Proteomic analyses on chicken breast meat with white striping myopathy.

White striping (WS) is an emerging myopathy that results in significant economic losses as high as $1 billion (combined with losses derived from other breast myopathies including woody breast and spaghetti meat) to the global poultry industry. White striping is detected as the occurrence of white lines on raw poultry meat. The exact etiologies for WS are still unclear. Proteomic analyses of co-expressed WS and woody breast phenotypes previously demonstrated dysfunctions in carbohydrate metabolism, protein synthesis, and calcium buffering capabilities in muscle cells. In this study, we conducted shotgun proteomics on chicken breast fillets exhibiting only WS that were collected at approximately 6 h postmortem. After determining WS severity, protein extractions were conducted from severe WS meat with no woody breast (WB) condition (n = 5) and normal non-affected (no WS) control meat (n = 5). Shotgun proteomics was conducted by Orbitrap Lumos, tandem mass tag (TMT) analysis. As results, 148 differentially abundant proteins (|fold change|>1.4; p-value < 0.05) were identified in the WS meats compared with controls. The significant canonical pathways included BAG2 signaling pathway, glycogen degradation II, isoleucine degradation I, aldosterone signaling in epithelial cells, and valine degradation I. The potential upstream regulators include LIPE, UCP1, ATP5IF1, and DMD. The results of this study provide additional insights into the cellular mechanisms on the WS myopathy and meat quality.

Effects of Methionine Supplementation Levels in Normal or Reduced Protein Diets on the Body Composition and Femur Bone Characteristics of Broilers Challenged with Coccidia.

This study investigated the effects of dietary methionine (Met) levels on the bone quality of broilers challenged with coccidia. A total of 600 fourteen-day-old male Cobb500 broilers were gavaged with mixed Eimeria spp. and randomly allocated into 10 treatment groups by a 2 × 5 factorial arrangement. Birds received normal protein diets (NCP) or reduced-protein diets (LCP), containing 2.8, 4.4, 6.0, 7.6, and 9.2 g/kg of Met. Data were analyzed via two-way ANOVA and orthogonal polynomial contrast. At 9 days post-inoculation (DPI), whole body bone mineral density (BMD) and bone mineral content (BMC) linearly decreased as Met levels increased (p < 0.05). For the femoral metaphysis bone quality at 9 DPI, BMD linearly decreased, and porosity linearly increased as Met levels increased (p < 0.05) in the cortical bone. The increased Met levels linearly improved trabecular bone quality in LCP groups (p < 0.05) while not in NCP groups. For the femoral diaphysis cortical bone at 6 DPI, LCP groups had higher BMD and BMC than NCP groups (p < 0.05). Bone volume linearly increased as Met levels increased in LCP groups (p < 0.05) while not in NCP groups. In summary, the results suggested that increased Met levels decreased the cortical bone quality. However, in the context of reduced-protein diets, the increased Met levels improved trabecular bone quality.

Reduced ribonucleotide reductase RRM2 subunit expression increases DNA damage and mitochondria dysfunction in woody breast chickens.

OBJECTIVE: The aim of this study was to investigate the roles of ribonucleotide reductase subunit M2 (RRM2; subunit of ribonucleotide reductase) in severe woody breast (WB) and normal breast muscles. ANIMALS: 40 8-week-old male Ross-708 broiler chickens. METHODS: Quantitative PCR was performed to determine gene expression, and commercial ELISA/assay kits were used to obtain several enzymatic activities. RESULTS: Results showed that RRM2 activity (P = .0002) and RRM2 (P = .05) and hydroxymethylbilane synthase expression (impaired oxygen transport and metabolism, P = .002) were reduced in WB, while caveolin-3 (defected membrane integrity, P = .09), endoglin (increased fibrosis, P = .06), and secreted protein acidic rich in cysteine (metabolic dysregulation, P = .09) expression tended to increase in WB. WB tended to have increased levels of homocysteine (P = .06), aspartate aminotransferase mitochondria (P = .02), pyruvate kinase (P = .04), DNA damage (P = .06), creatine kinase (P = .05), and triglyceride (P = .002) but decreased ATPase activity (P = .01), all indicating mitochondria dysfunction and tissue damage. CLINICAL RELEVANCE: In this study, differences in various enzyme activities and increased DNA damage suggest that RRM2-mediated mitochondrial abnormalities may play a role in WB myopathy.

Effects of phytase supplementation on broilers fed with calcium and phosphorus-reduced diets, challenged with Eimeria maxima and Eimeria acervulina: influence on growth performance, body composition, bone health, and intestinal integrity.

