Search

In this study, we investigated the effects of dietary supplementation with Bacillus subtilis(QST713) on the performance and intestinal health of yellow feather broilers under Coccidia and Clostridium perfringens (CP)challenge or CPalone. One-day-old yellow-feathered broiler roosters (n = 600) were randomly assigned to 5 groups (6 replicates with 20 roosters per replicate): the Con blank group, the CIC.pgroup (d24 Coccidia+d28-30 of CPchallenge), the CIC.p+ BS group (CIC.p+100 mg/kg B. subtilis), the C.pgroup (d 28–34 of CPchallenge), and the C.p+BS group (C.p+100 mg/kg B. subtilis). The experiment lasted 80 d. The birds were evaluated for parameters such as average daily gain (ADG), average daily feed intake (ADFI), feed efficiency (F/G), intestinal lesion score, villus histomorphometry, intestinal tight junctions, inflammatory factors, and cecal microorganisms. The results revealed that 1) C.p.increased the F/G of broilers from 22 to 42 d (P< 0.05), whereas CIC.p.significantly decreased the 42 d and 80 d body weights (BW) and 22–42 d and 1–80 d ADG (P< 0.05) and significantly increased the 22 to 42 d and 1 to 80 d F/G (P< 0.05). The number of intestinal lesions significantly increased at 35 d and 42 d (P< 0.05). CIC.psignificantly decreased the jejunum and ileum villus height (VH) and the ileum villus height/crypt depth (P< 0.05) at 35 d. The challenge significantly upregulated the expression of Claudin-1 and IL-4 mRNAs in the jejunum at 35 d and significantly downregulated the expression of IL-10 mRNA in the ileum at 35 d (P< 0.05); the number of unique OTUs in the challenge group decreased significantly after challenge treatment, and the relative abundances of Romboutsiaat 35 d and Cladomycesand Lactobacillusat 42 d decreased significantly (P< 0.05). 2) Compared with the challenge groups, the addition of BS decreased the F/G of broilers from 22 to 42 d. Compared with the CIC group, the addition of BS significantly increased the F/G of broilers from 22 to 42 d. Compared with that in the CIC.pgroup, the addition of BS significantly increased the VH in the jejunum and ileum at 35 d (P< 0.05). Compared with the challenge groups, the BS groups presented significantly lower mRNA expression levels of Claudin-1 (P< 0.05) in the jejunum at 35 d. The Shannon and Chao indices suggested that BS increased the alpha diversity of cecum microorganisms in broilers. Dietary supplementation with B. subtiliscan alleviate the damage to intestinal morphology and intestinal barrier function, as well as the altered cecal flora structure in broilers caused by Coccidiaand C. perfringensinfections.

This study was conducted to evaluate the effects of ageing corn levels (stored for 4 years) with or without the supplementation of tea polyphenols (TPP) on the performance, egg quality and antioxidant status of laying hens. A total of 288 Lohmann commercial laying hens (63-week-old) were used under a 2 × 4 factorial arrangement with 4 levels of dietary ageing corn (0%, 25%, 50%, or 100%) and 2 levels of TPP (0 and 600 mg/kg) for 8 wk. Dietary ageing corn linearly decreased (P < 0.05) the egg production, serum total antioxidant capacity (T-AOC), liver glutathione peroxidase (GSH-Px) of laying hens, yolk index, yolk colour, 1,1-diphenyl-2-picrylhydrazyl (DPPH) value and the reducing power value of egg yolk, but it linearly increased (P < 0.05) the feed conversion rate, ovary malondialdehyde (MDA) content of laying hens, and the protein carbonyl content of egg yolk. Tea polyphenol supplementation increased (P < 0.05) the serum T-AOC, serum superoxide dismutase (SOD), liver SOD, liver GSH-Px, ovary SOD, GSH-Px, the expression of antioxidant-related genes of laying hens, albumen height, Haugh unit, DPPH value and the majority free amino acids of egg yolk, but it decreased (P < 0.05) the serum MDA content of laying hens, MDA and protein carbonyl of egg yolk. In conclusion, the ageing corn significantly reduced the performance, egg quality, antioxidant status and egg antioxidant capacity of laying hens, while TPP supplementation partially counteracted the adverse effects, especially antioxidant status and egg antioxidant capacity of laying hens.

The difference in microbiota was examined for breeders with different egg-laying rates, and the impact of dietary Enterococcus faecium(EF) was also determined in the present study. A total of 256 Arbor Acres broiler breeders (48-wk-old) were used in a 2 × 2 factorial design, which encompassed 2 egg-laying rate levels [average (average egg laying: AP, 80.45 ± 0.91%) and low (lower egg laying: LP, 70.61 ± 1.16%)] and 2 different dietary groups [control (no additive), 6 × 108 cfu/kg EF]. The results showed that the AP breeders presented a lower egg weight, feed conversion ratio, abdominal fat rate, and serum leptin level (P(laying) ≤ 0.05) as well as a higher egg-laying rate (P(laying) < 0.01) than the LP breeders. Dietary supplementation with EF improved the egg weight (P(EF) = 0.03) and had a higher concentration of follicle-stimulating hormone (FSH) in the serum (P(EF) = 0.04). The relative expression of Caspase 9, Bax, AMHR, BMP15, and GATA4 in the ovary of AP breeders was lower, whereas the FSHR and BMPR1B expression was higher than that measured in LP breeders (P(laying) ≤ 0.05). LP increased the abundance of Bacteroidetes(phylum), Firmicutes(phylum), Bacteroidia(class), Clostridia(class), Bacteroidales(order), Clostridiales(order), and Lachnospiraceae(family), whereas the AP promoted the enrichment of Proteobacteria(phylum) and Gammaproteobacteria(class) (P(laying) < 0.05). The genera Bacillus, Rhodanobacter,and Streptomyceswere positively correlated with the egg-laying rate and BMPR1B expression (P < 0.05) but negatively correlated with the abdominal fat rate (P < 0.05) and Caspase 9 (P < 0.05). These findings indicate that the low reproductive performance breeders had lower microbiota diversity and higher Firmicutes, which triggers the energy storage that led to higher fat deposition. Besides, increases in the abdominal fat rate, leptin level, and apoptosis (Caspase 9, Bax) and reproduction-related gene (BMP15, AMHR, BMPR1B, and GATA4) expression would possibly be the potential mechanisms under which breeders have different reproductive performance. Dietary EF increased the egg weight and serum FSH level and decreased the Bacteroidetes(phylum) in low reproductive breeders.

This study was conducted to determine the effects of supplemental dietary benzoic acid on production performance, egg quality, intestinal morphology, and intestinal microbiota of laying hens. A total of seven hundred twenty 45-wk-old Lohman pink-shell laying hens were randomly allocated to 3 dietary treatments: control (CON), diet supplemented with 1,000 mg/kg benzoic acid (BA1), and 2,000 mg/kg benzoic acid (BA2). Each treatment included 10 replicates of 24 hens; laying hens were monitored for 16 wk. Overall, the results indicate that benzoic acid supplementation had no effect on laying rate, feed intake, feed conversion ratio, and breaking rate; however, a decrease in egg weight (P < 0.01) was observed in the BA2 group. Albumen height and Haugh unit (HU) were also linearly increased in the BA1 and BA2 groups (linear effect, P < 0.05). An increase in duodenum villus height (V) (quadratic effect, P = 0.041) and crypt depth (C) (linear effect, P = 0.012) was observed in the BA2 group, whereas an increased jejunum C and decreased V/C (quadratic effect, P < 0.05) in the BA1 group. Moreover, an increase in ileum V and C (quadratic effect, P < 0.05) was observed in the BA1 group. Microbial richness and diversity were reduced in the BA2 group (P < 0.01). An increase in the abundance of Clostridia(class), Clostridiales(order), Ruminococcaceae(family), and Lachnospiraceae(family) was noted in the BA1 group, whereas an enrichment of Bacteroides caecicola(species) was observed in the BA2 group. The HU positively correlated with genus Sphaerochaetaand Enorma(r = 0.56, 0.56; P < 0.05) but negatively correlated with Romboutsia, Subdoligranulum, Helicobacter, and Mucispirillum(r = −0.58, −0.49, −0.48; −0.70; P < 0.05). In conclusion, dietary supplementation with benzoic acid had no effect on production performance, but it significantly improved egg quality. In addition, 1,000 mg/kg benzoic acid positively modulated intestinal health by improving intestinal morphology and enriching microbial composition.

