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Simple Summary: Our study investigates the genetic basis of translucent eggshell formation by analyzing gene expression in the oviduct's isthmus region of hens laying translucent eggs. Our findings highlight that alterations in collagen-related pathways are central to changes in the eggshell's physical structure, leading to translucence. This research offers insights for strategies to reduce translucent egg formation. The presence of translucent eggshells is a type of egg quality issue that impacts egg sales. While many researchers have studied them, the exact mechanisms behind their formation remain unclear. In this study, we conducted a transcriptomic differential expression analysis of the isthmus region of the oviduct in both normal egg- and translucent egg-laying hens. The analysis revealed that differentially expressed gene pathways were predominantly concentrated in the synthesis, modification, and transport of eggshell membrane proteins, particularly collagen proteins, which provide structural support. These findings suggest that variations in the physical structure of the eggshell membrane, resulting from changes in its chemical composition, are the fundamental cause of translucent eggshell formation. This research provides a theoretical reference for reducing the occurrence of translucent eggs. [ABSTRACT FROM AUTHOR]

This experiment was designed to study the effects of a bacteria enzyme complex product on egg production performance, egg quality, serum biochemical index, and ammonia emissions in manure of laying hens. One thousand and eight hundred 400-day-old commercial generation Hyline brown laying hens were selected for the experiment and randomly divided into 3 groups with 600 hens in each group. There were 3 replicates within each group with 200 hens in each replicate. The control group was fed with basic diets. Group Ⅰ and group Ⅱ were fed with basic diets supplemented with 0.5 g/kg and 1.0 g/kg of bacterial enzyme complex products, respectively. The experimental period was conducted for 42 days. Results showed that, compared with the control group, the egg production rate of the experimental groups was significantly increased (P<0.05), while the feed to egg ratio and egg breaking rate were significantly reduced (P<0.05). The eggshell thickness, eggshell strength, and Hastelloy unit of the two experimental groups were also significantly increased (P<0.05), with the group Ⅱ significantly higher than the group Ⅰ (P<0.05). The serum uric acid (UA) content in the experimental groups of laying hens was significantly reduced (P<0.05). Compared with the control group, the ammonia concentration in the manure of the experimental group was significantly reduced (P<0.05), with the group Ⅱ significantly lower than the group Ⅰ (P<0.05). These results indicat that the bacterial enzyme complex product increases egg production performance and egg quality, decreases the ammonia concentration in the manure of laying hens. [ABSTRACT FROM AUTHOR]

Simple Summary: The vocalisations that an animal produces could provide a window into its emotional state. More knowledge on how emotional states are expressed in the vocalisations of birds could even be used to improve the welfare of farmed poultry. The present study introduced a novel device designed to trigger different emotional states in hens using different physical and chemical stimuli. The final device was able to elicit a broad range of vocalisations without any human interference. It was found that the hens not only actively used the device as a feeder but also responded vocally to both positive and negative stimuli. Preliminary findings indicate that the vocal responses of the hens vary as a function of the intensity of the emotional state they experience. This research contributes to understanding poultry emotions and has the potential to open new opportunities in understanding and improving their welfare in farming environments. Understanding the emotional states of animals is a long-standing research endeavour that has clear applications in animal welfare. Vocalisations are emerging as a promising way to assess both positive and negative emotional states. However, the vocal expression of emotions in birds is a relatively unexplored research area. The goal of this study was to develop an interactive feeding system that would elicit positive and negative emotional states, and collect recordings of the vocal expression of these emotions without human interference. In this paper, the mechatronic design and development of the feeder is described. Design choices were motivated by the desire for the hens to voluntarily interact with the feeder and experience the different stimuli that were designed to induce (1) positive low-arousal, (2) positive high-arousal, (3) negative low-arousal, and (4) negative high-arousal states. The results showed that hens were motivated to engage with the feeder despite the risk of receiving negative stimuli and that this motivation was sustained for at least 1 week. The potential of using the interactive feeder to analyse chicken vocalisations related to emotional valence and arousal is being explored, offering a novel proof of concept in animal welfare research. Preliminary findings suggest that hens vocalised in response to all four stimulus types, with the number of vocalisations, but not the probability of vocalising, distinguishing between low- and high-arousal states. Thus, the proposed animal–computer interaction design has potential to be used as an enrichment device and for future experiments on vocal emotions in birds. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the efficacy of Bacillus-based probiotics supplemented at two different levels to modulate the productive performance, egg quality, tibia traits, and specific cecal bacteria counts of Hy-Line Brown layers from 25 to 37 weeks of age. Methods: A total of 216 twenty-five-week-old hens were randomly distributed into 3 experimental diets with 12 replicates of 6 birds per cage. Diets included basal diet supplemented with 0 (CON), 3x108 (PRO1), or 3x109 (PRO2) colony-forming unit (CFU) of the test probiotic containing Bacillus subtilis PB6, Bacillus subtilis FXA, and Bacillus licheniformis G3 per kilogram of feed. Results: Improved egg weights and mass at 29 weeks; and feed intake at 31 weeks (p<0.10) were noticed with the probiotic-supplemented PRO1 and PRO2 diets. Considering egg quality, the shell thickness, Haugh units, and yolk color were improved; but yolk cholesterol was lowered (p<0.05) with PRO1 and PRO2 diets at 29 weeks. At both 33 and 37 weeks, the egg-breaking strength, shell color and thickness, albumen height, Haugh units, and yolk color were improved; but yolk cholesterol was similarly lowered (p<0.05) with the PRO1 and PRO2 diets. Improved tibia Ca, ash, weights, and density; and raised cecal counts of Bifidobacteria and Lactobacilli (p<0.05) were noticed with PRO1 and PRO2 diets. Improved tibia P but reduced Clostridia counts (p<0.10) were also observed with the PRO1 and PRO2 diets. Conclusion: Probiotic supplementation of Bacillus subtilis PB6, Bacillus subtilis FXA, and Bacillus licheniformis G3 at 3x108 CFU/kg of feed is adequate to significantly improve egg quality, lower yolk cholesterol, enhance several tibia traits, and raise the populations of beneficial cecal bacteria. Modest improvements in several productive parameters and tibia P but reduced Clostridia were also observed; and could warrant further investigation of probiotic effects beyond the current test period. [ABSTRACT FROM AUTHOR]

The experiment aimed to explore the effects of compound organic acidifiers on the production performance, egg quality, serum biochemical indexes, and economic benefits of laying hens in the late laying period. Five hundred and forty 72-week-old Jingfen No.2 laying hens with similar body condition were selected and randomly divided into three groups (CON group, L-COA group, and H-COA group), with six replicates in each group and 30 hens in each replicate. Each group was fed the same diet. The CON group drank tap water throughout the whole process. The L-COA group and H-COA group added 0.10% and 0.15% compound organic acidifiers to the drinking water, respectively. The test period was 42 days. The results showed that compared to the CON group, the egg production rate and egg qualified rate of the L-COA group were significantly increased (P<0.05), the egg production rate, average egg weight, and egg qualified rate of the H-COA group were significantly increased (P<0.05). The eggshell strength and egg yolk score of the L-COA group were significantly improved (P<0.05). The serum low-density lipoprotein content and alanine aminotransferase activity in the L-COA group and H-COA group were significantly reduced (P<0.05). The breeding profits of the L-COA group and H-COA group increased by 1.08% and 13.64%, respectively. The study indicates that adding compound organic acidifiers to the drinking water of laying hens during the late laying period has a positive effect on egg production efficiency, egg quality, serum biochemical indexes, and economic benefits, and the better effect is achieved when the added amount of compound organic acidifiers is 0.15%. [ABSTRACT FROM AUTHOR]

The experiment was to investigate the effects of bacterial-enzyme complex on the production performance, egg quality, egg composition, and nutrient apparent metabolic rate in wheat-based laying hens. A total of 360 Jinghong laying hens were randomly divided into three groups with 10 replicates in each group and 12 laying hens in each replicate. The control group was fed with corn-soybean meal diet. The wheat group used 10% wheat to replace the same proportion of corn in the control group diet. The bacterial-enzyme complex group was supplemented with 0.02% bacterial-enzyme complex on the basis of wheat group diet. The pre-test period was three days, and the formal test period was 28 days. The results showed that there was no significant difference in production performance, egg quality, and egg composition among the control group, wheat group, and bacterial-enzyme complex group (P>0.05). The lutein content of egg yolk in wheat group decreased gradually with the increase of experiment time. On the 22nd, 25th, and 28th day, the lutein content of egg yolk in wheat group was significantly lower than that in control group (P<0.05), and the lutein content of egg yolk in bacterial-enzyme complex group was significantly higher than that in wheat group (P<0.05). The apparent metabolic rates of dry matter, crude protein, calcium, and phosphorus in wheat group were lower than those in control group (P>0.05), while the apparent metabolic rates of crude protein and phosphorus in bacterial-enzyme complex group laying hens were significantly higher than those in the control group and wheat group (P<0.05). The study indicates that using 10% wheat instead of corn can not affect egg quality and egg composition, but can reduce yolk color and lutein content. Bacterial-enzyme complex can increase yolk lutein content of wheat group, improve yolk color and improve nutrient apparent metabolic rate of laying hens. [ABSTRACT FROM AUTHOR]

