Possible Molecular Mechanisms by Which an Essential Oil Blend from Star Anise, Rosemary, Thyme, and Oregano and Saponins Increase the Performance and Ileal Protein Digestibility of Growing Broilers

Transcriptomic and metabolomic-based revelation of the effect of fresh corn extract on meat quality of Jingyuan chicken

To investigate the effect of fresh corn extract (FCE) on chicken meat quality, 135-day-old Jingyuan chicken hens were fed diets containing different doses of FCE (CON, 0.3% FCE, 0.6% FCE and 0.9% FCE) until 180 day-old in this study. Meat performance measurements showed that the 0.6% FCE group of Jingyuan chickens had higher intramuscular fat (IMF), pressing loss (PL), amino acid and fatty acid contents (P < 0.05). Their breasts were collected for transcriptomic and metabolomic analyses (n=8), and 210 Differentially expressed genes (DEGs) and 29 Differentially expressed genes (DEMs) were obtained. Gene Ontology (GO) analyses of DEGs indicate multiple entries involved in IMF synthesis such as skeletal system development and cellular response to amino acid stimulation. Kyoto Encyclopedia of Genes and Genomes (GSEA-KEGG) analysis identified sphingolipid_metabolism and multiple genes affecting IMF deposition including SPHK1, CERS1, CERS6, GLB1L, SGMS2, UGT8, and UGCG. KEGG and metabolite correlation analyses of DEMs identified Aspartate, PI 38:5; PI(18:1/20:4), PI 36:3; PI(18:1/18:2), PI 36:2; PI(18:0/18:2), and PI 34:1; PI(16:0/18:1) as the likely major influences on IMF deposition in the DEMs. Correlation analysis revealed that shear force (SF) was significantly and positively correlated with Aspartate and CERS6; PL was significantly and positively correlated with SPHK1 and UGCG (P < 0.05). IMF was significantly and positively correlated with PI 34:1; PI (16:0/18:1), SPHK1 and UGCG; and flesh colour yellowness b* was significantly and positively correlated with SGMS2 (P < 0.05). The above results indicate that feeding a basal diet containing 0.6% FCE can improve the meat quality of Jingyuan chicken, which provides a theoretical basis for improving the meat quality of Jingyuan chicken.

Integrated transcriptome and microbiome analyses of residual feed intake in ducks during high production period

Residual feed intake (RFI) is a crucial parameter for assessing the feeding efficiency of poultry. Minimizing RFI can enhance feed utilization and reduce costs. In this study, 315 healthy female ducks were individually housed in cages. Growth performance was monitored during the high laying period, from 290 to 325 d of age. The cecal transcriptome and microbiome of 12 ducks with high RFI and 12 with low residual feed intake (LRFI) were analyzed. Regarding growth performance, the LRFI group exhibited significantly lower RFI, feed conversion ratio (FCR), and feed intake (Fi) compared to the HRFI group (p < 0.01). However, there were no significant differences observed in body weight (BW), body weight gain (BWG), and egg mass (EML) between the groups (p > 0.05). Microbiome analysis demonstrated that RFI impacted gut microbial abundance, particularly affecting metabolism and disease-related microorganisms such as Romboutsia, Enterococcus, and Megamonas funiformis. Transcriptome analysis revealed that varying RFI changed the expression of genes related to glucose metabolism and lipid metabolism, including APOA1, G6PC1, PCK1, and PLIN1. The integrated analysis indicated that host genes were closely linked to the microbiota and primarily function in lipid metabolism, which may enhance feeding efficiency by influencing metabolism and maintaining gut homeostasis.

In ovo delivery of oregano essential oil activated xenobiotic detoxification and lipid metabolism at hatch in broiler chickens

In ovo interventions are used to improve embryonic development and robustness of chicks. The objective of this study was to identify the optimal dose for in ovo delivery of oregano essential oil (OEO), and to investigate metabolic impacts. Broiler chickens Ross 308 fertile eggs were injected with 7 levels of OEO (0, 5, 10, 20, 30, 40, and 50 µL) into the amniotic fluid at embryonic d 17.5 (E17.5) (n = 48). Chick quality was measured by navel score (P < 0.05) and/or hatchability rates (P < 0.01) were significantly decreased at doses at or above 10 or 20 µL/egg, respectively, indicating potential toxicity. However, no effects were observed at the 5 µL/egg, suggesting that compensatory mechanisms were effective to maintain homeostasis in the developing embryo. To pursue a better understanding of these mechanisms, transcriptomic analyses of the jejunum were performed comparing the control injected with saline and the group injected with 5 µL of OEO. The transcriptomic analyses identified that 167 genes were upregulated and 90 were downregulated in the 5 µL OEO compared to the control group injected with saline (P < 0.01). Functional analyses of the differentially expressed genes (DEG) showed that metabolic pathways related to the epoxygenase cytochrome P450 pathway associated with xenobiotic catabolic processes were significantly upregulated (P < 0.05). In addition, long-chain fatty acid metabolism associated with ATP binding transporters was also upregulated in the OEO treated group (P < 0.05). The results indicated that low doses of OEO in ovo have the potential to increase lipid metabolism in late stages (E17.5) of embryonic development. In conclusion, in ovo delivery of 5 µL OEO did not show any negative impact on hatchability and chick quality. OEO elevated expression of key enzymes and receptors involved in detoxification pathways and lipid metabolism in the jejunum of hatchling broiler chicks.

The Effects of Tea Polyphenol on Chicken Protein Digestion and the Mechanism under Thermal Processing

Meat product is the main food and major source of daily protein intake. Polyphenols are always introduced into many meat products during processing. Some complex interactions may occur between polyphenol and meat protein during the processing, especially thermal processing, which may affect the digestion of protein. In this experiment, chicken protein and tea polyphenol were interacted in simulated systems to explore the effects of the interaction between meat protein and polyphenols on the digestion of meat protein. The mechanism of tea polyphenol inhibiting chicken protein digestion was studied by analyzing the changes of chicken protein in intrinsic fluorescence, surface plasmon resonance (SPR), reactive sulfhydryl group, and solubility in different solvents. The results showed that the chicken protein digestion had a negative correlation with tea polyphenol concentration and interaction temperature, and the meat protein has a higher affinity to EGCG than protease. The mechanism of tea polyphenol inhibiting chicken protein digestion was related to the changing spatial structure of chicken protein and the decreasing activity of proteases. In the simulation system, at low-concentration tea polyphenol, the inhibition of the tea polyphenol on the digestibility of chicken protein might be mainly caused by the changes in chicken protein structure, while at high concentration, the changes in protein structure and the inhibition of proteases activity played a role together. This experiment revealed the effect and the mechanism of polyphenols on the digestion performance of meat protein and provide more references for the further application of polyphenols in meat processing.

