Partition of variation for predicting experimental power with a broiler chicken example.

A 1932 editorial in Poultry Science stated that sampling theory, or experimental power, could be useful for "the investigator to know how many … birds to put into each experimental pen." Nevertheless, in the past 90 yr, appropriate experimental power estimates have rarely been applied to research with poultry. To estimate the overall variation and appropriate use of resources with animals in pens, a nested analysis should be conducted. Bird-to-bird and separate pen-to-pen variances were separated for 2 datasets, one from Australia and one from North America. The implications of using variances for birds per pen and pens per treatments are detailed. With 5 pens per treatment, increasing birds per pen from 2 to 4 decreased the SD from 183 to 154, but increasing birds/pen from 100 to 200 only decreased the SD from 70 to 60. With 15 birds per treatment, increasing pens/treatment from 2 to 3 decreased SD from 140 to 126, but increasing pens/treatment from 11 to 12 only decreased the SD from 91 to 89. Choosing the number of birds to include in any study should be based on expectations from historical data and the amount of risk investigators are prepared to accept. Too little replication will not allow relatively small differences to be detected. On the other hand, too much replication is wasteful in terms of birds and resources, and violates the fundamental principles of the ethical use of animals in research. Two general conclusions can be made from this analysis. First, it is very difficult to detect 1% to 3% differences in broiler chicken body weight with only one experiment consistently because of inherent genetic variability. Second, increasing either birds per pen or pens per treatment decreased the SD in a diminishing returns fashion. The example presented here is body weight, of primary importance to production agriculture, but it is applicable whenever a nested design is used (multiple samples from the same bird or tissue, etc.).

Spray-dried porcine plasma enhances feed efficiency, intestinal integrity, and immune response of broilers challenged with necrotic enteritis.

Re-emergence of enteric diseases in the postantibiotic era has imposed severe loss to the poultry industry leading to the urgent need for appropriate additives to maintain gut health. Recently, more attention has been paid to animal plasma due to its high concentrations of active components such as albumins and globulins. The objective of this study was to evaluate the effects of spray-dried porcine plasma (SDP) supplementation during the starter phase (d 0-10) on growth performance, intestine health, and immune response of broilers under necrotic enteritis (NE) challenge. A total of 720 day-old male broiler parental line chicks (Ross 308) were randomly assigned to a 2 (NE challenge: no, yes) × 2 (SDP: 0, 2%) factorial arrangement with 12 replications of 15 chicks each. To induce NE, birds were inoculated with live Eimeria vaccine on d 9 and Clostridium perfringens on d 14. The body weight of birds and feed consumption were measured per pen on d 8, 10, 24, and 29 to calculate performance parameters. On d 16, three birds per pen were sampled to analyse the intestinal lesion score, gut permeability, villi morphology, relative weight of organs, and immune response. Results showed that SDP improved (P < 0.001) FCR in the pre-challenge phase (d 0-8). The results indicated that supplementing SDP lowered (P < 0.01) FCR at the end of the experiment (d 29). Dietary SDP decreased (P < 0.05) the concentration of FITC-d in serum samples of challenged broilers, although it did not affect the intestinal morphology and lesion score. Birds fed with SDP had a higher (P < 0.05) relative weight of bursa (g/kg live body weight) compared to non-supplemented birds. Supplementing SDP reduced the concentration of interleukin-6 (P < 0.05) and α-1 acid glycoprotein (P = 0.051) in serum samples of broilers. In conclusion, supplementation of SDP in the starter phase enhanced feed efficiency and gut integrity in NE challenged broilers, possibly through manipulating the immune response, while further studies targeting intestinal microflora and key genes are required to explore the mode of action.

[Analysis of HIV-1 genetic subtype and pretreatment drug resistance among men who have sex with men infected with HIV-1 from 19 cities of 6 provinces in China].