This experiment was conducted to study the effects of different levels of quercetin in diets on the laying performance, egg quality, and lipid metabolism of Hyline brown laying hens in late laying period, and to determine the optimal supplemental level of quercetin in laying hens. A total of 1 600 sixty-week-old healthy Hyline brown laying hens were randomly divided into four groups with four replicates per group and 100 laying hens per replicate. Hens in control group were fed a basal diet, and hens in experimental groups were fed diets supplemented with 200, 400, and 800 mg/kg quercetin, respectively. The pre-test lasted for one week and the formal test lasted for 60 days. The results showed as follows: Compared with the control group, the laying rate of Hyline brown laying hens in all quercetin groups was significantly increased (P<0.05), the egg weight and average daily egg weight of the test group 2 and group 3 were significantly increased (P<0.05), and the ratio of feed to egg was significantly decreased (P<0.05). Compared with the control group, the eggshell thickness and egg weight of the test group 2 and group 3 were significantly increased (P<0.05), the eggshell strength and eggshell weight in the test group 2 were significantly increased (P<0.05), and the yolk color and Haugh unit were significantly improved in all quercetin groups (P<0.05). The crude protein content in yolk of the test group 2 and group 3 was significantly increased (P<0.05), the cholesterol and triglyceride content in yolk of the test group 2 were significantly decreased (P<0.05), and the phospholipid content in yolk of all quercetin groups was significantly increased (P<0.05). Compared with the control group, the serum adiponectin content in the test group 2 and group 3 was significantly increased (P<0.05), the serum leptin content in all quercetin groups was increased (P<0.05), and the serum cholesterol, triglyceride, low density lipoprotein cholesterol, and glucose content in the test group 2 were significantly decreased (P<0.05). The serum free fatty acid content in the test group 2 and group 3 was significantly decreased (P<0.05). The results show that adding proper quercetin to the production of Hyline brown laying hens can improve the laying performance and egg quality, regulate the metabolism of blood lipids, and improve the body's health. The appropriate supplemental level of quercetin is 400 mg/kg. [ABSTRACT FROM AUTHOR]

BACKGROUND: ε-polylysine hydrochloride (ε-PLH) is a naturally occurring antimicrobial peptide extensively utilized in the food and medical industries. However, its impact on animal husbandry remains to be further explored. Therefore, the present study aimed to determine the effect of ε-PLH on laying hens' health and laying performance. RESULTS: Dietary supplementationwith ε-PLH to the diet significantly increased average egg weight during weeks 1-8. Meanwhile, compared with the control group, supplementation with ε-PLH decreased the feed egg ratio during weeks 9-12 and egg breakage rate during weeks 9-16, whereas it increased eggshell strength during weeks 1-4 and 13-16 . The ε-PLH 0.05% group increased yolk percentage during weeks 5-8 and yolk color during weeks 1-4 . Furthermore, ε-PLH supplementation significantly increased the concentrations of total protein, albumin, globulin and reproductive hormones estradiol, as well as decreased interleukin-1 beta and malondialdehyde in the serum. Compared with the control group, supplementation with 0.05% ε-PLH significantly increased the relative abundance of Cyanobacteria and Gastranaerophilales and decreased the abundance of Desulfovibrio and Streptococcus in the cecum microbiota. In addition, ε-PLH 0.1% supplementation also increased acetic acid content in the cecum. CONCLUSION: Dietary supplementation with ε-PLH has a positive impact on both productive performance and egg quality in laying hens. Furthermore, ε-PLH can also relieve inflammation by promoting the immunity and reducing oxidative damage during egg production. ε-PLH has been shown to improve intestinal morphology, gut microbial diversity and intestinal health. [ABSTRACT FROM AUTHOR]

This experiment was conducted to investigate the effects of Antrodia cinnamomea culture on performance, egg quality and serum antioxidant indexes of laying hens in late peak period. A total of 288 Hyline white laying hens (400 days of age) with similar body condition and laying performance in the late peak period of laying were randomly divided into four groups: control group and low, medium and high dose groups. Laying hens in control group were fed a basal diet, and laying hens in low, medium and high dose groups were fed the basal diet supplemented with 50 mg/kg, 100 mg/kg and 200 mg/kg Antrodia cinnamomea culture, respectively. The pre-test lasted for seven days and the experiment lasted for 28 days. The results showed as follows: compared with the control group, the laying rate, daily feed intake and daily egg weight in the Antrodia cinnamomea culture group were slightly increased, and the ratio of feed to egg in the 50 mg/kg and 100 mg/kg Antrodia cinnamomea culture groups were slightly lower than that in the control group, but the difference was not significant (P>0.05); Antrodia cinnamomea culture had no significant effect on egg quality. The proportion of dark red liver in 200 mg/kg Antrodia cinnamomea culture group was 83.33% with the increase of Antrodia cinnamomea culture dosage. With the increase of Antrodia cinnamomea culture, the pathological changes of liver tissue slices of laying hens could be reduced or disappeared; the superoxide dismutase (SOD) content of 200 mg/kg Antrodia cinnamomea culture group was significantly higher than that of 50 mg/kg group and control group (P<0.05), but the contents of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) were not significantly different among all groups (P>0.05). When 50 g and 100 g Antrodia cinnamomea culture were added to the diet per ton, 72 laying hens fed for 28 days could gain an additional profit of 34.4 yuan and 58.4 yuan, respectively. In conclusion, Antrodia cinnamomea culture can improve the production performance of laying hens in the late peak period, reduce the incidence of fatty liver of laying hens, improve serum antioxidant indexes, and increase the breeding income of farmers, among which the 100 mg/kg group of Antrodia cinnamomea has the best profit. [ABSTRACT FROM AUTHOR]

The study was conducted to investigate the effects of dietary marigold lutein on egg quality, serum biochemistry, immune function and antioxidant capacity of laying hens. A total of 432 Roman grey laying hens aged 20-21 weeks were randomly divided into 6 groups. The control group was fed the basal diet, and the positive control group was fed the diet supplemented with 800 mg/kg Marigold lutein (Lidar Company, LDE), and the other 4 groups were experimental groups, there diets were supplemented with 200, 400, 800 mg/kg and 1 600 mg/kg marigold lutein, respectively (Chenguang Company, CG). After 7 days of pre-feeding,the whole experiment last 56 days .The eggs quality was determined on day 28 and day 56, blood samples were collected on day 56 to determine immune indexes, antioxidant capacity and serum biochemical indexes. The results showed as follows: ① In terms of egg quality, the yolk color of all test groups and positive control group except CG-200 group was significantly improved on day 28, and the yolk color of all test groups and positive control group was significantly improved on day 56, but marigold lutein had no significant effect on other eggs quality indexes. ② In terms of serum biochemistry, the content of HDL-C in the CG-1600 group was significantly increased, and the activity of AST was also significantly increased, while the activity of ALT was significantly decreased in the CG-200 group, and ALP activity was significantly increased. ③ In terms of immune function, IgG in serum of laying hens in the CG-200 group and positive control group was significantly increased; IgA in serum of laying hens in the CG-400, CG-1600 groups and positive control group was significantly increased. IgM in serum of laying hens in the CG-800 and CG-1600 groups and positive control group was significantly increased. IL-10 in serum of laying hens in the CG-200 group was significantly increased, while IFN -γ in serum of laying hens in the positive control group was significantly increased. ④ In terms of antioxidant capacity, MDA in serum which in the CG-400 group was significantly decreased; CAT activity in the CG-400 and CG-800 groups was significantly increased; the activity of SOD in serum in the CG-800, CG-1600 groups and positive control group was significantly increased. All the dose groups had no significant effect on the enzyme activity of GSH-Px in serum. In conclusion, Adding proper dosage of marigold lutein in diet can significantly improve the yolk color, and enhance the immune function and the antioxidant capacity of laying hens. [ABSTRACT FROM AUTHOR]

The experiment aimed to investigate the effects of Bacillus subtilis and Enterococcus faecium on the production performance, egg quality, serum biochemical indexes, immune indexes, and intestinal microbes of laying hens. A total of four hundred .38-week-old Hyline Brown laying hens were randomly divided into four groups, with five replicates per group and 20 hens per replicate. Group 1 (control group) were fed with a basic diet. Group 2 received a basic diet supplemented with 200 g/t of Bacillus subtilis. Group 3 received a basic diet supplemented with 200 g/t of Enterococcus faecium. Group 4 received a basic diet supplemented with a composite probiotic consisting of 100 g/t of Bacillus subtilis and 100 g/t of Enterococcus faecium. The experimental period lasted for 56 days. The results showed that compared to the control group, the egg production rate of all the experimental groups increased (P<0.05), and the mortality rate and feed to egg ratio decreased (P<0.05). The eggshell thickness and yolk color increased (P<0.05). The total protein and globulin levels in the serum of laying hens in all the experimental groups increased (P<0.05), and the levels of immunoglobulin G, immunoglobulin M, and y -interferon in the serum all increased (P<0.05). The number of lactic acid bacteria in the cecum chyme of the laying hens increased (P<0.05), while the number of Escherichia coli and Salmonella decreased (P<0.05). The study suggests that Bacillus subtilis and Enterococcus faecium can improve the production performance of laying hens, maintain intestinal health, and enhance serum biochemical and immune indexes. [ABSTRACT FROM AUTHOR]