An experiment was conducted to evaluate the effects of phytase in calcium (Ca) and available phosphorous (avP)-reduced diet on growth performance, body composition, bone health, and intestinal integrity of broilers challenged with Eimeria maxima and Eimeria acervulina. A total of 672 14-day-old male broilers were allocated to a 2 × 4 factorial arrangement with 6 replicates per treatment and 14 birds per replicate. Two factors were Eimeria challenge and 4 dietary treatments: 1) a positive control (PC; 0.84% Ca and 0.42% avP); 2) a negative control (NC; 0.74% Ca and 0.27% avP); 3) NC + 500 FTU/Kg of phytase (NC + 500PHY); and 4) NC + 1,500 FTU/Kg of phytase (NC + 1500PHY). On d 14, birds in the Eimeria-challenged groups received a solution containing 15,000 sporulated oocysts of E. maxima and 75,000 sporulated oocysts of E. acervulina via oral gavage. At 5 d postinoculation (DPI), the challenged birds showed a higher (P < 0.01) FITC-d level than the unchallenged birds. While the permeability of the NC group did not differ from the PC group, the phytase supplementation groups (NC + 500PHY and NC + 1500PHY) showed lower (P < 0.05) serum FITC-d levels compared to the NC group. Interaction effects (P < 0.05) of Eimeria challenge and dietary treatments on feed intake (FI), mucin-2 (MUC2) gene expression, bone ash concentration, and mineral apposition rate (MAR) were observed. On 0 to 6 and 0 to 9 DPI, Eimeria challenge decreased (P < 0.01) body weight (BW), body weight gain (BWG), FI, bone mineral density (BMD), bone mineral content (BMC), bone area, fat free bone weight (FFBW), bone ash weight, bone ash percentage and bone ash concentration; and it showed a higher FCR (P < 0.01) compared to the unchallenged group. The reduction Ca and avP in the diet (NC) did not exert adverse effects on all parameters in birds, and supplementing phytase at levels of 500 or 1,500 FTU/Kg improved body composition, bone mineralization, and intestinal permeability, with the higher dose of 1,500 FTU/Kg showing more pronounced enhancements. There was an observed increase in FI (P < 0.01) when phytase was supplemented at 1,500 FTU/Kg during 0 to 6 DPI. In conclusion, results from the current study suggest that dietary nutrients, such as Ca and avP, can be moderately reduced with the supplementation of phytase, particularly in birds infected with Eimeria spp., which has the potential to save feed cost without compromising growth performance, bone health, and intestinal integrity of broilers.

Water properties in intact wooden breast fillets during refrigerated storage.

The wooden breast (WB) condition notably alters moisture content and water holding capacity (WHC) in broiler breast fillets. The purpose of this study was to investigate water properties during refrigerated storage from 4 h to 168 h postmortem using time domain nuclear magnetic resonance (TD-NMR). Water properties measured included mobility (T), proportion (P), and abundance per 100 g of meat (A). Changes in meat quality indicators including compression force, color, pH, cumulative purge loss, and proximate composition were also measured. Compression force and energy of the WB fillets were higher than normal fillets (P < 0.05). Slopes of changes in lightness of the WB and normal fillets were different in skin and bone side (P < 0.05). The slope of the purge loss from the WB fillets was higher than the normal fillets (P < 0.05). Time domain nuclear magnetic resonance analysis showed 4 water populations in intact broiler fillets with transverse relaxation time (T2) constants at approximately 4 to 5 milliseconds (ms) (designated as 2b, corresponding to hydration water or bound water), 40 to 60 ms (designated as 21, corresponding to intra-myofibrillar water or immobilized water), 80 to 210 ms (designated as 22a, corresponding to extra-myofibrillar water or free water with lower mobility) and 210 to 500 ms (designated as 22b, corresponding to extra-myofibrillar water or free water with higher mobility) during early postmortem storage (between 4 h and 72 h postmortem) and only 3 populations (2b, 21, and 22a) after 72 h postmortem. There were interaction effects (P < 0.05) between storage time and WB condition for all water properties except T2b, A2b/100 g, and T22b. The linear change of T21, P21, A21/100 g, T22a, A22a/100 g, P22b, and A22b/100 g in stored WB samples were different from the normal fillets (P < 0.05). During storage, P21 and A21/100 g of the WB fillets exhibited faster linear increases than those of the normal fillets, whereas T21 and T22a of the normal fillets and A22a/100 g, P22b, and A22b/100 g of the WB fillets showed faster linear decreases (P < 0.05). Our data demonstrate that the WB condition affects changes in water properties in broiler fillets during postmortem refrigerated storage.