Objective: To investigate the distribution of HIV-1 genetic subtypes and pretreatment drug resistance (PDR) among men who have sex with men (MSM) from 19 cities of 6 provinces in China. Methods: From April to November 2019, 574 plasma samples of ART-naive HIV-1 infected MSM were collected from 19 cities in Hebei, Shandong, Jiangsu, Zhejiang, Fujian, and Guangdong provinces, total ribonucleic acid (RNA) was extracted and amplified the HIV-1 pol gene region by nested polymerase chain reaction (PCR) after reverse transcription. Then sequences were used to construct a phylogenetic tree to determine genetic subtypes and submitted to the Stanford drug resistance database for drug resistance analysis. Results: A total of 479 samples were successfully amplified by PCR. The HIV-1 genetic subtypes included CRF01_AE, CRF07_BC, B, CRF55_01B, CRF59_01B, CRF65_cpx, CRF103_01B, CRF67_01B, CRF68_01B and unrecognized subtype, which accounted for 43.4%, 36.3%, 6.3%, 5.9%, 0.8%, 0.8%, 0.4%, 0.4%, 0.2% and 5.5%, respectively. The distribution of genetic subtypes among provinces is statistically different (χ2=44.141, P<0.001). The overall PDR rate was 4.6% (22/479), the drug resistance rate of non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, and protease inhibitors were 3.5% (17/479), 0.8% (4/479) and 0.2% (1/479), respectively. The PDR rate of recent infections was significantly higher than that of long-term infections (χ2=4.634, P=0.031). Conclusions: The HIV-1 genetic subtypes among MSM infected with HIV-1 from 19 cities of 6 provinces in China are diverse, and the distribution of subtypes is different among provinces. The overall PDR rate is low, while the PDR rate of recent infections was significantly higher than that of long-term infections, suggesting the surveillance of PDR in recent infections should be strengthened.

Dietary soluble non-starch polysaccharide level and xylanase influence the gastrointestinal environment and nutrient utilisation in laying hens.

1. The objective of this study was to examine the influence of dietary soluble non-starch polysaccharide (sNSP) level and xylanase supplementation on productive performance, viscosity and pH along the gastrointestinal tract in laying hens. Excreta moisture content, ileal and caecal microbiota and short-chain fatty acid (SCFA) composition and apparent total tract nutrient utilisation were measured.2. Hyline Brown laying hens (n = 144) were housed individually at 25 weeks of age and allocated to one of the four wheat-based dietary treatments in a 2 × 2 factorial arrangement, consisting of two levels of sNSP (High 13.40 g/kg or Low 11.22 g/kg), with or without xylanase (0 or 12,000 BXU/kg). Birds were fed the dietary treatments for 56 d.3. Increasing dietary sNSP increased jejunum viscosity, degradability of total NSP, total tract flow of insoluble arabinose, and succinic acid concentration in the caeca (P < 0.05). Feeding high sNSP decreased excreta moisture content, total tract energy retention and free oligosaccharide, total tract flow of soluble and insoluble galactose and insoluble rhamnose and fucose, and ileal acetic and lactic acid concentrations (P < 0.05), and tended to reduce egg production (P = 0.058).4. Supplementation with xylanase resulted in reduced jejunum and ileum viscosity, caecal pH, excreta moisture, flow of soluble arabinose and glucose and insoluble arabinose and xylose, caecal concentration of Lactobacillus sp. and isobutyric and succinic acid, and ileal concentration of Bacillus sp. and total anaerobic bacteria (P < 0.05). Xylanase application also increased energy retention and insoluble and total NSP degradation, and caecal abundance of Bifidobacteria sp. and valeric acid (P < 0.05).5. These results reiterated the ability of xylanase to improve nutrient digestibility and reduce excreta moisture content in laying hens, and highlighted the importance of considering dietary sNSP level in laying hen diets.

[The molecular mechanism of oxaliplatin-induced peripheral neuropathic pain].

Objective: To investigate the molecular mechanism of oxaliplatin-induced chemotherapy-induced peripheral neuropathic pain (CIPNP). Methods: A total of 16 male Sprague-Dawley rats of specific pathogen-free grade were randomly divided into two groups: oxaliplatin experimental group (2.4 mg/kg oxaliplatin dissolved in 5.0% glucose solution, n=8) and control group (equal volume 5% glucose solution, n=8). The rat model of CIPNP was established by continuous administration with oxaliplatin. In addition, mechanical allodynia, thermal hyperalgesia and cold hyperalgesia were measured and compared between the two groups. To explore the molecular mechanism of oxaliplatin-induced CIPNP, the gene expression of dorsal root ganglia (DRG) from the rat model of CIPNP was analyzed using RNA sequencing (RNA-Seq). Results: Mechanical and thermal hypersensitivity was exhibited on day 7 and a stronger hypersensitivity was observed on day 14. A total of 20 152 genes were quantified by RNA-Seq, and 379 differentially expressed genes (DEGs) were obtained with absolute fold change cut-offs ≥ 2 and P value<0.05. There were 7 genes (Npy, Car3, Cdkn1a, Nts, Prc1, Ms4a7 and Ecel1) that were involved in peripheral nerve injury-related neuropathic pain. Gene ontology (GO) functional enrichment analyses indicated that the DEGs induced by oxaliplatin were involved in oxygen transport, cell division, intermediate, centromere, oxygen transporter activity, oxygen binding. Moreover, the result of Kyoto Encyclopedia of genes and genomes (KEGG) analyses highlighted that the DEGs induced by oxaliplatin were involved in malaria, African trypanosomiasis, primary immunodeficiency, peroxisome proliferator activated receptor (PPAR) signaling pathway. Conclusion: Oxaliplatin induces CIPNP via pain-related genes and signaling pathways.