Leg problems often result from the rapid weight gain and poor bone quality in modern ducks, leading to a high risk of fractures and continuous pain. We hypothesized that improving bone quality in combination with delaying weight gain via a low nutrient density (LND) diet probably reverses these skeletal abnormalities. Studies indicated that 25-hydroxycholecalciferol (25-OH-D3), a vitamin D3metabolite, is effective in treating bone-related disorders. Therefore, Exp. 1 evaluated the effects of 25-OH-D3on tibial mass of meat ducks. Male meat ducklings were fed a standard nutrient density diet (containing a regular vitamin regimen) without or with 25-OH-D3at 0.069 mg/kg for 35 d. The results showed that 25-OH-D3supplementation improved the mineral content, microarchitecture and mechanical properties of tibias, and this companied by a decreased serum bone resorption marker and a concomitant decrement in osteoclast-specific marker genes expression. Subsequently, Exp. 2 was conducted to examine the impacts of 25-OH-D3incorporating an LND diet on tibial quality of ducks under 2 different vitamin regimens (regular and high). Ducklings were allocated to a 2 × 2 factorial arrangement with 2 kinds of vitamin premixes and without or with 25-OH-D3at 0.069 mg/kg in LND diets. The high premix had higher levels of all vitamins except biotin than the regular premix. The results demonstrated that high vitamin diets exhibited more significant effects than regular vitamin diets on inhibiting bone turnover and increasing minerals deposition. Tibial mineral content, microarchitecture, and strength of birds under the regular vitamin regimen were increased by 25-OH-D3supplementation; However, these positive effects were not observed in ducks under the high vitamin regimen. To conclude, 25-OH-D3supplementation improves tibial mass by suppressing osteoclast-mediated bone resorption in meat ducks, and this positive impact only was observed in regular but not high vitamin regimen when birds fed an LND diet.

This study was conducted to determine the effects of 25-hydroxycholecalciferol (25-OH-D3) on performance, egg quality, tibia quality, and serum hormones concentration in laying hens reared under high stocking density. A total of 800 45-week-old Lohmann laying hens were randomly allotted into a 2 × 2 factorial design with 2 levels of dietary 25-OH-D3levels (0 and 69 μg/kg) and 2 rates of stocking densities [506 (low density) and 338 (high density) cm2/hen]. Laying hens were monitored for 16 wk. High stocking density decreased laying rate, egg weight, and feed intake compared with low stocking density (P< 0.01) during 1 to 8 wk and 1 to 16 wk. Overall, high stocking density increased eggshell lightness value and decreased shell redness and yellowness value, strength, thickness, and relative weight compared with low stocking density (P < 0.05). Dietary supplementation with 25-OH-D3reduced the value of the eggshell lightness and increased its yellowness and eggshells weight (P≤ 0.05). The increase in eggshell thickness was more pronounced when 25-OH-D3was supplemented to layers under high stocking density (interaction, P< 0.05). Layers under high stocking density had lower ash content and calcium content in the tibia than layers under low stocking density (P= 0.04); dietary 25-OH-D3increased tibia strength compared with no addition (P= 0.05). Layers under high stocking density had higher serum concentrations of 25-OH-D3, corticosterone (CORT), lipopolysaccharide (LPS), and osteocalcin (OC; P< 0.05), lower content of parathyroid hormone (PTH) compared with layers under low stocking density (P< 0.01). Dietary 25-OH-D3increased serum concentration of 25-OH-D3, carbonic anhydrase (CA), and calcitonin (CT) (P< 0.01) and reduced corticosterone, lipopolysaccharide and osteocalcin concentration (P≤ 0.05). The increase effect in PTH was more pronounced when 25-OH-D3was supplemented to layers under high stocking density (interaction, P= 0.05). Overall, the results gathered in this study indicate that high stocking density result in reducing production performance, shell color and quality, and tibia health, whereas dietary 25-OH-D3was able to maintain tibia health and to mitigate the negative impact of high stocking density on productive performance.

The tea polyphenol (TP) can improve the egg albumen quality in laying hens; however, our understanding of the molecular mechanisms and proteomic changes in the egg albumen remains limited. A total of 720 layers (35-wk-old) were allocated into 5 treatments with TP and were added at 0 (control), 200 (TP200), 400 (TP400), 600 (TP600), and 800 (TP800) mg/kg. It showed that 400 mg/kg TP increases albumen height and Haugh unit (quadratic effect, P< 0.01), while 400 mg/kg TP decreases gel strength, hardness, gumminess, and chewiness value in a quadratic manner (P= 0.01). Eggs from TP400-fed layers had highest reducing power and oxygen radical absorbance capacity, and lowest albumen malondialdehyde content (quadratic effect, P< 0.05). Through Tandem Mass Tag-based quantitative proteomics analysis, 258 proteins were identified and 31 differentially accumulated proteins in egg white affected by 400 mg/kg TP compared to control group, with 19 proteins upregulated and 12 proteins downregulated. A total of 11 binding proteins (A0A1D5PZE3, F1NTQ2, Q7SX63, F1NRV5, P24802, A0A1L1RM02, E1BTX1, A0A1L1RMF4, A0A1D5P1N3, A0A1L1RML6, A0A1L1RQF3), 9 immune response proteins (P10184, R4GI90, P01875, Q6IV20, Q64EU6, P02701, P08110, P0CB50, A0A1D5PQ63), and 3 cell redox homeostasis proteins (P0CB50, P20136, Q8JG64) were changed in albumen of laying hens fed TP400. The differentially expressed proteins mainly involved in pyruvate metabolism, cysteine and methionine metabolism, glutathione metabolism, glycolysis, and protein processing in endoplasmic reticulum pathway. The result gathered in this study suggested that the improving mechanism of TP on albumen quality may act through regulating binding mediation, immune function, and antioxidant activity-related proteins.

