Effect of Dietary Rhodobacter capsulatus on Egg-Yolk Cholesterol and Laying Hen Performance

Effects of dietary supplementation with tea polyphenols and probiotics on laying performance, biochemical parameters intestinal morphology and microflora of laying hens

This study was conducted to investigate the effects of tea polyphenols (TP) and probiotics (PB) on the production performance, biochemical indices, and gut health of laying hens. A total of 400 Hy-line Brown layers (45 weeks old) were randomly assigned to 8 diet groups for 8-week feeding trial. Compared with the control basal diet (CT), dietary high dosage of TP and PB (HTP-PB) increased egg mass (P < 0.05). Supplementation with HTP-PB improved the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and decreased the malonic dialdehyde (MDA) content (P < 0.05) without affecting the contents of immunoglobulins in the serum. The combination of HTP and PB supplementation promoted the secretion of estradiol (E2) and progesterone (PROG) compared with treatment with TP or PB alone (P < 0.05). The combined use of HTP and PB induced higher jejunal villus height (VH) than the CT group (P < 0.05). Dietary TP and PB could optimize the functional network of intestinal microflora and the interactions between the intestinal microflora and the host. Therefore, the combined use of the high dosage of TP and PB affected laying performance, improved antioxidant capacity, and promoted intestinal health, which may be associated with regulation of the intestinal microbiota.

Body Metrics and the Gut Microbiome in Response to Macronutrient Limitation in the Zebrafish Danio rerio

Background

Healthy and predictable physiologic homeostasis is paramount in animal models for biomedical research. Proper macronutrient intake is an essential and controllable environmental factor for maintaining animal health and promoting experimental reproducibility.

Objective and Methods

Evaluate reductions in dietary macronutrient composition on body weight metrics, composition, and gut microbiome in Danio rerio.

Methods

D. rerio were fed reference diets deficient in either protein or lipid content for 14 weeks.

Results

Diets of reduced-protein or reduced-fat resulted in lower weight gain than the standard reference diet in male and female D. rerio. Females fed the reduced-protein diet had increased total body lipid, suggesting increased adiposity compared with females fed the standard reference diet. In contrast, females fed the reduced-fat diet had decreased total body lipid compared with females fed the standard reference diet. The microbial community in male and female D. rerio fed the standard reference diet displayed high abundances of Aeromonas, Rhodobacteraceae, and Vibrio. In contrast, Vibrio spp. were dominant in male and female D. rerio fed a reduced-protein diet, whereas Pseudomonas displayed heightened abundance when fed the reduced-fat diet. Predicted functional metagenomics of microbial communities (PICRUSt2) revealed a 3- to 4-fold increase in the KEGG (Kyoto Encyclopedia of Genes and Genomes) functional category of steroid hormone biosynthesis in both male and female D. rerio fed a reduced-protein diet. In contrast, an upregulation of secondary bile acid biosynthesis and synthesis and degradation of ketone bodies was concomitant with a downregulation in steroid hormone biosynthesis in females fed a reduced-fat diet.

Conclusions

These study outcomes provide insight into future investigations to understand nutrient requirements to optimize growth, reproductive, and health demographics to microbial populations and metabolism in the D. rerio gut ecosystem. These evaluations are critical in understanding the maintenance of steady-state physiologic and metabolic homeostasis in D. rerio. Curr Dev Nutr 20xx;x:xx.

Low particle concentrations of nanoplastics impair the gut health of medaka

The environmental occurrence of nanoplastics (NPs) is now evident but their long-term impacts on organisms are unclear, limiting ecological and health risk assessment. We hypothesized that chronic exposure to low particle concentrations of NPs can result in gut-associated toxicity, and subsequently affect survival of fish. Japanese medaka Oryzias latipes were exposed to polystyrene NPs (diameter 100 nm; 0, 10, 10⁴, and 10⁶ items/L) for 3 months, and histopathology, digestive and antioxidant enzymes, immunity, intestinal permeability, gut microbiota, and mortality were assessed. NP exposures caused intestinal lesions, and increased intestinal permeability of the gut. The trypsin, lipase, and chymotrypsin activities were increased, but the amylase activity was decreased. Oxidative damage was reflected by the decreased superoxide dismutase and alkaline phosphatase and increased malondialdehyde, catalase, and lysozyme. The integrated biomarkers response index values of all NP-exposed medaka were significantly increased compared to the control group. Moreover, NP exposures resulted in a decrease of diversity and changed the intestinal microbiota composition. Our results provide new evidence that long-term NPs exposure impaired the health of fish at extremely low particle concentrations, suggesting the need for long-term toxicological studies resembling environmental particle concentrations when assessing the risk of NPs.

