The impact of phytoestrogen source supplementation on reproductive performance, plasma profile, yolk fatty acids and antioxidative status in aged laying hens

The change of albumen quality during the laying cycle and its potential physiological and molecular basis of laying hens

To elucidate the regulatory mechanisms that impact variability in albumen quality of laying hens from the peak of lay to the late production phase. A 60-wk study was conducted on a cohort of 20,000 Hy-Line Brown laying hens from 20 to 80 wk old. Before commencement at 20 wk, the 10-wk-old hens were acclimatized for 10 wk. This study examined changes in albumen quality, serum, and liver antioxidant capacity, magnum morphology, and expression of albumen-protein-related genes in the magnum. To reduce sampling error, we collected eggs (n = 90) from pre-determined cages at every sampling point (5-wk intervals), and 8 hens were selected at 10-wk intervals for blood and tissue collection. Our findings revealed that age significantly affected most evaluated parameters. Albumen gel properties, including hardness, gumminess, and chewiness, increased significantly with age (P < 0.05). With the increasing of hens' age from 20 to 80 wk, the albumen proportion of eggs was decreased, but eggshell proportion, yolk proportion, thick albumen proportion, thick to thin ratio, thick albumen solid content, albumen height, Haugh units (HU), and yolk color were increased and then decreased (P < 0.05). Compared to hens aged 20 to 60 wk, the hens (70-80 wk) had significantly reduced total antioxidant capacity (TAC) and glutathione levels (GSH) in the liver and lower serum TAC and superoxide dismutase levels (SOD) (P < 0.05). The magnum mucosal folds were highest in 40 to 60 wk-old hens, and the luminal diameter increased with age (P < 0.05). In the magnum, the mRNA expression levels for OVA, CPE, and NUP205 increased significantly between 30 and 40 wk, while FBN1 expression was higher between 30 and 50 wk (P < 0.05). At 70 to 80 wk, the expression of BRCA2 was significantly downregulated (P < 0.05). Albumen height, thick albumen proportion with protein secretion-related genes, enhanced antioxidant function, and luminal diameter correlated positively. However, the thick-to-thin albumen ratio negatively correlated with BRCA2, downregulated in aged laying hens. We used principal component and cluster analysis to deduce albumen quality changes during 3 phases: 25 to 35, 40 to 55, and 60 to 80 wk. The decline in albumen quality in aging hens is linked with decreased antioxidant capacity, magnum health, and downregulation of key genes involved in protein synthesis and secretion. These findings emphasize critical albumen quality changes in laying hens and suggest molecular pathways underlying age-related albumen quality alterations.

Effect of Genistein and Glycitein on production performance, egg quality, antioxidant function, reproductive hormones and related-genes in pre-peak laying hens

Genistein (GEN) and Glycitein (GLY), are types of isoflavone extracted mainly from soy plants, although GEN is associated with stronger antioxidant and growth-promoting effects. The impact of dietary GEN and GLY on reproductive performance, egg quality, and bone quality were investigated in the study. Additionally, to explore the underlying mechanism of action, the serum hormone levels and reproductive-related genes were investigated. A total of 378 Hy-Line Brown laying hens (120 days old) were randomly allocated to 3 dietary groups (Control), (GLY, and GEN at 50 mg/kg respectively) for a period of 8 wk. Each treatment has 126 birds (7 replicates of 18 birds each). Results were analyzed in 2 phases: wk 1 to 4, and 5 to 8 of feeding trial. The results indicated that supplemental GEN significantly increased egg number, hen-day production (HDP), and egg mass during wk 1 to 4, whereas, both glycitein and genistein increased egg number, egg weight, egg mass, HDP and improved feed-egg-ratio during wk 5 to 8. Egg quality analysis revealed significant improvements in eggshell quality; gloss, thickness, strength, and albumen quality indices (albumen height, Haugh unit, thick albumen fraction) due to dietary treatments. Also, the tibia strength, Ca content in the tibia ash and bone mineral content, were significantly increased by the dietary treatments. Significant increases in the serum levels of E2, LH, FSH, T3, T4, and GH, and the activity of antioxidant enzymes; SOD, CAT, GSH while reducing the level of MDA, was notable with the treatments. Additionally, reproductive-related genes: ESR1, FSHR, PRLR, GNRH1 were significantly upregulated by the supplementation of GEN and GLY. The efficacy of GEN in relation to the evaluated parameters was superior to that of GLY. Conclusively, we speculate that the improvement on laying performance, egg quality and tibia quality may be related to promoting effect of isoflavones on calcium metabolism, antioxidant function, reproductive hormones and related genes. Therefore, supplemental GEN at a dosage level of 50 mg/kg, can be used to promote laying performance, sustain egg production and maintain the physiological function of young laying hens.

Effects of chlorogenic acid on productive and reproductive performances, egg quality, antioxidant functions, and intestinal microenvironment in aged breeder laying hens

This study investigated the effects of dietary chlorogenic acid (CGA) on the productive and reproductive performance, egg quality, antioxidant function, and intestinal microenvironment of laying hens. Thus, 162 healthy Hy-Line Brown breeding hens (63 weeks old) were randomly allocated to 3 groups, each receiving a basal diet plus supplementation: 0, 250, and 500 mg/kg CGA, respectively. Per the in vitro test, CGA had obvious inhibitory effects on Salmonella enteritis and avian pathogenic Escherichia coli and strong free radical scavenging ability. Per the breeder laying hen experiment, the CGA diets had no significant influence on egg production or reproductive performance (P < 0.05). Nevertheless, compared with the control diet, 250 mg/kg CGA significantly increased eggshell thickness, egg weight, yolk color, and Haugh unit (P < 0.05). Compared with the control diet and 500 mg/kg CGA, 250 mg/kg CGA significantly (P < 0.05) elevated antioxidant capacity by reducing serum malondialdehyde content, upregulating heme oxygenase-1, and downregulating heat shock proteins mRNA levels in the ileum. Compared with the control diet and 500 mg/kg CGA, 250 mg/kg CGA (P < 0.05) enhanced intestinal barrier function, shown by the upregulation of ileal Occludin and Mucin-2 mRNA levels; furthermore, 250 mg/kg CGA (P < 0.05) increased anti-apoptotic capacity by increasing B-cell leukemia/lymphoma 2 gene expression and downregulated Bcl2 Associated X mRNA levels in the liver and ileum of late breeder laying hens (P < 0.05). Lastly, 250 mg/kg CGA (P < 0.05) increased cecal g_CHKCI001 and short-chain fatty acid-producing bacteria g_Prevotellaceae UCG-001, positively related to gut health, and in the cecum, 500 mg/kg CGA significantly (P < 0.05) increased g_Shuttleworthia abundance, negatively related to gut health. Our findings suggest that dietary inclusion of 250 mg/kg CGA promotes egg quality, intestinal microbial composition, gut barrier integrity, and the antioxidant capacity of aged breeder laying hens.

Histological and molecular difference in albumen quality between post-adolescent hens and aged hens

The decline in albumen quality resulting from aging hens poses a threat to the financial benefits of the egg industry. Exploring the underlying mechanisms from the perspective of cell molecules of albumen formation is significant for the efficient regulation of albumen quality. Two individual groups of Hy-Line Brown layers with ages of 40 (W40) and 100 (W100) wk old were used in the present study. Each group contained over 2,000 birds. This study assessed the egg quality, biochemical indicators and physiological status of hens between W40 and W100. Subsequently, a quantitative proteomic analysis was conducted to identify differences in protein abundance in magnum tissues between W40 and W100. In the W40 group, significant increases (P < 0.05) were notable for albumen quality (thick albumen solid content, albumen height, Haugh unit), serum indices (calcium, estrogen, and progesterone levels), magnum histomorphology (myosin light-chain kinase content, secretory capacity, mucosal fold, goblet cell count and proportion) as well as the total antioxidant capacity of the liver. However, the luminal diameter of the magnum, albumen gel properties and random coil of the albumen were increased (P < 0.05) in the W100 group. The activity of glutathione, superoxidase dismutase, and malondialdehyde in the liver, magnum, and serum did not vary (P > 0.05) among the groups. Proteomic analysis revealed the identification of 118 differentially expressed proteins between the groups, which comprised proteins associated with protein secretion, DNA damage and repair, cell proliferation, growth, antioxidants, and apoptosis. Furthermore, Kyoto Encyclopedia of Genes pathway analysis revealed that BRCA2 and FBN1 were significantly downregulated in Fanconi anemia (FA) and TGF-β signaling pathways in W100, validated through quantitative real-time PCR (qRT-PCR). In conclusion, significant age-related variations in albumen quality, and magnum morphology are regulated by proteins involved in antioxidant capacity.