In vitro and in vivo evaluation of tannic acid as an antibacterial agent in broilers infected with Salmonella Typhimurium.

This study was conducted to evaluate tannic acid (TA) as an antibacterial agent against Salmonella Typhimurium in in vitro and in vivo chicken models. The TA formed an inhibitory zone against Salmonella enterica serotypes including S. Typhimurium, S. Enteritidis, and S. Infantis. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of TA against Salmonella Typhimurium nalidixic acid resistant strain (STNR) were determined as 40 and 700 µg/mL, respectively. Sublethal doses of TA (5, 10, and 20 µg/mL) restricted swimming and swarming motility and biofilm formation of STNR compared to the control group (0 µg/mL) (P < 0.05). The TA-bovine serum albumin (BSA) complex formed at simulated gastric pH (pH 3.75) was hydrolyzed at pH 6.75 and 7.25 (P < 0.05), and the hydrolysis of the TA-BSA complex was stronger at pH 7.25 compared to the pH 6.75 (P < 0.05). The inhibitory zone of the TA-BSA complex against STNR at pH 6.75 was lower than TA without BSA at 30 and 60 min (P < 0.05), but not at 120 min (P > 0.1). The inhibitory zone of the TA-BSA complex against STNR at pH 7.25 was not decreased at 0, 30, and 60 min compared to TA without BSA (P > 0.1). The recovery rate of TA was 83, 54.8, 10.5, and 19.6% in the gizzard, jejunum, ileum, and ceca, respectively, in broiler chickens. The STNR-infected broilers fed 0.25 g/kg of TA had significantly lower unweighted beta diversity distance compared to the sham-challenged control (SCC) and challenged controlled (CC) group on D 21. TA supplementation linearly (P < 0.05) and quadratically (tendency; P = 0.071) reduced relative abundance of the family Peptostreptococcaceae in broilers infected with STNR on D 7. TA supplementation linearly (P < 0.05) and quadratically (tendency; P = 0.06) increased the relative abundance of the family Erysipelotrichaceae in broilers infected with STNR on D 21. Therefore, TA has potential to be used as an antibacterial agent against the S. Typhimurium infection in broilers.

Effects of Eimeria maxima infection doses on growth performance and gut health in dual-infection model of necrotic enteritis in broiler chickens.

The objective of this study was to investigate the effects of the different doses of Eimeria maxima (EM) oocysts on growth performance and intestinal health in broiler chickens challenged with a dual infection model of necrotic enteritis (NE) using EM and NetB+ Clostridium perfringens (CP). A total of 432 fourteen-d-old male Cobb 500 broiler chickens were divided into 6 groups with 6 replicates each. The six different groups were as follows: Control, non-challenged; T0+, challenged with CP at 1 × 109 colony forming unit; T5K+, T0+ + 5,000 EM oocysts; T10K+, T0+ + 10,000 EM oocysts; T20K+; T0+ + 20,000 EM oocysts; and T40K+; T0+ + 40,000 EM oocysts. The challenge groups were orally inoculated with EM strain 41A on d 14, followed by NetB+ CP strain Del-1 on 4 days post inoculation (dpi). Increasing EM oocysts decreased d 21 body weight, body weight gain, feed intake (linear and quadratic, p < 0.001), and feed efficiency (linear, p < 0.001) from 0 to 7 dpi. Increasing EM oocysts increased jejunal NE lesion score and intestinal permeability on 5, 6, and 7 dpi (linear, p < 0.05). On 7 dpi, increasing the infection doses of EM oocysts increased jejunal CP colony counts (linear, p < 0.05) and increased fecal EM oocyst output (linear and quadratic, p < 0.001). Furthermore, increasing the infection doses of EM oocysts decreased the villus height to crypt depth ratios and the goblet cell counts (linear, p < 0.05) on 6 dpi. Increasing EM oocysts downregulated the expression of MUC2, B0AT, B0,+AT, PepT1, GLUT2, AvBD3 and 9, LEAP2, and TLR4, while upregulating CLDN1, CATHL3, IL-1ß, IFN-γ, TNFSF15, TNF-α, IL-10, and Gam56 and 82 on 6 dpi (linear, p < 0.05). Additionally, increasing EM oocysts decreased Pielou's evenness and Shannon's entropy (linear, p < 0.01). In conclusion, increasing the infection doses of EM significantly aggravated the severity of NE and exerted negative impact on intestinal health from 5 to 7 dpi.

Effects of Different Eimeria Inoculation Doses on Growth Performance, Daily Feed Intake, Gut Health, Gut Microbiota, Foot Pad Dermatitis, and Eimeria Gene Expression in Broilers Raised in Floor Pens for 35 Days.