Changes of the intestinal microbiota along the gut of Japanese Eel (Anguilla japonica)

Fish intestine contains different types of microbiomes, and bacteria are the dominant microbiota in fishes. Studies have identified various core gut bacteria in fishes. However, little is known about the composition and their relative functions of gut microbial community along the intestine. To explore this, the current study investigated the microbial community distribution along the gut in Anguilla japonica. By 16S rRNA gene sequencing, we profiled the gut microbiota in eel along the three regions (anterior intestine (AI), the middle intestine (MI) and the posterior intestine (PI)). Results suggested that the three regions did not have significant differences on the observed species and diversities. The cluster tree analysis showed that the bacteria community in MI was closer to PI than the AI. The dominant bacteria in AI were the Proteobacteria, in which the majority was graduated replaced by Bacteroidetes along the gut to PI region. Through PICRUSt analysis, shifts in the bacterial community along the gut were found to affect the genetic information processing pathways. Higher levels of translation and transcriptional pathway activities were found in MI and PI than in AI. The dominant bacterial species were different among the regions and contributed to various biological functions along the gut.

Probiotics-Live Biotherapeutics: a Story of Success, Limitations, and Future Prospects-Not Only for Humans

In livestock production, lactic acid bacteria (LAB) represent the most widespread microorganisms used as probiotics. For such critical use, these bacteria must be correctly identified and characterized to ensure their safety and efficiency. Recently, probiotics have become highly recognized as supplements for humans and in particular for animals because of their beneficial outcome on health improvement and well-being maintenance. Various factors, encompassing dietary and management constraints, have been demonstrated to tremendously influence the structure, composition, and activities of gut microbial communities in farm animals. Previous investigations reported the potential of probiotics in animal diets and nutrition. But a high rate of inconsistency in the efficiency of probiotics has been reported. This may be due, in a major part, to the dynamics of the gastrointestinal microbial communities. Under stressing surroundings, the direct-fed microbials may play a key role as the salient limiting factor of the severity of the dysbiosis caused by disruption of the normal intestinal balance. Probiotics are live microorganisms, which confer health benefits on the host by positively modifying the intestinal microflora. Thus, the aim of this review is to summarize and to highlight the positive influence of probiotics and potential probiotic microbe supplementation in animal feed with mention of several limitations.

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

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

Effects of chemical silage of red tilapia viscera (Oreochromis spp.) as a source of protein on the productive and hematological parameters in isa-brown laying hens (Gallus gallus domesticus)

This paper evaluates the inclusion of chemical silage from viscera of red tilapia (Oreochromis spp.) in diets of Isa-Brown laying hens (Gallus gallus domesticus), and its influence on productive variables and hematological parameters. A total of 56, 16-week-old laying hens were randomly divided into two groups (one per diet), which in turn were subdivided into 7 replicates of 4 birds each. All test groups were fed for 16 weeks. During this period, the evaluation of the productive variables was carried out, and at the end, random blood samples were taken from 3 birds per diet. The results indicated that the inclusion of chemical silage from red tilapia viscera with a proportion of 17.18% dry matter, does not present statistically significant differences in the productive variables which were evaluated (p > 0.05) with respect to the control. Moreover, the chemical silage did not modify the hematological parameters and blood the chemistry in the hens. This allowed us to conclude that silage can be used as a substitute for conventional protein raw materials such as fishmeal and soybean meal in the preparation of diets for laying hens, without altering their productive performance.

Dietary choline supplementation regulated lipid profiles of egg yolk, blood, and liver and improved hepatic redox status in laying hens

Five hundred and forty 19-wk-old HyLine Brown laying hens were randomly distributed to 6 dietary treatments and fed 1of 6 corn-soybean meal-based diets added into choline with 0, 425, 850, 1,700, 3,400, and 6,800 mg/kg to investigate effects of dietary choline supplementation on lipid profiles of egg yolk, serum and liver, and hepatic redox status of laying hens. Yolk weight and total lipid, triglyceride, cholesterol and phosphatidylcholine, serum triglyceride, cholesterol, apolipoprotein B 100 (apoB 100), and very low density lipoprotein (VLDL), and liver relative weight, total lipid, triglyceride and apoB 100 as well as hepatic total superoxide dismutase and glutathione peroxidase (GSH-Px) activities, total antioxidant capacity (T-AOC), and malondialdehyde (MDA) in laying hens at weeks 58 and 68 of age were determined. The differences (P < 0.001) were caused by choline treatments in yolk phosphatidylcholine (at 850 mg/kg or more choline), serum VLDL, and liver triglyceride (at 1,700 and 3,400 mg/kg choline) of birds, at weeks 58 and 68 of age, and yolk total lipids were elevated (P < 0.05) by supplemental choline at 3,400 mg/kg whereas liver total lipids were reduced (P < 0.05) by 1,700 and 3,400 mg/kg choline addition. Hens fed diets supplemented choline had higher (P = 0.005) liver GSH-Px activity (with 3,400 mg/kg choline) and greater (P = 0.014) T-AOC (with 1,700 mg/kg choline) than those fed diets with 0 and 425 mg/kg choline addition. Choline affected serum VLDL, liver total lipid, triglyceride and apoB 100 at weeks 58 and 68 of age and hepatic GSH-Px activity, T-AOC and MDA at week 68 of age quadratically (P < 0.05), whereas it influenced total lipid and phosphatidylcholine of egg yolk linearly (P < 0.05) and quadratically (P < 0.05). In conclusion, dietary choline supplementation elevated yolk total lipid and phosphatidylcholine and serum VLDL, reduced liver total lipid and triglyceride, and enhanced hepatic GSH-Px activity and T-AOC in laying hens.