This study investigated the effects of xylo-oligosaccharide supplementation on the production performance, intestinal morphology, cecal short-chain fatty acid levels, and gut microbiota of laying hens. A total of 800 Lohmann pink layers, each 48 weeks old, were randomly divided into 5 dietary treatment groups, namely XOS at 0 (CON), 100 (XOS1), 200 (XOS2), 300 (XOS3) and 400 (X0S4) mg/kg. The experimental period was 24 weeks. The results revealed that the egg production rate and the number of eggs laid by each layer between 1 to 12 weeks increased as the XOS concentration increased (Plinear< 0.05). The sand-shell egg percentage decreased significantly from 1 to 12 weeks in the XOS1, XOS2, and XOS3 groups (PANOVA< 0.05). Compared with the CON group, the four XOS dosage groups presented significant increases in the villus height and the ratio of villus height to crypt depth in the jejunum (PANOVA< 0.05), whereas a linear decrease in jejunal crypt depth (Plinear< 0.05) was noted. In addition, XOS supplementation significantly increased the concentrations of butyric acid and isovaleric acid in the caeca (PANOVA< 0.05). High-throughput sequencing analysis of bacterial 16S rRNA revealed that dietary XOS supplementation influenced the cecal microbiota. The alpha diversity analysis indicated that the richness of cecal bacteria was greater in the laying hens fed XOS. The modulation of the cecal microbiota composition upon the addition of XOS was characterized by an increased abundance of Firmicutesand Bifidobacteriaceae, and decreased abundance of Bacteroidetes. At the genus level, dietary XOS supplementation resulted in decreases in the abundances of Bacteroidesand Rikenellaceae_RC9_gut_group and an increase in the abundance of Lactobacillus. In conclusion, dietary XOS supplementation improved the production performance of laying hens by increasing the production of short-chain fatty acids and improving their intestinal morphology, which was achieved mainly through changes in the composition of the intestinal microbiota. The recommended level of XOS in the diet of laying hens is 200 mg/kg.

Studies have reported that theabrownin can moderate the lipid metabolism and intestinal microbiota, thereby affecting the health of humans and model animals, however the research on laying hens is scarce. The present study aimed to investigate the effects of dietary theabrownin supplementation on lipid metabolism, microbial composition and ovarian function in laying hens. A total of 80 laying hens (25 weeks of age) were fed with normal diet (CON) and normal diet +100 mg/kg theabrownin (PT group) for 12 weeks. The results showed that the addition of theabrownin enhanced villus height of duodenum and decreased crypt depth of jejunum (P< 0.05). At the same time, compared with CON, the concentration of IL-6 and the mRNA expression of IL-1βand IL-6were decreased significantly in PT group (P< 0.05). Dietary theabrownin reduced the concentration of total cholesterol and glycerol, while decreased lipid droplet optical density in liver (P< 0.05). Compared with CON group, the mRNA expression of PPARγ, HMG-CoAS, ACCwere down-regulated and the mRNA expression of CYP8B1was up-regulated in PT group (P< 0.05). The ACE, Chao1 and Observed_species indexes in cecum microbiota were increased by PT group intervention (P< 0.05). Dietary PT supplementation enhanced the relative abundance of Firmicutes(phylum), Lactobacillus(genus) and the Firmicutesto Bacteroidetesratio, and reduced the relative abundance of Bacteroidetes(phylum) in cecum (P< 0.05). The organic acids and its derivatives were up-regulated by theabrownin intervention in serum metabolites (P< 0.05). Dietary theabrownin supplementation resulted in higher mRNA expression of Bcl-2and SIRT1in ovary and increased the concentration of estradiol in serum (P< 0.05). These discovering indicated that dietary theabrownin supplementation enhanced the intestinal function and influenced serum metabolism by improving intestinal morphology, microbiota community structure and reducing the concentration and expression of inflammatory cytokines in intestine. Dietary theabrownin reduced hepatic lipid deposition and it also decreased the cell apoptosis rate to improve ovarian function and egg weight which were associated with the SIRT1 pathway.

In this study, we aimed to investigate the effect of Scutellaria baicalensisand Lonicerae Flos(SL) extract on the growth performance and intestinal health of yellow-feather broilers following a Clostridium perfringenschallenge. In total, 600 one-day-old yellow-feather broilers were divided into five treatments (6 replicate pens of 20 birds per treatment), including a control (Con) group fed a basal diet and the infected group (iCon) fed a basal diet and infected with Clostridium perfringens, the other three groups receiving different doses of SL (150 mg/kg, 300 mg/kg, and 450 mg/kg) and infected with Clostridium perfringens. The total experimental period was 80 days. When the birds were 24 days old, a subclinical necrotizing enteritis model was induced by orally inoculating the birds with 11,000 oocysts of mixed Eimeria species on day 24, followed by C. perfringens(108CFU/mL) from days 28 to 30. The birds were evaluated for parameters such as average weight gain (AWG), average daily feed intake (ADFI), mortality, feed conversion ration (FCR), intestinal lesion score, intestinal C. perfringenscounts, and villus histomorphometry. Results indicated that C. perfringensinfection led to reduced AWG and the levels of tight junction proteins, increased the FCR, ileum E. coliload, and intestinal permeability, causing damage to the intestinal mucosal barrier (P < 0.05). Compared with the infected group, supplementing 300 mg/kg of SL significantly increased AWG at 43–80 days, the ratio of villus height to crypt depth in the jejunum and ileum at 35 days, and the activity of superoxide dismutase (SOD) in serum. It also significantly reduced the FCR at 22–42 days, intestinal lesion score, and the amount of C. perfringensin the ileum (P < 0.05). Additionally, compared with the infected group, the addition of 300 mg/kg SL significantly increased mRNA levels of claudin-2, claudin-3, mucin-2, and toll-like receptor 2 (TLR-2) in the ileum of infected birds at 35 days of age. In conclusion, supplementation with SL extract could effectively mitigate the negative effects of C. perfringenschallenge by improving intestinal barrier function and histomorphology, positively influencing the growth performance of challenged birds.

An experiment was conducted to determine the effects of betaine on growth performance and intestinal health in rabbits fed diets with different levels of digestible energy. During a 36-d experiment, a total of 144 healthy 35-d-old weaned New Zealand white rabbits with a similar initial body weight (771.05 ± 41.79 g) were randomly distributed to a 2 × 3 factorial arrangement. Experimental treatments consisted of two levels of digestible energy (normal: 10.20 and low: 9.60 MJ/kg) and three levels of betaine (0, 500, and 1,000 mg/kg). Results indicated that rabbits fed the diet with low digestible energy (LDE) had reduced body gain/feed intake on days 1 to 14 and 1 to 36 (P< 0.05), increased the apparent total tract digestibility (ATTD) of neutral detergent fiber, acid detergent fiber (ADF), and n-free extract, and decreased the ATTD of gross energy (GE), crude fiber, and organic matter (OM; P< 0.05). The LDE diet upregulated the gene abundance levels of duodenum junctional adhesion molecule-3(JAM-3) and downregulated the ileum toll-like receptor 4, myeloid differentiation factor 88, and interleukin-6(IL-6; P< 0.05). Activities of amylase, lipase, trypsin, and the immunoglobulin M content in the jejunum were decreased in the LDE treatment group (P< 0.05). Dietary betaine supplementation increased the ATTD of GE, dry matter (DM), ADF, and n-free extract by LDE (P< 0.05). The villus height, crypt depth, and goblet cell numbers were decreased, and the villus–crypt ratio was increased in the duodenum (P< 0.05). The gene abundance levels of duodenum IL-2were downregulated, and the duodenum JAM-2and JAM-3were upregulated (P< 0.05). Furthermore, the addition of betaine to the LDE diet increased the ATTD of GE, DM, and OM in rabbits (P< 0.05). Gene abundance levels of ileum IL-6and duodenum JAM-3were upregulated (P< 0.05). In summary, LDE diets can reduce the activity of intestinal digestive enzymes and decrease the ATTD of nutrients. However, the addition of betaine to LDE diets improved the intestinal barrier structure and nutrient ATTD in rabbits, with better results when betaine was added at an additive level of 500 mg/kg.Dietary betaine can alleviate the adverse effects of low dietary energy on rabbit production.Insufficient dietary energy can cause many negative effects on animal production and cause intestinal diseases, which are one of the main causes of morbidity and mortality in rabbits. Results of some experiments demonstrated that betaine has various physiological functions such as improving energy utilization and intestinal health. Therefore, the aim of this study was to evaluate the effects of betaine supplementation on growth performance, intestinal function, and health in rabbits fed diets with different levels of digestible energy. The results showed that the addition of betaine to a low-digestible energy diet improved the gut barrier structure and nutrient digestibility in rabbits.