Inclusion of Quillaja Saponin Clarity Q Manages Growth Performance, Immune Response, and Nutrient Transport of Broilers during Subclinical Necrotic Enteritis

Necrotic enteritis (NE) is an intestinal disease that results in poor performance, inefficient nutrient absorption, and has a devastating economic impact on poultry production. This study evaluated the effects of a saponin-based product (Clarity Q, CQ) during an NE challenge. A total of 1200 male chicks were randomly assigned to four dietary treatments (10 pens/treatment; 30 birds/pen): treatment 1 (NC), a non-medicated corn-soybean basal diet; treatment 2 (PC), NC + 50 g/metric ton (MT) of bacitracin methylene disalicylate (BMD); and treatments 3 (CQ15) and 4 (CQ30), NC + 15 and 30 g/MT, respectively. On the day (d) of placement, birds were challenged by a coccidia vaccine to induce NE. On d 8, 14, 28, and 42, performance parameters were measured. On d 8, three birds/pen were necropsied for NE lesions. On d 8 and d 14, jejunum samples from one bird/pen were collected for mRNA abundance of tight junction proteins and nutrient transporter genes. Data were analyzed in JMP (JMP Pro, 16), and significance (p ≤ 0.05) between treatments was identified by Fisher's least significant difference (LSD) test. Compared to PC and NC, CQ15 had higher average daily gain (ADG), while CQ30 had lower average daily feed intake (ADFI) and feed conversion ratio (FCR). NE lesions in the duodenum were lower in CQ15 compared to all other treatments. On d 8, mRNA abundance of CLDN1, CLDN5, AMPK, PepT2, GLUT2, and EAAT3 were significantly greater in CQ30 (p < 0.05) compared to both PC and NC. On d 14, mRNA abundance of ZO2 and PepT2 was significantly lower in PC when compared to all treatments, while that of ANXA1, JAM3, and GLUT5 was comparable to CQ15. In summary, adding Clarity Q to broiler diets has the potential to alleviate adverse effects caused by this enteric disease by improving performance, reducing intestinal lesions, and positively modulating the mRNA abundance of various tight junction proteins and key nutrient transporters during peak NE infection.

Effect of dietary essential oil of oregano on performance parameters, gastrointestinal traits, blood lipid profile, and antioxidant capacity of laying hens during the pullet phase

Many benefits have been found in supplementing essential oils such as oregano oil (EOO) to poultry, including increased body weight gain, antioxidant activity, and better gastrointestinal morphology. However, few studies tested the influence of EOO supplementation on laying hens and reported conflicting results regarding its efficacy in improving their health and performance. Therefore, we aimed to explore the effects of dietary EOO on performance, gastrointestinal (GIT) traits, blood lipid, and antioxidant capacity in laying hens during the rearing phase. A total of 300-day-old Hy-line-Brown chicks were used, and treatment diets consisted of corn-soybean based either without (CON) or with EOO (Ecodiar®, 0.275 g/kg diet). Birds were randomized across treatments with five pens/treatment and 30-birds/pen. Pen weights and feed rejected were recorded every two weeks (1-17 weeks of age), to calculate daily feed intake (ADFI), body weight (BW), and daily weight gain (ADWG). At 11 and 14 weeks of age, blood samples were collected from 3 birds/pen and analyzed for blood lipids and antioxidant levels, and 5-birds/treatment were euthanized, and GIT traits were tested. Differences in measured parameters across weeks and between treatments were assessed using GLMM with Tukey’s Post hoc test applied to significant results in R 3.3.1 (α set at 0.05). Body weights at weeks 3, 11, 13, and 17 were significantly higher in the EOO group compared to the CON group (all P ≤ 0.05), ADWG was significantly higher in EOO birds compared to CON birds at 9 and 13 weeks old (all P ≤ 0.05), while no significant differences in ADFI were observed between treatments across weeks of the trials. At both 11 and 17 weeks old, triglyceride levels were significantly lower, while high-density-lipoprotein levels were higher in EOO (all P ≤ 0.05). Malondialdehyde levels were lower in the EOO group versus CON (p=0.01), while EOO birds had higher glutathione levels (p=0.01) than CON. Finally, at 12 weeks old, the weight of the entire GIT and empty gizzard were higher in the EOO group versus CON (all P ≤ 0.05), while liver and spleen weights were not significantly different between groups. In conclusion, dietary oregano supplementation exerted promoting effects on the performance of Hy-Line Brown pullets.

META-ANALYSIS OF PHYTOGENIC ADDITIVES FOR BROILERS

Phytogenic additives have been studied intensively in broiler chickens’ production to substitute growth-promoting antibiotics. However, the comprehensive literature on this topic makes it difficult to understand overall results because there are a noticeable number of studies with conflicting conclusions. While several research studies have shown that phytogenic additives may increment broiler chicken’s performance, others make the opposite evident. This study aimed to organize and understand information through meta-analysis considering a great number of publications and the factors that may interfere in the results of phytogenic additives, evaluating whether phytogenic additives can be used as a performance-enhancing additive for broilers, comparing with the effectiveness of growth-promoting antibiotics. The main factor that interferes in the evaluation of phytogenic additives is the microbiological challenge. Phytogenic additives improved average daily gain (ADG) (P < 0.001) and feed conversion (P < 0.001) regardless of microbiological challenge; however, they were worse compared to antibiotics under higher challenge (P < 0.020). A meta-regression of ADG in function of average daily feed intake confirmed that phytogenic additives increased the feed efficiency of broilers, but with less effectiveness than antibiotics. The blends of phytogenic additives increased the ADG in relation to the isolated use of only one phytogenic additive.