The study was conducted to investigate the effects of different Eimeria inoculation doses on the growth performance, gut ecosystem, and body composition of broilers in floor pens for 35 days. A total of 750 15-day-old broilers were allocated to five experimental groups with six replicate pens. The five experimental groups included unchallenged control (CON); Eimeria dose 1 (ED1): E. acervulina: 31,250/E. maxima: 6250/E. tenella: 6250; Eimeria dose 2 (ED2): E. acervulina: 62,500/E. maxima: 12,500/E. tenella: 12,500; Eimeria dose 3 (ED3): E. acervulina: 125,000/E. maxima: 25,000/E. tenella: 25,000; and Eimeria dose 4 (ED4): E. acervulina: 250,000/E. maxima: 50,000/E. tenella: 50,000. On D 21, BW were linearly reduced by increased Eimeria inoculation doses (p < 0.01). On D 35, the Eimeria challenge groups had significantly lower BW compared to the CON group. Increased Eimeria inoculation doses linearly decreased crude fat (CF) (p < 0.01) on D 21. Increased Eimeria inoculation doses tended to increase the relative abundance of the phylum Proteobacteria (p = 0.098) on D 21. On D 35, lean:fat was linearly reduced by increased Eimeria inoculation doses (p < 0.05). Eimeria infection negatively influenced growth performance and gut health in broilers in the acute phase, and the negative effects were prolonged to D 35 in floor pen conditions.

Nutritional Strategies to Improve Meat Quality and Composition in the Challenging Conditions of Broiler Production: A Review.

Poultry meat is becoming one of the most important animal protein sources for human beings in terms of health benefits, cost, and production efficiency. Effective genetic selection and nutritional programs have dramatically increased meat yield and broiler production efficiency. However, modern practices in broiler production result in unfavorable meat quality and body composition due to a diverse range of challenging conditions, including bacterial and parasitic infection, heat stress, and the consumption of mycotoxin and oxidized oils. Numerous studies have demonstrated that appropriate nutritional interventions have improved the meat quality and body composition of broiler chickens. Modulating nutritional composition [e.g., energy and crude protein (CP) levels] and amino acids (AA) levels has altered the meat quality and body composition of broiler chickens. The supplementation of bioactive compounds, such as vitamins, probiotics, prebiotics, exogenous enzymes, plant polyphenol compounds, and organic acids, has improved meat quality and changed the body composition of broiler chickens.

Effects of levels of methionine supplementations in forms of L- or DL-methionine on the performance, intestinal development, immune response, and antioxidant system in broilers challenged with Eimeria spp.

The study was conducted to investigate the effects of 2 isoforms of methionine on growth performance and intestinal health induced by methionine (Met) deficiency and Eimeria infection in broilers. A total of 720 one-day old male chicks (Cobb500) were randomly allocated to 10 groups in a 2 × 5 factorial arrangement (6 reps/group, 12 birds/cage) with diets and Eimeria challenge as the main factors. Hundred percent DL-Met, 100% L-Met, 80% DL-Met, and 80% L-Met diets were formulated to meet approximately 100 or 80% of the total sulfur amino acid (TSAA) requirement with DL-Met or L-Met as Met supplementation sources. The 60% TSAA basal diet (60% Met) was formulated without Met supplementation. At d14, the challenge groups were gavaged with mixed Eimeria spp. Growth performance was recorded on d7, 14, 20 (6-day postinfection [DPI]), and 26 (12 DPI). The gut permeability was measured on 5 and 11 DPI. Antioxidant status and gene expression of immune cytokines and tight junction proteins were measured on 6 and 12 DPI. Data were analyzed by 1-way and 2-way ANOVA before and after the challenge, respectively. Orthogonal polynomial contrasts were used for post hoc comparison. Overall, the Eimeria challenge and 60% Met diet significantly reduced growth performance, antioxidant status, and mRNA expression of tight junction genes and immune cytokines. For other Met treatments, the L-Met groups had significantly higher BWG and lower FCR than the DL-Met group from d 1 to 20. The L-Met groups had less gut permeability than the DL-Met groups on 5 DPI. Compared to the 80% Met groups, the 100% Met groups reduced gut permeability. At 6 DPI, the 80% Met groups showed higher ZO1 expression than the 100% Met groups. The challenge groups had higher Muc2 expression and GSH/GSSG compared to the nonchallenge groups, and SOD activity was lower in the L-Met groups compared to the DL-Met groups at 6 DPI. The 100% Met groups had higher GPx activity than the 80% Met groups at 12 DPI. In conclusion, during coccidiosis, the 100% Met groups had better gut integrity and antioxidant status. Met supplementation in the form of L-Met improved growth performance in the starter phase and gut permeability in the challenge phase.