Polystyrene microplastics induce microbiota dysbiosis and inflammation in the gut of adult zebrafish

Microplastic (MP) are environmental pollutants and have the potential to cause varying degrees of aquatic toxicity. In this study, the effects on gut microbiota of adult male zebrafish exposed for 14 days to 100 and 1000 μg/L of two sizes of polystyrene MP were evaluated. Both 0.5 and 50 μm-diameter spherical polystyrene MP increased the volume of mucus in the gut at a concentration of 1000 μg/L (about 1.456 × 10¹⁰ particles/L for 0.5 μm and 1.456 × 10⁴ particles/L for 50 μm). At the phylum level, the abundance of Bacteroidetes and Proteobacteria decreased significantly and the abundance of Firmicutes increased significantly in the gut after 14-day exposure to 1000 μg/L of both sizes of polystyrene MP. In addition, high throughput sequencing of the 16S rRNA gene V3-V4 region revealed a significant change in the richness and diversity of microbiota in the gut of polystyrene MP-exposed zebrafish. A more in depth analysis, at the genus level, revealed that a total of 29 gut microbes identified by operational taxonomic unit (OTU) analysis were significantly changed in both 0.5 and 50 μm-diameter polystyrene MP-treated groups. Moreover, it was observed that 0.5 μm polystyrene MP not only increased mRNA levels of IL1α, IL1β and IFN but also their protein levels in the gut, indicating that inflammation occurred after polystyrene MP exposure. Our findings suggest that polystyrene MP could induce microbiota dysbiosis and inflammation in the gut of adult zebrafish.

Imazalil exposure induces gut microbiota dysbiosis and hepatic metabolism disorder in zebrafish

The fungicide imazalil (IMZ) is used extensively to preserve freshness, prevent decay and control fungal infections in fruits, vegetables or other plants. Recently, some studies have reported that the real in aquatic systems have reached very high levels. Here, male adult zebrafish were exposed to 100 and 1000μg/L IMZ for 1, 7, 21days, and the gut microbiota and hepatic metabolism were evaluated. Exposure to a high concentration of IMZ for 21days decreased mucin secretion in the gut. Sequencing of the V3-V4 region of the bacterial 16S rRNA gene revealed a significant increase in the diversity of gut microbiota in male zebrafish. At the phylum level, the composition of Proteobacteria and Bacteroidetes was decreased, while those Fusobacteria and Firmicutes increased in the gut after exposure to 1000μg/L IMZ for 21days. At the genus level, 29 species of microorganisms were significantly changed after IMZ exposure. Based on GC/MS metabolomics analysis, 101 metabolites were observably significantly altered in the 1000μg/L IMZ-treatment group. These changed metabolites were mainly associated with the pathway of glycolysis, amino acid metabolism, and lipid metabolism. In addition, the transcription of some genes related to glycolysis and lipid metabolism, including Aco, Cpt1, Acc1, Srebp1a and Fas, was decreased significantly in the liver of zebrafish when exposed to 100 and 1000μg/L IMZ for 7 or 21days. These results indicated that exposure to IMZ could cause gut microbiota dysbiosis and metabolic disorders in adult zebrafish.

