The adaptability of Hy-Line Brown laying hens to low-phosphorus diets supplemented with phytase.

Body phosphorus homeostasis network allows laying hens to adapt to wide range of changes in dietary phosphorus levels. Phytase hydrolyzes phytate rendering phosphorus and reduces the laying hens' requirements for inorganic phosphate rock. Here, we demonstrate that there is no need to keep large safety margins in dietary phosphorus when hens are fed with phytase. Hy-Line Brown laying hens (n = 504) were randomly assigned to 7 treatments (6 replicates of 12 birds). A corn-soybean meal-based diet, with no inorganic phosphate rock, was formulated to contain 0.12% nonphytate phosphorus (nPP), 3.8% calcium, and 2,000 FTU/kg phytase. Inorganic phosphate rock (di-calcium phosphate) was supplemented into the basal diet to create 6 other diets containing 0.17, 0.22, 0.27, 0.32, 0.37, and 0.42% nPP. Levels of calcium carbonate and zeolite powder were adjusted to make sure all the 7 experimental diets contained the same nutrition levels (including calcium and phytase) except nPP. The diets were subjected to laying hens from 29 to 40 wk of age. As a result, when supplemented with 2,000 FTU/kg phytase, extra supplementation of inorganic phosphate rock had no effects (P > 0.05) on serum phosphorus levels, serum calcium levels, laying performance (laying rate, egg weight, feed intake, feed-to-egg ratio, and unqualified egg rate), egg quality (shell thickness, shell strength, albumen height, yolk color, and Haugh unit), and tibia quality parameters (breaking strength and ash, calcium, and phosphorus contents). Extra supplementation of inorganic phosphate rock linearly increased (P < 0.01) fecal phosphorus excretion and linearly decreased (P = 0.032) the apparent metabolizability of dietary phosphorus. While serum hormones and intestine gene expressions were varied within treatments, no consistent changes were found. In conclusion, the supplementation of inorganic phosphate rock (provided 0.05-0.30% extra nPP) to phytase-containing basal diets (2,000 FTU/kg; nPP = 0.12%) provided limited benefits to egg production performance in laying hens from 29 to 40 wk of age. Further investigating the body phosphorus homeostasis would help to understand the nutritional and physiological reasonability of formulating low-phosphorus diets in the laying hen industry.

Effects of in ovo feeding of vitamin C on post-hatch performance, immune status and DNA methylation-related gene expression in broiler chickens.

This study aimed to evaluate the effect of in ovo feeding (IOF) of vitamin C at embryonic age 11 (E11) on post-hatch performance, immune status and DNA methylation-related gene expression in broiler chickens. A total of 240 Arbor Acres breeder eggs (63 (sem 0·5) g) were randomly divided into two groups: normal saline and vitamin C (VC) groups. After incubation, newly hatched chicks from each group were randomly divided into six replicates with ten chicks per replicate. Hatchability, average daily feed intake (D21-42 and D1-42), and average daily gain and feed conversion ratio (D1-21) were improved by vitamin C treatment (P < 0·05). IOF of vitamin C increased vitamin C content (D1), total antioxidant capacity (D42), IgA (D1), IgM (D1 and D21), stimulation index for T lymphocyte (D35) and lysozyme activity (D21) in plasma (P < 0·05). On D21, vitamin C increased the splenic expression of IL-4 and DNMT1 and decreased IL-1ß, Tet2, Tet3 and Gadd45ß expression (P < 0·05). On D42, vitamin C increased the splenic expression of IL-4 and DNMT3A and decreased IFN-γ, Tet3, MBD4 and TDG expression (P < 0·05). In conclusion, the vitamin C via in ovo injection can be absorbed by broiler's embryo and IOF of vitamin C at E11 improves the post-hatch performance and immune status and, to some extent, the antioxidant capacity of broiler chickens. The expression of enzyme-related DNA methylation and demethylation indicates that the level of DNA methylation may increase in spleen in the VC group and whether the fluctuating expression of pro- and anti-inflammatory cytokines is related to DNA methylation change remained to be further investigated.

Spermatozoal mRNAs expression implicated in embryonic development were influenced by dietary folate supplementation of breeder roosters by altering spermatozoal piRNA expression profiles.