Influence of Dietary Probiotic and Alpha-Monolaurin on Performance, Egg Quality, Blood Constituents, and Egg Fatty Acids' Profile in Laying Hens

This work was designed to evaluate the advantages of using multi-strain probiotics feed (Bacillus subtilis, Bacillus licheniformis and Clostridium butyricum) (PRO) and alpha-monolaurin (AML) on laying performance, criteria of egg quality, blood parameters, and yolk fatty acids' profile in laying hens. One hundred forty of Bovans brown laying hens at 45 weeks old (25th week of egg production) were randomly allocated into four groups, with seven replicates of five birds each in a complete randomized design. The first group was fed a basal diet without feed additives (0 g/kg diet), and the second, third, and fourth groups received diets containing 1 g PRO, 1 g AML, and 1 g PRO + 1 g AML/kg diet, respectively. No significant impacts of PRO, AML, or their mixture on body weight (BW), body weight gain (BWG), feed intake (FI), or egg weight. Egg production, egg mass, and feed conversion ratio (FCR) were enhanced by 1 g PRO/kg and /or 1 g AML/kg supplementation in laying hen diets. Furthermore, egg shape index, eggshell thickness, and yolk color were statistically higher by PRO and AML supplementation at 55 weeks. However, oviduct, infundibulum, and uterus weights were significantly decreased by 1 g PRO or/and 1 g AML. Additionally, total cholesterol, triglycerides, low density lipoprotein (LDL), glucose, and glutamate pyruvate transaminase (GPT) levels were decreased by PRO and AML supplementation. In conclusion, it seems that dietary inclusion with 1 g PRO/kg, 1 g of AML/kg, and 1 g PRO + 1 g AML improved egg production, egg mass, FCR, and yolk fatty acids profile and lowered total cholesterol and malondialdehyde (MDA) contents in laying hens.

Effect of tamoxifen treatment on catalase (CAT) and superoxide dismutase (SOD) expression and localization in the hen oviduct

The imbalance between free reactive oxygen species (ROS) generation and removal (e.g., by antioxidative enzymes) leads to the damage of important biomolecules and cells. Earlier studies in hens showed that treatment with tamoxifen (TMX; estrogen receptor inhibitor) modulates oxidative stress and causes the reproductive system regression realized by cell apoptosis. The aim of the present study was, therefore, to examine the expression and immunolocalization of the key enzymatic antioxidants, i.e. catalase (CAT) and superoxide dismutase (SOD), in the chicken oviduct following TMX treatment. Laying hens were treated daily with TMX until a pause in egg-laying occurred and then euthanized on day 8 of the experiment. Quantitative real-time PCR and western blot analyses showed the presence of CAT and SOD transcripts and proteins, respectively, in all oviductal segments, i.e., the infundibulum, magnum, isthmus, shell gland and vagina. In control hens (laying), the mRNA expression of CAT was the highest in the shell gland, lower in the isthmus and the lowest in other oviductal parts, whereas protein expression was the highest in the magnum, lower in the isthmus and the lowest in other segments. The SOD transcript and protein abundances only were lower in the magnum than in other segments. Immunoreactive CAT and SOD products were localized in all layers of the oviductal wall, but the intensity of staining depended on the cell type. TMX treatment affected CAT and SOD expression and the effect of TMX depended on gene, protein, cell type and oviductal part. Generally, CAT expression was elevated, while SOD expression was decreased under TMX treatment. These results point to the importance of CAT and SOD in the maintenance of proper oviduct health and function. Changes in ROS scavenging enzymes after estrogen receptor blockage indicate the significance of estrogen in the regulation of oxidative status in the avian oviduct.

Effect of papaya (Carica papaya) seed as phytogenic feed additives on egg performance, egg quality and blood serum biochemical constituents of layer hens

BACKGROUND

Supplementing poultry diets with certain natural phytogenic additives has positive impacts on performance parameters like feed intake, egg production and quality of layer hens.

OBJECTIVES

The study aimed to examine how supplementing papaya seed as phytogenic feed additive (PFA) to the diets of layer chickens affected their egg production, quality and blood serum biochemical parameters.

METHODS

One hundred twenty 28-week-old Bovans brown laying hens were randomly assigned to one of four treatments with varying levels of papaya seed supplementation at 0 g/kg (T1), 5 g/kg (T2), 10 g/kg (T3) and 15 g/kg (T4) in a complete randomized design.

RESULT

Layer chickens supplemented with 0.5% (T2), 1% (T3) and 1.5% (T4) papaya seed as a PFA had significantly (p < 0.05) improved dry matter intake, egg production%, egg mass and feed conversion. On the other hand, papaya seed supplementation decreased (p < 0.05) the bodyweight gain of laying hens. Papaya seed supplementation significantly (p < 0.05) increased egg weight, length, width, yolk height and yolk colour compared to the control group. Serum total protein on T4 and liver enzyme of alkaline phosphatase on T3 were significantly greater (p < 0.05) than in the control group. However, there were no significant differences (p > 0.05) in serum albumin, glucose, total cholesterol, triglyceride and aspartate aminotransferase levels among treatments laying hens.

CONCLUSION

Papaya seed can be a potential candidate as a PFA at 5-15 g/kg of the basal diet to improve egg-laying performance and quality without deteriorating effect.

Effects of garcinol supplementation on the performance, egg quality, and intestinal health of laying hens in the late laying period

The problem of rapid decline in egg production performance and poor egg quality is a key obstacle to improving the economic benefits of laying hens. Garcinol is an antioxidant polyphenol plant extract that has multiple physiological functions. Diets with the appropriate amount of garcinol might be able to improve the performance traits and health of late laying hens. Therefore, this study was conducted to evaluate the utilization of garcinol in late laying hens. A total of 400 healthy 59-wk-old Tingfen No. 6 hens were randomly allocated into 4 dietary treatment groups and fed a basal diet supplemented with 0, 100, 300, and 500 mg/kg garcinol for 12 wk, denoted the Con, LG, MG, and HG groups, respectively. The results showed that the addition of garcinol in the diet tended to increase the egg production rate compared with that of the control group (P = 0.080), while the average egg weight was significantly lower (P < 0.05) during the whole period of the experiment. The results showed that MG group hens had higher egg quality and strengthened antioxidant capacity in their serum (P < 0.05). Moreover, the laying hens in the MG group had significantly decreased crypt depth (CD) and increased villus height (VH) in the jejunum and ileum (P < 0.05), as well as an increased ratio of VH to CD (P < 0.05) and increased expression levels of Occludin (P < 0.05) and Claudin-2 (P < 0.05) in the jejunum to improve intestinal barrier function. In addition, dietary supplementation with garcinol influenced the cecal microbiota of laying hens, which was characterized by changes in the microbial community composition, including increased abundances of Firmicutes, Romboutsia, and Ruminococcus torques. In conclusion, dietary 300 mg/kg garcinol supplementation could increase the egg production and egg quality of late laying hens, which may be attributed to the antioxidant effects of garcinol and the improvement of intestinal morphology and epithelial barrier function as well as the regulation of mucosal immune status by altering microbial composition.