Reduced bone formation and increased bone resorption drive bone loss in Eimeria infected broilers.

Coccidiosis is an economically significant disease in the global poultry industry, but little is known about the mechanisms of bone defects caused by coccidiosis; thus, the study focused on effects of coccidiosis on the bone homeostasis of young broiler chickens. A total of 480 male Cobb500 broilers were randomly allocated into four treatment groups, including an uninfected control consuming diet ad libitum, two infected groups were orally gavaged with two different concentrations of sporulated Eimeria oocysts, and an uninfected pair-fed group fed the same amount of feed as the high Eimeria-infected group consumed. Growth performance and feed intake were recorded, and samples were collected on 6 days post infection. Results indicated that coccidiosis increased systemic oxidative status and elevated immune response in bone marrow, suppressing bone growth rate (P < 0.05) and increasing bone resorption (P < 0.05) which led to lower bone mineral density (P < 0.05) and mineral content (P < 0.05) under Eimeria infection. With the same amount of feed intake, the uninfected pair-fed group showed a distinguished bone formation rate and bone resorption level compared with the Eimeria infected groups. In conclusion, inflammatory immune response and oxidative stress in broilers after Eimeria infection were closely associated with altered bone homeostasis, highlighting the role of inflammation and oxidative stress in broiler bone homeostasis during coccidiosis.

Comparative effects of dietary methionine and cysteine supplementation on redox status and intestinal integrity in immunologically challenged-weaned pigs.

Sulfur-containing amino acids such as methionine and cysteine play critical roles in immune system and redox status. A body of evidence shows that metabolic aspects of supplemented Met and Cys may differ in the body. Therefore, the study aimed to investigate the effects of dietary Met and Cys supplementation in immunologically challenged weaned pigs. Forty weaned piglets (6.5 ± 0.3 kg) were randomly allocated to five treatment groups. The treatment included: (1) sham-challenged control (SCC), (2) challenged control (CC), (3) MET (CC + 0.1% DL-Met), (4) CYS (CC + 0.1% L-Cys), and (5) MET + CYS (CC + 0.1% DL-Met + 0.1% L-Cys). On day 7, all pigs were intramuscularly injected with either Escherichia coli O55:B5 lipopolysaccharides (LPS) or phosphate-buffered saline. Blood, liver, and jejunum samples were analyzed for immune response and redox status. The CC group had lower (P < 0.05) villus surface area and higher (P < 0.05) flux of 4-kDa fluorescein isothiocyanate dextran (FD4) than the SCC group. A lower (P < 0.05) glutathione (GSH) concentration was observed in the jejunum of pigs in the CC group than those in the SCC group. Dietary Cys supplementation increased (P < 0.05) villus surface area, GSH levels, and reduced (P < 0.05) the flux of FD4 in the jejunum of LPS-challenged pigs. Dietary Met supplementation enhanced (P < 0.05) hepatic GSH content. Pigs challenged with LPS in the MET group had lower serum IL-8 concentration than those in the CC group. There was a Met × Cys interaction (P < 0.05) in serum IL-4 and IL-8 concentrations, and Trolox equivalent antioxidant capacity. Dietary L-Cys supplementation restored intestinal integrity and GSH levels that were damaged by lipopolysaccharides administration. Dietary DL-Met supplementation improved hepatic GSH and reduced systemic inflammatory response, but antagonistic interaction with dietary L-Cys supplementation was observed in the inflammatory response and redox status.

Interactions of Microbiota and Mucosal Immunity in the Ceca of Broiler Chickens Infected with Eimeria tenella.

The purpose of the study was to investigate the effects of Eimeria tenella infection on the cecal microbiome, the protein concentration of cecal content, cecal mucosal immunity, and serum endotoxin levels in broilers. Three hundred sixty 14-day-old broilers were allocated to five infection doses with six replicates. The five infection doses were: ID0: 0, ID1: 6250, ID2: 12,500, ID3: 25,000, and ID4: 50,000 Eimeria tenella oocysts. Eimeria tenella infection significantly increased the relative abundance of the phylum Proteobacteria, which includes diverse pathogenic bacteria, and significantly decreased the relative abundance of the phylum Firmicutes. Protein concentration of the cecal content was linearly increased (p < 0.05), and the concentration of secretory immunoglobulin A (sIgA) in the cecal content was linearly decreased by Eimeria tenella infection (p < 0.05). Goblet cell density was linearly reduced in the ceca by Eimeria tenella infection (p < 0.05). Eimeria tenella infection tended to linearly decrease the relative mRNA expression of antimicrobial peptide genes such as avian beta-defensin 9 (AvBD9; p = 0.10) and liver-expressed antimicrobial peptide 2 (LEAP2; p = 0.08) in the cecal tissue. Therefore, Eimeria tenella infection negatively modulated cecal microbiota via impairing cecal mucosal immunity and increasing protein concentration in the cecal content in broilers.