Antioxidant and antimicrobial activities of phytonutrients as antibiotic substitutes in poultry feed

Globally, there is increasing demand for safe poultry food products free from antibiotic residues. There is thus a need to develop alternatives to antibiotics with safe nutritional feed derivatives that maximize performance, promote the intestinal immune status, enrich beneficial microbiota, promote health, and reduce the adverse effects of pathogenic infectious microorganisms. With the move away from including antibiotics in poultry diets, botanicals are among the most important alternatives to antibiotics. Some botanicals such as fennel, garlic, oregano, mint, and rosemary have been reported to increase the poultry's growth rate and/or feed to gain ratio. Botanicals' role is assumed to be mediated by improved immune responses and/or shifts in the microbial population in the intestine, with the elimination of pathogenic species. In addition, modulation of the gut microbiota resulted in various physiological and immunological responses and promoted beneficial bacterial strains that led to a healthy gut. There is thus a need to understand the relationship between poultry diets supplemented with botanicals and good health of the entire gastrointestinal tract if we intend to use these natural products to promote general health status and production. This current review provides an overview of current knowledge about certain botanicals that improve poultry productivity by modulating intestinal health and reducing the negative impacts of numerous pathogenic bacteria. This review also describes the efficacy, negative effects, and modes of action of some common herbal plants applied in poultry as alternatives to reduce the use of antibiotics.

Phytogenic Feed Additives in Poultry: Achievements, Prospective and Challenges

Simple Summary

Plant secondary metabolites and essential oils also known as phytogenics are biologically active compounds that have recently attracted increased interest as feed additives in poultry production, due to their ability to promote feed efficiency by enhancing the production of digestive secretions and nutrient absorption, reduce pathogenic load in the gut, exert antioxidant properties and decrease the microbial burden on the animal’s immune status. However, the mechanisms are far from being fully elucidated. Better understanding the interaction of phytogenics with gastrointestinal function and health as well as other feed ingredients/additives is crucial to design potentially cost-effective blends.

Abstract

Phytogenic feed additives have been largely tested in poultry production with the aim to identify their effects on the gastrointestinal function and health, and their implications on the birds’ systemic health and welfare, the production efficiency of flocks, food safety, and environmental impact. These feed additives originating from plants, and consisting of herbs, spices, fruit, and other plant parts, include many different bioactive ingredients. Reviewing published documents about the supplementation of phytogenic feed additives reveals contradictory results regarding their effectiveness in poultry production. This indicates that more effort is still needed to determine the appropriate inclusion levels and fully elucidate their mode of actions. In this frame, this review aimed to sum up the current trends in the use of phytogenic feed additives in poultry with a special focus on their interaction with gut ecosystem, gut function, in vivo oxidative status and immune system as well as other feed additives, especially organic acids.

Essential Oil Delivery Route: Effect on Broiler Chicken's Growth Performance, Blood Biochemistry, Intestinal Morphology, Immune, and Antioxidant Status

Simple Summary

Much research is devoted to the search for potent alternatives to antibiotic growth promoters in the poultry industry. It is hypothesized that the efficacy of potential alternatives could be influenced by their type and the delivery strategy utilized. Consequently, this study evaluated the efficacy of a commercial essential oil blend across different delivery routes as a potent alternative to in-feed antibiotics in broiler chickens using selected biochemical, immune, and performance parameters. The results provide evidence that the successive delivery of essential oils via in ovo and in-water routes in broiler chickens offers the potential to improve broiler chicken biochemical and antioxidant status. However, the in ovo delivery of essential oil at 0.2 mL dosage (saline + essential oil, dilution ratio—2:1) suffers the limitations of reduced hatchability.

Abstract

This study evaluated the effect of an essential oil blend and its delivery routes on broiler chicken growth performance, blood biochemistry, intestinal morphology, and immune and antioxidant status. Eggs were incubated and allotted to 3 groups: non-injected group, in ovo saline group, and in ovo essential oil group. On day 18 of incubation, essential oil in saline or saline alone was injected into the amnion. At hatch, chicks were assigned to post-hatch treatment combinations (1) in ovo essential oil + in-water essential oil (in ovo + in-water EO); (2) in ovo essential oil (in ovo EO); (3) in ovo saline; (4) in-water essential oil; (5) in-feed antibiotics (Bacitracin methylene disalicylate) and (6) a negative control (NC; corn-wheat-soybean diet) in 8 replicate cages (6 birds/cage) and raised for 28 day. The in ovo EO group reduced (p < 0.05) chick length and hatchability, all groups recorded no difference in growth performance at 0–28 day. The in ovo + in-water EO treatment reduced (p < 0.05) blood creatine kinase and aspartate aminotransferase levels whilst increasing (p < 0.05) total antioxidant capacity in birds. The in ovo + in-water delivery of EO might represent a potential antibiotic reduction strategy for the poultry industry but more research is needed to address the concern of reduced hatchability.

Citral alleviates peptidoglycan-induced inflammation and disruption of barrier functions in porcine intestinal epithelial cells

Peptidoglycan (PGN) is a major polymer in bacterial cell walls and may constrain gut functionality and lower intestinal efficiencies in livestock. Citral has been reported to exhibit antibacterial and anti-inflammatory biological activities, improving the gastrointestinal function of swine. However, the protective effect of citral against PGN-elicited cellular responses and possible underlying mechanisms are unknown. In this study, the porcine jejunal epithelial cell line (IPEC-J2) was challenged with PGN from Staphylococcus aureus (S. aureus) or Bacillus subtilis (B. subtilis) to explore PGN-induced inflammatory responses. Our data showed that the inflammatory response stimulated by PGN from harmful bacteria (S. aureus) was more potent than that from commensal bacteria (B. subtilis) in IPEC-J2 cells. Based on the inflammatory model by PGN from S. aureus, it was demonstrated that PGN could significantly induce inflammatory cytokine production and influence nutrient absorption and barrier function in a dose-dependent manner. However, the PGN-mediated immune responses were remarkably suppressed by citral. In addition, citral significantly attenuated the effect of PGN on the intestine nutrient absorption and barrier function. The expression of TLR2 was strongly induced by PGN stimulation, which was suppressed by citral. All data nominated that citral downregulated PGN-induced inflammation via TLR2-mediated activation of the NF-κB signaling pathway in IPEC-J2 cells. Furthermore, the results also indicate that the PGN degradation through the inclusion of enzymes (e.g., muramidase) as well as the inclusion of citral for attenuating inflammation may improve pig gut health and functionality.