Physicochemical and Functional Characterization of Blue-Shelled Eggs in Korea

The aim of this study was to compare the quality and physicochemical characteristics of blue-shelled eggs (BE) and conventional eggs (CE). Proximate composition, quality, pH value, shell color, collagen content, fatty acid composition, total cholesterol, α-glucosidase inhibition activity, and antioxidation activity were determined. The proximate composition, general qualities, and pH values of CE and BE showed no significant differences, except in moisture composition, weight, and shell thickness. Moisture content and weight of BE were significantly lower than those of CE. However, shell thickness and weight of BE were higher than those of CE (p<0.05). Lightness of BE was significantly higher than that of CE (85.20 vs. 58.80), while redness (a*) and yellowness (b*) of BE were lower than those of CE (a*: −4.75 vs. 14.20; b*: 10.45 vs. 30.63). The fatty acid [C18:1n7 (cis-vaccenic acid) and C18:3n6 (gamma-linolenic acid)] contents of BE were significantly higher than those of CE. The total cholesterol contents of BE and CE were similar. DPPH radical scavenging activity of BE was significantly higher than that of CE (40.78 vs. 35.35). Interestingly, α-glucosidase inhibition activity of whole egg and egg yolk in BE (19.27 and 36.06) was significantly higher than that of whole egg and egg yolk in CE (13.95 and 32.46). This result indicated that BE could potentially be used as a functional food material. Further studies are required to evaluate the specific compounds that affect functional activity.

Metagenomics approach to the study of the gut microbiome structure and function in zebrafish Danio rerio fed with gluten formulated diet

In this study, we report the gut microbial composition and predictive functional profiles of zebrafish, Danio rerio, fed with a control formulated diet (CFD), and a gluten formulated diet (GFD) using a metagenomics approach and bioinformatics tools. The microbial communities of the GFD-fed D. rerio displayed heightened abundances of Legionellales, Rhizobiaceae, and Rhodobacter, as compared to the CFD-fed counterparts. Predicted metagenomics of microbial communities (PICRUSt) in GFD-fed D. rerio showed KEGG functional categories corresponding to bile secretion, secondary bile acid biosynthesis, and the metabolism of glycine, serine, and threonine. The CFD-fed D. rerio exhibited KEGG functional categories of bacteria-mediated cobalamin biosynthesis, which was supported by the presence of cobalamin synthesizers such as Bacteroides and Lactobacillus. Though these bacteria were absent in GFD-fed D. rerio, a comparable level of the cobalamin biosynthesis KEGG functional category was observed, which could be contributed by the compensatory enrichment of Cetobacterium. Based on these results, we conclude D. rerio to be a suitable alternative animal model for the use of a targeted metagenomics approach along with bioinformatics tools to further investigate the relationship between the gluten diet and microbiome profile in the gut ecosystem leading to gastrointestinal diseases and other undesired adverse health effects.

Biomass recovery during municipal wastewater treatment using photosynthetic bacteria and prospect of production of single cell protein for feedstuff

Utilization of photosynthetic bacteria (PSB) for wastewater treatment and production of biomass for economical single cell protein production is a feasible option. In this study, Rhodopseudomonas sp. CSK01 was used for municipal wastewater treatment and the effect of initial pH, light intensity and additional carbon source was investigated. Optimum chemical oxygen demand (COD) removal and biomass production were achieved when the initial pH and light intensity were 7 and 4000 lux, respectively. The specific growth rate, biomass yield and biomass productivity were found to be 0.4/d, 3.2 g/g COD and 2.1 g/L/d, respectively, which were improved by 100%, 167% and 200% relative to the original condition. Under the optimal conditions, COD removal reached 85% and maximum biomass was 6.2 g/L accomplished within three days of cultivation. The biomass had a relatively high protein content (60.1%) consisting of all essential amino acids. The contents of histidine, lysine, phenylalanine and leucine were superior to those of the previously described PSB. Results showed that COD removal was not improved in the presence of additional carbon sources (glucose, sucrose and malic acid). The addition of malic acid significantly increased the biomass accumulation by 279% relative to the original condition, whereas COD removal was declined due to carbon catabolite repression. In this study, PSB biomass recovery and catabolite repression are proposed in municipal wastewater treatment by Rhodopseudomonas sp.

Effects of dietary supplementation with Gynura procumbens (Merr.) on egg yolk cholesterol, excreta microflora and laying hen performance

Abstract 1. The present study investigated the effects of dietary supplementation with Gynura procumbens on egg yolk and serum cholesterol and triglycerides, excreta microflora, laying performance and egg quality. 2. A total of 160 Hy-Line Brown layers (45 weeks old) were randomly assigned into 4 treatments on the basis of laying performance. Each treatment had 4 replicates with 10 birds each. 3. Dietary treatments were basal diet supplemented with 0 (control), 2.5, 5.0 and 7.5 g/kg diet G. procumbens during 56-d feeding period. 4. Serum (d 21, 42 and 56) and egg yolk (d 28, 42 and 56) cholesterol and triglycerides concentrations were linearly reduced with increasing dietary concentrations of G. procumbens. 5. Increasing dietary concentrations of G. procumbens linearly reduced the excreta total anaerobic bacteria (d 28), Clostridium sp. and Escherichia coli (d 28 and 56) populations. 6. Overall egg production and egg mass were linearly increased, and overall feed efficiency was linearly improved with increase in dietary G. procumbens. 7. Dietary increasing concentrations of G. procumbens linearly improved egg yolk colour (d 28 and 56) and breaking strength of eggs (d 56). 8. The results obtained in the present experiment indicate that dietary supplementation with G. procumbens could reduce the egg yolk cholesterol, suppresses harmful excreta microflora and improves layers performance.