Supplemental dietary genistein improves the laying performance and antioxidant capacity of Hy-Line brown hens during the late laying period

The present study evaluated the effects of 3 supplemental levels of dietary genistein ingested during the late laying period (66-73 wk) of laying hens. A total of 384 Hy-Line brown hens (66 wk old) were randomly divided into 4 groups (6 replicates of 16 hens in each group), the basal diet group (CON), and groups for the basal diet supplemented with 80, 120, and 400 mg/kg of genistein, G1, G2, and G3, respectively. The results of the present study showed an increased laying rate in groups G2 and G3 (linear, P < 0.01), and decreased feed-egg ratios (linear, P < 0.05) and broken egg rate (P < 0.01) in all genistein-treated groups compared with the CON group. Moreover, the G2 group showed an increase in eggshell strength and ratio (linear, P < 0.05), whereas all genistein-treated groups saw a decrease in the L* value (linear, P < 0.01) and an increase in the a* value (linear, P < 0.05) compared with the CON group. Additionally, all genistein-treated groups had an increase in the total antioxidant capacity of plasma (linear, P < 0.05), along with reduced plasma, ovarian, and yolk malondialdehyde levels (linear, P < 0.05), compared with the CON group. The G2 group had an increase in both the superoxide dismutase activity of plasma (P < 0.01) and the total antioxidant capacity of the ovaries (linear, P < 0.05), compared with the CON group. The G3 group had an increase in both the glutathione peroxidase concentration of plasma (linear, P < 0.05) and the total antioxidant capacity of the ovaries (linear, P < 0.01), compared with the CON group. The transcript levels of nuclear factor erythroid 2-related factor 2, superoxide dismutase 1, and catalase were increased in all of the genistein-treated groups (P < 0.05) compared with the CON group, whereas heme oxygenase 1 and glutamate-cysteine ligase modifier subunit were increased only in the G2 group (P < 0.05). In conclusion, supplementation with 120 mg/kg dietary genistein had the best effect on improving the laying rate, eggshell quality, and antioxidant capacity in Hy-Line brown hens during the late laying period.

Interaction between the flagellum of Candidatus Liberibacter asiaticus and the vitellogenin-like protein of Diaphorina citri significantly influences CLas titer

Huanglongbing (HLB) is a global devastating citrus disease that is mainly caused by "Candidatus Liberibacter asiaticus" (CLas). It is mostly transmitted by the insect Asian citrus psyllid (ACP, Diaphorina citri) in a persistent and proliferative manner. CLas traverses multiple barriers to complete an infection cycle and is likely involved in multiple interactions with D. citri. However, the protein-protein interactions between CLas and D. citri are largely unknown. Here, we report on a vitellogenin-like protein (Vg_VWD) in D. citri that interacts with a CLas flagellum (flaA) protein. We found that Vg_VWD was upregulated in CLas-infected D. citri. Silencing of Vg_VWD in D. citri via RNAi silencing significantly increased the CLas titer, suggesting that Vg_VWD plays an important role in the CLas-D. citri interaction. Agrobacterium-mediated transient expression assays indicated that Vg_VWD inhibits BAX- and INF1-triggered necrosis and suppresses the callose deposition induced by flaA in Nicotiana benthamiana. These findings provide new insights into the molecular interaction between CLas and D. citri.

Effects of Pennyroyal (Mentha pulegium L.) Supplementation on production performance, egg quality traits, and biochemical parameters of blood and egg in laying hens at later stages of the production period

BACKGROUND

According to the promising outcomes acquired in recent studies that focused on using natural feed additives in animal nutrition, poultry nutritionists have also been interested in investigating these medicinal herbs' effects on poultry performance and egg characteristics. Pennyroyal (Mentha pulegium L.), a natural source of antioxidant, antimicrobial, anti-inflammatory, etc. compounds, is recommended as a potential alternative for antibiotics, with similar benefits and no adverse effects on animal health or their products. Considerable effects have been reported on laying hens' performance and their eggs' internal and external traits by pennyroyal inclusion in their diets.

OBJECTIVES

Due to the different results reported by pennyroyal inclusion in laying hens' diets in recent limited studies, this study was designed to reinvestigate the impacts of pennyroyal (Mentha pulegium L.) supplementation (PS) on productive performance, egg quality traits, and biochemical compounds in blood and egg yolk in aged laying hens. The findings of this experiment may help for a better understanding of PS impacts on desired parameters, along with improving aged laying hens' performance.

MATERIALS AND METHODS

A total of 144 Leghorn (Hyline-W36 strain) laying hens (53 weeks old) were used to investigate the effects of PS on performance, egg quality, and biochemical parameters of blood and egg yolk in old laying hens. The animals were distributed into three treatment groups; including a control diet (without PS), 0.5%, and 1% PS diets with six replicates and eight birds per replicate.

RESULTS

The results indicated that the egg production rate (except for week eight) and egg mass were significantly reduced by PS in the laying hens' diet during the first four weeks and the total period of the experiment (P<0.05). However, the feed conversion ratio increased by PS (P<0.05). Based on the egg quality trait evaluations (week 4), the yolk percentage, yolk height, and yolk index reduced, while shell-breaking strength represented a significant increase in PS groups (P<0.05). However, shell thickness and albumen percentage reduced and increased by 1% PS, respectively (P<0.05). At week eight, the Haugh unit reduced while the albumen pH increased by PS (P<0.05). The findings revealed a decline in the egg density in 1% PS groups (P<0.05). In the case of serum biochemical parameters, alanine aminotransferase increased, whereas malondialdehyde (MDA) levels reduced in the PS groups (P<0.05). Moreover, the triglyceride levels of both serum and egg yolk (accompanied by the very low-density lipoprotein level of serum) decreased by PS (P<0.05).

CONCLUSIONS

In conclusion, PS reduced serum and egg yolk triglyceride levels, accompanied by serum MDA, along with reducing production performance.

Insulin-like growth factor-1 is involved in the deteriorated performance of aged laying hens

The underlying mechanism behind the deteriorated laying performance of aged laying hens remains unclear. In the present study, the laying performance and gene expression along the hypothalamus-pituitary-gonad axis were determined. A total of 300 healthy 90-wk-old ISA hens with similar body weights were classified into three groups according to their laying rate between 90 and 94 wk of age. The experimental groups were the low laying rate (<60%, LLR), high laying rate (>85%, HLR), and intermediate laying rate (60% < laying rate < 85%, MLR) hens. At the end of 94 wk of age, eight hens were randomly selected from each group for tissue collection. The gene expression of hormones and their receptors were determined in the hypothalamus, pituitary, and follicles. The results showed that the serum 17-β-estradiol had no significant difference among the three groups. However, the level of insulin-like growth factor 1 (IGF1) in LLR hens was significantly decreased in the serum, small white follicles (SWF), and dominant follicles (DF, P < 0.05). Within the hypothalamus and small yellow follicles (SYF), the mRNA expression level of estrogen receptor was higher in the MLR group (P < 0.05). Compared with HLR hens, the steroid hormone-synthesis key gene, CYP19A1 was significantly decreased in the SWF of MLR-hens and DF of MLR- and LLR-hens (P < 0.05). The mRNA expression level of IGF1 receptor was higher in the hypothalamus, pituitary, SWF, large white follicles (LWF), SYF, and DF of LLR hens, compared to the HLR hens (P < 0.05). These results suggest that decreased IGF1 in serum and follicles was associated with the decreased egg production of aged laying hens. The present study provides novel insights into the endocrine changes in aged hens having different egg production.