Feeding animals with lactobacilli strains is a biotechnological strategy to improve production, food quality, and animal health. Thus, this study aimed to select new lactic acid bacteria (LAB) able to improve laying hens health and egg production. Forty Bovans White layers (two days old) were randomly divided into four experimental groups that receive an oral gavage with saline solution (control group) or with one of the three lactobacilli selected (KEG3, TBB10, and KMG127) by their antagonistic activity against the foodborne pathogen Bacillus cereus GGD_EGG01. 16 S rRNA sequencing identified KEG3 as Lentilactobacillus sp., and TBB10 and KMG127 as Lactiplantibacillus sp. The data showed that feeding birds with LAB increased weight uniformity and improved the internal quality of the eggs (high yolk index and Haugh unit) compared with the control group (p < 0.05). Beta-diversity analysis showed that LAB supplementation modifies the cecal microbiota of laying hens. The prokaryotic families Bacteroidaceae, Ruminococcaceae, Rikenellaceae, and Lactobacillaceae were most important to the total dissimilarity of the cecal microbial community (calculated by SIMPER test). At end of in vivo experiments, it was possible to conclude that the feed of laying hens with Lentilactobacillus sp. TBB10 and Lentilactobacillus sp. KEG3 can be an important biotechnological tool for improving food quality and animal health. [ABSTRACT FROM AUTHOR]

This review article highlighted the effects of different rearing systems on egg quality parameters and the welfare of laying hens. Different housing systems for laying hens continue to cause controversy among consumers, researchers, environmentalists, and producers. The main concern and issue is the effect of these systems on bird health, behavior, and egg quality. In the European Union, public concern has increased about animal welfare in the poultry sector, since 2012 conventional battery cages (CC) for laying hens have been banned and replaced by other alternative housing systems: enriched cages (EC) and non-cages systems, such as aviaries (AV), and free-range system. The rearing systems and maintenance technologies of the laying hens can also influence the quality parameters of the egg. Conventional rearing systems can involve overcrowding of hens, poor hygiene conditions, or lack of access to space and natural light, which can lead to stress and disease in the birds and, by implication, reduced egg quality. The use of modern technologies in the breeding of laying hens can contribute to the improvement of egg quality parameters and the well-being of laying hens. These technologies include automated systems for feeding and watering, temperature and humidity control in rearing houses, artificial lighting, and the use of food supplements to ensure adequate nutrient intake. [ABSTRACT FROM AUTHOR]

Eggs are a great source of animal protein that are rich in fatty acids, selenium, B vitamins, provitamin A, amino acids, and folic acid. Egg quality and yolk colour are important attributes for consumers. They associate a higher intensity colour of yolk with a healthy egg which its rich in nutrients. Because hens are unable to synthesise pigments, they must come from feed mixtures. Furthermore, the synthetic colourants are added to laying hens diets to improve the yolk colour intensity. However, human health received more attention in the last time, so, the consumers are attracted by natural-coloured eggs. Carotenoids are the most numerous and widespread group of pigments in nature. They are a class of widely distributed pigments that include red, yellow, and orange colour. Numerous studies have examined the use of carotenoids, particularly yellow carotenoids, in animal feed, which aid to make egg yolks more orange in colour. They are found in different plants, microalgae, bacteria, fungi and have various biological functions, including increasing production, antioxidant, anti-inflammatory, antibacterial and immunomodulator role. For practical purposes, the cost of carotenoids from natural sources needs to be considered. The objective of this review was to summarise the recent findings in available literature data on the supplementation with natural pigments based on marigold and calendula flowers and paprika extracts for egg quality and yolk colour pigmentation which are preferred over pigments of synthesis, due to their costs and biodisponibility. [ABSTRACT FROM AUTHOR]

The experiment was conducted to study the effect of compound plant essential oils on the production performance and egg quality of laying hens. A total of 13 664 Dawu Jinfeng laying hens with similar body weight and late laying period (362~368 days of age ) were randomly divided into two groups, a control group and a compound plant essential oil group, with four replicates in each group and 1 708 laying hens in each replicate. The laying hens in the control group were fed a basal diet, and the laying hens in the compound plant essential oils group were fed a basal diet supplemented with compound plant essential oils. The trial period was 14 days. The results showed that compared with the control group, the laying rate of laying hens in the compound plant essential oils group was significantly increased (P<0.05), the average egg weight showed an increasing trend (P>0.05), the sand shell egg rate was significantly decreased (P<0.05), and the feed to egg ratio was decreased (P>0.05). Compared with the control group, the egg yolk ratio of the compound plant essential oils group was significantly decreased (P<0.05), and the eggshell intensity had a rising trend. The egg yolk color, hardness, and wetness in the compound plant essential oils group were significantly increased (P<0.05). The study indicates that adding compound plant essential oils to the diet can increase the production performance and egg quality of laying hens. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the effect of replacing soybean meals with legume grains in diets on laying performance of hens and egg quality, with particular emphasis on egg lysozyme content. The study included 4 breeds/strains of laying hens included in the conservation programme in Poland, i.e.: Green-legged Partridge (Z-11), Yellow-legged Partridge (Ż-33), Rhode Island Red (R-11), and Leghorn (H-22). At 41–56 weeks of age, the hens of each strain were divided into two groups: I (control) − fed ad libitum with a standard diet based soybean meal, and II (experimental) − fed ad libitum with a diet that contained beans, peas and lupins instead of soybean meal. At 56 weeks of age, 32 eggs were taken at random from each group of hens and each strain, which were subjected to quality assessment. The results of the study confirm the possibility of feeding the above-mentioned hens with diets in which soybeans were replaced with 28% of faba bean, pea, and yellow lupin grains without a significant effect on laying performance, but with a change in some egg quality characteristics. In groups of hens fed a diet without soybean, a decrease in egg and albumen weight, albumen and yolk pH values, and an increase in yolk yellowness were recorded, as well as an increase in Haugh units and air cell height and shell porosity. There was a significant effect of genotype and diet and simultaneously of both factors on the content and activity of lysozyme in the thin and thick albumen. In the experimental groups, the average content and activity of lysozyme in the thin albumen decreased and in the thick albumen increased. Regardless of diet, statistically significant variation in egg internal quality and egg shell quality between hen strains was shown, as well as a correlation between the content and activity of lysozyme in eggs and shell colour. [ABSTRACT FROM AUTHOR]

The experiment aimed to the use of some contents of steam-pressed corn to replace corn in the diet of laying hens to study the effects of corn on performance and egg quality of laying hens. A total of 10 000 40-weekold Jingfen No. 6 laying hens with good health, similar body weight and egg production rate were selected and divided into the control group and experimental group by single factor experiment, with five replicates in each group and 1 000 birds in each replicate. The control group was fed a basal diet, and the experimental group was fed 100 kg steam-pressed corn to replace the corn in the basal diet. The experiment lasted for 30 days. The results showed that compared with the control group, the average daily feed intake of the experimental group was increased by 1.99% (P>0.05), the average daily egg production rate and average egg weight were increased by 3.85% and 0.36%, respectively (P<0.05); the feed to egg ratio of the experimental group was 0.05% lower (P>0.05). The eggshell strength and Haugh unit ratio of the experimental group were 0.03 kgf and 0.16% higher than those of the control group (P>0.05); the egg white height of the experimental group was 0.01 mm lower (P>0.05) than the control group. The results showed that the use of 100 kg steam-pressed corn in the diet to replace corn could improve the performance of laying hens, but there was no significant improvement in egg quality. [ABSTRACT FROM AUTHOR]

Simple Summary: Cold stress is considered an environmental stress and is an important managemental factor in regions where winter temperatures drop below 18 °C. Although a low temperature lowered the productive performance of laying hens, there are still unanswered questions as to the physiological changes that occur when they are exposed to low temperature, especially changes in antioxidants and stress indicators, which prompted us to set up the current study. Laying hens reared at low temperature (12 ± 4.5 °C) showed impaired laying performance compared with laying hens reared at normal temperature (24 ± 3 °C). However, eggshell color was intensified in laying hens exposed to low temperature. During the early stage of exposure to low-temperature stress, malondialdehyde levels in the egg yolk increased in laying hens raised at low temperature vs. normal temperature. However, yolk corticosterone, an indicator of stress responses, remained unchanged. Low temperature had an impact on total cholesterol and triglyceride levels in serum increases in laying hens reared at low temperature. In essence, low temperature in laying hens altered antioxidant systems and lipid metabolism without inducing stress responses. The present study investigated the effect of low temperature on laying performance, egg quality, body temperature, yolk malondialdehyde, yolk corticosterone, and serum biochemistry in laying hens. A total of 40 laying hens (Hy-Line Brown) aged 36 weeks were housed in one of two environmental chambers kept at 12 ± 4.5 °C (low temperature) or 24 ± 3 °C (normal temperature) for 4 weeks. Low vs. normal temperature significantly increased (p < 0.05) live body weight, feed intake, and feed conversion ratio in laying hens. Skin surface temperature, but not rectal temperature, was decreased in laying hens exposed to low vs. normal temperature. Hens exposed to low temperature laid an intense eggshell color compared with those raised in a normal temperature. Malondialdehyde concentrations in yolk were increased in low-temperature-exposed laying hens compared with those at normal temperature conditions, but this effect was only noted on day 7, post the low-temperature exposure (p = 0.04). Finally, low vs. normal temperature increased the concentrations of total cholesterol and triglyceride in serum. Collectively, this study indicates that exposure to low temperature in laying hens initially disrupted antioxidant system and altered lipid metabolism in laying hens without inducing stress responses. [ABSTRACT FROM AUTHOR]