The Effects of Rhodobacter capsulatus KCTC-2583 on Cholesterol Metabolism, Egg Production and Quality Parameters during the Late Laying Periods in Hens

An experiment was conducted to investigate the effects of dietary supplementation of Rhodobacter capsulatus KCTC-2583 on egg-yolk and serum cholesterol, egg production and quality parameters during the late laying periods in hens. A total of 160 Hy-Line Brown layers (54 wk-old) were randomly allotted to 4 treatment groups on the basis of laying performance. Each treatment had 4 replicates with 10 birds each (40 birds per treatment). Two hens were confined individually with cage size 35×35×40 cm and each 10 birds (5 cages) shared a common feed trough between them forming one experimental unit. Dietary treatments were; basal diet supplemented with 0 (control), 0.05, 0.10 and 0.15% R. capsulatus KCTC-2583. Experimental diets were fed in meal form for 56 d. Dietary supplementation of increasing levels of R. capsulatus KCTC-2583 reduced (linear, p<0.05) egg-yolk cholesterol and triglycerides (d 28, 42 and 56) concentrations. Also, serum cholesterol and triglycerides (d 21, 42 and 56) concentrations were linearly reduced (p<0.05) with increasing dietary R. capsulatus KCTC-2583. Laying hens fed a diet supplemented with increasing levels of R. capsulatus KCTC-2583 had increased (linear; p<0.05) overall egg production, egg weight, egg mass and feed efficiency. However, dietary treatments had no effect (linear or quadratic; p>0.05) on feed intake of laying hens. At d 28 and 56, breaking strength and yolk colour of eggs were linearly improved (p<0.05) in laying hens fed dietary increasing levels of R. capsulatus KCTC-2583. Dietary treatment had no effects (linear or quadratic; p>0.05) on albumin height, shell thickness and shell weight at any period of experiment. These results indicate that dietary supplementation of R. capsulatus KCTC-2583 has the potential to improve the laying hen performance and lead to the development of low cholesterol eggs during late laying period in Hy-Line Brown hens.

Lesser known indigenous vegetables as potential natural egg colourant in laying chickens

Background

A six-week study involving two hundred and fifty (250) Harco Black layer birds at point of lay was conducted to investigate the effects of potential natural colorant on performance and Egg quality traits. The birds were assigned to five (5) dietary treatments, each containing supplements either of control, Baobab Leaf (BL), Waterleaf (WL), Red Pepper (RP), Canthaxanthin (CTX) at 40 g/kg feed and 50 mg/kg feed of natural and commercial colorants, respectively.

Results

Performance records shows that there was no significant (p > 0.05) difference in feed intake across the supplements of Red pepper, Water leaf, Canthaxanthin and control diet, however, birds fed Baobab leaf treatment had a significantly lower (p < 0.05) feed intake value (94.07 g) when compared with other treatments. Body weight gain and Hen Day Production were not significant influenced (p > 0.05) by the dietary treatments, although laying hens fed Baobab leaf supplement had lowest mean HDP of 48.80%, while birds fed Red pepper and Water leaf supplement had an average value of 52.79%. There was no significant effect (p > 0.05) of colorants on egg external traits, compared with the control; birds fed Canthaxanthin treatment had higher mean egg weight (51.79 g), egg length (4.55 g), egg breadth (3.29 g); Red pepper treatment had highest mean shell thickness (0.29 g), however these differences were not significant (p > 0.05). Yolk height, Albumen height, Yolk index, and Haugh unit were not significantly affected (p > 0.05) across treatments. Yolk width was lowest (p < 0.05) in Baobab leaf treatment (2.54 cm); Red pepper, Water leaf and Canthaxanthin (2.89 cm, 2.62 cm and 2.89 cm respectively) were not significantly (p > 0.05) different from the control (2.73 cm). Yolk colour score was significantly highest (p < 0.05) in Red pepper treatment (7.50); Water leaf, Baobab leaf and Canthaxanthin ranged between 2.25- 3.31 on the DSM yolk colour fan, Control treatment had the lowest yolk colour score (p < 0.05) of 1.31.

Conclusion

The study showed Red pepper as a worthy alternative to commercial yolk colorant. Water leaf and baobab are not good substitutes for canthaxanthin as a yolk colourant.