Lipoamide Alleviates Oxidized Fish Oil-Induced Host Inflammatory Response and Oxidative Damage in the Oviduct of Laying Hens

Fish oil (FO) is an important source of lipid in functional food and aquafeeds. However, the harmful effects of oxidized fish oil (OFO) on host metabolism and reproductive health are not yet clear. In addition, lipoamide (LAM) has been widely studied as an agent for alleviating various diseases associated with oxidative disruption. Therefore, in the current study, to investigate the effects of LAM in alleviating OFO-induced decline in reproductive performance and oxidative damage to the oviduct in laying hens. We constructed a 1% fresh FO model, a 1% OFO model, and a LAM model with 1% OFO (OFO + LAM) added at 100 mg/kg to explore the antioxidant effect of LAM. Herein, these results were evaluated by breeding performance, immune responses, estrogen, and antioxidant indices of serum samples, as well as the number of follicles and antioxidant parameters of oviducts. From the results, compared with the FO group, OFO significantly decreased the egg-laying rate, increased the contents of total protein (TP) and inflammatory factors [tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-8, and interferon γ (INF-γ)], and reduced the concentrations of anti-oxidation [total antioxidant (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), glutathione (GSH), glutathione reductase (GR), catalase (CAT), and hydroxyl radical scavenging activity (HRSA)] in serum samples, as well as reduced the levels of anti-oxidation indexes in oviduct tissues (p < 0.05). Of note, the supplementation of LAM could significantly increase the laying performance, improve the levels of serum immunoglobulins (IgA, IgG, and IgM), serum estrogen [progesterone (P) and estradiol (E2)], and serum antioxidant parameters (T-AOC, T-SOD, GSH-Px, GSH, GR, CAT, and HRSA) and decrease the concentrations of serum inflammatory cytokines (TNF-α, IL-6, IL-8, and INF-γ) in laying hens following OFO administration (p < 0.05). In addition, LAM could dramatically increase the contents of antioxidant factors (p < 0.05) in oviducts and enhance the secretion capacity of the uterine part. Taken together, OFO caused host metabolic dysfunction, oxidative damage, uterine morphological abnormalities, and alterations of ovarian function. These results suggested that LAM administration could alleviate host metabolic dysfunctions and inflammatory damage, and then ameliorate oxidative damage in the oviduct induced by OFO, ultimately improving reproductive function.

Effects of yeast hydrolysate on growth performance, serum parameters, carcass traits, meat quality and antioxidant status of broiler chickens

BACKGROUND

Yeast hydrolysate (YH) has multiple salutary biological activities. Nevertheless, the application of YH in broiler production is limited. This study was conducted to evaluate the protective effects of YH derived from Saccharomyces cerevisiae by exploring growth performance, serum parameters, organs relative weight, carcass traits, meat quality and antioxidant status of broilers.

RESULTS

Supplementing YH linearly and quadratically improved (P < 0.05) body weight gain and gain-to-feed ratio compared to that in the control group. Triglycerides, low-density lipoprotein cholesterol and total cholesterol in serum, the decline in pH and cooking loss of breast muscle, and malonaldehyde concentration in serum and liver were decreased linearly and/or quadratically by YH (P < 0.05), whereas high-density lipoprotein cholesterol in serum, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in serum, GSH-Px activity in liver, glutathione content in serum and liver, eviscerated yield rate and chest muscle yield, and the relative weight of spleen and liver were linearly and/or quadratically increased (P < 0.05). Moreover, YH enhanced the mRNA levels of nuclear factor erythroid 2-related factor 2, heme oxygennase-1 (HO-1), GSH-Px1 and SOD1 (linear and/or quadratic, P < 0.05).

CONCLUSION

Dietary YH beneficially affected growth performance, serum parameters, organ relative weight, carcass traits, meat quality and antioxidant status in broilers, indicating its potential application as a promising feed additive in broiler production. © 2021 Society of Chemical Industry.

Dietary mulberry-leaf flavonoids improve the eggshell quality of aged breeder hens

Eggshell quality is subject to a significant decline in the late laying period, which results in huge economic losses. The purpose of this study was to investigate the effects of dietary mulberry-leaf flavonoids (MF) on the eggshell quality of aged breeder hens. A total of 270 (60-week-old) Qiling breeder hens were randomly assigned to 3 treatments with supplemental dietary MF doses (0, 30, and 60 mg/kg). The results showed that dietary MF improved the eggshell thickness and strength, following the reduced broken egg ratio (P < 0.05). Histological analysis showed that dietary MF increased glandular density and luminal epithelium height in the shell gland (P < 0.05). MF treatment reduced the apoptotic index of the shell gland, following by improved antioxidant capacity (P < 0.05). The protein expression of Caspase 3 was down-regulated, and Nrf2 was up-regulated by dietary MF (P < 0.05). Furthermore, calcium (Ca) content in the serum and shell gland, as well as the activity of Ca²⁺-ATPase in the shell gland were increased by dietary MF (P < 0.05). Ca transport-related genes (ESRα, ESRβ, KCNA1, OPN, CABP-28K and CDH6) in the shell gland were upregulated by dietary MF treatment (P < 0.05). In conclusion, dietary MF could ameliorate the eggshell quality of aged hens by improving antioxidative capability and Ca deposition in the shell gland of uterus.

Productive Performance, Ovarian Follicular Development, Lipid Peroxidation, Antioxidative Status, and Egg Quality in Laying Hens Fed Diets Supplemented with Salvia officinalis and Origanum majorana Powder Levels

This study aimed to assess the effect of dietary supplementation with different levels of Salvia officinalis and/or Origanum majorana on productive performance, ovarian follicular development, lipid peroxidation, antioxidative status, and egg quality in laying hens. Two hundred and ninety-four 45-week-old Bovans brown hens were allocated into seven groups, with seven replicates of six hens each. The first group was fed with the basal considered as a control (A); the second (B) and third (C) groups were provided with the same control diet further supplemented with 0.5 and 1 kg/ton Salvia officinalis, respectively; the fourth (D) and fifth (E) groups received the control diet further supplemented with 0.5 and 1 kg/ton Origanum majorana, respectively; while the sixth (F) and the seventh (G) groups were offered a diet supplemented with 0.5 kg/ton Salvia officinalis and 0.5 kg/ton Origanum majorana and 1 kg/ton Salvia officinalis and 1 kg/ton Origanum majorana, respectively. No significant effects were observed in the final body weight (BW) and feed intake (FI) of the laying hens. In the diets supplemented with Salvia officinalis and Origanum majorana, the egg weights for groups C, F, and G had significantly higher values only compared to group D. The supplementation of the diets with Salvia officinalis and/or Origanum majorana significantly (p < 0.05) increased the Follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol estrogenic hormone concentration, except for Origanum majorana at both levels with regard to estradiol. The dietary utilization of Salvia officinalis and Origanum majorana did not significantly alter the plasma glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT), total protein, albumin, globulin, and High density lipoprotein (HDL) parameters. Cholesterol, glucose, triglyceride, and Low density lipoprotein (LDL) were decreased (p < 0.05) in the birds fed with Salvia officinalis and/or Origanum majorana supplemented diets. Moreover, at both doses, the dietary supplementation with Salvia officinalis and Origanum majorana decreased (p < 0.05) the yolk cholesterol and liver Malondialdehyde (MDA) levels. In addition, the dietary enrichment with Salvia officinalis and/or Origanum majorana decreased (p < 0.05) the palmitoleic and stearic fatty acids' egg yolk concentration. In contrast, the yolk linoleic fatty acid concentration was significantly increased by Salvia officinalis and/or Origanum majorana. In conclusion, dietary supplementation with Salvia officinalis and/or Origanum positively affected productive performance, ovarian follicular development, antioxidant activity, hormonal status, and steroidogenesis in Bovans brown laying hens.

