oil into the diets of layer hens can be recommended.

700 Rhode Island Red (RIR) and 600 Bovans white exotic poultry breeds were maintained under intensive management by private poultry farm in Mekelle were studied for external and internal egg qualities.Weight of egg (g), length (cm) and width of egg (cm), shape index, egg shell thickness (mm) and egg shell weight (g) were studied as external egg quality traits while yolk and albumen weight (g), yolk and albumin height (mm), Haugh Unit (HU) and yolk color were recorded as internal egg quality traits of RIR and Bovans White.Among external egg quality Weight, length and width of egg of RIR was significantly higher (p<0.05)than Bovans White while shape index, egg shell thickness and egg shell weight (g) were found to be non significant.Among internal egg quality yolk and albumen weight, yolk and albumin height of RIR was significantly higher (p<0.05)than Bovans White while Haugh Unit (HU) and yolk color were found to be non significant.

There are many kinds of anti-oxidant materials in natural plant resources. The Siberian ginseng and Eucommia are well known as anti-oxidant and medicinal plants. To investigate the effect of their anti-oxidant-like activity on telomere quantity and egg quality, diets containing Siberian ginseng leaf and Eucommia leaf at 0.5% and 1% were given Hyline Brown commercial laying hens during two periods of age: 20 to 30 wks and 60 to 70 wks. The amount of telomere in lymphocyte, liver, ovary, heart and lung was analyzed by quantitative fluorescence in situ hybridization using telomeric DNA probe. Egg weight, albumin height, Haugh unit, egg yolk color, egg shell color, egg shell thickness, egg shell weight and egg shell density were measured to analyze egg quality. The chickens consuming diets Siberian ginseng and Eucommia had higher telomeric DNA in lymphocytes than control chickens in younger layers whereas no significant differences were detected in all target cells analyzed from older layers. Egg quality was increased in younger hens with dietary supplementation as determined by egg weight, albumin height and Haugh unit but there were no effects in older hens. These results imply that dietary supplementation of Siberian ginseng and Eucommia in layers improves bio-activity and egg quality at early laying stage.

Effects of green tea powder on production performance, egg quality, and blood biochemical parameters in laying hens

Chinese herbs have been used as feed additives in animal production. This study investigated the effects of a Chinese herbal feed-additive (TCM, which contained Elsholtzia ciliate, Atractylodes macrocephala, Punica granatum pericarpium, and Cyperus rotundus) on the production performance, egg quality, antioxidant capacity, immunity, and intestinal health of Roman laying hens. A total of 720 28-week-old hens were randomly allotted to three groups with six replicates of forty hens each. The groups were fed a basal diet (CON group), a basal diet with 50 mg/kg zinc bacitracin (ABX group), or a basal diet with 400 mg/kg TCM (TCM group) for 56 days. The results showed that the TCM group increased egg production, egg mass, albumen height, and Haugh unit compared with the CON group (p < 0.05). There were no significant differences in egg weight, feed intake, feed conversion rate, and eggshell strength among all three groups (p > 0.05). Compared with the CON group, the TCM group enhanced the activities of glutathione peroxidase, total antioxidant capacity, and superoxide dismutase in serum and liver, and reduced malondialdehyde content (p < 0.05). The TCM also increased the levels of interleukin-2, interferon-γ, immunoglobulin A, immunoglobulin M, and immunoglobulin G, and decreased the levels of interleukin-6 and interleukin-8 compared with the CON group (p < 0.05). Furthermore, the TCM group increased jejunal goblet cell density and decreased ileal crypt depth and lymphocyte density compared with the CON group (p < 0.05). The results of 16S rRNA demonstrated that the TCM can change the diversity and composition of intestinal microbiota. At the phylum level, the abundance of Bacteroides increased while that of Firmicutes decreased in the TCM group (p > 0.05). At the genus level, the abundance of Lactobacillus, Rikenellaceae_RC9_gut_group, and Phascolarctobacterium increased while that of Bacteroides and unclassified_o__Bacteroidales decreased in the TCM group (p > 0.05). The effects of ABX were weaker than those of the TCM. In conclusion, the TCM has positive effects on production performance and the intestinal health of hens.

This study was conducted to reveal the differences among the internal quality characteristics of brown and white shell table eggs and to examine the relationship between quality characteristics. A total of 235 eggs from brown and white laying hens (Nick-chick; 95 wk of age) were used in this study. Internal egg quality characteristics including egg weight, albumen height, Haugh Unit, yolk height, yolk index, albumen pH, yolk pH, yolk color were determined. The Haugh unit (P<0.001), Albumen height (P<0.001), yolk L* (P<0.001) and yolk b* (P<0.05) values of white shell eggs were higher than that of brown shell eggs. On the contrary, the yolk a*(P<0.01), yolk height (P<0.01) and yolk index (P<0.01) values of white shell eggs were lower than that of brown shell eggs. There were no significant differences were found between white and brown shell eggs for egg weight, albumen and yolk pH values. Significant (P<0.001) positive correlations were found between albumen height and Haugh unit (r= 0.97), yolk height and yolk index (r=0.91), albumen pH and yolk pH (r=0.95) in internal egg quality of white shell eggs. Similarly, there were significant (P<0.001) positive correlations between albumen height and Haugh unit (r= 0.97), yolk height and yolk index (r=0.88), egg weight and albumen height (r=0.39), albumen height and yolk height (r=0.35), Haugh unit and yolk index (r=0.36) in internal egg quality of brown shell eggs. Significant (P<0.001) negative correlation were found between yolk L* and yolk a* (r=-0.41) in white shell eggs, and yolk L* and yolk a* (r=-0.56) in brown shell eggs. No significant relationships were observed among others internal egg quality criteria.

In this study, sixteen egg quality traits, including egg weight, albumen weight, yolk weight, eggshell weight, albumen weight ratio, yolk weight ratio, eggshell weight ratio, yolk color, eggshell color, egg height, egg width, shape index, albumen height, Haugh unit, eggshell thickness, and eggshell strength were investigated in 12 strains of Korean native chicken using 600 eggs from birds at 38 weeks of age. Results showed that the Korean White Leghorn F strain had the highest egg weight of 62.7 g and the lowest (47.5 g) was observed in the Korean native chicken W strain. The Haugh unit was significantly different between strains. The mean Haugh unit for Korean native chicken ranged between 84.2 (L strain) and 76.0 (F strain), with an overall average of 79.9. Eggshells were the thinnest in Korean Rhode Island Red C and D strains (0.342 mm), whereas the highest eggshell thickness (0.393 mm) was observed in the Korean White Leghorn K strain. Korean Rhode Island Red C and D strains had low egg strength compared to that of other strains. Korean Cornish and Korean native chicken showed significant differences in egg quality traits between strains within breeds. Positive correlation coefficients were observed between egg weight and egg quality traits. The traits for color showed zero or low correlations with most egg quality traits. Egg shape index showed no correlation with most egg quality traits. Albumen height and the Haugh unit showed a positive correlation with albumen traits. Eggshell strength showed a positive correlation with eggshell traits.