Soluble non-starch polysaccharide modulates broiler gastrointestinal tract environment.

The aim of this study was to evaluate the importance of considering dietary soluble non-starch polysaccharides (sNSP) when formulating broiler diets, due to their impact on the gastrointestinal tract environment. Cobb 500 broilers (n = 480, 80 birds per treatment) were fed either wheat- or corn-soybean meal-based diets formulated to contain either a high, medium or low sNSP content, resulting in 6 dietary treatments in a 2 × 3 factorial arrangement of treatments. On d14 and d 35 of age, pH of the gizzard, ileum and caeca, ileum viscosity, caecal short chain fatty acid (SCFA) concentration, and ileal and caecal microbiota profile were determined. Ileal viscosity at d 35 was greater in birds fed high sNSP compared to low sNSP (P = 0.022). At both d 14 and d 35, birds fed the wheat-based diet presented higher ileal viscosity (P < 0.001) and lower ileal pH (P = 0.027 and P < 0.001, respectively) compared to those fed the corn-based diet. At d 14, birds fed low sNSP exhibited higher caecal pH (P = 0.010) and propionic, isobutyric and valeric acid concentrations (P = 0.035, P = 0.007 and P = 0.011, respectively), and lower ileal Lactobacillus content (P = 0.043), compared to birds fed high sNSP. This effect was also seen for total SCFA (P = 0.017) and acetic acid (P = 0.005) concentrations in the caeca at d 14, but only in birds fed wheat-, not corn-, based diets. At d 35, total caecal SCFA concentration was greater in birds fed the wheat-based diet with high sNSP level compared to those fed the corn-based diet with high or low sNSP level (P = 0.028). In comparison to birds fed corn, birds fed wheat presented greater caecal concentrations of acetic, butyric, lactic, and succinic acids (P = 0.001, P < 0.001, P = 0.003 and P = 0.007, respectively) and Bifidobacteria at d 35 (P = 0.003) and succinic acid at d14 (P = 0.041). However, caecal populations of Ruminococcus and concentrations of valeric acid at d14 and isobutyric acid at d 35 were greater in birds fed the corn- compared to wheat-based diets (P = 0.043, P = 0.019 and P < 0.001, respectively). These results illustrate that dietary sNSP concentration, as well as its composition, have a direct impact on gastrointestinal viscosity and pH, and fuel beneficial microbial species, resulting in production of SCFA. It appears to be particularly important to consider sNSP level when formulating wheat-based diets for broilers.

Zinc hydroxychloride supplementation improves tibia bone development and intestinal health of broiler chickens.

This study was conducted to investigate the effects of zinc (Zn), as a combination of oxide (ZnO) and sulfate (ZnSO4), compared with incremental levels of zinc hydroxychloride (ZH) on tibia traits, intestinal integrity, expression of selected jejunal genes, cecal short chain fatty acids and microbial composition in broilers. Day-old male Ross 308 chicks (n = 784) were randomly allocated to seven dietary treatments, each replicated seven times with 16 chicks per replication. The dietary treatments included a negative control diet (NC) with no supplemental Zn, a positive control (PC) with 100 mg/kg supplemental Zn from an ionic bound source combination (50 mg/kg ZnO + 50 mg/kg ZnSO4), and the NC diet supplemented with one of 20, 40, 60, 80, or 100 mg/kg Zn as ZH. The diets were fed over starter (1-14 d) and grower (14-35 d) phases, with tissue and digesta samples collected from 3 birds per replicate on days 14 and 35. The results showed that dietary Zn level had a significant effect on tibia breaking strength on d 35 (P < 0.05), and tibia Zn concentration both on d 14 and d 35 (P < 0.01). Dietary Zn levels linearly (P < 0.01) increased cecal lactic acid production, increased Lactobacillus, and decreased Bacillus and total bacteria counts (P < 0.05). Inclusion of 80 and 100 mg/kg Zn as ZH tended to upregulate the expression of claudin-1 (P = 0.088) and tight junction protein-1 (P = 0.086). The results obtained in this study suggest that a non-Zn supplemented diet can negatively influence tibia development and gut microbiota composition in broiler chickens. Higher supplemental Zn in the diet alters cecal microbiota population in favor of Lactobacillus and can decrease the total bacterial load. Supplemental Zn level in the feed have the potential to manipulate the jejunal gut integrity at a molecular level.