To evaluate the toxic effects of mycotoxin-contaminated corn (MC) on the breeders and their progeny chicks, a total of 480 fifty-wk-old Cobb broiler breeder hens were fed the following dies: 1) a corn-soybean meal diet (Control; containing 70.35% corn), 2) MC substituting for 50% of corn in Control (LM), 3) LM diet plus 2 g/kg 1 mycotoxin sequestrant, Toxy-Nil Plus (TNP) (LMT2.0), 4) MC substituting for 100% of corn in Control (HM), 5) HM diet plus 2 g/kg TN (HMT2.0), and 6) HM diet plus 2.5 g/kg TNP (HMT2.5). The MC contained 69.25 μg aflatoxin B1 (AFB1)/kg, 4,875 μg deoxynivalenol (DON)/kg, and 2,262 μg zearalenone (ZEN)/kg. At wk 4 after MC inclusion, all eggs laid were used for hatch, and all progeny chicks were fed the same mycotoxin-untreated diet for 14 d. Dietary MC inclusion decreased the hatchability of set eggs and increased embryo mortality during d 18 to 21.5. The TNP addition increased these aforementioned indices in MC-included diets. Maternal HM treatment decreased the BW of progeny chicks at age of 14 d and BWG of progeny chicks during d 1 to 14, whereas maternal LM treatment did not affect these indices. In parallel, maternal HM treatment decreased the concentrations of serum IgA, IgG, and lysozyme in the progeny chicks on d 14, but maternal LM treatment did not affect these indices. Overall, maternal dietary TNP treatments increased the growth of progeny chicks and had a trend to increase the concentrations of serum IgA and IgG on d 14 compared to maternal MC treatments. It was concluded that the feeding of relative high ratio of corn contaminated with low level of AFB1, DON, and ZEN negatively affected the reproductive performance of breeders and the growth performance of their progeny chicks, and TNP addition alleviated these toxic effects.

This experiment was conducted to investigate the effect of theabrownins (TB) on production performance, egg quality, and ovarian function of laying hens at different ages. A total of 240 Lohmann laying hens were assigned in a 2 × 2 factorial design, which encompassed 2 layers ages (47-wk-old and 67-wk-old) and 2 dietary levels of TB (0 and 100 mg/kg) for 12 wk. Results showed that older layers had lower laying rate, egg mass, and higher feed-to-egg ratio (F/E), egg weight and unqualified egg rate than the younger layers (P(AGE)< 0.01) during all the experimental period. The effect of TB was found to increase egg laying rate and feed efficiency during 5 to 8 wk, 9 to 12 wk and the overall phases and decreased unqualified egg rate during 1 to 4 wk and the overall phases (P(TB)≤ 0.05). The eggshell quality (strength, thickness), albumen quality (albumen height and Haugh unit) of eggs from older layers were decreased during overall phases (P(AGE)≤ 0.05). TB increased eggshell strength during all phases and enhanced eggshell thickness at the end of wk 4 and 8 and increased albumen height and Haugh unit at the end of wk 8 and 12 of older layers (P(Interaction)≤ 0.05). In addition, TB also increased egg quality of older layers after 14 d storage. A decrease in the serum concentration of progesterone, melatonin, follicle stimulating hormone, estradiol was observed in the older compared to the younger ones (P(AGE)< 0.05), while the increase in serum concentration of progesterone, melatonin, anti-Müllerian hormone (AMH) were more emphasized when older hens received TB supplemented diet (P(Interaction)< 0.05). The older layer demonstrated lower the concentration of glutathione (GSH) (P(AGE)< 0.05). And the activity of glutathione-s-transferase (GST) was significantly decreased in layers under 67-wk-old (P(AGE)<0.05). The increase in concentration of GSH and the decrease in concentration of malondialdehyde (MDA) were more pronounced when TB were supplemented in 67-wk-old layers (P(Interaction)≤ 0.05). Layers at 67-wk-old had lower mRNA expression of Heme oxygenase 1 (HO-1) (P(AGE)< 0.01) in ovary.Dietary TB supplementation upregulated mRNA gene expression of HO-1, Nuclear factor E2 related factor 2 (Nrf2), Quinone oxidoreductase 1 (NQO1) (P(TB)< 0.01). Dietary TB upregulated mRNA expression of ovarian reproductive hormone receptor (estrogen receptor 1 [ESR1] and steroidogenic acute regulatory protein 1 [StAR1]]; P(TB)< 0.01). The results suggest feeding TB (100 mg/kg) could improve the egg production rate, egg quality, and antioxidant capacity of the ovary. Moreover, the effect of TB was more pronounced in older layers (64-wk-old vs. 47-wk-old).

The objective of this study was to investigate the effect of reduced levels of Cu, Zn, Mn in combination from organic mineral source on eggshell quality and mineral retention in hens. After feeding the basal diet (8.82 mg/kg Cu, 24.94 mg/kg Zn, and 16.38 mg/kg Mn) without Cu, Zn, and Mn addition for 4 weeks, hens (39-week-old) were assigned to 5 treatments according to the equal body weight and egg production for 12-week experimental trial. The 5 treatments included the basal diet without Cu, Zn, and Mn (NCON), and NCON added with 16-80-60 mg/kg Cu-Zn-Mn from sulfates (ITM100%), or 4-20-15, 8-40-30 or 16-80-60 mg/kg Cu-Zn-Mn from 2-hydroxy-4-(methylthio)butanoic acid (HMTBA) mineral chelates (OTM25%, OTM50% or OTM100%). Supplementation of Cu, Zn, and Mn had no significant influences on the performance of hens. After 12 weeks feeding, eggshell breaking strength (EBS) decreased in the following order: OTM25% and ITM100% > OTM50% > NCON and OTM100%. The eggshell weight and thickness in OTM25% were greater than that in NCON, while not differing from that in ITM100%. The EBS and eggshell weight linearly decreased with increasing level of OTM. After 12 weeks feeding, supplementation of Cu, Zn, and Mn increased the concentrations of liver Zn, tibia Zn and Mn, and Zn and Mn retention in eggs as compared with NCON. No significant difference was observed in the concentrations of Cu, Zn, and Mn in liver and plasma, and Zn and Mn in eggs between any OTM treatment and ITM100% groups. Addition of OTM at increasing level had quadratic effect on tibia Cu, Zn, Mn concentrations, with the greater retention of Cu, Zn, and Mn in OTM50%. In conclusion, the OTM25% from HMT BA mineral chelates can substitute for ITM100% evaluated by the eggshell quality in the diet of laying hens.