The experiment was to study the effect of two different Chinese Herbal-probiotics compounds on the production performance and ovarian function of laying hens. A total of 450 fifty-week-old Hyline brown laying hens with similar 1aying rates and body weights were randomly divided into five groups with six replicates in each group and 15 chickens in each replicate. The laying hens in the control group (CK group) were fed a basal diet, and the F1-1 group and F1-2 group were supplemented with 1‰ and 2‰ Chinese herbal-probiotics compound 1 (F1, composed of Astragalus, Radix Isatidis, Epimedium, etc. and probiotics) in the basal diet. The F2-1 group and F2-2 group were supplemented with 1‰ and 2‰ Chinese herbal-probiotics compound 2 (F2, composed of Angelica, Rehmannia, motherwort, etc. and probiotics) in the basal diet, respectively. The pre-test period was 7 days, and the formal test period was 21 days. The results showed that the feed to egg ratio of the F1-2 group was significantly lower than that of the CK group ( P<0.05), and the Huff unit, egg shape index, and eggshell thickness of eggs have all been improved. Compared with the CK group, the serum levels of progesterone (P4) and luteinizing hormone (LH) of laying hens in the F1-2 group increased by 77.20% and 58.02%, respectively (P<0.05). Compared with the CK group, the serum IL-2 content of laying hens in the F1-2 group, F2-1 group and F2-2 group was decreased by 24.54%, 29.88% and 27.25% (P<0.05), and the serum IgG content of laying hens in the F1-2 group was increased by 19.64% (P<0.05). The study indicates that two different Chinese herbal-probiotics compounds can improve the production performance and egg quality of laying hens, promote the secretion of ovarian reproductive hormones, improve the ovarian function, reduce the inflammatory reaction in laying hens, and improve immunity, and the effect of adding 2‰ Chinese herbalprobiotics compound 1 is better. [ABSTRACT FROM AUTHOR]

This researchers focused at how adding vitamin C (VC) to biochar and replacing it with a mineral supplement affected egg quality and laying hen performance. 50 experimental units were created from 400 laying hens using a 5 × 2 factorial treatment design (10 treatments, 5 repeats, and 8 laying hens per repetition). Biochar levels (0, 25, 50, 75, and 100% replacement with mineral supplements of diet) and VC levels (0 and 100 mg/kg of diet) were some of the studied variables. The results showed that different experimental diets had no significant effect on performance parameters (feed intake, feed conversion ratio, daily weight gain, egg weight, egg production, and egg mass) of laying hens. In the whole of experiment (50–62 weeks of age), dietary treatments had no influence on egg albumen %, Haugh unit, albumen index, yolk %, yolk index, yolk color, egg shell thickness, or egg shell ash. The results revealed that biochar, due to its availability and easy production, can replace mineral supplements in laying hens' diet, with no adverse effects on productive performance and egg quality traits. [ABSTRACT FROM AUTHOR]

1. This study investigated the effects of lysolecithins (LL) on performance, egg quality, blood profiles, relative organ weight and liver histopathology in laying hens. 2. A total of 480 healthy 65-week-old Lohmann laying hens were randomly allocated into four treatments in a 2 × 2 factorial arrangement design with two levels of energy (AMEn, 11.08 MJ/kg and 12.94 MJ/kg) and two levels of LL (0 and 0.05%). 3. Birds fed high energy diets had lower (P < 0.05) average daily intake and feed conversion rate during weeks 0–4, 5-8 and 0–8, but higher (P < 0.05) average egg weight (AEW) during trial weeks 0–4. There was an interaction in (P < 0.05) AEW during trial weeks 0–14 and 0–8 for energy and LL. The high energy diets increased yolk colour at the end of weeks 2 and 4, while addition of LL increased albumen height at the end of week 2. There was an interaction (P < 0.05) in yolk colour between energy and LL at the end of week 2. There was an interaction (P < 0.05) in serum superoxide dismutase and LDL-C throughout the experiment. 4. The high energy diets increased (P < 0.05) the relative weight of abdominal fat compared with low energy diets. The high energy diets increased (P < 0.05) liver ether extract content and liver pathological injury score compared with low energy diets at the end of week 8, while the addition of LL decreased (P < 0.05) liver pathological injury score. 5. The supplementation of LL in high energy diets could alleviate some negative effects on liver injury in late laying hens. [ABSTRACT FROM AUTHOR]

A meta-analysis was conducted to determine the effects of different types of oligosaccharides (OS) on the egg quality, intestinal profile, nutrient digestibility, and immunity of laying hens. A dataset was constructed from articles published between 2006 and 2023 via a literature search using several keywords related to oligosaccharides and laying hens' performance. After careful evaluation, the final dataset was developed from 25 in vivo studies comprising 165 comparisons. The meta-regression showed that levels of OS supplementation curvilinearly increased (p < 0.05) hen day egg production (HDEP), and crude protein digestibility (CPD). However, OS supplementation did not affect (p > 0.05) feed intake (FI), feed conversion ratio (FCR), egg mass, egg weight, eggshell thickness, shell strength, and Haugh unit. OS supplementation showed a positively improved antioxidant activity, as indicated by the curvilinear effect on superoxide dismutase (SOD) and malondialdehyde (MDA) concentration. In the categorical meta-analysis, mannan oligosaccharide (MOS), xylooligosaccharides (XOS), and chitosan oligosaccharide (COS) significantly increased (p < 0.01) HDEP and CPD. MOS was the only type of OS that decreased (p < 0.05) FCR while FOS showed to increase (p < 0.01) Haugh unit. To sum up, oligosaccharides could generally increase HDEP but MOS is superior to improving HDEP and FCR while FOS is better than other OS to increase eggshell thickness. Oligosaccharides increase egg production and protein digestibility in laying hens. Mannan oligosaccharide improves feed conversion ratio in laying hens. Elevated trends of IgG and IgA after supplementation with oligosaccharides. Fructo-oligosaccharides improve eggshell thickness and suppress Malondialdehyde (MDA) in laying hens. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of Bacillus coagulans (B. coagulans) on the productive performance, egg quality, blood biochemistry, antioxidant capacity, reproductive hormones, immune function, and intestinal morphology of laying hens (86 weeks old) during the late laying period. A total of 960 Hy-Line Brown layers were randomly assigned to five treatment groups, each with 6 replicates of 32 hens. Hens were grouped as follows: basal diet (control group) and a basal diet supplemented with 3.25 × 105, 6.5 × 105, 9.75 × 105, or 1.3 × 106 cfu/g B. coagulans. Dietary supplementation with B. coagulans significantly enhanced egg mass, egg weight, and laying rate and decreased the feed conversion ratio (FCR) in comparison with the control group. No significant difference was observed in the feed intake, breaking rate, albumen height, haugh unit, egg yolk colour, eggshell strength, and eggshell thickness among all groups. The serum total protein (TP) levels of laying hens fed 6.5 × 105 cfu/g B. coagulans were higher than those of laying hens in the control group. Dietary supplementation with 3.25 × 105 cfu/g and 6.5 × 105 cfu/g B. coagulans improved the activity of glutathione peroxide (GSH-Px) compared with that of the control group. The serum IgA concentration of laying hens in the 1.3 × 106 cfu/g B. coagulans treatment group was higher than that of the control. In the ileum, 6.5 × 105 cfu/g B. coagulans supplementation significantly increased the ratio of villus height to crypt depth (VH/CD) compared to that of the control group. It can be concluded that B. coagulans, at a supplementation level of 6.5 × 105 cfu/g feed, can be used as an effective feed additive to improve the production performance of laying hens during the late laying period by increasing the serum TP level, serum GSH-Px activity, and ileal VH/CD ratio. Bacillus coagulans improved the productive performance of laying hens during the late laying period. Inclusion of Bacillus coagulans in the diet might benefit laying hens' health by improving blood biochemistry, enhancing antioxidant activity and intestinal morphology, and slightly enhancing immune ability. The optimum concentration of Bacillus coagulans as a supplement to the basal diet to promote production performance and improve host health is 6.5 × 105 cfu/g. [ABSTRACT FROM AUTHOR]

The purpose of the experiment was to investigate the effect of GSE on the production performance, egg quality and serum biochemical indexes of laying hens in the late peak egg laying period. A total of five hundred and forty 53-week-old Jingfen No. 2 laying hens with similar weight, egg production rate and good health were randomly divided into three groups, with six replicates in each group and 30 laying hens in each replicate. The laying hens in group A were fed a basal diet, and GSE was added 200 and 300 mg/kg to the basal diet of group B and group C, respectively. The pre-test period was seven days and the positive trial period was 42 days. The results showed that compared with group A, the average egg weight of the group C was significantly increased (P<0.05), the egg qualification rate of the group B was significantly increased (P<0.05), the eggshell strength of the group B and group C was significantly increased (P<0.05), the protein height of the group C was significantly increased (P<0.05), the serum total protein content of the laying hens in the group B increased significantly (P<0.05), the serum high density lipoprotein content of the laying hens in the group C (P<0.05), and the serum IgA content of laying hens in the group C was significantly increased (P<0.05). The study indicates that adding GSE to the diet of laying hens in the late peak egg laying period can improve eggshell strength and egg qualification rate, reduce the feed to egg ratio, improve immune function, and increase the economic benefits of breeding, and the effect of adding 300 mg/kg GSE is obvious. [ABSTRACT FROM AUTHOR]

