Effects of dietary betaine supplementation on growth performance, meat quality, muscle fatty acid composition and antioxidant ability in slow-growing broiler chickens

Integrating metabolomics and transcriptomics to analyze the differences of breast muscle quality and flavor formation between Daweishan mini chicken and broiler

The quality and flavor of chicken are affected by muscle metabolites and related regulatory genes, and the molecular regulation mechanism of meat quality is different among different breeds of chicken. In this study, 40 one-day-old Daweishan mini chicken (DM) and Cobb broiler (CB) were selected from each group, with 4 replicates and 10 chickens in each replicate. The chickens were reared until 90 d of age under the same management conditions. Then, metabolomics and transcriptomics data of 90-day-old DM (n = 4) and CB (n = 4) were integrated to analyze metabolites affecting breast muscle quality and flavor, and to explore the important genes regulating meat quality and flavor related metabolites. The results showed that a total of 38 significantly different metabolites (SDMs) and 420 differentially expressed genes (DEGs) were detected in the breast muscle of the 2 breeds. Amino acid and lipid metabolism may be the cause of meat quality and flavor difference between DM and CB chickens, involving metabolites such as L-methionine, betaine, N6, N6, N6-Trimethyl-L-lysine, L-anserine, glutathione, glutathione disulfide, L-threonine, N-Acetyl-L-aspartic acid, succinate, choline, DOPC, SOPC, alpha-linolenic acid, L-palmitoylcarnitine, etc. Important regulatory genes with high correlation with flavor amino acids (GATM, GSTO1) and lipids (PPARG, LPL, PLIN1, SCD, ANGPTL4, FABP7, GK, B4GALT6, UGT8, PLPP4) were identified by correlation analysis, and the gene-metabolite interaction network of breast muscle mass and flavor formation in DM chicken was constructed. This study showed that there were significant differences in breast metabolites between DM and CB chickens, mainly in amino acid and lipid metabolites. These 2 kinds of substances may be the main reasons for the difference in breast muscle quality and flavor between the 2 breeds. In general, this study could provide a theoretical basis for further research on the molecular regulatory mechanism of the formation of breast muscle quality and flavor differences between DM and CB chickens, and provide a reference for the development, utilization and genetic breeding of high-quality meat chicken breeds.

Effect of in-ovo inoculation of betaine on hatchability, serum antioxidant levels, muscle gene expression and intestinal development of broiler chicks

This study investigated the effects of in-ovo inoculation of betaine on hatchability, hatching weight, and intestinal development, as well as serum and expression levels of some antioxidants in the posthatched chicks. A total of 350 fertile eggs of Hubbard efficiency plus breeder's flock were incubated at normal incubation temperature (37.5°C) and randomly assembled into 3 groups with 4 replicates, and 25 eggs per each. The experimental groups were allocated as noninjected control group (CN), diluent-injected group (CP, 0.1 mL saline), and betaine-injected group (B, 2.5 mg in 0.1 mL saline). The injections were performed in the air cells of the eggs on the 12th day of the embryonic phase. Hatchability percentage, hatching weight, serum-reduced glutathione (GSH), and superoxide dismutase (SOD) were estimated in 7-day-old chicks. Moreover, expression levels of the nuclear factor erythroid 2-related factor 2 (Nrf2) and SOD were determined in the breast skeletal muscles of chicks. Jejunum histo-morphometric analysis was assessed with computerised morphometric measurements. The results revealed that the hatchability percentage was not influenced by in-ovo injection of betaine or vehicle while betaine significantly increased the hatchling's weight of chicks. Moreover, there were a significant increase in SOD and Nrf2 mRNA expression levels. In-ovo injection of betaine significantly induced positive effects on intestinal morphometry by ameliorating the jejunal villus length, the ratio of villus height to villus width, and absorptive surface area.

Study on the mechanism of vitamin E alleviating non-alcoholic fatty liver function based on non-targeted metabolomics analysis in rats

Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. Vitamin E (VE) has antioxidant properties and can mediate lipid metabolism. Non-targeted metabolomics technology was employed to uncover comprehensively the metabolome of VE in NAFLD rats. NAFLD model was created with a high-fat and high-cholesterol diet (HFD) in rats. NAFLD rats in the VE group were given 75 mg/(kg day) VE. The metabolites in the serum of rats were identified via UPLC and Q-TOF/MS analysis. KEGG was applied for the pathway enrichment. VE improved the liver function, lipid metabolism, and oxidative stress in NAFLD rats induced by HFD. Based on the metabolite profile data, 132 differential metabolites were identified between VE group and the HFD group, mainly including pyridoxamine, betaine, and bretylium. According to the KEGG results, biosynthesis of cofactors was a key metabolic pathway of VE in NAFLD rats. VE can alleviate NAFLD induced by HFD, and the underlying mechanism is associated with the biosynthesis of cofactors, mainly including pyridoxine and betaine.