The effect of 25-hydroxyvitamin D (25OHD) on the immune response of laying hens is not well elucidated. This study investigated the effects of 25OHD on egg production, egg quality, immune response, and intestinal health of laying hens challenged with Escherichia colilipopolysaccharide (LPS). One hundred and sixty laying hens at 45 wk of age were randomly divided into 4 dietary treatments with 10 replicates of 4 birds. Hens were fed the corn-soybean based diets contained either 0 or 80 µg/kg 25OHD for 8 wks. At wk of 53 wk, birds of each dietary treatment were injected into the abdomen with 1.5 mg/kg body weight of either LPS or saline a day at 24-h intervals for continuous 7 d. LPS injection significantly decreased (PLPS< 0.05) egg laying rate, feed intake and feed efficiency; while the supplementation of 25OHD increased (PInteraction< 0.05) egg laying rate, feed efficiency and decreased (PInteraction< 0.05) the broken egg rate in layers under LPS injection. LPS challenge decreased (PLPS< 0.05) eggshell strength, eggshell thickness, albumen height and Haugh unit, while dietary 25OHD supplementation increased eggshell strength and eggshell thickness (P25OHD< 0.05). The serum proinflammatory factors [tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6)], endotoxin and diamine oxidase (DAO) levels were higher in layers under LPS challenge (PLPS< 0.05); whereas the dietary addition of 25OHD were shown to decrease (P25OHD< 0.05) serum IL-1β and IL-6 concentration irrespective of LPS challenge and led to a higher serum 25OHD level and a reduction in endotoxin concentration in layers under LPS challenge (PInteraction< 0.05). The layers under LPS challenge had higher crypt depth and lower villus height/crypt depth (V/C) ratio in duodenum and jejunum (PLPS< 0.05), while feeding 25OHD were shown to have decreasing effect on crypt depth and increasing effect V/C ratio in layers under LPS challenge (PInteraction< 0.05). Layers under LPS challenge had lower mRNA expression of intestinal barrier associated proteins (claudin-1 and mucin-1) (PLPS< 0.05), while the addition of 25OHD up-regulated claudin-1 and mucin-1 expression (Pinteraction< 0.05). Lower antioxidant enzymes activities, including superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), glutathione peroxidase (GPx) and higher malondialdehyde (MDA) content in jejunum were found in layers challenged with LPS (P25OHD< 0.05). The effect of 25OHD reversed the effect of LPS on SOD, T-AOC, and MDA content (PInteraction< 0.05). These results suggest that supplementing 80 µg/kg 25OHD in diets may elevate laying performance and egg quality through the improvement of intestinal barrier function, antioxidant capacity, and decreased the proinflammatory cytokines levels in laying hens with Escherichia coliLPS challenge.

In the present study, we aimed to elucidate the effects of stevia extract on production performance, serum immune indexes, intestinal structure, and cecum microbial structure. We randomly divided 800 46-week-old Roman hens into 5 groups, with eight replicates in each group and 20 chickens in each replicate. The control group was fed a basal diet, whereas the four experimental groups were fed 50, 100, 200, and 400 mg/kg stevia extracts. The study period was 24 weeks. The addition of different concentrations of the stevia extract to the diet resulted in significant secondary changes in the egg production rate at 1–12 weeks (P< 0.05). Furthermore, the addition of 50 and 100 mg/kg stevia extract to the diet significantly increased serum IgM and IgG levels in laying hens (P< 0.05) but linearly decreased serum IL-1β levels (P< 0.05). Serum T-SOD activity linearly increased (P = 0.057); however, serum biochemical indexes showed no significant differences. Stevia extract tended to increase the ratio of the duodenal villi height to the depth of the crypt (P = 0.067), with no obvious lesions in the duodenum, jejunum, and ileum. In addition, stevia extract increased the relative abundance of species at the phylum level, with the abundance of Bacteroidesand Firmicutesexhibiting significant secondary changes (P< 0.05). The ACE and Chao1 indexes suggested that stevia extract addition significantly increased the alpha diversity of cecum microorganisms in laying hens. Furthermore, NMDS analysis based on operational taxonomic units revealed that stevia extract addition increased the beta diversity of cecum microorganisms in laying hens. Adding a certain amount of stevia extract to feed can improve the production performance, immune ability, and intestinal health of laying hens to some extent, and we recommend an effective level of 200mg/kg of stevia extract for laying hen diets.

The underlying mechanism between the gut microbiota and reproductive function is not yet well-known. This study was conducted to investigate the effect of the administration of fecal microbiota transplantation (FMT) from highly laying rate donors on the cecal microbiota, intestinal health and ovarian function in broiler breeders. A total of 60 broiler breeders (53 wk of age) were selected by their laying rate [high (HP, 90.67 ± 0.69%; n = 10) and low (LP, 70.23 ± 0.87%; n = 20)]. The LP breeders were then be transplanted with fecal microbiota from HP hens (FMTHP; n = 10) or the same dosage of PBS (FMTCON; n = 10) for 28 d. The results revealed that FMT from HP donors increased egg-laying rate and serum hormone levels [17β-estradiol (E2), anti-Müller hormone], also decreased proinflammatory cytokine levels (interleukin-6, interleukin-8, tumor necrosis factor-α) of LP breeders (P< 0.05). The FMTHP group breeders had higher villus height, villus height/crypt depth ratio, and upregulated mRNA expression of jejunum barrier-related gene (ZO-2and mucin-2) and estrogen, follicle-stimulating hormone (FSH) and anti-Müller hormone (AMH) receptor genes (ESR1, ESR2, FSHR, AMHR) (P< 0.05) than FMTCON group. FMT from HP donors led to higher mRNA expression of Bcl2and sirtuin1 (SIRT1), while it downregulated the proapoptotic genes (Bax, caspase-3, caspase-8, and caspase-9) mRNA expressions in ovary compared with the FMTCON breeders (P< 0.05), and this pattern was also observed in HP donors. Also, HP breeder had higher observed_species and alpha-diversity indexes (Chao1 and ACE) than FMTCON group, while FMTHP can increase observed_species and alpha-diversity indexes (Chao1 and ACE) than FMTCON group (P< 0.05). The bacteria enrichment of Firmicutes (phylum), Bacteroidetes (phylum), Lactobacillus(genus), Enterococcus(genus), and Bacteroides(genus) were increased by FMTHP treatment. The genera Butyricicoccus, Enterococcus, and Lactobacilluswere positively correlated with egg-laying rate. Therefore, cecal microbiomes of breeders with high egg-laying performance have more diverse activities, which may be related to the metabolism and health of the host; and FMT from high-yield donors can increase the hormone secretion, intestinal health, and ovarian function to improve egg-laying performance and the SIRT1-related apoptosis and cytokine signaling pathway were involved in this process.