Abstract Orychophragmus violaceus (OV) and chicory (Cichorium intybus L., CC) can be used as fresh or dry forage for animals. To determine whether OV and/or CC have beneficial effects on performance and egg quality, a total of 1212 28-wk-old Beijing You Chicken (BYC) laying hens with similar performance were randomly allocated to 4 groups with 3 replicate pens per group, and 101 birds per pen. The birds were fed a basal diet (control), the basal diet + OV (3.507 kg/d/pen), the basal diet + CC (2.525 kg/d/pen), and the basal diet + OV + CC (OVC, 1.7535 kg/d/pen OV + 1.2625 kg/d/pen CC) for 3 wks after one wk of adaptation. The results showed that egg-laying rate was not affected by OV, CC and OVC (p > 0.05), but weekly average egg mass was significantly increased by OV and CC (p < 0.05). The feed egg ratio in the CC group (2.82) was significantly lower than that in the other three groups (p < 0.05). The eggshell thickness (EST), albumen height (AH) and Haugh unit (HU) were decreased by OV and CC (p < 0.05); while yolk color (YC) was increased in the CC and OVC groups (p < 0.05). Egg grade was decreased by OV (p < 0.05). Sensory evaluation showed that there was a trend for increased YC in OV, CC and OVC (p = 0.089). Serum total protein was significantly lower in OV group than those in the control and CC group (p < 0.05); serum albumin content was significantly decreased in OV, CC and OVC groups (p = 0.006). Serum glutathione peroxidase activity in CC and OVC groups was significantly higher than that in the control group (p < 0.05). In conclusion, the present study suggests that CC had a better effect on the performance of the native laying hens than OV. The OV and CC affected egg quality, while YC was increased in CC and OVC groups. The OVC improved YC and serum antioxidative properties of native laying hens without affecting the performance. [ABSTRACT FROM AUTHOR]

[Objective] To study the application of black solidier fly larvae in layer production. [Method] Hy-line grey laying hens were supplemented with different forms of the larvae to study the effects of laying performance and egg quality. A total of one hundred and ninety-two 300- day-old Hy-line grey laying hens with similar healthy and laying rate were randomly divided into 4 groups with 3 replicates per group and 16 hens per replicate. The hens in the control group were fed basal dietⅠ, and those in the experimental groups Ⅰ, Ⅱ and Ⅲ were fed the basal diet Ⅱ added with 1 136 g/ d live larvaes, 1 136 g/ d frozen larvaes and 366 g/ d dried larvaes, respectively. The pre-trial period lasted for 10 days, and the trial period lasted for 60 days. [Result] The results showed as follows: The egg number in experimental groups Ⅰ and Ⅲ was lower than that in control group, but the egg number in experimental group Ⅱ was increased, and the difference between groups was not significant (P>0. 05). Total feed intake, feed to egg ratio and average daily feed intake in experimental groups Ⅰ and Ⅱ were significantly higher than those in control group (P<0. 05), but there was no significant difference between experimental group Ⅲ and control group (P>0. 05). The rate of broken eggs in the experimental groups was lower than that in the control group, and that in the experimental group Ⅱ was significantly lower than that in the control group (P<0. 05), but there was no significant difference in other groups (P>0. 05). Supplementation with different forms of black soldier fly larvae could improve egg yolk color, but had no significant effect on egg shape index (P>0. 05). The egg Haugh unit in experimental group Ⅲ was extremly significantly higher than that in control group (P<0. 01), and the egg Haugh unit in experimental group Ⅰ and Ⅱ was significantly higher than that in control group (P<0. 05). The eggshell thickness in control group was the thinnest, which was extremly significantly lower than that in experimental group Ⅲ (P<0. 01). The yolk proportion in control group was higher than that in experimental groups, significantly higher than that in experimental group Ⅲ (P<0. 05). [Conclusion] Supplementary feeding of different forms of black soldier fly larvae (live, frozen and dried) all can reduce the rate of broken eggs and improve the egg quality. It is of great significance to feeding of black soldier fly larvae as protein feed. [ABSTRACT FROM AUTHOR]

[Objectives]The purpose of this study was to investigate the effects of synbiotic on laying performance, antioxidant capacity, intestinal function, and egg quality of laying hens. [Methods]A number of 192 420-day-old Hy-line brown hens were divided into 2 groups with 6 replicates per group and 16 hens each replicate. Birds in the control (Con) group were fed a basal diet, and the synbiotic (Syn) group was fed a basal diet supplemented with 1 000 mg·kg-1synbiotic. The experiment lasted for 60 days. [Results]Compared with the Con group, Syn group significantly increased laying rate (P＜0.05),the contents of serum albumin and high-density lipoprotein cholesterol (P＜0.05),and serum total antioxidant capacity (T-AOC) and liver T-AOC and total superoxide dismutase (T-SOD) activity as well as jejunal mucosal T-SOD activity (P＜0.05) . Compared with the Con group, Syn group significantly increased the contents of immunoglobulin G and secretory immunoglobulin A in jejunual mucosa and immunoglobulin M in ileal mucosa (P＜0.05),and it decreased tumor necrosis factor α content in jejunal mucosa (P＜0.05) . Compared with the Con group, Syn group did not alter muscle thickness, villus height, crypt depth or the villus height/crypt depth in jejunum and ileum (P＞0.05),while the Haugh unit significantly increased in Syn group (P＜0.05) . [Conclusions]Adding 1 000 mg·kg-1synbiotic in the diet of laying hens could improve the antioxidant capacity and intestinal function of laying hens, resulting in the improved production performance and egg quality. [ABSTRACT FROM AUTHOR]

Simple Summary: Taurine is a necessary amino acid for human health, while cysteamine is an intermediate metabolite to the synthesis of taurine. This study investigated effects of dietary cysteamine supplementation on the egg taurine deposition efficiency, egg quality, production performance and ovary development in laying hens. The results of this study indicate that cysteamine supplementation benefits yolk taurine deposition in both peak and late stages of egg production, but hens at the late stage of egg production showed depressed production performance and egg quality. The present study revealed that laying hens at the peak stage of egg production are suitable for cysteamine diets to produce high-taurine eggs. This study aimed to examine the effect of dietary cysteamine on yolk taurine content in hens during different egg production periods. In Exp. 1, China Agricultural University-3 (CAU-3) hens at the peak stage of egg production (aged 31 wks) were used to explore the effect of diets supplemented with 0.1% cysteamine on yolk taurine content, egg quality and production performance. In Exp.2, two breeds of hens (half Hy-Line Brown and half CAU-3 hens) at the late stage of egg production (68 wks) were used to investigate the influence of diets supplemented with 0, 0.02%, 0.04%, 0.08% or 0.10% cysteamine on yolk taurine content, egg quality, production performance and ovary development. In Exp.1, diets supplemented with 0.1% cysteamine significantly increased yolk taurine content (p < 0.05) without negative influence on production performance or egg quality. In Exp.2, the highest yolk taurine content was observed when cysteamine was supplemented at 0.08% (p < 0.001). However, supplemental cysteamine linearly or quadratically decreased production performance over the first few weeks of feeding, and the effects disappeared with continued feeding (p < 0.05). In conclusion, this study indicated that cysteamine supplementation benefits yolk taurine deposition in hens at both peak and late stage of egg production, but hens at the late stage of egg production show depressed production performance and egg quality. [ABSTRACT FROM AUTHOR]

The experiment was to study the effect of Rhizoma anemarrhenae and Astragalus crude extract on laying performance, egg quality and antioxidant function of laying hens. A total of 1 200 Esha brown laying hens with similar body weight were randomly divided into four treatment groups. Laying hens in each group were fed with the same diet, the test groups added 1.0, 1.5 and 2.0 mL/kg of Rhizoma anemarrhenae and Astragalus crude extract in drinking water, respectively, and the control group did not add Rhizoma anemarrhenae and Astragalus crude extract in drinking water. Pre-feeding lasted for 1 w, and the formal experiment lasted for 4 w. The results showed that compared with control group, the laying rate and average egg weight of laying hens in test group 2 and group 3 were significantly increased (P<0.05), the death and culling rate of laying hens added Rhizoma anemarrhenae and Astragalus crude extract groups was significantly decreased (P<0.05), and the feed to egg ratio and egg breakage rate of laying hens in test group 2 and group 3 were significantly decreased (P<0.05). Compared with control group, the haugh unit of eggs in test group 2 and group 3 was significantly increased (P<0.05), the eggshell strength and thickness of eggs in all Rhizoma anemarrhenae and Astragalus crude extract groups were improved (P<0.05), and the egg weight and egg white weight of eggs were significantly increased (P<0.05). Compared with control group, serum malondialdehyde was significantly decreased in Rhizoma anemarrhenae and Astragalus crude extract group (P<0.05), serum total antioxidant capacity of laying hens in test group 2 and group 3 were significantly increased (P<0.05). The activity of catalase, superoxide dismutase and glutathione peroxidase were significantly increased (P<0.05), while the concentration of hydrogen peroxide was significantly decreased (P<0.05). The study indicates that adding 1.5 and 2.0 mL/kg Rhizoma anemarrhenae and Astragalus crude extract to drinking water can improve the laying performance and egg quality, and enhance the antioxidant capacity of laying hens. It is recommended to use 1.5 mL/kg Rhizoma anemarrhenae and Astragalus crude extract in breeding. [ABSTRACT FROM AUTHOR]

Background: Toward the late phase of laying, the production performance of laying hens decreases, egg quality deteriorates, lipid metabolism weakens, and hepatic lipid accumulation is exacerbated. Probiotics as an alternative to antimicrobials have been employed in poultry-related industries. Lactobacillus rhamnosus GG (LGG) is currently the most researched and clinically validated probiotic, showing promising effects in multiple application areas. However, few studies have been conducted on livestock (including poultry) production. Results: Compared with the CON group, the feed conversion ratio (P < 0.01) declined significantly in the LGG group. Eggshell strength (P < 0.001) and eggshell thickness (P < 0.001) were significantly increased by supplementation with LGG in the diet. The height (P < 0.001) and proportion (P < 0.05) of the effective layer and the mammillary knob density (P < 0.01) in the eggshell ultrastructure of the LGG group increased significantly, while the mammillary layer (P < 0.05) and knob width (P < 0.01) decreased significantly. The LGG-treated hens had significantly lower serum concentrations of low-density lipoprotein (P < 0.05), free fatty acids (P < 0.01), and liver triglyceride (P < 0.05) levels than those in the CON group. Conclusions: LGG supplementation significantly decreases the feed conversion ratio, improves eggshell quality by altering the ultrastructure, and improves lipid metabolism in the late laying period. [ABSTRACT FROM AUTHOR]