Effects of supplemental tannic acid on growth performance, gut health, microbiota, and fat accumulation and optimal dosages of tannic acid in broilers.

This study was conducted to investigate the effects of different dosages of tannic acid (TA) on growth performance, nutrient digestibility, gut health, immune system, oxidative status, microbial composition, volatile fatty acids (VFA), bone mineral density, and fat digestion and accumulation in broilers and to find optimal dosages of TA for efficient growth and gut health in broilers. A total of 320 male Cobb500 broilers were randomly distributed to 4 treatments with 8 replicates including 1) tannic acid 0 (TA0): basal diet without TA; 2) tannic acid 0.5 (TA0.5): basal diet with 0.5 g/kg TA; 3) tannic acid 1.5 (TA1.5); and 4) tannic acid 2.5 (TA2.5). Supplemental TA at levels greater than 972 mg/kg tended to reduce BW on D 21 (p = 0.05). The TA2.5 had significantly lower apparent ileal digestibility (AID) of crude protein compared to the TA0 group. The AID of ether extract tended to be reduced by TA at levels greater than 525 mg/kg (p = 0.08). The jejunal lipase activities tended to be reduced by TA at levels less than 595.3 mg/kg (p = 0.09). TA linearly decreased goblet cell density in the crypts of the jejunum (p < 0.05) and reduced mRNA expression of mucin two at levels less than 784.9 mg/kg and zonula occludens two at levels less than 892.6 mg/kg (p < 0.05). The TA0.5 group had higher activities of liver superoxide dismutase compared to the TA0 group (p < 0.05). Bone mineral density and contents tended to be linearly decreased by TA (p = 0.05), and the ratio of lean to fat was linearly decreased (p < 0.01). Total cecal VFA production tended to be linearly reduced by TA at levels greater than 850.9 mg/kg (p = 0.07). Supplemental TA tended to increase the relative abundance of the phylum Bacteroidetes (p = 0.1) and decrease the relative abundance of the phylum Proteobacteria (p = 0.1). The relative abundance of the family Rikenellaceae was the lowest at 500 mg/kg TA, and the relative abundance of the family Bacillaceae was the highest at 1,045 mg/kg TA. Collectively, these results indicate that the optimum level of supplemental TA would range between 500 and 900 mg/kg; this range of TA supplementation would improve gut health without negatively affecting growth performance in broilers under antibiotic-free conditions.

Antimicrobial and immunomodulatory effects of tannic acid supplementation in broilers infected with Salmonella Typhimurium.

Infection by Salmonella Typhimurium, a food-borne pathogen, can reduce the poultry production efficiency. The objective of this study was to investigate the effects of tannic acid (TA) supplementation on growth performance, Salmonella colonization, gut barrier integrity, serum endotoxin levels, antioxidant capacity, gut health, and immune function in broilers infected with the Salmonella enterica serovar Typhimurium nalidixic acid resistant strain (STNR). A total of 546 one-day-old broilers were arbitrarily allocated into 6 treatments including 1) Sham-challenged control (SCC; birds fed a basal diet and administrated peptone water); 2) Challenged control (CC; birds fed a basal diet and inoculated with 108 STNR); 3) Tannic acid 0.25 (TA0.25; CC + 0.25 g/kg TA); 4) TA0.5 (CC + 0.5 g/kg TA); 5) TA1 (CC + 1 g/kg TA); and 6) TA2 (CC + 2 g/kg TA). On D 7, supplemental TA linearly reduced STNR colonization in the ceca (P < 0.01), and TA1 and TA2 group had significantly lower reduced STNR colonization in the ceca (P < 0.01). On D 7 to 21, average daily gain tended to be linearly increased by supplemental TA (P = 0.097). The serum endotoxin levels were quadratically decreased by supplemental TA on D 21 (P < 0.05). Supplemental TA quadratically increased ileal villus height (VH; P < 0.05), and the TA0.25 group had higher ileal VH compared to the CC group (P < 0.05). Supplemental TA linearly increased percentage of peripheral blood CD8+ T cells on D 18 (P < 0.01). The TA0.5 group had significantly lower lymphocyte numbers compared to the CC groups (P < 0.05). The abundance of monocytes linearly increased with TA supplementation (P < 0.01). Therefore, broilers fed TA had reduced STNR colonization, increased growth performance, decreased serum endotoxin levels, enhanced gut health in the broilers, and stimulated the immune system in broilers infected with STNR. Supplementation of TA (1-2 g/kg) enhanced growth performance and gut health via antimicrobial and immunostimulatory effects in broilers infected with STNR.