Sexing chickens (Gallus gallus domesticus) with high-resolution melting analysis using feather crude DNA.

Identification of sex in broiler chickens allows researchers to reduce the level of variation in an experiment caused by the sex effect. Broiler breeds commonly used in research are no longer feather sexable because of the change in their genetics. Other alternate sexing methods are costly and difficult to apply on a large scale. Therefore, a sexing method is required that is both cost effective and highly sensitive as well as having the ability to offer high throughput genotyping. In this study, high-resolution melting (HRM) analysis was used to detect DNA variations present in the gene chromodomain helicase DNA binding 1 protein (CHD1) on the Z and W chromosomes (CHD1Z and CHD1W, respectively) of chickens. In addition, a simplified DNA extraction protocol, which made use of the basal part of chicken feathers, was developed to speed up the sexing procedure. Three pairs of primers, that is, CHD1UNEHRM1F/R, CHD1UNEHRM2F/R, and CHD1UNEHRM3F/R, flanking the polymorphic regions between CHD1Z and CHD1W were used to differentiate male and female chickens via distinct melting curves, typical of homozygous or heterozygous genotypes. The assay was validated by the HRM-sexing of 1,318 broiler chicks and verified by examining the sex of the birds after dissection. This method allows for the sexing of birds within a couple of days, which makes it applicable for use on a large scale such as in nutritional experiments.

Probiotic Bacillus subtilis 29,784 improved weight gain and enhanced gut health status of broilers under necrotic enteritis condition.

The study investigated the benefit of a Bacillus subtilis probiotic (Bs 29,784) in necrotic enteritis (NE)-challenged broilers. Four treatments were performed with 312 male day-old Ross 308 reared in floor pens from day 0 to day 35: 2 groups fed control diet without or with NE challenge (CtrlNC and CtrlNE); 2 groups fed probiotic and antibiotic supplements in the control diet with NE challenge (ProNE and AntNE). Necrotic enteritis challenge procedures commenced with inoculation of Eimeria spp 1 mL/bird per os at day 9 and Clostridium perfringens EHE-NE18 (approximately 108 cfu/mL) 1 mL/bird per os at day 14 and day 15. Performance parameters were measured on day 16 and day 35. Lesion, cecal microbiota, and jejunal gene expression were analyzed on day 16. Necrotic enteritis challenge significantly suppressed the performance parameters compared with CtrlNC: 27% weight gain reduction, 11 points feed conversion ratio (FCR) increase at day 16, and 12% weight gain reduction, 5-point FCR increase at day 35. By day 35, ProNE and AntNE treatments enabled significantly higher weight gain (4 and 9%, respectively) than CtrlNE. Compared with CtlrNE and contrary to AntNE, ProNE treatment exhibited upregulation of genes coding for tight junctions proteins (CLDN1, JAM2, TJP1), cytokines (IL12, interferon gamma, TGFß), and Toll-like receptors (TLR5, TLR21) suggesting enhanced immunity and intestinal integrity. 16S NGS analysis of cecal microbiota at day 16 showed a decreased alpha diversity in challenged groups. Principal component analysis of operational taxonomic unit (OTU) abundance revealed that ProNE and AntNE grouped closely while both distantly from CtrlNC and CtrlNE, which were separately grouped, indicating the similar effects of ProNE and AntNE on the OTU diversity that were however different from both CtrlNC and CtrlNE. Microbiota analysis revealed an increase of genera Faecalibacterium, Oscillospira, and Butyricicoccus; and a decrease of genera Ruminococcus, Lactobacillus, and Bacteroides; and an increase of the Firmicutes-to-Bacteroidetes ratio in ProNE and AntNE groups compared with the CtlrNE group. It is concluded that Bs 29,784 may enable improved health of broiler chickens under NE conditions thus performance implications.

Efficacy of supplemental multi-carbohydrases in broiler diets depends on soluble arabinoxylan-to-total arabinoxylan content.