Influence of Trans-anethole on the nutrient digestibility and intestinal barrier function in broilers

This experiment was undertaken to investigate the effects of dietary trans-anethole (TA) at 5 levels (0, 200, 400, 600, and 800 mg/kg of diet) on the growth performance, apparent nutrient digestibility and intestinal barrier function in broilers. Three hundred twenty 1-day-old Arbor Acres broilers were randomly divided into the 5 dietary treatments with 8 replicates each for 42 d. Dietary TA supplementation increased (P < 0.05) average daily feed intake (ADFI), but had no effects (P > 0.05) on average daily gain (ADG), feed/gain (F/G), and body weight (BW) of broilers throughout the entire experimental period. The apparent metabolizable energy (AME) and nitrogen-corrected apparent metabolizable energy (AMEn), the apparent total tract digestibility of dry matter (DM), crude protein (CP), organic matter (OM), and gross energy (GE) showed a quadratic increase (P < 0.05) with the increasing TA concentration in the diet. The apparent ileal digestibility of Lys, Met, Leu, Thr, Ala, Tyr, and Pro were higher (P < 0.05) in birds fed TA diets compared with control group. Dietary supplementation of 400 mg/kg of TA increased (P < 0.05) mRNA levels of jejunal and ileal Na+/glucose co-transporter (SGLT1) on d 21 and d 42, oligopeptide transporter 1 (PepT1) on d 42, and ileal mRNA expressions of occludin (OCLN), claudin-1 (CLDN-1), and mucin 2 (MUC2), villus height (VH), crypt depth (CD), and VH:CD on d 21, as well as jejunal zonula-occludens-1 (ZO-1) and ileal mucin 2 on d 42. Linear or quadratic responses of the jejunal CD and villus VH:CD ratio occurred (P < 0.01) with increasing dietary TA concentration on d 42. The inclusion of 400 mg/kg TA decreased (P < 0.05) cecal Escherichia coli population on d 21 and d 42, but increased (P < 0.05) Bifidobacterium population on d 21 and ileal Bifidobacterium on d 42. In conclusion, 400 mg/kg of TA is the optimum concentration for increasing nutrient utilization and intestinal barrier function of broilers.

Effects of trans-anethole supplementation on serum lipid metabolism parameters, carcass characteristics, meat quality, fatty acid, and amino acid profiles of breast muscle in broiler chickens

This study investigated the effects of trans-anethole (TA) supplementation on the carcass characteristics, meat quality, fatty acid, and amino acid profiles of breast muscle in broilers. A total of 40 one-day-old male broiler chicks (Arbor Acres) were randomly allocated to 5 treatments, respectively, fed a corn-soybean basal diet supplemented with 0 (control), 200, 400, 600, and 800 mg TA/kg diet for 42 d. 600 mg/kg of TA supplementation decreased (P < 0.05) serum triglycerides (TG) on d 21 and d 42, and high density lipoprotein cholesterol (HDL-C) concentration on d 21, but increased (P < 0.01) serum HDL-C concentration on d 42. Dietary supplementation of TA increased (P < 0.01) the half chamber rate (HCR) and eviscerated rate (ER) of broilers. The drip loss (storing 24 and 48 h) and cooking loss of breast muscle in 600 mg/kg TA groups were lower (P < 0.05) than those in control group. The concentration of palmitoleic acid, daturic acid, oleic acid, linoleic acid, α-Linolenic acid, eicostrienoic acid, and pentosapentanoic acid (EPA), MUFA, and PUFA in the breast muscle were higher (P < 0.05) in the 600 mg/kg of TA group compared with other groups. Dietary inclusion of 600 mg/kg of TA also increased (P < 0.05) the concentration of Met, Thr, Asp, Ser, and Glu in breast muscle, tended to increase (P = 0.069) the Lys concentration. In conclusion, results indicated that TA inclusion improved the lipid metabolism, meat quality, fatty acid composition, and amino acid profile of breast muscle in broilers.

Effects of dietary rosemary extract supplementation on growth performance, nutrient digestibility, antioxidant capacity, intestinal morphology, and microbiota of weaning pigs

Rosemary (Rosmarinus officinalis L.) extract (RE) has multiple pharmacological and biological activities, including the use as a food additive and medicine. This study was conducted to investigate the effects of dietary RE supplementation on the growth performance, nutrient digestibility, antioxidant capacity, intestinal morphology, and microbiota of weaning piglets. A total of 192 crossbred weaned piglets [Duroc × (Large White × Landrace)] (initial body weight = 6.65 ± 0.33 kg, weaned days = 23 ± 1 d) were group housed (six pigs per pen; n = 8 pens/treatment). Pigs were fed a corn-soybean meal-based control diet or the basal diet supplemented with 100, 200, or 400 mg/kg RE. Pigs were allowed ad libitum access to fed for 21 d. The growth performance and apparent total tract digestibility of nutrients, and intestinal morphology and antioxidant status were evaluated. The components of the microbial microflora were also determined in the cecal samples. Compared with the control, dietary supplementation with RE increased the final body weight, average daily gain, and average daily feed intake (linear, P = 0.038, 0.016, and 0.009, respectively), and decreased the diarrhea ratio in piglets (linear, P < 0.05). The digestibility of crude protein (linear, P = 0.034) and gross energy (linear, P = 0.046) increased with treatment with RE. Piglets fed RE showed longer villus height (linear, P = 0.037 and 0.028, respectively) and villus height/crypt depth (linear, P = 0.004 and 0.012; quadratic, P = 0.023 and 0.036, respectively) in the jejunum and ileum, in addition to a lesser crypt depth in the jejunum (linear, P = 0.019) and ileum (quadratic, P = 0.042). The addition of RE increased the activity of superoxide dismutase (linear, P = 0.035 and 0.008, respectively) and glutathione peroxidase activity (linear, P = 0.027 and 0.039, respectively) and decreased the content of malondialdehyde (linear, P = 0.041 and 0.013; quadratic, P = 0.023 and 0.005, respectively) in the serum and liver. Dietary RE supplementation, compared with the control, increased the number of Bifidobacterium (linear, P = 0.034) and Bacteroidetes (linear, P = 0.029), while decreased Escherichia coli (linear, P = 0.008; quadratic, P = 0.014) in the cecal contents. Thus, dietary RE supplementation can improve growth performance, nutrient digestibility, antioxidant capacity, intestinal morphology, and the microbiota in weaned piglets, and 200 mg/kg may be considered the optimum dosage.

Can Yucca schidigera Be Used to Enhance the Growth Performance, Nutrient Digestibility, Gut Histomorphology, Cecal Microflora, Carcass Characteristic, and Meat Quality of Commercial Broilers Raised under Tropical Conditions?