Characteristics of purple nonsulfur bacteria grown under Stevia residue extractions

As a consequence of the large-scale cultivation of Stevia plants, releases of plant residues, the byproduct after sweetener extraction, to the environment are inevitable. Stevia residue and its effluent after batching up contain large amounts of organic matters with small molecular weight, which therefore are a potential pollution source. Meanwhile, they are favourite substrates for micro-organism growths. This investigation was aimed to utilize the simulated effluent of Stevia residue to enrich the representative purple nonsulfur bacterium (PNSB), Rhodopseudomonas palustris (Rps. palustris), which has important economic values. The growth profile and quality of Rps. palustris were characterized by spectrophotometry, compared to those grown in common PNSB mineral synthetic medium. Our results revealed that the simulated effluent of Stevia residue not only stimulated Rps. palustris growth to a greater extent, but also increased its physiologically active cytochrome concentrations and excreted indole-3-acetic acid (IAA) content. This variation in phenotype of Rps. palustris could result from the shift in its genotype, further revealed by the repetitive sequence-based PCR (rep-PCR) fingerprinting analysis. Our results showed that the effluent of Stevia residue was a promising substrate for microbial growth.

Effects of diets supplemented with zinc and manganese on performance and related parameters in laying hens

Iron is often found to be of excessive concentrations in laying hens' diets, which may cause antagonistic interactions with other minerals. This study was conducted to investigate how to supplement Zn and Mn in the diets without Fe supplementation. In experiment 1, 420 18-week Lohmann Brown layers were fed a basal diet or a basal diet supplemented with 30-0, 65-30 and 100-60 mg/kg of Zn and Mn, respectively. In experiment 2, 360 40-week Lohmann Brown layers were fed a basal diet or a basal diet supplemented with 15-0, 35-0 and 55-15 mg/kg of Mn and Zn, respectively. Minerals were supplemented in the form of sulfate. Egg production was improved by supplementing 30 mg/kg Zn or 65 mg/kg Zn in combination with 30 mg/kg Mn in experiment one. In experiment two, a significant reduction of egg performance occurred with 35 mg/kg Mn supplementation. Mn and/or Zn supplementation increased eggshell thickness in experiment one, and decreased yolk cholesterol in both experiments. Mn and/or Zn supplementation increased Zn and Mn excretion in both experiments. Serum growth hormone (GH), thyroxine (T(4) ), and insulin levels, or alkaline phosphatase (AP) activity were not affected by treatments; serum estrogen (E(2) ) and triiodothyronine (T(3) ) were different but there was no consistency by dietary treatments. This study demonstrates that 30 mg/kg supplemental Zn is necessary to obtain maximal egg production, and there seems to be no need to supply Mn in this type of diet.

Effect of selenium-enriched probiotics on laying performance, egg quality, egg selenium content, and egg glutathione peroxidase activity

A 35-day experiment was conducted to evaluate the effect of selenium-enriched probiotics (SP) on laying performance, egg quality, egg selenium (Se) content, and egg glutathione peroxidase (GPX) activity. Five hundred 58-week-old Rohman laying hens were randomly allotted to 5 dietary treatments of 100 each. Each treatment had 5 replicates, and each replicate had 5 cages with 4 hens per cage. The SP was supplemented to a corn-soybean-meal basal diet at 3 different levels that supplied total Se at 0.2, 0.5, and 1.0 mg/kg. The basal diet served as a blank control, while the basal diet with supplemental probiotics served as a probiotics control. The results showed that dietary SP supplementation not only increased (p < 0.05) the rate of egg laying, day egg weight, mean egg weight, egg Se content, and egg GPX activity but also decreased (p < 0.05) the feed:egg ratio and egg cholesterol content. The egg Se content was gradually increased (p < 0.05) along with the increasing level of dietary Se. The SP supplementation also slowed down (p < 0.05) the drop of Haugh units (HU) of eggs stored at room temperature. The egg GPX activity had a positive correlation (p < 0.01) with egg Se content and a negative correlation (p < 0.01) with egg HU drop. These results suggested that Se contents, GPX activity, and HU of eggs were affected by the dietary Se level, whereas the egg-laying performance and egg cholesterol content were affected by the dietary probiotics. It was concluded that this SP is an effective feed additive that combines the organic Se benefit for hen and human health with the probiotics benefit for laying hen production performance. It was also suggested that the eggs from hens fed this SP can serve as a nutraceutical food with high Se and low cholesterol contents for both healthy people and patients with hyperlipidemia, fatty liver, or cardiovascular disease.