1. The objective of this study was to investigate the effect of multi-carbohydrase enzymes (MC) on net energy (NE), performance and gene expression in Cobb 500 broilers fed diets containing different levels of soluble and total arabinoxylan (sAX/tAX) ratios.2. The study employed a 2 × 3 factorial arrangement of treatments, with factors including with or without MC and three ratios of sAX/tAX: high (HS, 27.3%), intermediate (IS, 21.3%) and low (LS, 15.7%).3. Six dietary treatments were formulated, with each diet replicated five times in the calorimetric study (Experiment 1) and eight times for a floor pen feeding trial (Experiment 2).4. Experiment 1 showed significant (P < 0.01) MC × sAX/tAX interactions for apparent metabolisable energy (AME) and NE. These interactions indicated that the supplemental MC increased AME only in the HS diet, and NE in the HS and LS diets.5. Experiment 2 results showed MC × sAX/tAX interactions for feed conversion ratio (FCR, P < 0.01) and ileal digesta viscosity (P < 0.05), demonstrating that MC lowered FCR only in the LS-fed birds, and reduced digesta viscosity only in the HS-fed birds. Apparent ileal digestible crude protein (AID CP) was negatively correlated with ileal digesta viscosity (r = -0.735, P < 0.001), which suggested that increasing ileal digesta viscosity reduced AID CP.6. A significant (P < 0.05) MC × sAX/tAX interaction was observed for duodenal COX III mRNA gene expression, which indicated that this gene was upregulated in the IS-fed birds relative to the HS-fed birds, but only when MC was added. This gene was downregulated (P < 0.05) in the muscle in the presence of MC application in all diets.7. The results from this study showed that supplemental MC can improve NE and FCR in birds fed diets containing the low sAX/tAX ratios.

Upregulation of long noncoding RNA DLX6-AS1 promotes cell growth and metastasis in esophageal squamous cell carcinoma via targeting miR-577.

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "Upregulation of long noncoding RNA DLX6-AS1 promotes cell growth and metastasis in esophageal squamous cell carcinoma via targeting miR-577, by S.-B. Wu, H.-Q. Wang, published in Eur Rev Med Pharmacol Sci 2020; 24 (3): 1195-1201-DOI: 10.26355/eurrev_202002_20171-PMID: 32096208" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/20171.

Influence of meat and bone meal, phytase, and antibiotics on broiler chickens challenged with subclinical necrotic enteritis: 2. intestinal permeability, organ weights, hematology, intestinal morphology, and jejunal gene expression.

Undigested proteins entering the hindgut may favor the proliferation of Clostridium perfringens. Using phytase to eliminate the need for meat and bone meal (MBM) as a P source may reduce potential infection with C. perfringens. A study was conducted to determine the impact of MBM, phytase, and antibiotics (AB) on intestinal permeability and morphology, organ weights, and jejunal gene expression in Ross 308 chickens challenged with subclinical necrotic enteritis (NE). Male Ross 308-day-old chicks (672 each) were randomly allocated to 8 treatments with 6 replicate pens each housing 14 birds. A 2 × 2 × 2 factorial arrangement of treatments was used: MBM (no or yes); AB (no or yes-Zn bacitracin 100 in S and 50 ppm in G/F and salinomycin Na 60 ppm in all phases); phytase (500 or 1,500 FTU/kg, both using 500 FTU matrix values) using wheat-SBM-canola meal diets. Birds were challenged with Eimeria spp on day 9, and C. perfringens strain EHE-NE18 on day 14 and 15. An AB × MBM interaction (P < 0.05) was detected for relative gizzard weight (with contents) being lower in birds fed MBM and AB compared to those fed MBM and no AB. A MBM × AB interaction (P > 0.01) was detected for lymphocyte counts being lower with MBM and AB compared to MBM without AB. A phytase × AB interaction (P < 0.05) was observed for villi length being increased with high phytase and no AB compared to with AB. Inclusion of MBM increased (P < 0.05) blood FICT-d concentration, whereas AB decreased it (P < 0.05). Antibiotics increased RBC (P < 0.05), Hgb (P < 0.05), and PCV (P < 0.05) and expression of Ca-binding protein, CALB1 (P > 0.05). Inclusion of MBM decreased expression of MUC2 (P < 0.05). Results indicate that dietary MBM has a detrimental effect on gut health of broilers but this may be counteracted using AB.

Reducing protein and supplementing crystalline amino acids, to alter dietary amino acid profiles in birds challenged for subclinical necrotic enteritis.

Necrotic enteritis (NE) is an infection of the gastrointestinal tract and is estimated to cost the global poultry industry billions of dollars annually. A study was conducted to examine whether reducing the crude protein might offset the severity of NE in broilers experimentally challenged with Eimeria spp. on day 9 and Clostridium perfringens on days 14 and 15. Furthermore, increasing the dietary amino acid (AA) density of the diet was also examined owing to identified benefits of improving performance compromised from low protein (LP) diets or NE. A 2 × 2 × 3 factorial arrangement of treatments at 6 replicates per treatment was used with 972 Ross 308 cockerels fed wheat-sorghum-soy-based diets to 35 D. Factors were NE challenge: no or yes; protein: standard (SP) or LP; and AA density: 100% AA, 115% with only essential AA (115% EAA) increased, and 115% AA with both essential and nonessential AA (115% AA) increased. The performance was measured in grower (days 7-21), finisher (days 21-35), and overall (day 7-35) periods. In addition, on day 16, intestinal lesion score and cecal short-chain fatty acids were measured. Only in nonchallenged birds fed LP diets, 115% AA increased grower feed intake (P < 0.01) and body weight gain (P < 0.05) compared to 115% EAA treatments. Challenge increased jejunal lesions (P < 0.001) with no difference between dietary treatments. Finisher body weight gain was greater in nonchallenged birds fed the 115% AA diets than in challenged birds (P < 0.05). Feeding diets with higher nonessential AA encouraged faster recovery from NE challenge. When fed the SP diets, NE challenge increased cecal butyric acid (P < 0.01) and total short-chain fatty acids (P < 0.05). The nutrient matrix used in LP diets does not favor beneficial butyric acid-producing bacteria. Using LP diets to mitigate NE severity does not offset the predisposing effect of E. spp. when attacking the gastrointestinal tract, and NE recovery is favored when feeding SP diets or additional AA.