Application of Organic Acids and Essential Oils as Alternatives to Antibiotic Growth Promoters in Broiler Chickens.

This study was conducted to evaluate the effects of OAs and EOs on growth performance, serum biochemistry, antioxidant enzyme activities, intestinal morphology, and digestive enzyme activities to replace AGP in broilers. Six hundred one-day-old broilers were allotted to five treatments with six replicates: (1) negative control (NC; basal diet); (2) positive control (PC; NC + 50 mg/kg bacitracin methylene disalicylate); (3) organic acids (OA; NC + 2000 mg/kg OA); (4) essential oils (EO; NC + 300 mg/kg EO); and (5) OA + EO (NC + 2000 mg/kg OA + 300 mg/kg EO). In the starter phase, the PC, EO, and OA + EO groups had a significantly lower feed conversion ratio (FCR) compared to the NC group. While the final body weight (BW) of broilers fed OAs was similar compared to broilers fed PC (p > 0.1), the FCR of the OA group tended to be lower than the PC group on D 42 (p = 0.074). The OA group had the higher serum GLOB:ALB (albumin) and ileal villus height and crypt depth (VH:CD) ratios compared to the EO group. Thus, the supplementation of EOs and OAs could substitute AGP in the starter and finisher phase, respectively.

Effects of Tannic Acid Supplementation on Growth Performance, Oocyst Shedding, and Gut Health of in Broilers Infected with Eimeria Maxima.

The purpose of this study was to evaluate effects of tannic acid (TA) on growth performance, fecal moisture content, oocyst shedding, gut permeability, lesion score, intestinal morphology, apparent ileal digestibility, and the antioxidant and immune system of broilers infected with Eimeria maxima. A total of 420 one-day-old broilers were distributed to five treatments with seven replicates of 12 birds. The five treatments were the (1) sham-challenged control (SCC; birds fed a control diet and administrated with PBS); (2) challenged control (CC; birds fed a control diet and inoculated with E. maxima); (3) tannic acid 0.5 (TA0.5; CC + 500 mg/kg TA); (4) tannic acid 2.75 (TA2.75; CC + 2750 mg/kg TA); and (5) tannic acid 5 (TA5; CC + 5000 mg/kg TA). The TA2.75 group had significantly lower gut permeability compared to the CC group at 5 days post-infection (dpi). Supplementation of TA linearly reduced oocyst shedding of E. maxima at 7 to 9 dpi (p < 0.05). At 13 dpi, the TA2.75 group had significantly greater apparent ileal digestibility (AID) of dry matter (DM) and organic matter (OM) compared to the CC group. At 13 dpi, supplementation of TA linearly increased jejunal villus height (VH). Thus, this study showed that supplementation of TA at levels of 500 to 2750 mg/kg has the potential to be an anti-coccidial agent against E. maxima in broilers.

Effects of tannic acid supplementation on growth performance, gut health, and meat production and quality of broiler chickens raised in floor pens for 42 days.

A study was conducted to investigate the effects of tannic acid (TA) supplementation on growth performance, gut health, antioxidant capacity, gut microbiota, and meat yield and quality in broilers raised for 42 days. A total of 700 one-day-old male broiler chickens (Cobb500) were allocated into 5 treatments with 7 replicates of 20 birds per pen. There were five treatments: 1) tannic acid 0 (TA0: basal diet without TA); 2) tannic acid 0.25 (TA0.25: basal diet+0.25 g/kg TA); 3) tannic acid 0.5 (TA0.5: basal diet+0.5 g/kg TA); 4) tannic acid 1 (TA1: basal diet+1 g/kg TA); and 5) tannic acid 2 (TA2: basal diet+2 g/kg TA). The dietary phases included starter (D 0 to 18; crumble feed), grower (D 18 to 28; pellet feed), and finisher (D 28 to 42; pellet feed). On D 18, the supplementation of TA linearly reduced body weight (BW) and average daily feed intake (ADFI) (p < 0.05), and on D 28, the supplementation of TA linearly reduced BW, average daily gain (ADG), and feed conversion ratio (FCR) (p < 0.05). Relative mRNA expression of genes related to mucin production (MUC2), tight junction proteins (CLDN2 and JAM2), and nutrient transporters (B0AT1 and SGLT1) was linearly increased by the supplementation of TA (p < 0.05). The supplementation of TA tended to linearly increase the relative abundance of the family Enterobacteriaceae (p = 0.08) and quadratically increased the relative abundance of the families Lachnospiraceae and Ruminococcaceae in the cecal microbial communities (p < 0.05). On D 36, the ratio of the phyla Firmicutes and Bacteroidetes was quadratically reduced by the supplementation of TA (p < 0.05). On D 42, bone mineral density and the lean to fat ratio were linearly decreased by the supplementation of TA (p < 0.05). On D 43, total chilled carcass weight was linearly reduced (p < 0.05), and proportion of leg weight was increased by supplementation of TA (p < 0.05). The supplementation of TA linearly reduced pH of the breast meat (p < 0.05) and linearly increased redness (a*) (p < 0.05). Although the supplementation of TA positively influenced gut health and gut microbiota in the starter/grower phases, it negatively affected overall growth performance, bone health, and meat production in broilers on D 42.