Evaluation of commercial doses of a feed additive and silymarin on broiler performance with and without CCl4-induced liver damage

Improving productive performance is a daily challenge in the poultry industry. Developing cost-effective additives and strategies that improve performance in antibiotic-free poultry production is critical to maintaining productivity and efficiency. This study evaluates the influence of a commercially available phytogenic feed additive (CA-PFA, that comprises silymarin, betaine and curcumin extracts as main ingredients) and silymarin on commercial broilers' productive performance and liver function with and without carbon tetrachloride (CCl4)-induced liver damage. The experiment was conducted in a completely randomized design, with six treatments, eight replicates, and eight birds per replicate in 18 one-day-old male broilers (Cobb Vantress 500) each; under a 3 × 2 factorial arrangement (3 diets x 2 levels of CCl4, 0 and 1 mL/kg body weight orally). The experimental treatments included 3 diets, commercially recommended doses of CA-PFA (500 mg/kg of feed; this dose provides 70 mg/kg of silymarin, besides the other active ingredients included in the formulation), silymarin (250 mg/kg of feed, containing 28% of active ingredient; this dose provides 70 mg/kg of silymarin as active ingredient) and an additive-free basal diet as a control. A standard commercial silymarin was used as a reference due to its well-known and extensively studied hepatoprotective properties that can mitigate the negative effects of CCl4 in the liver. The data were analyzed as a 2-way ANOVA, and the means showing significant (P ≤ 0.05) differences were then compared using the Post-Hoc Tukey HSD test. No interaction was detected between factors. Exposure to CCl4 had a noticeable detrimental effect on alertness, productive performance, and liver function of broilers without a significant increase in mortality. Including CA-PFA in the diet improved productive performance compared to the basal diet from day 21 to the end of the trial, on day 42. While no influence in feed intake was detected for any treatment, CA-PFA improved body weight gain (BWG) and feed conversion ratio (FCR) significantly (P < 0.05) from day 21 to the end of the trial in healthy and CCl4-exposed birds. The results show that CA-PFA supplementation improves performance parameters in broilers with and without CCl4-induced liver damage, when compared to a basal diet and the addition of a standard commercial silymarin product.

Dietary Betaine Supplementation Enhances Colonic Barrier Function through the Nrf2/Keap1 and TLR4-NF-κB/MAPK Signaling Pathways and Alters Colonic Microbiota in Bama Mini-Pigs

This study evaluated the effects of betaine supplementation in sows and/or their offspring's diets on the redox status, immune and inflammatory levels, colonic barrier function, and colonic microbial community of offspring piglets. Thirty-six Bama mini-sows on day 3 of gestation and their weaned offspring piglets (28 d of age) were randomly allocated to the following treatments: (1) sows and their weaned offspring fed the basal diet (control group, Con group); (2) sows fed the basal diet with 3.50 kg/t betaine, and their weaned offspring fed the basal diet (sows betaine group, SB group); (3) sows fed the basal diet with 3.50 kg/t betaine, and their weaned offspring fed the basal diet with 2.50 kg/t betaine (sow-offspring betaine group, S-OB group). Six offspring piglets from each group were selected to collect plasma and colon samples on d 30, 60, and 90 after weaning. Compared with the Con group, the plasma levels of IgA, IgM, GSH-Px, and SOD during d 30-90 after weaning, IFN-α, T-AOC, and GSH on d 30 and 60 after weaning were increased, while MDA during d 30-90 after weaning was decreased in the SB and S-OB groups (p < 0.05). In addition, the plasma levels of IFN-γ on d 60 and T-AOC on d 30 after weaning were higher in the S-OB group than those in the Con group (p < 0.05). In the colon, betaine supplementation increased plasma T-AOC, GSH, and SOD levels while decreasing MDA concentration (p < 0.05). Betaine supplementation improved the colonic protein abundances of ZO-1, occludin, and claudin in offspring and activated the Nrf2/Keap1 signaling pathway while inhibiting the TLR4-NF-κB/MAPK signaling pathway on d 90 after weaning. The 16S rRNA sequencing results showed that betaine supplementation altered colonic microbiota composition by increasing the relative abundances of Verrucomicrobia and Actinobacteria in the SB group while decreasing proinflammatory-associated microbiota abundances (Tenericutes, Prevotella, and Parabacteroides) (p < 0.05). Collectively, these findings suggest that dietary betaine supplementation in sows and/or their offspring could improve offspring piglets' redox status and immune and anti-inflammatory levels and enhance the colonic barrier function by activating Nrf2/Keap1 and inhibiting TLR4-NF-κB/MAPK signaling pathways.