Dietary mulberry-leaf flavonoids supplementation improves liver lipid metabolism and ovarian function of aged breeder hens

Mulberry-leaf flavonoids (MF), extracted from mulberry leaves, exert antioxidant and hypolipidemic effects. The purpose of this experimental study was to investigate the effects of dietary MF on the ovarian function and liver lipid metabolism of aged breeder hens. We used 270 (60-weeks-old) Qiling breeder hens randomly assigned in 3 treatments with supplemental dietary MF doses (0, 30, 60 mg/kg). The results showed that dietary MF significantly improved the egg-laying rate, followed by the reduced feed conversion rate (FCR) (p < 0.05). However, there is no obvious difference in hatchability and fertilised eggs hatchability among the three groups (p > 0.05). The level of T-CHO, LDL-C and AKP in serum was reduced, and the HDL-C concentrations were increased by dietary MF (p < 0.05). MF treatment also improved the antioxidant capacity and reduced the apoptotic index of the ovary (p < 0.05). Additionally, dietary MF significantly increased the serum estradiol (E2) levels (p < 0.05) and the transcription level of CYP19A1 and LHR in the ovary (p < 0.05). Dietary MF enhanced fatty acid β-oxidation in the liver via up-regulating the mRNA expressions of PPARα and CPT-I (p < 0.05). Moreover, the HMF group significantly decreased mRNA expressions of SREBP-1c (p < 0.05) and increased mRNA expressions of ERα, VTG-Ⅱ and ApoB in the liver (p < 0.05). In conclusion, dietary MF could improve the reproduction performance of aged breeder hens through improving ovary function and hepatic lipid metabolism.

Dietary hawthorn-leaves flavonoids improves ovarian function and liver lipid metabolism in aged breeder hens

Hawthorn-leaves flavonoids (HF), extracted from hawthorn leaves, were reported to exert antioxidant, anti-inflammatory and hypolipidemic properties. The aim of our study was to investigate the effects of dietary HF on the reproduction performance and liver lipid metabolism of aged breeder hens. A total of 270 aged Qiling breeder hens (60-wk-old) were randomly divided into 3 treatments: 1) basic corn-soybean diet (CON); 2) basic corn-soybean diet supplemented with 30 mg/kg HF (LHF); 3) basic corn-soybean diet supplemented with 60 mg/kg HF (HHF). The results showed that supplemented HF significantly improved the egg-laying rate and hatching rate of aged breeder hens (P < 0.05). HF treatment reduced the serum TG, T-CHO and L-LDL levels (P < 0.05), and upregulated the mRNA expressions of ESR1, ESR2, VTGⅡ, ApoB, and ApoVI in the liver (P < 0.05). Serum estrogen levels in HF treated groups were elevated compared with the CON group (P < 0.05). In the HHF group, the number of the primordial follicles was higher in comparison with the CON group (P < 0.05). Furthermore, dietary supplementation with HF improved the activity of antioxidant enzymes (T-AOC, GSH-Pχ) (P < 0.05), following with the reversed ovarian apoptosis and morphological damage. In addition, 60 mg/kg dietary HF upregulated the protein expression of PCNA and Nrf2 in the ovary (P < 0.05). In summary, dietary supplementation with HF could improve the reproduction performance through regulating liver lipid metabolism and improving ovarian function in aged breeder hens.

Effect of dietary supplementation with nettle or fenugreek on folliculogenesis and steroidogenesis in the rabbit ovary - An in vivo study

The objective of the study was to investigate the effect of dietary supplementation with nettle or fenugreek on folliculogenesis and steroidogenesis in the juvenile rabbit ovary. To gain insight into the mechanism of action of these herbs, we examined follicle formation, ovarian cell proliferation and apoptosis, steroidogenic enzyme abundance and steroid concentrations in ovarian tissue and plasma. Animals were fed with control, 1% nettle- or 1% fenugreek-supplemented pellets from 5 to 12 weeks of age (n = 10 per each group), when animals were slaughtered for ovary and blood collection. The addition of nettle decreased the numbers of primordial (P = 0.015) and early antral (P = 0.02) follicles and increased the number of primary (P = 0.04) ones when compared with the control group. Following fenugreek supplementation, the numbers of primary (P = 0.008) and antral (P = 0.027) follicles were greater, while the number of early antral (P = 0.003) follicles was lower in comparison with the control group. Nettle revealed apoptotic activity through activation of caspases 9 (P = 0.047), 8 (P = 0.022) and 3 (P = 0.004), whereas fenugreek increased (P = 0.042) follicular cell proliferation marked by PCNA protein abundance. Furthermore, only fenugreek targeted steroidogenic enzymes, decreasing CYP17A1 (P = 0.043) and increasing CYP19A1 (P = 0.048) protein abundances that resulted in enhanced estradiol biosynthesis and its elevated (P = 0.006) plasma concentration. In conclusion, both herbs affected follicle development in the rabbit ovary in a stage specific manner. Additionally, fenugreek altered ovarian steroidogenesis in a way that might affect sexual maturation in rabbits.

Use of extruded eggshell as a calcium source substituting limestone or oyster shell in the diet of laying hens

The nutritional values of limestone, oyster shell and extruded eggshells were evaluated using different methods. In total, 120 ready‐to‐lay pullets, 18‐week‐old ISA Brown were distributed into six dietary groups, namely D₁ (4% limestone), D₂ (8% limestone), D₃ (4% oyster shell), D₄ (8% oyster shell), D₅ (4% eggshell) and D₆ (8% eggshell), to assess the effect of calcium sources on egg production, egg quality, dry matter and cholesterol content of the egg. Kitchen‐extruded eggshell contained 98.52, 4.24, 29.75 and 14.82% DM, CP, Ca and P, whereas hatchery‐extruded eggshell contained 99.20, 13.80, 25.53 and 13.87% DM, CP, Ca and P, respectively. Limestone and Oyster shells contained 99.60 and 99.51% DM, and 37.12 and 35.20% Ca, respectively. Body weight, egg, hen day and egg mass production, and FCR did not differ among diets (p > .05). Egg production tended to increase with the increase of hen‐housed egg production (p < .001) in D₆, followed by D₂, D₅, D₃, D₄ and D₁, respectively. The lowest production cost and the highest net profit were observed in D₆, followed by D₂, D₄, D₅, D₁ and D₃, respectively. Diet with 8% Ca sources performed better than the diets with 4% Ca sources in terms of egg quality and dry matter content, where D₆ was comparable to D₂ or D₄. The weight of egg, albumen, yolk, eggshell, dry yolk and yolk–albumen ratio increased, while dry albumen and eggshell weight, eggshell strength and thickness, Haugh unit, yolk index and egg‐specific gravity decreased with the increase in bird's age. The cholesterol content of yolk was statistically similar among diets. Therefore, no adverse effect of calcium sources on the production of laying hen was observed. Of these, extruded eggshell especially the 8% extruded eggshell may be beneficial to use in the diet of laying hen for producing a quality, safe and profitable egg.

Effect of Dietary Inclusion of Alpha-Monolaurin on the Growth Performance, Lipid Peroxidation, and Immunity Response in Broilers

As the world population increases, there will be an increase in demand for poultry meat. To satisfy this requirement, sustainably will be a significant challenge as different countries in the world face different health problems. Additionally, for decades, poultry nutritionists have worked on sustainability in broiler manufacturing plants. The usage of short- and medium-chain fatty acids (MCFAs), which have positive effects as growth promoters and immunostimulants, is a pioneering way to decrease the cost of diets and improve environmentally friendly and sustainable production in this critical era. This study aimed at evaluating the influences of alpha-monoglyceride (alpha-monolaurin) on the growth performance, biochemical parameters, lipid profiles, liver oxidative stress, and immune response in broilers. Alpha-monolaurin was included at the levels of 0 (control), 0.25, 0.5, and 1 g/kg in broiler diets. After 33 days, dietary supplementation of alpha-monolaurin showed no impact on the feed intake; however, broilers fed 0.5 g/kg feed displayed a significantly reduced food conversion ratio, as compared to the control (p ≤ 0.05). However, body weight and body weight gain tended to increase after 0.25 g/kg alpha-monolaurin supplementation, as compared to other groups. The highest European production efficiency factor (EPEF) was obtained with 0.25 g/kg alpha-monolaurin supplementation. The ether extract utilization and spleen weight were improved substantially (p ≤ 0.05) by alpha-monolaurin supplementation, but muscle and other organ weights were not affected. Plasma alanine transaminase (ALT) was decreased significantly by alpha-monolaurin supplementation, while plasma total protein and albumin were enhanced (p ≤ 0.05). Interestingly, broilers fed alpha-monolaurin displayed an increased antibody titer of the Newcastle disease (ND) virus and muscle unsaturated fatty acid content, and a decreased liver content of malondialdehyde (MDA). It could be assumed that dietary supplementation of alpha-monolaurin positively impacts birds’ feed efficiency and immune response and can be applied as a natural immune enhancer in the broiler industry.