Influence of meat and bone meal, phytase, and antibiotics on broiler chickens challenged with subclinical necrotic enteritis: 1. growth performance, intestinal pH, apparent ileal digestibility, cecal microbiota, and tibial mineralization.

This study investigated the influence of meat and bone meal (MBM), phytase, and antibiotics (AB) on the performance, intestinal pH, ileal digestibility, cecal microbiota, and tibial mineralization in Ross 308 broilers challenged with necrotic enteritis (NE). A total of 672-day-old male Ross 308 chicks were allocated to 8 treatments with 6 replicate pens, with 14 birds each. The study employed a 2 × 2 × 2 factorial arrangement of treatments: MBM (no or yes), AB (no or yes, zinc bacitracin + salinomycin), and phytase level (500 or 1,500 FTU/kg; both using 500 matrix recommendations). Diets were based on wheat-soybean meal-canola meal. All birds were challenged with Eimeria spp on day 9 and Clostridium perfringens (C. perfringens) strain EHE-NE18 on day 14 and day 15. On day 21 (postchallenge), birds fed MBM had reduced weight gain (WG; P < 0.05) relative to without MBM. A 2-way phytase × AB interaction for WG on day 14 (P < 0.001) and day 21 (P < 0.001) and feed conversion ratio on day 21 (P < 0.001) and day 42 (P < 0.01) indicated positive effects of high phytase on bird performance in the presence of AB. On day 42, a 3-way MBM × phytase × AB interaction (P < 0.01) was observed for WG, showing high phytase increased WG with AB, relative to the birds without AB in the presence of MBM. A 2-way MBM × phytase interaction (P < 0.01) was observed for apparent ileal digestibility of Ca and P on day 16, whereby there was a notable reduction in Ca and P digestibility in birds fed MBM-free diets and a low phytase level, but with the high phytase level, Ca and P digestibility was not influenced by MBM. In conclusion, in NE challenged birds, high phytase has a beneficial effect on leg health and mineral utilization to the extent that it can replace MBM and has beneficial effects on bird performance in the presence of AB.

Using crystalline amino acids to supplement broiler chicken requirements in reduced protein diets.

Reducing dietary CP can reduce N pollution. Much research has been reported in corn-based diets; however, the amino acid (AA) profiles of wheat-based diets differ. Poor performance as a result of reduced protein (RP) has been overcome in corn-based diets with essential AA and glycine (Gly) supplementation. The current study examined RP levels and Gly in wheat-based diets. An industry standard protein (SP) diet plus 3 RP diets with and without Gly supplementation, to match the SP treatment at 0.713 and 0.648% digestible Gly for the grower and finisher periods respectively, were fed to male broilers from day 10 of age. Grower CP included 22.5, 20.6, 18.3, and 17.7% (days 10-21) and finisher CP included 19.7, 17.8, 16.2, and 15.5% (days 21-35). Performance, meat yield, N efficiency, water intake, and apparent ileal digestibility of N and AA were measured. No difference in body weight gain (BWG), feed intake, or feed conversion ratio (FCR) were observed at 20% CP compared to the SP treatment. However, further reducing protein reduced BWG (P < 0.001), feed intake (P < 0.001), and increased FCR (P < 0.001). Supplementation of 0.713% Gly in the grower period increased BWG (P < 0.001) and reduced FCR (P < 0.001). Relative meat yield was not affected by dietary protein, however reducing CP increased relative fat pad weight (P < 0.001). Nitrogen efficiency increased with decreased CP in both grower (R2 = 0.69) and finisher (R2 = 0.80) treatments. Water intake decreased (R2 = 0.83) with decreasing CP intake. Apparent ileal digestibility of AA and N were higher in RP diets (P < 0.05). The benefits of reduced water intake and increased N efficiency and the disadvantages of poor performance and increased body fat in RP corn-based diets have been identified in RP wheat-based diets. Furthermore, at 18.5% CP the supplementation of crystalline AA and Gly can maintain BWG and FCR observed in SP diets.