This study aims to study the effect of Yucca shidigera as a phytobiotic supplementation in enhancing the production performance of commercial broilers reared under tropical environments. A total of 300 male day-old Ross 308 broiler chicks were randomly allocated into six treatment groups. Treatment 1 broilers were fed with commercial diets without antibiotics. Treatment 2 broilers were fed with commercial diets added with 100 mg/kg oxytetracycline antibiotic. Treatment 3, 4, 5, and 6 were fed with the same commercial diets added with 25, 50, 75, and 100 mg/kg Y. shidigera, respectively, without antibiotic. Throughout the six weeks study period, body weight and feed intake were recorded weekly for each replicate to calculate the body weight gain and feed conversion ratio. In addition, the nutrient digestibility, gut histomorphology, cecal microflora population, carcass characteristics, and meat quality were determined. The results showed significant differences (p < 0.05) in the growth performance, apparent ileal nutrient digestibility, gut histomorphology, carcass traits, and meat quality. Overall, T6 broilers supplemented with 100 mg/kg Y. shidigera demonstrated the best production performances as compared to the other treatment broilers. In summary, information from this study will be valuable for the usability of Y. schidigera, which could be developed as a feed additive to replace antibiotics in the poultry sector in the tropics.

Effects of star anise (Illicium verum Hook.f.) essential oil administration under three different dietary energy levels on growth performance, nutrient, and energy utilization in broilers

This experiment was conducted to investigate the effect of star anise essential oil (SAO) supplementation in diets with different energy levels on growth performance, nutrient metabolic efficiency of broilers. One hundred and ninety-two Arbor Acres male broiler chicks at 28 days of age were divided into a 3 × 4 factorial arrangement design with three dietary energy levels (13.41, 12.82, 12.23 MJ/kg) and 4 levels of SAO supplementation (0, 200, 400, and 600 mg/kg of diet). Dietary supplementation with SAO increased (p < .05) apparent metabolic efficiency of CP, EE, GE, and all of the amino acids except Trp. Significant interactions were noted between energy level and SAO administration for metabolic efficiency of CP, all of the amino acids except Cys. Inclusion of SAO enhanced apparent nutrient metabolic efficiency of broilers in a dose-dependent manner, birds supplemented with 400 mg/kg of SAO in high-energy diets appeared to contain highest nutrient metabolic efficiency, moreover, the metabolic efficiency of nutrients in low-energy diets along with 200 or 400 mg/kg of SAO was similar with that in high-energy diets without SAO, which indicated that the SAO might ameliorate the negative effects of reduced dietary metabolic energy on nutrient utilization in broilers.

Dietary oregano essential oil supplementation improves intestinal functions and alters gut microbiota in late-phase laying hens

BACKGROUND

Dietary essential oil (EO) supplementation can exert favorable effects on gut health in broilers. However, it is unknown whether EO could improve intestinal functions, consequently beneficial for egg performance and quality in late-phase laying hens. This study was aimed to investigate the potential effects of EO on production performance, egg quality, intestinal health and ileal microbiota of hens in the late phase of production. A total of 288 60-week-old Hy-line Brown laying hens were randomly divided into 4 groups and fed a basal diet (control) or basal diets supplemented with oregano EO at 100, 200 and 400 mg/kg (EO100, EO200 and EO400).

RESULTS

Dietary EO supplementation resulted in a quadratic decrease (P < 0.05) in feed conversion ratio with lower (P < 0.05) feed conversion ratio in EO200 group than the control during weeks 9-12 and 1-12 of the trial. Compared to the control, EO addition resulted in higher (P < 0.05) eggshell thickness at the end of week. 4, 8 and 12 and higher (P < 0.05) chymotrypsin activity. There was a quadratic elevation (P < 0.05) in ileal chymotrypsin and lipase activity, along with a linear increase in villus height to crypt depth ratio. Quadratic declines (P < 0.05) in mRNA expression of IL-1β, TNF-α, IFN-γ and TLR-4, concurrent with a linear and quadratic increase (P < 0.05) in ZO-1 expression were identified in the ileum with EO addition. These favorable effects were maximized at medium dosage (200 mg/kg) of EO addition and intestinal microbial composition in the control and EO200 groups were assessed. Dietary EO addition increased (P < 0.05) the abundances of Burkholderiales, Actinobacteria, Bifidobacteriales, Enterococcaceae and Bacillaceae, whereas decreased Shigella abundance in the ileum.

CONCLUSIONS

Dietary EO addition could enhance digestive enzyme activity, improve gut morphology, epithelial barrier functions and modulate mucosal immune status by altering microbial composition, thus favoring feed efficiency and eggshell quality of late-phase laying hens.

Effects of oregano essential oil as an antibiotic growth promoter alternative on growth performance, antioxidant status, and intestinal health of broilers

This experiment was conducted to assess the comparative effects of dietary antibiotics and oregano essential oil (OEO) addition on growth performance, antioxidant status and intestinal health of broilers. A total of 384 one-day-old broilers were randomly allocated to 4 treatments with 6 replicates of 16 broilers each. The 4 treatments were: an antibiotic-free control diet (control), control + 20 mg/kg colistin sulfate and 20 mg/kg virginiamycin (antibiotics), control + 200 mg/kg natural oregano essential oil (NOEO), and control + 200 mg/kg synthetic oregano essential oil (SOEO). The experiment lasted for 42 d. Results showed that birds fed with OEO had greater (P < 0.05) average daily gain (ADG) and lower (P < 0.05) feed conversion ratio (FCR) than those fed with control diet during d 1 to 21. Besides, birds fed with NOEO had the greatest (P < 0.05) ADG in the four groups during d 22 to 42. The serum oxidative stress parameters showed that OEO improved (P < 0.05) the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione reductase (GR) of birds on day 21 and the activity of total antioxidant capacity (T-AOC) of birds on d 42. Relative to control, NOEO increased (P < 0.05) the activity of T-AOC in jejunum and decreased (P < 0.05) the level of malondialdehyde (MDA) in serum and jejunum. Moreover, OEO supplementation increased (P < 0.05) the concentrations of sIgA in duodenum and jejunum, Lactobacillus and total anaerobes in cecum, as well as activities of trypsin, chymotrypsin, lipase and amylase in duodenum, but restrained (P < 0.05) the amount of Escherichia coli. The NOEO supplementation increased (P < 0.05) total anaerobes of broilers on d 42 and the villus height to crypt depth ratio (VH/CD) of ileum. These results suggest that OEO improved antioxidant status and intestinal health of broilers which contributed to the growth performance improvement of broilers. Dietary OEO supplementation can be a promising alternative to antibiotic growth promoters for improving poultry production.