Evaluation of dried papaya pomace meal in laying hen diets

In the search for alternative feed resources for laying hens, papaya pomace is available as industrial by-product but information on its nutritive value is lacking. Dried papaya pomace was included in a common laying hen diet at 0%, 2.5%, 5% and 7.5% to evaluate its effect on egg production performance, egg quality and general health parameters in Bovan brown layers. For every inclusion level, three cages with ten 20-week-old layers were used, making a total of 120 hens. The effect of dried papaya pomace inclusion on egg production, egg quality and general health parameters was evaluated. Dried papaya pomace inclusion improved egg production and laying by 6.15% and 17% respectively, while it significantly decreased feed conversion ratio by 7.5%. Eggshell weight, thickness and strength of PP5 were higher than the control by 0.3 g, 0.8 mm and 0.43 kg/cm² , respectively. There was a significant improvement in albumin weight (by 1.5 g/L), albumin height (2.1 mm), yolk weight (0.4 g/L), yolk height (0.4 mm), yolk colour (4.4 points) and Haugh unit (8 points) due to PP5 treatment. Inclusion of papaya pomace at a level of 7.5% of layers diet had negative effect on Egg production, feed conversion ratio and interior and exterior egg quality traits. Inclusion of papaya pomace affected significantly serum total cholesterol, serum triglyceride, serum low density lipoprotein, serum high density lipoprotein, aspartate aminotransferase, alanine aminotransferase and white blood cell count. However, all blood traits of the experimental animals were within the normal ranges reported for layers. Inclusion of papaya pomace in 5% of layers commercial diets improves egg production and quality without negative impact on health while decreasing feeding cost.

Effect of Natural and Chemical Colorant Supplementation on Performance, Egg-Quality Characteristics, Yolk Fatty-Acid Profile, and Blood Constituents in Laying Hens

Natural and chemical colorants are attracting a lot of attention as sustainable feed additives due to their effect on food color and because presentation matters to consumers. Color also is a major sensory factor that helps consumers determine food quality and its possible health benefits. For example, highly colored egg yolks can only come from healthy laying hens fed a well-balanced, nutrient-rich diet. Consumers associate an intense yolk color with healthy, nutrient-rich food. There is a growing market request for eggs with rich yolk coloring. The purpose of the current study was to evaluate the impact of natural (paprika) and chemical (carmoisine) colorant supplementation on the performance, egg-quality characteristics, yolk fatty-acid profile, and blood constituents in laying hens. A total of 240 Bovans laying hens were randomly distributed in a completely randomized design in four treatments according to four experimental diets: a control diet (without supplementation of any colorants), a control diet supplemented with 4 kg/ton paprika, a control diet supplemented with 150 g carmoisine/ton, and a control diet supplemented with a combination of 4 kg/ton paprika plus 150 g carmoisine/ton, fed from 42 to 54 weeks of age. Each treatment consisted of 10 replications with six hens. Dietary inclusion of paprika colorant improved (p < 0.05) the feed-conversion ratio and egg-production rate, while final body weight, weight change, feed intake, and egg weight and mass were not affected. The degrees of egg yolk and white were increased (p < 0.05) by the dietary supplements. Yolk color and shell thickness were enhanced (p < 0.05) by adding paprika and/or carmoisine colorants. Supplementation of the paprika colorant alone or in combination with carmoisine increased (p < 0.05) linolenic acid, oleic acid, and vitamin E concentrations in egg yolks. In contrast, egg yolk palmitic acid and liver malondialdehyde contents were decreased (p < 0.05). Paprika and carmoisine colorants and their combination improved (p < 0.05) blood lipid profile in treated hens. We concluded that the dietary supplementation of natural (paprika) colorants has an influential role in improving egg yolk color, production performance, and egg yolk fatty-acid profile in laying hens.

Dusk feeding in laying hens is shifted by light program via involvement of clock genes

Dusk feeding is practised probably to satisfy the energy requirement during night. However, little is known on the changes with clock gene expressions during this feeding behaviour. In our present study, the linkage of clock gene expressions and feeding behaviour in dusk feeding was investigated in laying hens under two lighting programs: the conventional lighting program (Control) with a light period from 05:00 AM to 21:00 PM and a dark period from 21:00 PM to 05:00 AM; or the shifted lighting program group (SLP) with a light period from 02:00 AM to 18:00 PM and a dark period from 18:00 PM to 02:00 AM. The gene expression-related appetite and circadian rhythm were investigated in hypothalamus and proventriculus at 1, 3 and 5 h before scotophase. The results demonstrated that dusk feeding was synchronously shifted with altered lighting program, dusk feeding was observed from 5 h before scotophase in both groups. The expressions of anorexigenic gene proopiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART) were downregulated (p < 0.05) during dusk feeding and changed in pace with lighting program. The expressions of clock gene period 2 (Per2) and cryptochrome 1 (Cry1) in hypothalamus were downregulated (p < 0.05) during dusk feeding and shifted by lighting program. In the proventriculus, ghrelin expression was decreased (p < 0.05) during dusk feeding by lighting program. In conclusion, the expressions of clock genes Per2 and Cry1 are linked with the downregulated expressions of anorexigenic genes, POMC and CART, and in turn the augmented feed intake at dusk.

Effects of Sunflower Meal Supplementation as a Complementary Protein Source in the Laying Hen’s Diet on Productive Performance, Egg Quality, and Nutrient Digestibility

The practical usage of untraditional feedstuffs such as sunflower meal (SFM) in laying hens nutrition in developing countries has received considerable attention. SFM is a by-product of the sunflower oil industry and has been progressively added to bird’s diets. Sunflower meal (SFM) is gaining great interest as a feed ingredient due to its eminent crude protein content, low anti-nutritional compounds, and low price. The current experiment was aimed to assess the production efficiency, egg quality, yolk fatty acids composition, and nutrient digestibility of laying hens fed SFM. A total of 162 Bovans Brown laying hens aged 60 weeks old were randomly allocated using a completely randomized design into three experimental groups of nine replicates each (n = six/replicate) for eight weeks. The dietary treatments involved a control (basal diet) and two levels of SFM, 50 and 100 g/kg feed. The dietary treatments did not influence live weight gain, feed intake, and egg mass. On one hand, the laying rate was increased; on the other hand, the feed conversion ratio and broken eggs rate of laying hens were decreased (p < 0.05) by the dietary inclusion of SFM. Dietary treatments had no effect on the egg’s quality characteristics except the yolk color and yolk height were larger (p = 0.01) for laying hens fed SFM compared with those fed the control. Dietary inclusion of SFM decreased (p < 0.05) the content of cholesterol in the egg yolk. Still, it increased the yolk contents of vitamin E, calcium, linoleic acid, linolenic acid, and oleic acid (p < 0.05). Furthermore, the dietary inclusion of SFM increased crude protein and calcium digestibility, but decreased the ether extract digestibility. In conclusion, our results suggested that the dietary inclusion of SFM, up to 100 g/kg at a late phase of laying, could improve the production performance, some of the egg quality traits, and nutrient digestibility while decreasing egg yolk cholesterol.