Nutrient profile and effects of carinata meal as alternative feed ingredient on broiler performance, tight junction gene expression and intestinal morphology.

Two studies were conducted to establish carinata meal as a partial replacement of conventional protein sources. Study I was conducted to determine the nutrient profile, nitrogen-corrected true metabolizable energy (TMEn), and amino acid (AA) digestibility of 2 groups: low glucosinolate carinata meal (LGCM) and high glucosinolate carinata meal (HGCM) using rooster assays. The LGCM contained 28 µmol/g glucosinolate, 11.5% moisture, 39.2% crude protein (CP), whereas the HGCM had 100 µmol/g glucosinolate, 10.1% moisture, 39.5% CP on as is basis. The precision-fed rooster assays were conducted to determine TMEn and AA digestibility. The TMEn levels of LGCM and HGCM were 1,814 and 1,690 kcal/kg on as is basis, respectively. Standardized digestibility for lysine, methionine, cysteine, threonine, and valine were 72, 88, 69, 75, and 79% for LGCM and 80, 89, 71, 76, and 80% for HGCM, respectively. Based on the nutrient profiles from study I, study II was conducted to evaluate the effects of LGCM and HGCM in broilers. A total of 504 one-day-old Cobb500 male broiler chickens were randomly divided into 42 battery cages with 6 replicates of 12 birds per cage. The seven dietary treatments were control diet, 3 inclusion levels of LGCM (4, 8, and 12%), and 3 of HGCM (4, 8, and12%) in a corn-SBM based diet fed for 21 d. No significant differences in BW, BWG, and FI were observed except for significantly lower BWG in 12% HGCM group compared to control for 14-21 days (P < 0.05). The FCR for 12% HGCM increased significantly compared to 4 and 8% of both LGCM and HGCM groups during wk 3 (14-21 d). Based on these studies, carinata meal could be recommended to partially replace conventional feed ingredients at a rate of 12% when LGCM is used and 8% when HGCM is used with no deleterious effects on growth performance, gut histology, and tight junction proteins.

Effects of Eimeria tenella Infection on Key Parameters for Feed Efficiency in Broiler Chickens.

The purpose of the study was to investigate effects of different inoculation dosages of E. tenella on growth performance, gastrointestinal permeability, oocyst shedding, intestinal morphology, fecal consistency, ileal apparent digestibility, antioxidant capacity, and cecal VFA profile in broiler chickens. Five different dosages (T0: 0, T1: 6250, T2: 12,500, T3: 25,000, and T4: 50,000) of E. tenella oocysts were inoculated via oral gavage to fourteen-day-old broilers. Inoculation of E. tenella linearly increased FCR (p < 0.05), and feed intake was quadratically increased on 6 days post-infection (dpi; p = 0.08) and 7 dpi (p = 0.09). Cecal lesion score of each treatment was T0: 0; T1: 0.39 ± 0.14; T2: 0.93 ± 0.21; T3: 1.25 ± 0.16; and T4: 1.58 ± 0.2. Cecal total VFA production was linearly reduced due to E. tenella infection on 6 dpi (p < 0.01). E. tenella infection deepened cecal crypts depth on 6 dpi (CD; p < 0.05). Gastrointestinal permeability tended to be linearly increased (p = 0.07). E. tenella infection tended to linearly reduce duodenal VH (p = 0.1) and jejunal VH on 9 dpi (p = 0.09). Different dosages of E. tenella modulated the tendency of fecal moisture content and oocyst shedding. Therefore, E. tenella infection impaired feed efficiency and small intestinal health mainly by reducing cecal VFA production and deepening cecal CD in broilers.