To explore the effect of Eucommia ulmoides bark powder on production performance, oxidation resistance and intestinal flora of laying hens, 288 280-day-old Dawu Jinfeng laying hens were randomly divided into four groups, blank control group, 1% respectively eucommia skin eucommia ulmoides powder add group (group 1%), 3% skin eucommia ulmoides powder add group (group 3%) and 5% leather powder add group (group 5%), Feeding for 63 days was a 7-day pre-trial period and an 56-day trial period. At the beginning of the pre-trial period, laying hens were fed the normal full feed and gradually replaced with the experimental diet for the following 7 days. Statistical laying performance of laying hens, after the experiment, eggs, serum, liver, oviduct, ovary and ileum were collected for egg quality detection, antioxidant capacity detection and intestinal flora determination. The results showed that dietary eucommia ulmoides skin powder increased laying rate (P>0.05), increased total antioxidant capacity, decreased the content of malondialdehyde (P<0.05), and decreas`ed the number of v [ABSTRACT FROM AUTHOR]

Context: The nutritional value of enzyme‐supplemented wheat‐contained diets can be influenced by interactions between wheat cultivar and exogenous enzyme, which in turn cause various effects on the performance of poultry. Aims: The effects of diets including various wheat cultivars with or without enzyme on productive performance and egg quality characteristics were evaluated. Methods: A total of 270 58‐week‐old Lohmann LSL‐Lite were allocated to 9 experimental dietary groups with 5 replicate cages and 6 birds per each cage. Based on a 4 × 2 factorial arrangement of treatment, nine iso‐caloric and iso‐nitrogenous experimental diets, including four wheat cultivars (Sardari, Azar 2, Pishgam and Sirvan) with and without enzymes plus a corn‐based control diet, were tested in a completely randomized design during an 8‐week trial period. Key results: From weeks 58 to 63 and 63 to 67 of age, the hens fed with Sardari‐included diet showed the lowest feed intake compared to other groups (p < 0.05). Egg production (EP), feed conversion ratio (FCR) and egg mass (EM) were not influenced by the experimental diets. At the age of 62 weeks, the effect of adding enzyme on egg shape index was significant. Moreover, in sampling week 67, increased eggshell weight (%) was detected in enzyme‐supplemented diets compared to diets with no enzyme (10.03 vs. 9.37, respectively). Besides, the shell thickness was the highest in the group fed with Azar 2, and the lowest in the group fed with Sirvan at the age of 67 weeks (p < 0.05). Albumen weights (%) were also significant in some cases. The highest albumen weight was observed in Sirvan‐included diet without enzyme on week 62. Reduced yolk weight was detected in enzyme‐supplemented Pishgam‐included diet on 62 weeks of age (p < 0.05). Conclusions: The inclusion of the diets of laying hens with the four tested Iranian wheat cultivars has no negative impact on most productive performance and egg quality indices. Moreover, supplementing the wheat‐included diets with non‐starch polysaccharidase enzyme (beta‐endopower) improved eggshell weight on week 67. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to investigate the effect of adding composite probiotics to the diet on production performance, egg quality, serum immunological indexes and intestinal flora of Hyline brown laying hens. A total of 400 healthy 42-week-old Hyline brown laying hens with similar body weight and laying rate were randomly divided into four groups, with five replicates in each group and 20 hens in each replicate. Laying hens in control group were fed with basic diet, and laying hens in group Ⅰ, group Ⅱ and group Ⅲ were fed with basic diets supplement with 0.5%, 1.0% and 1.5% compound probiotics, respectively. The trial period lasted for 42 d. The results showed that compared with control group, the average daily feed intake and feed to egg ratio of laying hens in three experimental groups were significantly decreased ( P<0.05). Compared with group Ⅰ, the feed to egg ratio of group Ⅱ and group Ⅲ was significantly decreased ( P<0.05). The eggshell strength and yolk specific gravity of three experimental groups were significantly higher than that of control group ( P<0.05). The serum IgG content of laying hens in three experimental groups was significantly higher than that of control group ( P<0.05), the serum IgG content of group Ⅱ and group Ⅲ was significantly higher than that of group Ⅰ ( P<0.05), and the serum content TNF-α of laying hens in three experimental groups was significantly lower than that of control group ( P<0.05). The number of lactic acid bacteria in the caecum of laying hens in three experimental groups was significantly increased compared to control group ( P<0.05), the number of lactic acid bacteria of laying hens in group Ⅱ and group Ⅲ was significantly increased compared to group Ⅰ ( P<0.05), and the number of lactic acid bacteria of laying hens in group Ⅲ was significantly increased compared to group Ⅱ ( P<0.05). The number of Escherichia coli andSalmonella in the caecum of laying hens in three experimental groups was significantly decreased compared to control group ( P<0.05). Compared with group Ⅰ, the number of Escherichia coli of group Ⅱ and group Ⅲ was significantly decreased ( P<0.05). The study indicates that the compound probiotics can effectively improve production performance, egg quality and intestinal health, enhance immune function of Hyline brown laying hens. The dosage of compound probiotics is 1.5%. [ABSTRACT FROM AUTHOR]

This study was carried out to determine the effect of adding different ratios of dandelion (Taraxacum officinale) extract (KHE) to layer hen rations on performance and egg internal-external quality parameters. In the study, 96 layer Atak-S hens at the age of 22 weeks were used. Chickens were divided into 4 groups, each consisting of six subgroups, and arranged in a way to have four chickens in each subgroup. The study was conducted over a period of 90 days. During the study, the control group was fed with basal feed, and the experimental groups were fed with feeds with 0.30%, 0.60% and 0.90% KHE added to the basal feed, respectively. Although there was no significant difference between the groups in terms of egg production (P>0.05), it was determined that the average egg production at the end of the study was numerically higher in the groups fed with KHE-containing feeds compared to the control group. There was no significant difference between the groups in terms of feed consumption, feed conversion ratio, live weight, egg yolk colour averages (P>0.05). In the study, it was determined that egg weight in the groups containing 0.90% KHE was significantly higher than the control group (P<0.05). Egg shell thickness were also significantly increased in 0.30% and 0.60% KHE containing groups (P<0.05). It was concluded that dandelion extract has a positive effect on egg quality in laying hens and more studies should be done on this subject. [ABSTRACT FROM AUTHOR]

The experiment was to study the effect of selenium yeast supplementation on production performance, egg quality, blood routine and antioxidant function of laying hens in late laying period. A total of three hundred and sixty 420-day-old laying hens were randomly divided into four groups, with three replicates in each group and 30 laying hens in each replicate. Laying hens in control group were fed with a basal diet, and hens in experimental group Ⅰ, group Ⅱ and group Ⅲ were fed with basal diet supplemented with 0.1%, 0.2% and 0.3% selenium yeast, respectively. The experiment lasted for 60 d. The results showed that compared with control group, the eggshell thickness of group Ⅰ, group Ⅱ and group Ⅲ was extremely decreased (P<0.01). The number of platelets in blood of laying hens in group Ⅱ and the mean corpus-cell hemoglobin content in blood of laying hens in group Ⅲ were significantly decreased (P<0.05). The white blood cells of laying hens in group Ⅱ, and the MCH of laying hens in group Ⅱ and group Ⅲ were extremely decreased (P<0.01). The mean red blood cell volume of laying hens in group Ⅰ and group Ⅱ was significantly increased (P<0.05). The content of total superoxide dismutase and hydroxyl radical in serum of laying hens in group Ⅰ were extremely increased (P<0.01), and the activity of glutathione peroxidase in serum of laying hens in experimental groups was extremely increased (P<0.01). Serum malondialdehyde of laying hens in group Ⅰ was significantly decreased (P<0.05). The experiment indicates that adding selenium yeast to diet can maintain blood homeostasis and stable redox of laying hens, and alleviate the damage caused by high temperature in summer, the supplementation of 0.1% selenium yeast has better effect. [ABSTRACT FROM AUTHOR]

Background: Eggshell speckle phenotype is an important trait in poultry production because they affect eggshell quality. However, the genetic architecture of speckled eggshells remains unclear. In this study, we determined the heritability of eggshell speckles and conducted a genome-wide association study (GWAS) on purebred Rhode Island Red (RIR) hens at 28 weeks to detect potential genomic loci and candidate genes associated with eggshell speckles. Results: The heritability of eggshell speckles was 0.35 at 28 weeks, and the speckle level is not related to other eggshell quality traits in terms of phenotypic correlation. We detected 311 SNPs (6 significantly, and 305 suggestively associated) and 39 candidate genes associated with eggshell speckles. Based on the pathway analysis, the 39 candidate genes were mainly involved in alpha-linolenic acid metabolism, linoleic acid metabolism, ether lipid metabolism, GnRH signaling pathway, vascular smooth muscle contraction, and MAPK signaling pathway. Ultimately, ten genes, LOC423226, SPTBN5, EHD4, LOC77155, TYRO3, ITPKA, DLL4, PLA2G4B, PLA2G4EL5, and PLA2G4EL6 were considered the most promising genes associated with eggshell speckles that were implicated in immunoregulation, calcium transport, and phospholipid metabolism, while its function in laying hens requires further studies. Conclusions: This study provides new insights into understanding the genetic basis of eggshell speckles and has practical application value for the genetic improvement of eggshell quality. [ABSTRACT FROM AUTHOR]