Effect of Dioscorea Opposite Waste Supplementation on Antioxidant Capacity, Immune Response and Rumen Microbiome in Weaned Lambs

Dioscorea opposite waste (DOW) has been shown to improve the gastrointestinal microbiome, antioxidation capacity, and immune activity, indicating it is a potential feed resource to improve the physiological health and rumen function of weaned lambs. In the present study, the responses of rumen microbiome to DOW supplementation in diet were profiled using metagenome sequencing. In addition, the potential of DOW to regulate plasma parameters in weaned lambs and its possible mechanisms were investigated. Sixty healthy male small tail Han lambs (22.68 ± 2.56 kg) were selected and equally assigned to four dietary treatments: (1) DOW-free diet (CON), (2) addition of 10% DOW diet (DOW1), (3) addition of 15% DOW diet (DOW2), and (4) addition of 20% DOW diet (DOW3). Experimental lambs were fed a corresponding diet for 62 days. Rumen microbiome and plasma parameters were determined at the end of the experiment. The results showed that dietary supplementation with DOW linearly increased the concentration of aspartate aminotransferase, alkaline phosphatase, Immunoglobulin A, Immunoglobulin M, Immunoglobulin G, Glutathione peroxidase, Superoxide dismutase, and total antioxidant capacity in the plasma of weaned lambs, but an opposite trend was observed in Interleukin-1β, Interleukin-6, tumor necrosis factor-α, and Malondialdehyde between the DOW-supplemented group and the CON group. Sequencing of rumen metagenome revealed that dietary supplementation with 20% DOW significantly affected the microbial composition and function and increased the richness and diversity of rumen microbiota and relative abundance of phylum Verrucomicrobia, Planctomycetes, Fibrobacteres, Chloroflexi, Actinobacteria, and Acidobacteria and species Ruminococcaceae_bacterium, Clostridiales_bacterium_NK3B98, Clostridiales_bacterium, and Clostridia_bacterium. It was concluded that supplementing the weaned lamb’s ration with DOW increased the immune response and antioxidant capacity in a dose-dependent manner. Meanwhile, dietary supplementation with 20% DOW modulated the composition of rumen microbiome function by increasing Ruminococcaceae_bacterium and Clostridiales_bacterium with improving the polysaccharide hydrolase activity in the rumen.

Effects of emulsifier, betaine, and L-carnitine on growth performance, immune response, gut morphology, and nutrient digestibility in broiler chickens exposed to cyclic heat stress

1. This experiment investigated the efficacy of varying doses of an emulsifier blend (EB; 0 and 1 g/kg of diet), betaine (BT; 0 and 1 g/kg of diet) and L-carnitine (CT; 0 and 0.5 g/kg of diet) in broilers subjected to circular heat stress (HS) conditions. A total of 1080 one-day-old male broiler chickens (Ross 308) were randomly assigned to one of nine treatment groups (six pens/treatment with 20 birds/pen) according to a completely randomised design. The thermoneutral control broiler chickens were housed at a comfortable temperature and fed a standard diet (no additives). The other eight groups were exposed to cyclic HS conditions (34°C) for 8 h (10:00-18:00).2. There were EB × BT × CT interactions for body weight (BW) at 24 d (P = 0.038) and average daily gain (ADG) during the 10-24 d period (P = 0.049), with the greatest values found with concurrent supplementation of three supplements.3. Inclusion of EB resulted in greater (P < 0.05) BW, ADG, European performance index, uniformity rate, primary antibody titres against sheep red blood cells (SRBC), duodenal villus height (VH) and villus surface area, digestible energy (DE) and the coefficient of apparent ileal digestibility (CAID) of dry matter, crude protein, and fat However, feed conversion ratio, mortality rate and heterophile to lymphocyte ratio were lower (P < 0.05).4. Dietary BT supplementation improved (P < 0.05) all performance indicators, primary antibody titres against SRBC and Newcastle disease virus, serum total antioxidant capacity, duodenal VH, Jejunal VH/crypt depth and the CAID of dry matter and crude protein. The effect of dietary supplementation with CT was limited to an increase (P < 0.05) in ADG (d 10-24) and a decrease (P < 0.05) in serum malondialdehyde concentration (42 d) and jejunal crypt depth (42 d).5. In conclusion, dietary supplementation of either EB or BT alone or in combination ameliorated some of the detrimental effects of HS on growth performance, immunity and intestinal health in broilers, while a minor positive effect on performance and antioxidant status was observed with CT supplementation.