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

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

Effects of ginger root (Zingiber officinale) on laying performance and antioxidant status of laying hens and on dietary oxidation stability

To investigate the effects of ginger root (Zingiber officinale) on laying performance and antioxidant status of laying hens and on dietary oxidation stability, 675 Hy-Line brown laying hens at 27 wk of age were randomly allocated to 5 treatments with 5 replicates in a complete randomized design. Laying hens were fed corn-soybean meal based diets and supplemented with 0, 5, 10, 15, or 20 g of ginger powder/kg of diet for 10 wk. The ADFI, laying rate, average egg weight, egg mass, and feed conversion of each replicate were measured weekly. Blood samples from 10 laying hens and 15 egg samples/treatment were obtained on d 35 and 70 of the experiment to determine the serum or egg yolk antioxidant enzymatic activities. Three separate batches of each treatment diet were also made at the beginning of the experiment and stored at 20°C. Subsamples were taken at 10-d intervals to determine the dietary oxidation stability over a 60-d period. All laying hens had similar ADFI, laying rate, average egg weight, and feed conversion. However, laying hens supplemented with ginger powder had higher (P = 0.024) egg mass than the control group. Supplementation of ginger powder increased (P < 0.05) the serum and egg yolk antioxidant enzymatic activities of laying hens on d 35 and 70. Increasing ginger powder from 0 to 20 g/kg of diet linearly increased (P < 0.05) the peroxide value but linearly reduced (P < 0.05) the acid value of lipid extracted from stored diets for the first 30 d, but not for the second 30 d. Dietary supplementation of ginger powder improved laying performance and serum and egg yolk antioxidant status and enhanced dietary oxidation stability in a dose-dependent manner. The optimum supplementation rate of ginger powder in the diet of laying hens appeared to be between 10 and 15 g/kg of diet.

Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens

1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality.

Effects of Enterococcus faecium M 74 strain on selected blood and production parameters of laying hens

1. The aim was to evaluate the functional efficiency of a probiotic strain Enterococcus faecium M 74 in the feed on selected biochemical, haematological and production parameters of ISA Brown hens. 2. Feed in the experimental group was enriched with a probiotic preparation containing of 5 × 10(9) viable E. faecium M 74 per g. Blood samples were collected during the egg-laying period at 5 (w5), 25 (w25) and 45 (w45) weeks of production. Body weight, rate of lay and egg weight were recorded every 4 weeks during the 48-week laying period. 3. Significantly lower concentrations of total cholesterol and total lipids in blood plasma were observed in the experimental group at all sampling times compared with their respective controls. Concentrations of triglycerides did not differ. Significantly lower concentrations of plasma calcium were found in the experimental group at w5 and w45. Concentrations of inorganic phosphorus in the experimental group were significantly higher at w25, but significantly lower at w45. Erythrocyte count was significantly higher in the experimental group at w25 and w45 when compared with controls. Leucocyte counts were significantly lower in the experimental group at all sampling times. Significantly lower values of haematocrit at w5 and w45 were observed in the experimental group than in controls. Body weight, the number of eggs and average egg weight were not significantly affected by probiotic addition. 4. In conclusion, the addition of probiotic strain E. faecium M 74 to the feed of ISA Brown hens reduced cholesterol, lipids, calcium, leucocyte counts and haematocrit values in blood plasma in at least two sampling times, while erythrocyte counts were increased. No significant effects of probiotic on triglyceride concentration and egg production parameters were observed.

Effects of karaya saponin and Rhodobacter capsulatus on yolk cholesterol in laying hens

1. It has been reported that karaya saponin and Rhodobacter capsulatus individually have hypocholesterolaemic activity in laying hens. This study focuses on the effect of adding karaya saponin with R. capsulatus to hen's diet with regard to serum and egg yolk cholesterol and triglycerides. 2. A total of 56 Boris Brown laying hens were divided into 7 groups at 20 weeks of age. Combinations of 25, 50, 75 mg kg(-1) karaya saponin and R. capsulatus 200 and 400 mg kg(-1) were used as treatment groups. 3. After 8 weeks of supplementation, the effects of all the combinations of karaya saponin and R. capsulatus on serum and egg yolk cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol were greater than either karaya saponin or R. capsulatus alone. The combination of karaya saponin 50 mg kg(-1)+ R. capsulatus 400 mg kg(-1) exhibited the greatest reduction of serum (325%) and yolk (225%) cholesterol and the greatest increase of faecal, liver bile acids and yolk fatty acid (oleic, linoleic and linolenic) concentrations. In addition, egg production and yolk colour were significantly improved by the combined use of karaya saponin and R. capsulatus supplementation. 4. Therefore, the dietary supplementation of karaya saponin and R. capsulatus may lead to the production of a low-cholesterol egg, with production performance maintained at a standard level.