Dietary folate intake, together with changes in its metabolism process, have effects on male reproduction, sperm epigenetic patterning and offspring outcome. Previous studies have proven that PIWI-interacting RNAs (piRNAs) play important roles in successful spermatogenesis and regulating genes expression of sperm and offspring embryo. Herein, we fed breeder roosters with five different levels (0, 0.25, 1.25, 2.50, and 5.00 mg/kg) of folate throughout life and found that paternal folate supplementation was beneficial to the growth and organ development of offspring broilers. Further spermatozoal mRNAs sequencing analyses implied that the dietary folate supplementation could regulate the spermatozoal mRNA abundance of genes related to the fetal development. Furthermore, global piRNAs analyses of breeder roosters' sperm revealed that differential concentration of dietary folate supplementation could change piRNAs profiles. Combined mRNAs sequencing and target gene prediction of differentially expressed gene-derived piRNAs, embryonic development and metabolism related pathways and biological processes, which were consisted to the regulatory roles of paternal folate supplementations, were significantly affected by the differentially expressed gene-derived piRNAs based on the GO and KEGG analyses. Overall, our results provided a novel insight into the role of piRNAs in response to folate intake, which will broaden the understanding about the relationship between folate and sperm epigenetic patterning of breeder roosters.

Effects of glucose oxidase on growth performance, gut function, and cecal microbiota of broiler chickens.

A study was conducted to study the effects of glucose oxidase (GOD) supplement on the growth performance, gut function, and cecal microbiota in broiler chickens from 1 to 42 d, and further evaluate the use of GOD as an antibiotic substitution. A total of 525 1-d-old healthy Arbor Acres broilers were randomly assigned to five treatments, including control group, antibiotic growth promoters (AGP) supplement group, and three GOD supplement groups, with seven replicates per treatment and 15 birds per replicate. Growth performance, gut function including digestive ability and gut barrier, and cecal microbiota were determined. Compared with the control group, the increased daily body weight gain, improved meat quality, and enhanced digestive ability that indicated from the nutrients apparent digestibility and digestive enzymes were identified in GOD supplement groups, which could have a similar effect with the AGP supplement. The content of secreted immunoglobulin A and the transepithelial electrical resistance were also increased with the GOD supplement, which indicated an enhanced gut barrier. Additionally, 16S rRNA gene of cecal contents was sequenced by high-throughput sequencing. Sequencing data indicated that the Firmicutes phylum, Ruminococcaceae and Rikenellaceae families, Faecalibacterium genus, and F. prausnitzii species were significantly altered. Especially, combined with previous studies, our results indicated that the significantly increased F. prausnitzii, Ruminococcaceae, and Firmicutes could be involved in the effect of GOD on gut function and growth performance of broilers. Our results indicated that dietary GOD supplement could improve the growth performance of broilers in two main ways: by enhancing the digestive function of gut, which concluded from the improved nutrients apparent digestibility and digestive enzyme, and by increasing the abundance of beneficial bacterium, such as F. prausnitzii, Ruminococcaceae, and Firmicutes, which could be further served as an important regulator to improve the growth performance and the gut health.

Simultaneous Supplementation of Bacillus subtilis and Antibiotic Growth Promoters by Stages Improved Intestinal Function of Pullets by Altering Gut Microbiota.