The objective of this study was to investigate whether dietary supplementation with benzoic acid, Enterococcus faecium, and essential oil complex (BEC) could help laying hens recover from coccidia and Clostridium perfringenstype A challenge. A total of 60 (35-wk-old) Lohmann laying hens were randomly assigned to 3 experimental groups (10 replicates with 2 hens per replicate): (I) control group (CON), (II) challenge group (CC), and (III) BEC group (2000mg/kg BEC). The total experimental period was 8 wk. The results shown that the challenge layers had lower egg laying rate and average daily feed intake (ADFI) (P< 0.05), and addition of BEC after challenge increased egg laying rate (P< 0.05). The content of propionic acid (PA) and butyric acid (BA) in short-chain fatty acid (SCFA) was significantly decreased by challenge (P< 0.05). CC and BEC groups had lower villus height to crypt depth ratio (V/C) and higher pathological scores in duodenum (P< 0.05), whereas the BEC group had lower pathological scores in jejunum when compared with the CC group (P< 0.05). The challenge increased the concentration of proinflammatory cytokines (IL-1β and IL-6) (P< 0.05). An increase in the abundance of Bacteroidoes(genus), Bacteroidaceae(family), Bacteroidoes sp Marseille P3166(species), Bacteroidoes caecicola(species) was observed in the CC group, whereas the BEC group had higher abundance of Bacteroides caecigallinarum(species). The genera Faecalibacteriumand Asterolplasmawere positively correlated with egg laying rate (r= 0.57, 0.60; P < 0.01); and the genera Bacteroidesand Romboutsiawere negatively correlated with egg-laying rate (r= -0.58, -0.74; P< 0.01). The genera Bacteroides, Lactobacillusand Rombutziawere positively correlated with jejunal mucosa pro-inflammatory factor IL-1β level (r = 0.61, 0.60, 0.59; P< 0.01), which were negatively correlated with genera Rikenbacteriaceae RC9, Faecalibacteriumand Olsenlla(r = -0.56, -0.57, -0.61; P< 0.01).There genera UCG.005 was positively correlated with pro-inflammatory factor IL-6 level in jejunal mucosa (r = 0.58; P< 0.01), which was negatively correlated with Rikenbacteriaceae RC9(r = -0.62; P< 0.01). The experiment results revealed that the addition of BEC to the diet restored the production performance of the laying hens. In addition, supplementation of 2000 mg/kg BEC modulated gut health by reducing gut damage scores and modulating microbial composition, thereby promoting recovery of laying hens after coccidia and Clostridium perfringenschallenge.

Emerging evidence suggests an association between estrogen levels and reduced egg-laying performance as the layer became old. Since soy isoflavones (SF) have estrogen-mimic effects, whether it can enhance production performance and ovarian function of older layers is still not known. A total of 160 Lohmann pink layers (66-wk-old) were used in a 2 × 2 factorial design, which included 2 egg-laying levels [low (76.89 ± 1.65%; LOW) and normal (84.96 ± 1.01%; NOR)] and 2 different dietary groups [0 mg/kg SF, 20 mg/kg SF] were used. The results showed the NOR group had higher egg-laying rate, egg mass, and feed efficiency during the all phases (P(laying)< 0.05). The unqualified egg rate was lower in NOR group (9–12 wk, 1–12 wk) (P(laying)< 0.05). Dietary supplementation with SF increased the egg-laying rate and feed efficiency (5–8 wk, 9–12 wk, 1–12 wk), increased egg mass (9–12 wk, 1–12 wk) (P(SF)< 0.05). The NOR layers presented higher eggshell quality (redness, yellowness, brightness, eggshell ratio) at 12 wk (P(laying)< 0.05). Eggshell quality was found to be improved by SF (eggshell strength and eggshell thickness), egg albumen quality (higher albumen height and Haugh unit) at 12 wk (P(SF)< 0.05). Supplementing with SF led to an increase in eggshell strength in LOW group (P(laying*SF)< 0.05). The higher serum lever of glucose (GLU) and lower serum lever of follicle stimulating hormone (FSH) were in NOR group (P(laying)< 0.05). Supplementing SF in diets increased serum of estradiol (E2) and insulin-like growth factors-1 (IGF-1), decreased serum of FSH (P(SF)< 0.05). The NOR layers presented lower estrogen receptor α (ERα), estrogen receptor β (ERβ), B lymphoma 2 associated X protein (Bax), cytochrome c (Cytc), interleukin 6 (IL-6), caspase3, caspase9, IKKα, P50, and P65expression in the ovary (P(laying)< 0.05). Dietary SF supplementation decreased the anti-Müllerian hormone receptor (AMHR), Bax, caspase3, caspase9, Cytc, IL-6, IKKα, P50, P65expression in the ovary (P(SF)< 0.05). These findings indicated that layers with NOR group had higher production performance, egg quality, and ovarian function, while dietary supplementation with SF improved production performance and ovarian function by reducing inflammation and apoptosis-related genes expression in ovary.

The influence of nanocrystalline cellulose (NCC) supplementation on growth performance, carcass traits, intestinal development, and lipid metabolism was assessed in 600 one-day-old male meat ducks (Cherry Valley ducks) from 1 to 35 d of age. Diets were supplemented with 0, 200, 500, 800 and 1,500 mg/kg NCC during both the starter (1–14 d) and grower (15–35 d) phases. Each dietary treatment consisted of 8 replicate cages of 15 birds. Supplementation of NCC was associated with dose dependent increases in BW gain and feed intake (P < 0.01) during 1–14 d of age and in BW at 35 d of age. As NCC content increased, the percentage of breast meat weight (P < 0.05) and leg (with bone) weight (P < 0.05) linearly increased, while the percentage of abdominal fat weight (P < 0.01) linearly decreased in ducks at 35 d of age. Supplementation of NCC resulted in a dose-dependent increase in the weight (P < 0.05) and density (P < 0.01) of the cecum. The percentage of total hepatic lipid content (P < 0.01) at 14 d of age and serum triglyceride (TG) concentration (P = 0.052) at 35 d of age linearly decreased with increasing of dietary NCC addition. In conclusion, inclusion of 1,500 mg/kg NCC in feed resulted in the greatest improvements in duck performance, intestinal development and lipid deposition.

This study determined the effects of coated sodium butyrate (CSB) on production performance, egg quality, nutrient digestibility, and intestinal health of laying hens. We divided a total of 800 Lohmann laying hens, aged 51 wk, into 4 treatment groups: 0 (CON), 300 (CSB1), 500 (CSB2), and 800 (CSB3) mg/kg of CSB. Each group comprised 20 birds, with 10 replicates set. A 12-wk monitoring process was conducted for each laying hen. Compared to CON, dietary supplementation of CSB did not affect the average daily feed intake or the egg weight. The CSB3 group demonstrated a linear increase in the production performance (P< 0.05), with decreased feed conversion ratio (P< 0.05). CSB2 and CSB3 exhibited markedly elevated egg mass (P< 0.05). The CSB supplementation markedly enhanced the yolk color (P< 0.05). CSB1 improved the digestibility of dry matter (P = 0.029). No significant differences were observed among dietary treatments in the duodenal morphology (P> 0.05). The three dosages of CSB reduced the crypt depth (P< 0.05) in the jejunum, whereas CSB3 exhibited an increase in the villus height (VH; P =0.048). The CSB3 group showed a markedly elevated ileal VH (P =0.011). CSB supplementation significantly increased the butyric acid content in the cecum (P = 0.009). The hens fed on the 800 mg/kg CSB diet showed a significant increase (P = 0.029) in butyric acid content in the ileum. The CSB3 group showed an elevation in microbial diversity (P< 0.05). Additionally, at the phylum level, the CSB3 increased the enrichment of Bacteroidetes, the CSB2 increased Firmicutes, and the abundance of Deferribactereswas increased in CSB2 and CSB3 groups (P< 0.05). An enrichment of Muribaculaceae(family) was observed in the CSB3 group. In conclusion, dietary supplementation of CSB improved production, yolk color, intestinal morphology, butyrate content, and microbial composition in laying hens.