Effect of a Phytogenic Water Additive on Growth Performance, Blood Metabolites and Gene Expression of Amino Acid Transporters in Nursery Pigs Fed with Low-Protein/High-Carbohydrate Diets

Simple Summary

Low-protein (LP) diets can be potentially used to reduce the excretion of nitrogenous compounds and feed cost in commercial swine production; however, new strategies are required to be developed to improve the growth performance of pigs receiving these diets. Little is known about the effect of phytogenic additives on the performance of pigs fed with LP diets and the underlying factors involved. The objective of this study was to assess the effect of a phytogenic water additive (PWA) on growth performance, nutrient digestibility, blood metabolites, plasma amino acid (AA) concentration, and gut and skeletal muscle AA transporters in nursery pigs fed with LP diets. Supplemental PWA increased the concentration of circulating essential AA, reduced the transcript of some of the AA transporters in the small intestine and skeletal muscle, improved growth performance when the dietary protein was adequate, and increased muscle lean%, but reduced muscle fat% when the dietary protein was deficient. The used PWA in this study had differential effects on blood calcium and its digestibility depending on the level of dietary protein. This study suggests that PWA can be used for improving the meat composition in protein-restricted pigs, but PWA improves growth performance only when dietary protein is adequate.

Abstract

The objective of this study was to investigate the effect of a phytogenic water additive (PWA) on growth performance and underlying factors involved in pigs fed with low-protein (LP)/high-carbohydrate diets. Forty-eight weaned barrows were allotted to six treatments for 4 weeks: CON-NS, control (CON) diet-no PWA; CON-LS, CON diet-low dose PWA (4 mL/L); CON-HS, CON diet-high dose PWA (8 mL/L); LP-NS, LP diet-no PWA; LP-LS, LP diet-low dose PWA; LP-HS, LP diet-high dose PWA. Relative to CON-NS, pigs fed with CON-HS had increased average daily gain, body weight and serum calcium (Ca) and phosphorous (P) and had decreased mRNA abundance of solute carrier family 7 member 11 and solute carrier family 6 member 19 in jejunum. Compared to LP-NS, pigs fed with LP-HS had increased muscle lean%, decreased muscle fat%, decreased serum Ca and increased serum P. Compared to their NS counterparts, CON-LS, CON-HS, and LP-LS increased the concentration of plasma essential AA and those fed with CON-HS and LP-HS tended to reduce the abundance of the solute carrier family 7 member 1 transcript in skeletal muscle. Thus, PWA improved the performance of weaned pigs fed with protein-adequate diets likely through increased blood essential AA and affected the muscle composition when dietary protein was deficient.

Protective effects of the phytogenic feed additive "comfort" on growth performance via modulation of hypothalamic feeding- and drinking-related neuropeptides in cyclic heat-stressed broilers

Identification of alternatives to antibiotics in livestock and poultry is necessary. Fueled by consumer preferences, phytogenic feed additives are increasingly used in the food system; however, their mode of action is not well defined. Here, we used broiler chickens, in which appetite and feeding behavior regulation are controlled by complex mechanisms, to determine the effect of the phytogenic feed additive "comfort" (PFA-C) as well as its underlying molecular mechanisms on growth performance in heat-stressed broiler chickens. Heat stress significantly increased birds' core body temperature, water intake, and the hypothalamic expression of heat shock protein (HSP) 70, whereas it decreased feed intake, BW, and woody breast incidence. Phytogenic feed additive "comfort" supplementation downregulated the hypothalamic expression of HSP70, reduced core body temperature, increased feed and water intake, and improved BW in HS broilers. At molecular levels, the effect of PFA-C on growth performance seemed to be mediated by modulation of hypothalamic expression of melanocortin receptor 2, arginine vasopressin, aquaporin 2, and sodium and potassium-transporting ATPase subunit beta 1 polypeptides. In summary, PFA-C supplementation ameliorates heat stress productivity losses via a potential cytoprotective effect, reduction of hypothalamic intracellular stress, and modulation of hypothalamic feeding- and drinking-related polypeptide expression.

Fermented traditional Chinese medicine alters the intestinal microbiota composition of broiler chickens

For a long time, phytogenic resources have been widely used as substitutes for antibiotics in livestock production. However, few studies have examined the relationship between the intestinal microbiota and fermented herbal medicines. Here, 252 Arbor Acres broiler plus broiler chickens were randomly assigned to a control group, which was fed a basal diet; an unfermented healthy chicken powder group (JJS) fed a basal diet containing 20 g/kg JJS; or one of 5 fermented JJS groups, which were fed a basal diet containing 20 g/kg JJS, fermented with by 5 different bacterial strains for 42 days. The growth performances of the different groups were measured and the changes in the intestinal microbiota were analyzed. The body weight gain in the Bacillus subtilis group (Bs) was the highest among the 6 groups, while the feed conversion ratio (FCR) was best with Z. rouxii fermentation. The result indicated that products of JJS fermentation products of JJS by B. subtilis and Z. rouxii had important effects on chicken growth performance. The foregut and hindgut microbial communities of Bs, Zr, the control group and the JJS group, were collected for 16S rDNA sequencing. The results showed that JJS and its fermentation products mainly acted on the foregut and had little effect on the hindgut, and Z. rouxii fermentation products can increased the diversity in the foregut microbial community. In addition, the relative abundance of Bifidobacterium in the foregut of the Z. rouxii group was significantly increased, which may be an important factor in promoting growth.