Effect of Bacterial or Fungal Phytase Supplementation on the Performance, Egg Quality, Plasma Biochemical Parameters, and Reproductive Morphology of Laying Hens

Simple Summary

The present study shows that 5000 FTU/kg dietary supplementation with bacterial (E. coli) or fungal (Aspergillus niger and Trichodermareesei) sources of phytase with less available phosphorus is capable of maintaining productive efficiency, reproductive morphology, and egg quality of laying hens. Eggshell consistency was increased while yolk cholesterol was decreased as a result of diets supplemented with bacterial or fungal phytase. All in all, our results clarify that feeding laying hens bacterial and fungal phytase at 5000 FTU/kg can be effective to replace inorganic phosphorus commercially.

Abstract

Catalytic and physicochemical properties of microbial phytase sources may differ, affecting phosphorus (P) release and subsequently the productive and reproductive performance of layers. The current study aimed to evaluate the impact of bacterial and fungal phytase sources on layer productivity, egg production, biochemical blood indices, and reproductive morphology. For this purpose, 360 Bovans brown hens at 42 weeks of age were randomly allocated into 4 experimental groups, each with 15 replicates of 6 hens. The first group (control) was fed a basal diet with 4.6 g/kg available P. In contrast, the second, third, and fourth groups were fed diets treated with 3.2 g/kg available P, supplemented with either 5000 FTU/kg of bacterial E. coli (Quantum^TM Blue 5G), fungal Aspergillus niger (VemoZyme^® F 5000 Naturally Thermostable Phytase (NTP)), or fungal Trichodermareesei (Yemzim^® FZ100). Dietary supplementation of bacterial and fungal phytases did not affect the productive performance or egg quality criteria, except for increased shell weight and thickness (p < 0.05). Serum hepatic function biomarkers and lipid profiles were not altered in treated hens, while calcium and P levels were increased (p < 0.05) related to the controls. Ovary index and length, and relative weight of oviduct and its segments were not influenced. The contents of cholesterol and malondialdehyde in the yolks from treated birds were lower compared to control hens, while calcium and P content increased (p < 0.05). Conclusively, bacterial and fungal phytase sources can compensate for the reduction of available P in layers’ diets and enhance shell and yolk quality without affecting productive performance, and no differences among them were noticed.

Effect of feeding wheat middlings and calcium lignosulfonate as pellet binders on pellet quality growth performance and lipid peroxidation in broiler chickens

Basal diets supplemented with 4 kg Ca-LS/ton of diet. Pellet quality characteristics (per cent fines, the present study was conducted to evaluate the influence of wheat middlings (WM) and calcium lignosulfonate (Ca-LS) as pellet binders on the pellet quality characteristics, growth performance, blood parameters, nutrients digestibilities, lipid peroxidation and muscle fatty acids profile in Egyptian broiler strain. A total of 3,120 broiler chicks at 1-day of age were divided randomly into three experimental treatments with eight replicates (130 each). The first treatment was fed the basal pelleted diets without any additives, the second treatment was fed diets including 50 kg WM/ton of diet and the third treatment was fed per cent pellets, and pellet durability index) were significantly improved in WM and Ca-LS treatments compared with the control. Body weight gain was significantly increased, while feed intake was significantly decreased resulting in improving of feed conversion ratio significantly in WM group in comparison with control and Ca-LS groups (p < .05). Nutrients apparent digestibility (dry matter, crude protein and crude fibre) were significantly improved by inclusion of WM compared with control and Ca-LS. Plasma total cholesterol, and uric acid concentrations were significantly decreased by dietary WM in comparison with control and Ca-LS experimental groups. Furthermore, linoleic, alpha-linolenic and arachidonic acids contents in breast muscle were significantly increased by WM and Ca-LS, while, muscle malondialdehyde concentration was significantly decreased. It could be concluded that inclusion of WM and Ca-LS can improve pellet quality characteristics, and WM (at a level of 50 kg/ton) had positive effects on growth performance, nutrients digestibilities, lipid peroxidation and fatty acids profile in Egyptian broiler strain.

Effects of magnolol on egg production, egg quality, antioxidant capacity, and intestinal health of laying hens in the late phase of the laying cycle

Magnolol is a multifunctional plant polyphenol. To evaluate the effects of magnolol on laying hens in the late laying period, 360 (50-week-old) laying hens were randomly assigned to 4 dietary treatments: a non-supplemented control diet (C), and control diets supplemented with 100, 200, and 300 mg/kg of magnolol (M100, M200, and M300), respectively. Each treatment had 6 replicates with 15 hens per replicate. Results showed that dietary supplementation of 200 and 300 mg/kg of magnolol increased the laying rate and the M200 group had a lower feed conversion ratio (P < 0.05). Magnolol supplementation (200 and 300 mg/kg) could linearly increase albumen height and Haugh unit of fresh eggs in the late phase of the laying cycle (P < 0.01). And magnolol linearly alleviated the decline of the albumen height and Haugh unit of eggs stored for 14 d (P < 0.01). The total superoxide dismutase activity in the ovaries of M100 group was greater than that in the other treatments (P < 0.05). As dietary magnolol levels increased, villus height of jejunum and ileum linearly increased (P < 0.01). M200 and M300 groups had higher expression level of occludin in the ileum compared with group C (P < 0.01). The level of nitric oxide production and inducible nitric oxide synthase expression in the ileum of M200 group were lower than that in the C group (P < 0.05). In conclusion, dietary supplementation of 200 and 300 mg/kg magnolol can improve hen performance, albumen quality of fresh and storage eggs, and hepatic lipid metabolism in the late laying cycle. Also, magnolol has a good effect on increasing villi and improving the intestinal mucosal mechanical barrier function.

Alpha-lipoic acid improves the reproduction performance of breeder hens during the late egg-laying period

Alpha-lipoic acid (ALA), a multifunctional antioxidant, can promote fatty acid mobilization, energy expenditure and scavenge free radicals. The effects of dietary ALA on the reproductive performance of breeder hens were investigated in the current study. In the 5-week experiment, 180 54-week-old Qiling breeder hens were randomly divided into three treatments with five replicates and supplemented with three levels of ALA (0, 300 and 600 mg/kg) in the basic corn-soya bean meal diets. 600 mg/kg ALA treatment group (HLA) significantly improved the eggshell thickness and strength (p < .05). ALA-treated groups improved egg-laying rate compared with the CON group, but with no statistically significant difference (p > .05). The levels of HDL-C, ALB and estradiol (E2) of the serum in the HLA group were elevated compared with the CON group (p < .05). In addition, ALA (600 mg/kg) treatment exhibited a reduced level of serum AST and TG (p < .05). Dietary ALA increased the activity of hepatic lipase in liver (p < .05). Supplemental 600 mg/kg ALA also improved the SOD activity and total antioxidant capacity level, along with a decreased MDA in ovarian tissue (p < .05). Furthermore, the mRNA expressions of ESR1, ESR2, VTG2 and ApoB in the liver and FSHR in follicles were upregulated in the HLA group (p < .05). In conclusion, dietary supplementation with 600 mg/kg ALA during the late egg-laying period could improve lipid metabolism and reproductive performance of breeder hens.

Effects of supplementing hen diet with Lavandula angustifolia and/or Mentha spicata essential oils on production performance, egg quality and blood variables of laying hens

Background

Organic products of animals are getting more accepted by consumers. Using herbal additives may lead to more health animal products. In this research it is hypothesized that Lavandula angustifolia and/or Mentha spicata essential oils would be helpful to enhance production performance in laying hens.

Objectives

This experiment was conducted to evaluate the effects of Lavandula angustifolia and Mentha spicata essential oils on performance, egg traits and blood variables in laying hens.