Simple Summary: Dietary supplementation with Chinese herbal feed-additives benefits the high production performance of laying hens. Considering that the effects of the Chinese herbal formulation on animal production differ, appropriate formulation may have additive effects. Therefore, this study investigated effects of the traditional Chinese herbal feed-additive prepared from specific Chinese herbs on production performance, egg quality, antioxidant capacity, immunity, and intestinal health of laying hens. The results of this study indicate that dietary supplementation with the traditional Chinese herbal feed-additive can effectively improve production performance, egg quality, antioxidant capacity, immunity, and intestinal health. The results revealed that the traditional Chinese herbal feed additive is an effective alternative to antibiotics in an antibiotic-free farming environment. 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. [ABSTRACT FROM AUTHOR]

This study was aimed at investigating the effects of non-fasting moulting treatment and extended cold storage on table egg quality traits of a commercial white layer hen. For this research, 360 eggs were collected from moulted and non-moulted flock four weeks after the end of the moulting program. The hens in each group were allowed ad libitum access to water and their respective diets as grain barley for the moulting group and standard layer feed for the control group during the moulting period of 10 days and then a complete layer ration after the moulting program through the laying period. Sample eggs of each of these two groups were numbered, weighed and further assigned to a different storage period as daily fresh eggs: 15, 30, 45, 60 and 75 days. All eggs were stored between 4°C and 5°C and 55% and 60% relative humidity throughout the experiment. Egg weight, egg length, egg width, shell strength, shell weight, shell thickness, yolk height, yolk diameter, yolk colour, albumen height, albumen width, and albumen length were measured at each consecutive analysis period for egg quality comparison. Non-fast moulting treatment significantly affected egg weight, egg-width, egg length and breaking strength (P < 0.001, P < 0.001, P < 0.001 and P < 0.020). There were no significant effects of the length of a cold storage period on the external quality traits of egg weight, egg width, egg length and egg-shape index. Shell thickness and breaking strength of eggs were affected significantly (P < 0.001 and P < 0.02) by the length of a storage period. The yolk height and yolk colour scores were found to be significantly greater in eggs from the moulting group while all internal quality characteristics were significantly affected by the length of a storage period (P < 0.001). In conclusion, even if it was cold storage, egg quality tended to decline in the extended storage period and non-fasting moulting treatment improved the external and internal egg quality. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate the effect of grape marc flour addition to the laying hens' diet on their egg production, egg quality, total yolk lipids and yolk total fatty acid composition, cholesterol content in the yolk and blood serum as well as on the yolk lipid oxidation. An experiment was conducted with a total of 90 laying hens (at 40 weeks old) from Lohmann Classic Brown breed, randomly divided into three groups, 30 hens in each (3 replications x 10 layers per group). The diet of the experimental hens was supplemented with 1% and 3% of grape marc flour. The trial duration was 48 days. Grape marc flour addition to the laying hens' compound feed did not significantly (P > 0.05) affect their live body weight, egg production, egg morphological properties as well as total yolk lipids content, total cholesterol content in the yolk and blood serum and yolk fatty acids composition. However, the egg yolk malondialdehyde (MDA) level during egg storage for 30 days at room temperature significantly decreased (P < 0.01) in comparison with control eggs. The addition of grape marc flour has the potential to extend the shelf life of eggs. [ABSTRACT FROM AUTHOR]

Simple Summary: Orange pulp is an industrial byproduct that contains naturally active components, such as phenolic acids and flavonoids. Therefore, the objectives of this trial were to demonstrate the effects of dietary dried orange pulp (DOP) on the laying performance, egg quality, oxidative stability, yolk fatty acid profile, serum biochemistry, and reproductive tract morphology of laying hens. The body weight gain, feed intake, egg production, egg weight, egg mass, and feed conversion ratio of laying hens fed the DOP diets were greater than those fed the control diet. Eggs obtained from the DOP groups had a heavier shell weight, shell thickness, and greater yolk color score. Dietary DOP enhanced the egg yolk proportions of beneficial fatty acids, whereas the contents of yolk saturated fatty acids, cholesterol, and triglycerides were decreased. After storage for 40 days, the eggs obtained from the DOP hens had a better antioxidant capacity and lower lipid peroxidation rate. The ovary, oviduct, uterus, and follicle weights of hens receiving diets containing DOP were heavier than those of the control hens. In conclusion, dietary DOP up to 100 g/kg of feed improves the laying performance, health status, antioxidant capacity, egg nutritive value, and egg shelf life in 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 (DOP5%), a basal diet containing 70 g DOP/kg feed (DOP7%), and a basal diet containing 100 g DOP/kg feed (DOP10%). 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 DOP7% and DOP10% diets were greater (p < 0.01) than those fed the control diet. Eggs obtained from the DOP7% and DOP10% 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 DOP7% and DOP10% 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. [ABSTRACT FROM AUTHOR]

The present study was conducted to determine the effects of a dietary probiotic (Bifidobacterium animalis ssp.) as a substitute to a mixture of growth-promoting antibiotics (zinc bacitracin and colistin sulfate on the laying performance, egg quality characteristics, blood parameters, and organ morphological characteristics of early-phase laying hens. Seventy-two (72) 20-week-old Lohmann White hens were randomized into three treatment groups. The dietary treatments are as follows: Growth-promoting antibiotics (GPA; 0.5 % of COLI-ZIN), probiotic (PRO; 0.1% Bifidobacterium animalis ssp. lactis) or without any additive (control; CON) for 90-days feeding trial. Significant differences were observed in feed intake and feed conversion ratio of the bird's fed PRO compared to GPA and CON at 90 days of the experimental period. The air cell height, yolk volume, and yellowness of yolk color were lower, and thick and thin albumen diameters were the greatest in the PRO group than in CON and GPA groups (P<0.05). Dietary PRO decreased the number of heterophils (H) and increased the number of lymphocytes (L), improving the H:L index (P<0.05). Probiotic treatment increased crop and duodenum relative weight compared to GPA (P<0.05). No significant changes (P>0.05) were observed in the relative weight of reproductive organs. This study shows that the dietary supplementation of 0.1% Bifidobacterium animalis improves laying performance and egg traits and can be a substitute for antibiotics in hen diets. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the physical, chemical, and microbiological properties of applying an antibacterial water filter made from zeolite composites in laying hens. This study used a completely randomized design with a factorial pattern with 2 factors and 3 replications for egg quality. Factor A is the zeolite treatment, and factor B is the day of egg collection after being filtered. If the measures show a significant difference, it is continued with the least significant difference test, and the chemical quality of the eggs and the microbiology of the eggs are tested using the t-test analysis (paired samples). The results showed that there was a significant interaction between the zeolite treatment and the day after the filter was installed after the eggs were collected. This increases the value of egg length, egg width, shell weight, shell thickness, and haugh units. Furthermore, the chemical quality of eggs treated with zeolite alone on day 3 had a significant effect (P<0.05) on the dry matter and egg fat content . The microbiological quality of the eggs also showed that the zeolite treatment reduced the TPC value and effectively killed Escherichia coli and Salmonella sp. It was concluded that the application of zeolite filters to the drinking water of laying hens could improve physical quality, maintain chemical quality, and is effective as an antibacterial against bacterial populations, Escherichia coli and Salmonella sp bacteria in eggs. [ABSTRACT FROM AUTHOR]

Vitamin D3 has an integral part in calcium and phosphorus homoeostasis, which in turn plays a key role in egg production of hens. The present study aimed to investigate whether an additional vitamin D3 supplementation improves the laying performance and egg quality of hens according to their genetic potential. For this purpose, four layer lines (low performing: R11 and L68; high performing: WLA and BLA) supplemented either with 300 or 3000 IU vitamin D3 per kg feed were compared concerning serum 25-hydroxyvitamin D3 (25-OHD3), calcium, phosphorus and alkaline phosphatase (ALP), laying performance and egg quality. The higher supplementation of vitamin D3 increased 25-OHD3 serum concentrations in all genotypes, except for R11 and WLA hens in week 49, and also elevated vitamin D3 and 25-OHD3 content in the egg yolk (p < 0.05). In week 29, 3000 IU vitamin D3 decreased pooled least squares means (LSMeans) of serum calcium concentrations considering all genotypes and increased the ALP concentrations in BLA hens (p < 0.05). Considering the whole experimental period daily egg mass of R11 hens was increased by an additional vitamin D3 supplementation (p < 0.001). Regarding all genotypes and the whole experimental period the pooled LSMeans of breaking strength of eggs from hens fed 3000 IU vitamin D3 were higher than those of hens fed 300 IU (p = 0.044). In conclusion, present results give evidence that the higher vitamin D3 supplementation might have genotype-dependently beneficial effects on calcium and phosphorus homoeostasis of hens, which might improve feed efficiency in the early laying period and promote the persistence of the laying period irrespectively of genotype. The increase of serum 25-OHD3 by the higher vitamin D supplementation supported the higher transfer of vitamin D in the egg yolk and improved genotype-dependently the breaking strength of the eggshell. [ABSTRACT FROM AUTHOR]