Acute, reproductive, and developmental toxicity of essential oils assessed with alternative in vitro and in vivo systems

Essential oils (EOs) have attracted increased interest for different applications such as food preservatives, feed additives and ingredients in cosmetics. Due to their reported variable composition of components, they might be acutely toxic to humans and animals in small amounts. Despite the necessity, rigorous toxicity testing in terms of safety evaluation has not been reported so far, especially using alternatives to animal models. Here, we provide a strategy by use of alternative in vitro (cell cultures) and in vivo (Caenorhabditis elegans, hen’s egg test) approaches for detailed investigation of the impact of commonly used rosemary, citrus and eucalyptus essential oil on acute, developmental and reproductive toxicity as well as on mucous membrane irritation. In general, all EOs under study exhibited a comparable impact on measured parameters, with a slightly increased toxic potential of rosemary oil. In vitro cell culture results indicated a concentration-dependent decrease of cell viability for all EOs, with mean IC₅₀ values ranging from 0.08 to 0.17% [v/v]. Similar results were obtained for the C. elegans model when using a sensitized bus-5 mutant strain, with a mean LC₅₀ value of 0.42% [v/v]. In wild-type nematodes, approximately tenfold higher LC₅₀ values were detected. C. elegans development and reproduction was already significantly inhibited at concentrations of 0.5% (wild-type) and 0.1% (bus-5) [v/v] of EO, respectively. Gene expression analysis revealed a significant upregulation of xenobiotic and oxidative stress genes such as cyp-14a3, gst-4, gpx-6 and sod-3. Furthermore, all three EOs under study showed an increased short-time mucous membrane irritation potential, already at 0.5% [v/v] of EO. Finally, GC–MS analysis was performed to quantitate the relative concentration of the most prominent EO compounds. In conclusion, our results demonstrate that EOs can exhibit severe toxic properties, already at low concentrations. Therefore, a detailed toxicological assessment is highly recommended for each EO and single intended application.

Effect of essential oils or saponins alone or in combination on productive performance, intestinal morphology and digestive enzymes' activity of broiler chickens

This study was carried out to evaluate the effect of essential oils or saponins alone or in combination on productive performance, intestinal morphology, and digestive enzymes' activity in broilers. Four hundred one-day-old male broiler chickens were randomly assigned to four treatments, each with 5 replicates. The birds were fed experimental diets contained either no phytogenic feed additives (control) or were supplemented with 25.0 mg/kg of an essential oil blend from star anise, rosemary, thyme and oregano (essential oils); 46.0 mg/kg of a Quillaja saponin blend (saponins); or a combination of both phytogenic preparations (essential oils plus saponins). The experiment lasted for 42 days. Body weight, feed intake and weight gain were recorded weekly, and the feed conversion ratio was calculated, throughout the experiment. Intestinal morphology and digestive enzymes' activity were determined at the end of the experiment. It was found that the body weight was increased by all dietary supplements at the end of the experiment. There was no change in performance parameters among the treatments during the starter period. At the grower period and the overall experiment, the weight gain of birds was higher in all supplemented groups compared to the control, but the feed conversion was better in the essential oils with saponins treatment. Supplementation of essential oils or saponins alone or in combination increased the villus height and the villus/crypt ratio of the intestine. There was an increase in trypsin, chymotrypsin and elastase activities in the essential oils plus saponins group only. The obtained results indicate that the phytogenic feed additives, especially essential oils with saponins, can be considered as new promising agents in promoting the growth performance of broilers. The effect could be related to its improving impact in intestinal development and increasing the protease enzymes' activity, resulting in increased protein digestibility and absorption of dietary nutrients.

Host-Microbiota Interactions in Ileum and Caecum of Pigs Divergent in Feed Efficiency Contribute to Nutrient Utilization

The composition of the intestinal microbiota plays an important role in the digestion and utilization of nutrients and for gut health. Low-fiber diets stimulate digestion and absorption processes, predominantly in the upper region of the gastrointestinal tract, thereby increasing the conversion of feed into body weight. As a consequence, the chemical composition of digesta after duodenal and jejunal absorption processes and passage has a limited complexity affecting colonization and molecular profiles of enterocytes in the hind gut. To decipher ileal and caecal microbial ecosystems and host transcriptional profiles that are beneficial for effective use of the remaining nutrients, pigs differing in feeding efficiency were studied. Biological functions that were consistently enriched at both the gene and microbiota levels comprise immunity-related processes, which ensure the integrity of the gastrointestinal tract. In addition, the differential abundance of certain genera, including Rothia, Subdoligranulu, Leeia and Cellulosilyticum, reflects the establishment of a microbial profile that supports the digestion of endogenously indigestible dietary components in highly feed-efficient pigs. Overall, the results indicate the potential to promote these beneficial functions and further improve feed efficiency through manipulation of dietary and probiotic strategies.

(-)-α-Pinene reduces quorum sensing and Campylobacter jejuni colonization in broiler chickens

Campylobacter jejuni is one of the most prevalent causes of bacterial gastroenteritis worldwide, and it is largely associated with consumption of contaminated poultry. Current Campylobacter control measures at the poultry production level remain insufficient, and hence there is the need for alternative control strategies. We evaluated the potential of the monoterpene (-)-α-pinene for control of C. jejuni in poultry. The antibacterial and resistance-modulatory activities of (-)-α-pinene were also determined against 57 C. jejuni strains. In addition, the anti-quorum-sensing activity of (-)-α-pinene against C. jejuni NCTC 11168 was determined for three subinhibitory concentrations (125, 62.5, 31.25 mg/L) over three incubation times using an autoinducer-2 bioassay based on Vibrio harveyi BB170 bioluminescence measurements. The effects of a subinhibitory concentration of (-)-α-pinene (250 mg/L) on survival of C. jejuni, and in combination with enrofloxacin on fluoroquinolone resistance development in C. jejuni, were determined in a broiler chicken model, by addition of (-)-α-pinene to the broiler water supply. The reduction of C. jejuni numbers by (-)-α-pinene was further determined in broiler chickens that were colonized with either fluoroquinolone-susceptible or -resistant strains, by direct gavage treatment. We observed weak in vitro antimicrobial activity for (-)-α-pinene alone (MIC >500 mg/L), but strong potentiating effects on antibiotics erythromycin and ciprofloxacin against different Campylobacter strains (>512 fold change). After 24 h of treatment of C. jejuni with (-)-α-pinene, its quorum-sensing signaling was reduced by >80% compared to the untreated control. When given in the drinking water, (-)-α-pinene did not show any significant inhibitory effects on the level of C. jejuni in the colonized chickens, and did not reduce fluoroquinolone resistance development in combination with enrofloxacin. Conversely, when (-)-α-pinene was administered by direct gavage, it significantly reduced the number of fluoroquinolone susceptible C. jejuni in the colonized broiler chickens. These results demonstrate that (-)-α-pinene modulates quorum-sensing in Campylobacter, potentiates antibiotics against different Campylobacter strains, and reduces Campylobacter colonization in broiler chickens.