The purpose of this experiment is to explore the effects of dietary supplementation of benzoic acid, Enterococcus faecium, and essential oil complex (BEC) on coccidia and Clostridium perfringenschallenge in laying hens. A total of 80 Lohmann gray laying hens (35 wk old) were allocated to 4 treatments in a 2 × 2 factorial arrangement with the main effects of Clostridium perfringenstype A (CP) and coccidia challenge (with or without challenge) and 2 BEC levels (0 and 1,000 mg/kg). The total experimental period was 6 wk. The results showed that: the challenge group significantly decreased the laying rate and average daily feed intake (ADFI) of laying hens (PChallenge< 0.01). The BEC + challenge group significantly increased the laying rate and decreased the feed conversion ratio (FCR) of laying hens (PBEC< 0.05). The challenge significantly decreased the thickness, strength, and relative weight of eggshell (PChallenge< 0.05). The BCE + challenge group significantly increased the relative weight and strength of the eggshell (PBEC< 0.05). The challenge significantly increased the crypt depth of the duodenum, jejunum and ileum, and decreased the villus-to-crypt ratio (V/C) (PChallenge< 0.01). The BEC + challenge group decreased the crypt depth of the duodenum and jejunum, and increased the V/C of the duodenum (PBEC< 0.01). The pathological scores of duodenum and jejunum of the challenge group were significantly higher than other groups (PChallenge< 0.01), while the BEC + challenge group had lower pathological scores of jejunum (PBEC< 0.01). The challenge significantly decreased the mRNA expression of Occludin, Mucin-2, Zonula occluden-1 (ZO-1)(Pchallenge< 0.05); whereas the BEC group significantly increased the expression of Occludin, Mucin-2, and Claudin-1mRNA (PBEC< 0.05). The challenge significantly increased the level of interleukin 1β (IL-1β) in the jejunum (PChallenge< 0.05). Taken together, adding BEC to the diet can improved production performance and egg quality of layers, by protecting intestinal health against Clostridium perfringenstype A (CP) and coccidia challenge.

Resveratrol (RV) is associated with protection against oxidative stress to improve health, however the effect of RV in layers under oxidative stress (OS) is limited. The objective of this experiment was to investigate the negative effect of OS and protective effects of RV against OS in laying hens. 40 Lohmann layers (25-wk-old; BW = 1.44±0.10 kg) were allocated to four treatments in a 2 × 2 factorial arrangement with either RV (0 or 600 mg/kg) or intraperitoneal injection of tert-butyl hydroperoxide (tBHP) (0 or 800 μmol/kg BW) for 31 days. The results shown that the hens challenged with tBHP presented lower egg-laying rate, feed intake, feed efficiency and higher defective egg rate (P(tBHP)<0.05). The RV were also observed to attenuated egg laying rate and feed intake reduction together with decreased broken egg rate under t-BHP challenge (P(Interaction)≤0.01). Eggshell quality (color, strength, thickness), albumen quality (albumen height, Haugh unit, albumen relative weigh) and yolk color were lower in tBHP challenge (P(tBHP)<0.05). The RV were observed to increase eggshell color (lower lightness, higher redness and yellowness values), yolk color and albumen relative weight under tBHP challenge (P(Interaction)<0.05). A decrease in the serum concentration of estradiol, follicle-stimulating hormone (FSH), anti-Müllerian hormone (AMH) and leptin were observed in the tBHP challenged layers (P(tBHP)<0.05). Feeding RV were found to increase FSH levels irrespective of tBHP challenge (P(RV)<0.05), while the increase in serum estradiol, AMH and leptin concentration were more pronounced when layers received RV diet under tBHP challenge (P(Interaction)<0.05). The tBHP challenged layer demonstrated lower intestinal morphology (villus height in duodenum and jejunum), lower antioxidant enzymes activities [total superoxidase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC)], and glutathione (GSH) levels and higher malondialdehyde (MDA) level] (P(tBHP)<0.05). Dietary RV increased jejunal SOD, GSH-Px and T-AOC activities, and reduced MDA concentration (P(RV)≤0.05). Layers under tBHP challenge up-regulated mRNA expression of pro-inflammatory cytokine [interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)] and nuclear factor NF-κB(P(tBHP)<0.05) in jejunum.Dietary RV supplementation down-regulated mRNA gene expression of IL-1β, IL-6, TNF-αand NF-κB(P(RV)≤0.05). Moreover, layers under t-BHP challenge had lower mRNA expression of barrier-related proteins (claudin-1, claudin-2, mucin-1, and occludin) (P(tBHP)<0.05) in jejunum mucosa. Dietary RV up-regulated mRNA expression of jejunal barrier-related proteins (claudin-1, claudin-2, mucin-1, and occludin) and ovarian reproductive hormone receptor [steroidogenic acute regulatory protein (StAR), androgen receptor (AR), estrogen receptor 1 (ESR1), and activin a receptor type 1 (ACVR1)] (P(RV)≤0.05). Overall, the results indicate that tBHP induced oxidative stress to result in reducing production performance, egg quality, intestinal health and induced ovarian inflammation; whereas dietary RV was able to maintain intestinal health and mitigate the negative impact of tBHP challenge on production performance and egg quality.

The objective of this experiment was to investigate the influence of dietary tributyrin on reproduction performance and ovary function of broiler breeders with different egg laying rate. Two hundred fifty-six AA broiler breeders (48-wk-old) were allocated to 4 treatment in a 2 × 2 factorial arrangement with the main effects of tributyrin supplementation (0 and 1,000 mg/kg tributyrin [TRI]) and 2 egg laying rate levels (average [AR, 81.01 ± 0.79%] and low [LR, 70.98 ± 0.95%]). The results shown that the LR breeders presented higher egg weight, but lower egg laying rate, qualified egg rate and feed efficiency than the AR breeders (P(laying)< 0.05). Also, the superoxidase dismutase (SOD) activity in magnum was lower while malondialdehyde (MDA) was higher in ovary and magnum of LR breeders than that in the AR breeders (P(laying)< 0.05). Dietary supplementation with tributyrin significantly enhanced egg weight (P(TRI)< 0.05), increased albumen height as well as Haugh unit (HU) in AR breeders (P(interaction)< 0.05), and also had higher total antioxidant capacity (T-AOC) and lower MDA in ovary (P(TRI)< 0.05). The cell apoptosis rate and proapoptosis related gene expression (caspase 8, 9and Bax) in the ovary of LR breeders was higher, while anti-apoptosis related gene (Bcl-2) expression were lower in LR breeders when compared with the AR breeders (P(laying)< 0.05). Dietary supplementation with tributyrin decreased the cell apoptosis rate and downregulated caspase 9expression in LR breeders (P(Interaction)< 0.05), up-regulated the Bcl-2expression in both 2 breeders (P(TRI)< 0.05). These findings suggest that the breeders with lower egg laying rate also characterized by deteriorate ovary function indicated by lower antioxidant capacity and higher cell apoptosis rate. Dietary supplementation with tributyrin increased egg albumen quality, decreased ovarian proapoptosis related gene expression to improve reproductive tract function; and the positive effect on egg albumen quality is more pronounced in average reproductive breeders.