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

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

Dietary Karaya Saponin and Rhodobacter capsulatus Exert Hypocholesterolemic Effects by Suppression of Hepatic Cholesterol Synthesis and Promotion of Bile Acid Synthesis in Laying Hens

This study was conducted to elucidate the mechanism underlying the hypolipidemic action of karaya saponin or Rhodobacter (R.) capsulatus. A total of 40 laying hens (20-week-old) were assigned into four dietary treatment groups and fed a basal diet (as a control) or basal diets supplemented with either karaya saponin, R. capsulatus, or both for 60 days. The level of serum low-density-lipoprotein cholesterol and the levels of cholesterol and triglycerides in the serum, liver, and egg yolk were reduced by all the supplementations (P < .05). Liver bile acid concentration and fecal concentrations of cholesterol, triacylglycerol, and bile acid were simultaneously increased by the supplementation of karaya saponin, R. capsulatus, and the combination of karaya saponin and R. capsulatus (P < .05). The supplementation of karaya saponin, R. capsulatus, and the combination of karaya saponin and R. capsulatus suppressed the incorporation of (14)C from 1-(14)C-palmitic acid into the fractions of total lipids, phospholipids, triacylglycerol, and cholesterol in the liver in vitro (P < .05). These findings suggest that the hypocholesterolemic effects of karaya saponin and R. capsulatus are caused by the suppression of the cholesterol synthesis and the promotion of cholesterol catabolism in the liver.

Karaya root saponin exerts a hypocholesterolemic response in rats fed a high-cholesterol diet

Different sources of saponins are known to have hypocholesterolemic activity with varying degrees of efficacy. We hypothesize that karaya root saponin would efficiently reduce cholesterol. The aim of this study is to examine the comparative hypocholesterolemic effect of karaya root saponin in rats fed a high-cholesterol diet. Sixty male Wister-Imamichi rats were divided into 5 groups of 12 rats each constituting of the following: control group, soybean saponin-supplemented group, karaya root saponin-supplemented group, quillaja saponin-supplemented group, and tea saponin-supplemented group. Compared with the control diet, both the karaya root- and quillaja saponin-supplemented diets significantly reduced (P < .05) serum cholesterol and atherogenic index. Karaya root saponin significantly increased the serum high-density lipoprotein cholesterol, high-density lipoprotein cholesterol/cholesterol ratio, and fecal cholesterol concentrations (P < .05). The triacylglycerol concentration was significantly reduced only in the quillaja saponin-supplemented rats (P < .05). All the tea, soybean, karaya root, and quillaja saponins significantly reduced low-density lipoprotein cholesterol, and the greatest reduction was observed with karaya root saponin. Highest fecal bile acid concentration was found with quillaja saponin, whereas highest liver bile acid concentration was observed with karaya root saponin-supplemented rats (P < .05). These results collectively suggest that karaya root saponin can efficiently reduce serum cholesterol concentration in rats.

Effect of dietary Rhodobacter capsulatus on cholesterol concentration and fatty acid composition in broiler meat

The study was designed to investigate the effects of dietary Rhodobacter capsulatus on cholesterol concentration and fatty acid composition in broiler meat. A total of 45 two-week-old male broiler chicks were randomly assigned into 3 treatment groups and fed ad libitum diets supplemented with 0 (control), 0.02, and 0.04% R. capsulatus for a 6-wk feeding period. The results of this study revealed that the supplementation of 0.04% R. capsulatus in diet reduced (P < 0.05) cholesterol and triglyceride concentrations in broiler meat. The concentrations (expressed as a percentage of total fatty acids) of oleic acid (18:1), linoleic acid (18:2), and linolenic (18:3) acid in thigh muscle and breast muscle were higher (P < 0.05) in the broilers fed the 0.04% R. capsulatus supplemented diet than in the broilers fed the control diet. The ratio of unsaturated fatty acids to saturated fatty acids was greater (P < 0.05) in both muscles of broilers fed the 0.04% R. capsulatus supplemented diet than the control diet. In addition, the concentrations of serum cholesterol and triglyceride, and hepatic cholesterol and triglyceride were also reduced (P < 0.05) by dietary R. capsulatus. Compared with the control diet, the 0.04% R. capsulatus supplemented diet reduced (P < 0.05) the ratio of low-density lipoprotein-cholesterol to high-density lipoprotein-cholesterol. Moreover, the supplementation of R. capsulatus in broiler diets did not show any adverse effect on production performance. Therefore, these results conclude that the application of R. capsulatus into diet may be feasible to reduce cholesterol concentration and improve the ratio of unsaturated fatty acids to saturated fatty acids in broiler meat.