Mexican oregano essential oils given in drinking water on performance, carcass traits, and meat quality of broilers

The objective of this study was to evaluate the effects of 2 Mexican oregano essential oils (MOO), from Poliomintha longiflora Gray (PLG) and Lippia berlandieri Schauer (LBS), in drinking water (DWt) on the performance, slaughter variables, and meat quality of broilers over a 40 D period of growth. A total of 180 non-sexed Ross-308 broilers (1-day-old) were randomly assigned to 3 treatments with 6 replications each (10 birds per replicate): CON = DWt control (without MOO); PLG = DWt + 400 mg/L of PLG; and LBS = DWt + 400 mg/L of LBS. The CON, PLG, and LBS broilers body weights were similar (P > 0.05) at all times. Feed intake (FI) was different by treatment (P < 0.05) at 7 and 28 D, and water intake (WI) was different (P < 0.05) at day 28. The CON treatment was highest (P < 0.05) at 28 D for FI and WI, whereas LBS was lowest (P < 0.05). Weight gain (WG) for CON, PLG, and LBS broilers was similar (P > 0.05), although WG for CON was slightly higher. In CON broilers, slaughter weight was highest (P < 0.05), but thigh yield was lowest (P < 0.05). The CON and PLG treatments were lower (P < 0.05) in thigh and leg cooking losses. The PLG treatment presented the highest values (P < 0.05) for breast-meat redness, saturation index, shear force, odor, taste, and overall sensory acceptability. The LBS was higher (P < 0.05) for breast-meat shear force, cohesiveness and resilience, but lower (P < 0.05) for sensory attributes. Mexican oregano essential oils at 400 mg/L can serve as natural alternative additives in DWt to improve broiler production and meat quality.

Effects of Starch on the Digestibility of Gluten under Different Thermal Processing Conditions

Gluten and starch are the primary ingredients of wheat. The complex reaction between gluten and starch will occur during thermal food processing, which will affect digestibility. The effects of proteins on the digestibility of starch have been reported, but the effects of starch on the digestibility of proteins have not been well-researched. In this paper, the effects of starch on gluten digestion during the heating process were studied by the gluten-starch simulated system, and it was found that starch can enhance gluten digestion. When the complex of 1:1 gluten-starch is heated at 100 °C, the digestibility of gluten is higher and more low-molecular-weight peptides are produced. Results from the digestibility and digestion peptide mapping of the gluten-starch complex at different conditions showed that the addition of starch during processing enhanced the digestion performance of gluten. Meanwhile, the secondary structure, intrinsic fluorescence, and microscopic structure of the gluten-starch complex were investigated to understand the mechanism of the enhancement. The digestion performance is related to the secondary structure variation during the thermal processing caused by the hydration increase and disulfide bond reduction. The gluten-starch complex spatial structure is looser than gluten after heating, which could expose more protease cleavage sites. These results suggest that starch can protect gluten from aggregation in water and destroy the spatial structure of gluten with the assistance of heating, exposing more cleavage sites and enhancing gluten digestion.

Thymol Improves Barrier Function and Attenuates Inflammatory Responses in Porcine Intestinal Epithelial Cells during Lipopolysaccharide (LPS)-Induced Inflammation

It is well-known that essential oil thymol exhibits antibacterial activity. The protective effects of thymol on pig intestine during inflammation is yet to be investigated. In this study, an in vitro lipopolysaccharide (LPS)-induced inflammation model using IPEC-J2 cells was established. Cells were pretreated with thymol for 1 h and then exposed to LPS for various assays. Interleukin 8 (IL-8) secretion, the mRNA abundance of cytokines, reactive oxygen species (ROS), nutrient transporters, and tight junction proteins was measured. The results showed that LPS stimulation increased IL-8 secretion, ROS production, and tumor necrosis factor alpha (TNF-α) mRNA abundance ( P < 0.05), but the mRNA abundance of sodium-dependent glucose transporter 1 (SGLT1), excitatory amino acid transporter 1 (EAAC1), and H⁺/peptide cotransporter 1 (PepT1) were decreased ( P < 0.05). Thymol blocked ROS production ( P < 0.05) and tended to decrease the production of LPS-induced IL-8 secretion ( P = 0.0766). The mRNA abundance of IL-8 and TNF-α was reduced by thymol pretreatment ( P < 0.05), but thymol did not improve the gene expression of nutrient transporters ( P > 0.05). The transepithelial electrical resistance (TEER) was reduced and cell permeability increased by LPS treatment ( P < 0.05), but these effects were attenuated by thymol ( P < 0.05). Moreover, thymol increased zonula occludens-1 (ZO-1) and actin staining in the cells. However, the mRNA abundance of ZO-1 and occludin-3 was not affected by either LPS or thymol treatments. These results indicated that thymol enhances barrier function and reduce ROS production and pro-inflammatory cytokine gene expression in the epithelial cells during inflammation. The regulation of barrier function by thymol and LPS may be at post-transcriptional or post-translational levels.

Probiotics and plant-derived compounds as eco-friendly agents to inhibit microbial toxins in poultry feed: a comprehensive review

Some of pathogenic bacteria and fungi have the ability to produce fetal toxins which may be the direct causes of cytotoxicity or cellular dysfunction in the colonization site. Biological and non-biological environmental factors, challenge and microbes influence the effect of toxins on these pathogens. Modern research mentions that many natural materials can reduce the production of toxins in pathogenic microbes. However, researches that explain the mechanical theories of their effects are meager. This review aimed to discuss the ameliorative potential role of plant-derived compounds and probiotics to reduce the toxin production of food-borne microbes either in poultry bodies or poultry feedstuff. Moreover, studies that highlight their own toxicological mechanisms have been discussed. Adding natural additives to feed has a clear positive effect on the enzymatic and microbiological appearance of the small intestine without any adverse effect on the liver. Studies in this respect were proposed to clarify the effects of these natural additives for feed. In conclusion, it could be suggested that the incorporation of probiotics, herbal extracts, and herbs in the poultry diets has some beneficial effects on productive performance, without a positive impact on economic efficiency. In addition, the use of these natural additives in feed has a useful impact on the microbiological appearance of the small intestine and do not have any adverse impacts on intestinal absorption or liver activity as evidenced by histological examination.