Early nutrition of pullets could determine the overall development and the performance of laying hens. With the aim to reduce the use of antibiotic growth promoters (AGPs) and to maintain the growth and development of pullets, the effect of simultaneous short-termed supplementation of AGPs (bacitracin zinc 20 mg/kg and colistin sulfate 4 mg/kg) and Bacillus subtilis (B. subtilis) DSM17299 probiotic, as well as the effect of supplementation of AGPs (bacitracin zinc 20 mg/kg and colistin sulfate 4 mg/kg) during the whole period (0~16 weeks) on the overall growth and development, intestinal health, and caecal microbiota of pullets were evaluated. In the present study, a total of 630 one-day-old Hy-Line Brown layers were randomly distributed into five equal groups: including the AGPs group (supplemented with AGPs based on basal diets for 16 weeks), the BA3 group (supplemented with AGPs and B. subtilis based on basal diets for 3 weeks), the BA6 group (for 6 weeks), the BA12 group (for 12 weeks), and the BA16 group (for 16 weeks). When compared with the AGPs group, the supplementation of AGPs + B. subtilis for the first 3 weeks could maintain overall growth performance, including the average body weight, average feed intake, average daily weight gain, and feed conversion ratio of pullets at 3, 6, 12, and 16 weeks of age (P > 0.05). Meanwhile, the characteristic growth indexes in different periods were separately measured. At 3 weeks of age, the amylase activity in ileum was elevated (P = 0.028), and the length of tibia was up to the standard in the BA3 group. At 12 weeks of age, the increased villus height (P = 0.046) of jejunum, increased villus height (P = 0.023) and ratio of villus height to crypt depth (P = 0.012) of ileum, decreased crypt depth (P = 0.002) of ileum, and elevated mRNA levels of sucrase in jejunum (P < 0.05) were all identified in the BA3 group. At 16 weeks of age, the secreted immunoglobulin A (sIgA) content in the jejunum mucosa of the BA3 group was greater than the other groups (P < 0.001). Furthermore, altered intestinal microbiota was found in the BA3 group. Specifically, decreased amounts of Alistipes, Bacteroides, Odoribacter, Dehalobacterium, and Sutterella and increased amounts of Lactobacillus, Dorea, Ruminococcus, and Oscillospira were determined (P < 0.05) in the BA3 group at week 6. Meanwhile, decreased amounts of B. fragilis and C. leptum (P < 0.05) were identified in the BA3 group at week 12, which were found to be relevant for the improvement of intestinal morphology (P < 0.05) by Pearson analysis. In conclusion, simultaneous supplementation of AGP and B. subtilis for 0~3 weeks increased the relative abundance of beneficial microbiota in caecum in 0~6 weeks, then improved the intestinal morphology by elevating populations of B. fragilis and C. leptum in 7~16 weeks, and further upregulated sucrase expression and increased sIgA content in the intestinal mucosa in 13~16 weeks.

Transgenerational endotoxin tolerance-like effect caused by paternal dietary Astragalus polysaccharides in broilers' jejunum.

To learn the nutri-epigenetics role of Astragalus polysaccharides (APS), we designed and studied the transgenerational effect of paternal dietary APS supplementation in chickens. 160 Avein breeder cocks were randomly allocated into 5 groups and fed with 0, 0.01, 0.1, 1, and 10 g/kg APS supplement, respectively. Sperm of breeder cocks was collected and used for hatching experiment to get broiler chickens when the cocks at 40-weeks-old. It showed that the paternal dietary 10 g/kg APS could transgenerational promote growth performance and jejunal tissue morphology of chickens. As to phenotypes, 10 g/kg APS treatment was chosen for molecular assays. In jejunal mucosa, 10 g/kg dietary APS didn't have any systematic effect on gene transcription of breeder cocks, whereas, the APS could induce transgenerational endotoxin tolerance-like effect through activating the IFNα-SOCS1 pathway in chicks. In both jejunum and sperm, the promoter methylation level of SOCS1 significantly reduced in 10 g/kg APS treatment versus the control group. In addition, the paternal APS significantly affected histone modification in promotor region of TRIF. Our data revealed that the paternal dietary APS supplementation could induce transgenerational endotoxin tolerance-like effect in jejunum mucosa of broiler chickens. And nutri-epigenetic modifications are crucial for this transgenerational effect.

Effects of a protected inclusion of organic acids and essential oils as antibiotic growth promoter alternative on growth performance, intestinal morphology and gut microflora in broilers.

This experiment was conducted to investigate the effects of protected essential oils and organic acids mixture on poultry feeding. A total of 450 1-day-old Cobb 500 chicks were randomly allotted into three treatments with six replicates. Birds were offered a basal diet (C), basal diet with 0.15 g/kg enramycin premix (A) and basal diet with 0.30 g/kg protected essential oils and organic acids mixture product (P). The results showed that protected essential oils and organic acids mixture supplementation reduced average daily feed intake and ratio of feed to gain (F/G) at 22-42 days of age, and F/G during 1-42 days of age also declined (P < 0.05). Product supplementation improved spleen index, villus height and crypt depth of the jejunum at 42 days when compared with the control (P < 0.05). In addition, secretory immunoglobulin A level of ileal mucosa and trypsin and chymotrypsin activities of intestinal tract were higher in the P treatment. Bacterial sequence analysis of the intestinal tract revealed that protected essential oils and organic acids mixture supplementation changed gut microflora mainly in Lactobacillus. These data suggested that dietary mixture of organic acids and essential oils addition could be used in the poultry industry as an antibiotic growth promoter alternative.