Upregulation of long noncoding RNA DLX6-AS1 promotes cell growth and metastasis in esophageal squamous cell carcinoma via targeting miR-577.

OBJECTIVE: Esophageal squamous cell carcinoma (ESCC) is the most malignant type of esophageal cancer. Although significant advances have been made in ESCC diagnosis and therapy, its poor pathogenesis and prognosis remain a life-threatening problem. Meanwhile, long noncoding RNAs (lncRNAs) exert a pivotal function in tumorigenesis. In this research, we aimed to explore the association between the aberrant expression of lncRNA DLX6-AS1 and the development and metastasis of ESCC. PATIENTS AND METHODS: DLX6-AS1 expression was monitored by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) in ESCC specimens. Moreover, experiments were conducted to detect the effect of DLX6-AS1 on the cell proliferation and metastasis of ESCC. In addition, the underlying mechanism was further explored through luciferase assays and RNA immunoprecipitation assay (RIP). RESULTS: DLX6-AS1 expression level was significantly higher in ESCC specimens. Moreover, cell proliferation and metastasis of ESCC cells could be inhibited via reducing DLX6-AS1 expression. Besides, DLX6-AS1 was regarded as an oncogene in ESCC. Furthermore, DLX6-AS1 acted as a competing endogenous RNA via sponging miR-577 in ESCC. CONCLUSIONS: In summary, DLX6-AS1 promotes development and metastasis of ESCC by sponging miR-577 and could be a potential therapeutic target.

Two different Clostridium perfringens strains produce different levels of necrotic enteritis in broiler chickens.

Subclinical necrotic enteritis (NE) is primarily caused by the gram-positive bacterium, Clostridium perfringens (Cp). The trend towards removal of in-feed antimicrobials and subsequent increased emergence of infection in poultry has resulted in a wide interest in better understanding of the mechanism behind this disease. The virulence of NE, to a large extent, depends on the virulence of Cp strains. Thus, this study was to assess how 2 different strains of Cp affect performance and gut characteristics of broiler chickens. Ross 308 male broilers (n = 468) were assigned to a 2 × 3 factorial arrangement of treatments with antibiotics (Salinomycin at 72 ppm and zinc bacitracin at 50 ppm -, or +) and challenge (non-challenge, Cp EHE-NE18, or Cp WER-NE36). Oral administration of Eimeria oocysts (day 9) followed by inoculation with 1 mL 108 CFU Cp strains (day 14 and 15) were used to induce NE. Broiler performance was analyzed at day 10, 24, and 35. On day 16, intestinal lesion score and intestinal pH were evaluated and samples of cecal content were analyzed for bacterial counts and short-chain fatty acid concentrations (SCFA). Birds in both challenged groups showed higher feed conversion ratio (FCR), lower weight gain (P < 0.001), increased lesion scores in the jejunum (P < 0.01), and reduced pH in the ileum and cecum (P < 0.01), compared to the non-challenged birds. They also showed decreased numbers of Bacillus spp. (P < 0.001), and Ruminococcus spp. (P < 0.01) in the cecal content. On day 35, the NE36 challenged birds had a lower weight gain (P < 0.001) and higher FCR (P < 0.001) compared to the NE18 challenged birds. Interestingly, cecal Lactobacillus and lactate were increased by the NE challenge (P < 0.001), and to a greater extent in birds challenged with NE36 compared to the NE18 strain (P < 0.001). This study suggests that Cp strains varying in virulence produce different levels of disease in broiler chickens through modulating the gut environment, intestinal microbiota, and SCFA profile to different extents.

Energy efficiency and net energy prediction of feed in laying hens.

Using accurate nutrient values for ingredients is of vital importance for efficient diet formulation. The net energy (NE) system accounts for the real available amount of feedstuff energy for body maintenance and production as it considers energy dissipated as heat increment. The NE content of diets for pigs and broilers has been estimated from their nutrient contents. However, such estimates have not been made specifically for laying hens. This study reports the development of equations to predict NE for laying hens based on the chemical composition of 16 different diets meeting minimum nutrient specifications but varying in nutrient composition. Heat production and energy metabolism were measured in layers ranging from 32 to 62 weeks of age in closed-circuit calorimetry chambers with 8 replicates per diet in a randomized design. Each replicate consisted of a chamber with 3 layers that were adapted for 4 D to diets and chambers prior to measurement. The measurements included feed intake, metabolizable energy (ME) content, nitrogen balance, egg production, gas exchange, heat production, energy efficiency, and energy partition for a 3-D period. The average AME/GE and NE/AME ratios of the 16 diets were 77 and 74%, respectively. The latter ratio increased with energy efficiency (EE) content and decreased with CP content of diets. The results indicate that diet NE content can be predicted from AME, CP, and EE contents and the NE/AME ratio varied positively with EE and negatively with CP. A validation experiment with 2 diets fed to layers in calorimetry chambers confirmed the estimation from NE prediction equations. In conclusion, NE of diets can be predicted in laying hens from equations based on AME and CP and EE contents in laying hens being similar to those reported in broilers.