The experiment was to investigate effect of Eucommia ulmoides Oliv leaves powder on production performance, egg quality, serum biochemical indexes and yolk cholesterol of Hyline brown laying hens. A total of 720 Hyline brown laying hens reared at 327 d of age were randomly divided into five groups, with four replicates in each group and 36 laying hens in each replicate. The hens in control group were fed with basic diet, the hens in experiment groups were fed with 0.5%, 1.0% and 1.5% Eucommia ulmoides Oliv leaves powder in basic diet respectively. The pre-experiment period was 1 w, and formal experiment period was 7 w. The results showed that the laying rate of laying hens in 1.0% group and 1.5% group were significantly higher than that of control group (P<0.05). The eggs yolk color in 1% group was significantly higher than that of control group (P<0.05). The content of TC of laying eggs in control group was significantly higher than that in 1.0% group and 1.5% group (P<0.05). The T-AOC and CAT activity of laying hens in each experiment group were significantly higher than those in control group (P<0.05). The content of egg yolk cholesterol of laying hens in 1.0% group and 1.5% group were significantly lower than that in control group (P<0.05). The experiment indicates that adding Eucommia ulmoides Oliv leaves owder in diet can improve laying rate and egg quality of laying hens, reduce content of serum total cholesterol and egg yolk cholesterol, improve antioxidant capacity, and recommended amount is 1.0%. [ABSTRACT FROM AUTHOR]

The experiment studied the effects of different levels of Rumex patientia spp. leaf powder inclusion in laying hens' diets on their physical parameters and yolk color intensity. The study was conducted on 168 Hy-line laying hens (30 weeks aged), assigned in 3 treatment groups (C, E1 and E2) and housed in an experimental hall equipped with Big Dutchman cages, placed on 3 tiers with digestibility cages (3 treatments × 28 replicates × 2 birds per cage). Feed and water were administrated ad-libitum. During the entire 5 weeks experimental period (one week of accommodation), performance parameters were recorded: average daily feed intake(g/day/hen), feed conversion rate (g feed/g egg), laying rate intensity (%) and average egg weight (g). Eggs yolk color is generated by carotenoids as a nutritional response, which depends on their amount, type, and ratio. One of the most important aspects in how consumers rate the quality of food is color. The experimental results demonstrated that an inclusion rate of 1.5% and 3% Rumex patientia species leaves powder improved the yolk color intensity without negative effects on production performances and egg quality parameters. [ABSTRACT FROM AUTHOR]

Food occupies a principal role in human life, having a major impact on health status and representing diverse characteristics that ensure valuable nutrient intake. Ensuring human nutrition has become one of the essential problems facing mankind, and quantity, quality and proper use of food have a major effect on the human body. Many raw materials and food products spoil easily, considerably shortening their shelf life. Extending the shelf-life of food is required to remove seasonal consumption, enlarge availability to the consumer and decrease losses in perishable food products, resorting to some procedures to preserve their properties. If natural antioxidants are used as alternatives for synthetic antioxidants, customer claims for food without damaging residual substances can be satisfied, and the poultry industry would benefit considerably. The principal objective of this review was to describe and under light the current situation regarding the role and importance of the use of antioxidant compounds obtained from natural sources in order to improve the nutritional qualities of eggs following their inclusion in the feed of laying hens. Data from bibliographic sources are analyzed and presented. The characteristics of a number of 9 plants with antioxidant potential are described with an emphasis on their characteristics, utilization, and possible effects on egg quality, performance, and health. [ABSTRACT FROM AUTHOR]

Simple Summary: In the agricultural sector, particularly the poultry industry, antibiotics have been used as feed additives to treat and prevent infections or to improve the growth, health, and welfare of chickens. Many nutritional alternative strategies, including natural ingredients, have been investigated for their role in improving gut health without any adverse effect on productivity. The possibility of using microalgae as a new source of nutrients and health additives in animal feed formulations has been increased. Therefore, the aim of this study was to determine the effect of dietary C. vulgaris or T. obliquus on the laying performance, egg quality, intestinal histology, immune characteristics, antioxidant status, and gut microbiome of the laying hen. A feeding trial was conducted to investigate the effect of dietary supplementation of Chlorella vulgaris (CV) or Tetradesmus obliquus (TO) on laying performance, egg quality, and gut health indicators of laying hens. A total of 144 Hy-Line Brown laying hens aged 21 weeks were randomly assigned to one of three dietary treatments with eight replicates of six hens. Dietary treatments were as follows: CON, basal diet; CV, basal diet + 5 g C. vulgaris/kg of diet; TO, basal diet + 5 g T. obliquus/kg of diet. The results showed that diets supplemented with CV or TO had insignificant effects on laying performance, egg quality (i.e., Haugh unit and eggshell strength and thickness), jejunal histology, cecal short-chain fatty acids, and antioxidant/immune markers in ileal mucosa samples of laying hens. Compared with the control group, the egg yolk color score was higher (p < 0.05) in laying hens fed on diets containing CV and TO, although the former was a more intense yellow than the latter. Small intestinal lamina propria cells were isolated using flow cytometry to examine the percentages of immune cell subpopulations. Dietary microalgae did not affect B cells or monocytes/macrophages but altered the percentage of CD4+ T cells and CD8− TCR γδ T cells. Collectively, diets supplemented with C. vulgaris or T. obliquus can improve egg yolk color and would modulate host immune development and competence in laying hens. [ABSTRACT FROM AUTHOR]

There has been a rapid increase in the world's output of main poultry products (meat and eggs). This reflects customer desire for these high‐quality and safe products and the comparatively low price. Recently, natural feed additives, plants and products have been increasingly popular in the poultry and livestock industries to maintain and improve their health and production. Polyphenols are a type of micronutrient that is plentiful in our diet. They are phytochemicals that have health benefits, notably cardiovascular, cognitive function, antioxidant, anti‐mutagenic, anti‐inflammatory, antistress, anti‐tumour, anti‐pathogen, detoxification, growth‐promoting and immunomodulating activities. On the other hand, excessive polyphenol levels have an unclear and sometimes negative impact on gastrointestinal tract health, nutrient digestion, digestive enzyme activity, vitamin, mineral absorption, laying hens performance and egg quality. As a result, this review illuminated polyphenols' various sources, classifications, biological activities, potential usage restrictions and effects on poultry, layer productivity and egg external and internal quality. [ABSTRACT FROM AUTHOR]

The experiment aims to investigate the effects of peanut skin on the production performance, egg quality, and serum antioxidant indicators of laying hens. A total of 4 000 Hailan brown laying hens with similar body condition and egg production rate 56 week-old divided into two groups, with four replicates in each group and 500 laying hens in each replicate. The pretest lasted for 7 d and the formal test lasted for 45 d. The control group of laying hens were fed a basic diet, while the experimental group of laying hens were supplemented with 3% peanut skin to replace some of the raw materials in the basic diet. The results showed that at 45 d of the experiment, the egg laying rate of the experimental group was 1.40% higher than that of the control group. During the experimental period, the egg breaking rate of the experimental group showed a decreasing trend, and at the end of the experiment, it decreased by 1.01% compared to the control group (P<0.05). During the entire experimental period, the feed to egg ratio of the experimental group decreased slightly compared to the control group. During the experimental period, the egg quality was improved, and the egg yolk color of the experimental group was darker than that of the control group (P<0.05). At 45 d of the experiment, the Roche color level of the egg yolk was 2.22 color levels higher than that of the control group, an increase of 29.80% (P<0.05). The experimental group showed an increasing trend in eggshell thickness and eggshell strength. At the end of the test, the activity of T-SOD and GSH-Px in the serum of the test group were 13.68% and 6.83% higher than those of the control group respectively (P<0.05). The T-AOC and CAT activity of the experimental group were increased by 56.45% and 41.10% respectively compared to the control group (P<0.05). The MDA content in the serum of the experimental group decreased by 27.70% compared to the control group (P<0.05). Research shows that peanut skin can be added as a feed ingredient for laying hens, which can improve their production performance and egg quality. [ABSTRACT FROM AUTHOR]

The purpose of the experiment was to study the feasibility of using the larvae and residues of Hermetia illucens transformed into pig dung as animal feed additives for laying hens. A total of 1 000~1 200 four-day-old Hermetia illucens were inoculated on surface of 1 000 kg of fresh pig manure, and the mixture of the worm body and the remaining residue (BFM) was dried and crushed, and its nutritional components were detected. A total of 216 270-day-old Beijing Red Brown laying hens were randomly divided into three groups, with three replicates in each group and 24 chickens in each replicate. The laying hens in control group were fed with a basic diet, and each experimental group added 5%, 15% and 25% BFM to the basic diet. The experimental period was 8 w. The results showed that 1 000 kg of pig manure with a water content of about 77% was dried and crushed after biotransformation by Hermetia illucens larvae, leaving 168 kg (water content 86 g/kg) of dry matter of biotransformation mixture. BFM nutritional analysis showed that the content of crude protein, crude fat, crude fiber and calcium of BFM were 205, 46, 131 and 26 g/kg, respectively, while the content of VB1, VB2 and VB6 were 30.4, 30.2 and 230.2 mg/kg, respectively, which were rich in trace elements and essential amino acids. The laying rate of group 1 was the highest, at 85.7%, and the average egg weight increased with the increase of BFM addition. The addition of BFM has a significant impact on egg yolk weight, protein weight, egg shape index, and eggshell thickness. Compared with control group, the serum TP content and SOD activity of group 2 were significantly increased ( P<0.05). The TC content in group 2 and group 3 was significantly reduced ( P<0.05), while the T-AOC and GSH content were significantly increased ( P<0.05). The activity of CAT in group 1 and group 2 significantly increased ( P<0.05), the content of MDA in each experimental group significantly decreased ( P<0.05). The study indicates that BFM can used as an animal feed additive in laying hens, with a suitable addition amount of 15%. [ABSTRACT FROM AUTHOR]