Methods

144 Lohmann LSL‐Lite laying hens from 42 until 56 weeks of age were used in a completely randomized design in four treatments and six replicates (six birds per replicate). The treatments consisted of: (a) control group (basal diet), (b) basal diet supplemented with 250 mg/kg diet lavender essential oil (LEO), (c) basal diet supplemented with 250 mg/kg diet mint essential oil (MEO), and (d) basal diet supplemented with both LEO and MEO.

Results

Using LEO and/or MEO did not affect body weight changes, feed intake, egg weight, egg index, yolk index, Haugh unit, egg shell weight and egg shell thickness. Feeding LEO, individually or in combination with MEO, did not affect FCR compared with the control group (p < .05), however, feeding MEO individually increased feed conversation ratio (FCR) compared to LEO and the control group during 42–56 weeks (p < .05), as well as decreasing egg mass compared to LEO (p < .05). Feeding LEO increased egg production compared to MEO and combination of MEO and LEO (p < .05).

Conclusions

In conclusion, dietary supplemental MEO (250 mg/kg) may increase FCR, and LEO (250 mg/kg) is more effective than MEO (250 mg/kg) for egg production and egg mass purposes; besides MEO (250 mg/kg) negatively affected FCR compared with the control group. In addition, no specific beneficial effect of dietary supplemental MEO and/or LEO on the other measured variables was detected.

Effects of using essential oil of Lavandula stoechas in quail feed on growth performance, carcass characteristics, meat quality, and health status

Aim:

The aim of this study was to determine the effects of essential oil of Lavandula stoechas (Lavender) on growth performance, carcass characteristics, meat quality, and health status of quails.

Materials and Methods:

A group of 600 1-day-old Japanese quail chicks (Coturnix japonica), with an average weight of 6.8±0.2 g and a 1:1 sex ratio, were randomly assigned to four groups (150 chicks/group): three experimental groups which depend on the incorporation of lavender oil (LO) in the different phases of breeding and one control group. The experimental groups received a supplement of 1 g LO per kg of feed distributed sequentially throughout the entire 42-day breeding period.

Results:

No deaths were recorded throughout the breeding period. Highly significant differences were observed among the groups with regard to body weight measured on day 20 and day 42 (p<0.001 and p<0.01, respectively). The addition of LO was accompanied by reductions in liver weights; furthermore, LO had a significant effect on the pH, water content, and fat content of the meat (p<0.05). Administration of LO had a measurable effect on the endogenous intestinal population of Lactobacillus, and the bacterial load (including those of Escherichia coli and Staphylococcus aureus) was significantly reduced.

Conclusions:

Our results demonstrate that supplementing quail feed with LO has a profound effect on their growth as well as antimicrobial effects.

Improvement of eggshell quality by dietary N-carbamylglutamate supplementation in laying chickens

Egg quality defects seriously reduce the quality grade and increase egg breakage in egg marketing activities. In this study, the effect of N-carbamylglutamate (NCG) on eggshell quality was investigated by evaluating calcium absorption and calcification in laying hens. A total of 30 newly hatched female Hy-Line chicks were randomly assigned to the control group (basal diet) and treatment group (basal diet supplemented with 1% NCG). At 25 wk, eggs from each group were obtained to assess egg quality parameters. Blood samples were collected for analysis of mineral, hormone, and amino acids levels at 16 h after laying egg. Uterine tissues were removed and fixed in 4% neutral paraformaldehyde solution or kept in liquid nitrogen for mineral determination, quantitative PCR, and Western blot. Results showed that the egg quality (eggshell thickness, strength and percentage, egg specific gravity, and eggshell effective thickness) was significantly increased while effective thickness of mastoid layer, width of mastoid gap, and mammillary knobs were significantly decreased by dietary NCG supplementation (P < 0.05). The levels of minerals (Ca, P, Fe, Mg, Na, K) in eggshell, plasma, and uterus were remarkably elevated (P < 0.05). Meanwhile, the concentrations of calcium metabolism-related hormones (17β-estradiol, parathyroid hormone, and calcitonin) were increased in the NCG group (P < 0.05). Moreover, expression of calbindin 1, carbonic anhydrase 2, ovalbumin, ovotransferrin, ovocleidin-17, ovocleidin-116, and clusterin mRNAs, as well as calbindin 1 and ATP2A1 proteins in uterus, duodenum, and kidney, was all upregulated in hens fed with NCG (P < 0.05). In addition, the number of blood vessels in the uterus, height of uterine mucosal folds, villus length in endometrium, and areas of uterine mucosal folds were significantly increased in the NCG group (P < 0.05). In conclusion, dietary 1% NCG supplementation during 0 to 25 wk can improve eggshell quality through changes in endometrial morphology, expression of calcium metabolism-related genes, and secretion of related hormones to promote eggshell formation in the laying hens.

Dietary betaine supplementation improves meat quality of transported broilers through altering muscle anaerobic glycolysis and antioxidant capacity

BACKGROUND

To investigate the effect of dietary betaine supplementation on growth performance, meat quality, muscle anaerobic glycolysis and antioxidant capacity of transported broilers, 1-day-old partridge-shank-broiler-chickens (n = 192) were randomly divided into three groups for a 50-day feeding trial. The broilers in the control group were fed a basal diet, and experienced 0.75-h transport before slaughter. The broilers in the other three groups were fed a basal diet supplemented with 0, 500 or 1000 mg kg^-1 betaine, respectively, and experienced 3-h transport before slaughter (T, T + BET₅₀₀ or T + BET₁₀₀₀ groups).

RESULTS

Dietary betaine supplementation increased (P < 0.05) average daily gain of broilers, and feed conversion ratio was also improved (P < 0.05) by 500 mg kg^-1 betaine supplementation. Compared with the control group, 3-h transport increased (P < 0.05) live weight loss, serum corticosterone and cortisol concentrations, as well as muscle lactate and malondialdehyde (MDA) contents, and decreased (P < 0.05) muscle pH_24h , glycogen content and total superoxide dismutase activity. Compared with the T group, betaine supplementation decreased (P < 0.05) serum corticosterone and cortisol concentrations and muscle MDA content, and increased (P < 0.05) muscle a*_24 h . In addition, 1000 mg kg^-1 betaine supplementation further decreased (P < 0.05) muscle drip loss, lactate content and lactate dehydrogenase activity, and increased (P < 0.05) muscle glutathione content and glutathione peroxidase activity.

CONCLUSION

Betaine supplementation not only improved growth performance of broilers, but also alleviated meat quality deterioration of transported broilers through altering muscle anaerobic glycolysis and antioxidant capacity. © 2020 Society of Chemical Industry.

The effect of avocado seed powder (Persea americana Mill.) on the liver and kidney functions and meat quality of culled female quail (Coturnix coturnix japonica)

Background and Aim:

High temperatures have a detrimental effect on quail performance, even disrupting the immune system and function of the internal organs. This research aimed to investigate the effectiveness of avocado seed powder supplements on meat quality and the liver and kidney functions of culled female quails.

Materials and Methods:

A total of 100 six-month-old culled female quail were allotted to four dietary treatments, i.e., R0: Basal feed without avocado seed powder supplement and R1, R2, and R3 with basal feed + 3%, 6%, and 9% avocado seed powder supplement, respectively. The observed variables included meat quality (protein, fat, cholesterol and meat collagen, water holding capacity, and tenderness), liver function (liver weight, serum glutamic oxaloacetic transaminase [SGOT], and serum glutamic pyruvate transaminase [SGPT]), and kidney function (urea level, creatinine, uric acid, albumin, and glucose).

Results:

Analysis of variance showed that avocado seed powder supplements significantly affected the level of SGOT, urea, creatinine, protein, fat, cholesterol, meat tenderness, and cooking loss. A non-significant effect was found on liver weight, SGPT, uric acid, albumin and glucose blood level, collagen, or water holding capacity level.

Conclusion:

Avocado seed powder supplements improved meat quality as well as the liver and kidney functions of the culled female quail.