A mono-component microbial protease improves performance, net energy, and digestibility of amino acids and starch, and upregulates jejunal expression of genes responsible for peptide transport in broilers fed corn/wheat-based diets supplemented with xylanase and phytase.

A total of 90 male Ross 308 broiler chicks were used in a digestibility and performance bioassay to explore the effect of reduction in dietary protein and digestible amino acids and inclusion of an exogenous mono-component protease on amino acid digestibility, net energy, jejunal gene expression, and bird performance. Four dietary treatments were created by the supplementation, or not, of 2 control diets with a mono-component exogenous protease. The control diets were corn/wheat/soybean meal-based and were formulated to be either nutritionally adequate or reduced in protein and amino acids (around 3%). The 2 control diets were supplemented with xylanase and phytase (2000 FYT). Treatments were therefore arranged as a 2 × 2 factorial design. The reduction in diet nutrient density had no significant effect on various experimental outcomes (including bird performance, amino acid digestibility, and net energy [NE]) that were measured with the exception of a reduction in the expression of aminopeptidase N and glucose transporter 2. However, the addition of exogenous protease resulted in an increase in weight gain and a reduction in feed conversion ratio (around 4%; P < 0.05) and an increase in the digestibility of several amino acids (P < 0.05) and starch (P = 0.06). Protease addition also resulted in an increase in both apparent metabolizable energy (AME) (+73 kcal/kg; P < 0.05) and NE (+107 kcal/kg; P < 0.05). The addition of exogenous protease to the diet also increased the jejunal expression of genes responsible for peptide transport (PepT2; P < 0.01) and starch digestion (sucrase isomaltase; P = 0.06). These results confirm the efficacy of exogenous protease in broiler diets that contain both xylanase and phytase and suggest substantial beneficial effects that extend beyond protein and amino acid nutrition. The effect of exogenous protease on energy partitioning, starch digestibility and the efficiency of nitrogen cycling is an area for further study.

Dietary L-glutamine supplementation improves growth performance, gut morphology, and serum biochemical indices of broiler chickens during necrotic enteritis challenge.

Necrotic enteritis (NE) causes significant economic losses in the broiler chicken industry, especially in birds raised without in-feed antibiotics. L-glutamine (Gln) is an amino acid that may compensate for metabolic losses from infection and improve the intestinal development. This study investigated the effects of dietary Gln (10 g/kg) supplementation on growth performance, intestinal lesions, jejunum morphology, and serum biochemical indices of broiler chickens during NE challenge. The study employed a factorial arrangement of treatments with factors: NE challenge, no or yes; dietary Gln inclusion, 0 g/kg in starter (S), d 0 to 10, grower (G) d 10 to 24, and finisher (F) d 24 to 35; 10 g/kg in S, G, F, or 10 g/kg in S, G only. Each treatment was replicated in 6 floor pens with 17 birds per pen as the experimental unit for performance and 2 birds for other measurements. Challenge significantly reduced bird performance, increased incidence of intestinal lesions, and affected intestinal development and serum biochemical indices. Regardless of challenge, Gln supplementation increased gain (P < 0.05), feed intake (P < 0.05), and decreased FCR (P < 0.05) on d 24. On d 35, Gln improved gain (P < 0.05) and FCR (P < 0.001) whereas withdrawing Gln from finisher tended to diminish the beneficial effect on weight gain but not FCR. Dietary Gln reduced lesion scores in the jejunum (P < 0.01) and ileum (P < 0.01) in challenged birds. On d 16, Gln increased villus height to crypt depth ratio in unchallenged birds (P < 0.05) and reduced crypt depth of challenged birds on d 24 (P < 0.05). Regardless of challenge, supplementation with Gln reduced crypt depth on d 16 (P < 0.05), and increased villus height (P < 0.01) and the villus height to crypt depth ratio (P < 0.001) on d 24. Dietary Gln lowered serum uric acid level regardless of challenge (P < 0.05). The current study indicates that dietary Gln alleviates adverse effects of NE and may be useful in antibiotic-free diets.