The high stocking density is a major stress factor that adversely affects the health and performance of poultry. Therefore, the object of this study was conducted to explore whether dietary 25-hydroxyvitamin D (25-OH-D3) could improve gut health of laying hens reared under high stocking density. A 2 × 2 factorial design was used in this 16-week study, in which 800 45-week-old Lohmann laying hens were allocated into two levels of dietary 25-OH-D3levels (0 and 69 µg/kg) and two rates of stocking densities [506 (low density, LD) and 338 (high density, HD) cm2/hen]. Compared with the layers with LD, the layers with HD had lower crypt depth in duodenum (P(Density)< 0.05), lower short chain fatty acid (propionic and butyric acid) contents in cecum (P(Density)< 0.05), and lower mRNA expression of intestinal barrier associated protein (claudin-1, mucin-1 and mucin-2). Exposed layer to HD also led to lower intestinal antioxidative capacity [superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and higher malondialdehyde (MDA) content] in small intestine (P(Density)< 0.05), lower bacterial abundance of Bacteroidetes(phylum), Spirochaetes(phylum) and Bacteroides(genus; P(Density)< 0.05), higher bacterial enrichment of Lactobacillaceae(genus) and Firmicutes/Bacteroidetesratio (P(Density)< 0.05) in cecum. Dietary 25-OH-D3increased the villus height in duodenum and jejunum (P(25-OH-D3)< 0.05), decreased Chao 1 and ACE indexes in cecum (P(25-OH-D3)< 0.05), and it also up-regulated the mRNA expression of claudin-1, mucin-1 and mucin-2 (P(25-OH-D3)< 0.05). Layers treated with 25-OH-D3led to an enhanced antioxidative enzyme activity of CAT (P(25-OH-D3)< 0.05). Additionally, the effect of 25-OH-D3reversed the effect of HD on T-AOC and MDA content (P(Interaction)< 0.05). In HD layers, 25-OH-D3administration decreased the enrichment of Bacteroidetes(phylum), increased Firmicutes(phylum), and Firmicutes/Bacteroidetesratio (P(Interaction)< 0.05). These results suggest that supplementing 25-OH-D3in diets may elevate gut health through the improvement of intestinal barrier function, antioxidant capacity and cecal microbiota composition in laying hens with high stocking density.

Reproduction performance is one of the most important economic traits for the poultry industry. Intriguingly, apple pectic oligosaccharide (APO) could promote gastrointestinal function and immune function to improve performance; however, literature about APO on reproduction performance in breeders is limited. This study aimed to determine whether APO administration can improve reproduction performance and ovary function of broiler breeders with different egg laying rates. Two hundred and fifty six Arbor Acres broiler breeders (48-week-old) were used in a 2 × 2 factorial design with 2 egg laying rates (average [AR] and low [LR]) and 2 dietary levels of APO (0 and 200 mg/kg APO). Results showed that the LR breeders presented higher egg weight but lower egg laying rate, qualified egg rate, and feed efficiency than the AR breeders (P(laying) < 0.05). Also, the LR breeders had decreased serum Anti-Müllerian hormone, leptin, and antioxidant enzyme (superoxide dismutase, total antioxidant capacity) levels than the AR breeders (P(laying) ≤ 0.05). Dietary supplementation with APO improved egg weight, feed efficiency, as well as egg albumen quality (higher albumen height and Haugh unit) (P(APO) < 0.05), and decreased the concentration of pro-inflammatory cytokine levels (interleukin [IL]-1β, IL-8) in serum (P(APO) ≤ 0.05). The apoptosis rate and pro-apoptosis-related gene expression (caspase 9and Bax) in the ovary of LR breeders were higher, while the anti-apoptosis-related gene expression (Bcl-2, PCNA) was lower in LR compared with the AR breeders (P(laying) < 0.05). Dietary supplementation with APO decreased the caspase 9and Baxexpression in LR breeders (P(interaction) < 0.05), and increased the Bcl-2and PCNAexpression in the 2 breeders (P(APO) < 0.05). These findings indicate that breeders with a lower egg laying rate exhibit lower antioxidant capacity and high cell apoptosis in the ovary. Dietary supplementation with APO might improve albumen quality and antioxidant capacity, and decrease the inflammatory factors and ovary apoptosis-related genes expression to improve ovary function. Moreover, the effect of APO on decreasing ovarian pro-apoptosis-related gene expression was more pronounced in lower reproductive breeders.

This study was conducted to explore whether dietary pectic oligosaccharide (POS) supplementation could improve gut health of broiler breeders with different egg-laying rates. A 2 × 2 factorial design was used in this study. Two hundred fifty-six Arbor Acres broiler breeders (48 wk of age), including 128 average egg-laying rate and 128 low egg-laying rate (LELR) birds, were randomly fed with the diets supplemented with or without 200 mg kg−1of POS (n = 8). The trial lasted for 8 wk. Compared with average egg-laying rate broiler breeders, LELR broiler breeders had lower laying rate and qualified egg rate (P < 0.05), higher egg weight and feed conversion ratio (P < 0.05), higher malondialdehyde (MDA) levels in the jejunum (P < 0.05), higher IL-6(P < 0.05) and tumor necrosis factor α (TNF-α) (P = 0.07) mRNA expressions in the jejunal mucosa, and lower microflora diversity in cecal digesta. Dietary POS supplementation increased egg weight of broiler breeders (P < 0.05), enhanced superoxide dismutase activity in the jejunum (P < 0.05), decreased MDA level in the jejunum (P < 0.05), upregulated zonula occluden 1 mRNA expression in the jejunal mucosa (P < 0.05), downregulated IL-6and TNF-αmRNA expressions in the jejunal mucosa (P < 0.05), and regulated relative abundance of some microbiota (including the phylum and genus, P < 0.05). In addition, in LELR broiler breeders, POS administration enhanced villus height (P = 0.08) and ZO-2mRNA expression (P = 0.09) in the jejunal mucosa, alleviated the increasing MDA level in the jejunum (P < 0.05) and IL-6and TNF-αmRNA expressions in the jejunal mucosa (P < 0.05), and regulated relative abundance of some microbiota (including the phylum and genus, P < 0.05). These results suggest that supplementing POS in diets may elevate gut health via improvement of intestinal barrier function, antioxidant capacity, and microbiota composition in broiler breeders with different egg-laying rates.

Sinapine derived from cruciferous plants could be converted into trimethylamine by intestinal microbiota. Its metabolite, trimethylamine N-oxide (TMAO), is closely linked to increased risk of cardiovascular disease and fat deposition in mammals. Hens fed with rapeseed meal (RSM) suffered from fatty liver hemorrhage syndrome (FLHS). This study was conducted to investigate whether fatty liver induced by RSM is due to TMAO via altered microbiota composition and diversity. At 33 weeks of age, 600 laying hens were randomly divided into 5 treatment groups, namely control and 14% RAM treatment groups (DY5, with 16.2% erucic acid [EA] and 74.66% glucosinolate [Gl] contents; MB1, with 3.50% EA and 43.23% Gl contents; DY6, 6.7% EA and 22.67% Gl contents; XH3, with 44.60% EA and 132.83% Gl contents) for 8 weeks. Results revealed that three hens died due to liver hemorrhage after ingesting 14% RSM diet. The 14% RSM decreased serum low-density lipoprotein cholesterol (LDL-C) content (P< 0.01) while tended to increase serum TMAO content compared to the control group (P= 0.08). The 14% RSM diet increased red oil O optical density (P< 0.01), and increased total cholesterol (TC) and LDL-C content in the liver (P< 0.01, and P< 0.01, respectively). The 14% RSM decreased liver total bile acid (TBA) content compared to the control (P< 0.01). The DY6 had a higher TBA content in the liver than the XH3 (P< 0.01). The 14% RSM decreased mRNA abundance of liver X receptors alpha (LXR-α, P= 0.01), and increased mRNA abundance of sterol response element binding protein 2 (SREBP-2, P= 0.04). Results revealed that the in-feed RSM could alter richness and diversity of cecal microbiota compared to the control (P< 0.05). Liver TC content and serum TMAO showed a negative relationship with Proteobacteria and Actinobacteria (P= 0.04). In conclusion, 14% RSM increased liver TC and induced high liver score of FLHS, which was possibly associated with the altered cecal microbiota composition, increasing serum TMAO levels and regulation of LXR-αand SREBP-2expression.