Comparative Analysis of the Temporal Impacts of Corticosterone and Simulated Production Stressors on the Metabolome of Broiler Chickens

The impact of physiological stress on the metabolome of breast muscle, liver, kidney, and hippocampus was investigated in Ross 308 broiler chicks. Simulated on-farm stressors were compared to a corticosterone model of physiological stress. The three different stressors investigated were: (i) corticosterone at a dose of 15 mg/kg of feed; (ii) heat treatment of 36 °C and 40% RH for 8 h per day; and (iii) isolation for 1 h per day. Liver, kidney, breast muscle, and hippocampus samples were taken after 2, 4, 6, and 8 days of stress treatment, and subjected to untargeted ¹H-nuclear magnetic resonance (NMR) spectroscopy-based metabolomic analysis to provide insights on how stress can modulate metabolite profiles and biomarker discovery. Many of the metabolites that were significantly altered in tissues were amino acids, with glycine and alanine showing promise as candidate biomarkers of stress. Corticosterone was shown to significantly alter alanine, aspartate, and glutamate metabolism in the liver, breast, and hippocampus, while isolation altered the same pathways, but only in the kidneys and hippocampus. Isolation also significantly altered the glycine, serine, and threonine metabolism pathway in the liver and breast, while the same pathway was significantly altered by heat in the liver, kidneys, and hippocampus. The study's findings support corticosterone as a model of stress. Moreover, a number of potential metabolite biomarkers were identified in chicken tissues, which may allow producers to effectively monitor stress and to objectively develop and evaluate on-farm mitigations, including practices that reduce stress and enhance bird health.

Betaine: A Potential Nutritional Metabolite in the Poultry Industry

Poultry industry has been recognized as a fast-developing sector aiming to produce low-cost and high-nutrient foods for human consumption. This review article aimed to focus on the significant roles of dietary betaine supplementation in the poultry industry. In this respect, different effects of betaine on performance and carcass traits, as well as its osmoregulatory, anticoccidial, immune-modulatory, and heat-stress alleviation activities, were discussed. Different concentrations of betaine supplementation can improve the feed conversion ratio, final body weight, breast muscle yield, egg production ratio, and reduce body fat contents in broiler chicken, turkey, duck, geese, and quail diets. Betaine supplemented with methyl groups can eliminate the need to have some methyl-group donors, including choline and methionine, therefore having positive effects on feed conversion ratio in poultry diets. The osmolytic character of betaine can alleviate heat stress and have a positive impact on tonic immobility, which consequently reduces stress in poultry. By inhibiting distinct developmental stages of Eimeria species, betaine reduces the damaging effects of coccidiosis on broiler chickens and improves intestinal structure and function. The immunological, cardiovascular, neurological, renal, and hepatic metabolic systems benefit from betaine's osmo-protective properties. Therefore, betaine has the potential to be considered as an alternative to feed additives and enhances the health status and productive performance of poultry.

RETRACTED ARTICLE: Effects of emulsifier, betaine, and L-carnitine on growth performance, immune response, gut morphology, and nutrient digestibility in broiler chickens exposed to cyclic heat stress

1. This experiment investigated the efficiency of varying doses of an emulsifier blend (EB; 0 and 1 g/kg of diet), betaine (BT; 0 and 1 g/kg of diet) and L-carnitine (CT; 0 and 0.5 g/kg of diet) in broilers subjected to circular heat stress (HS) conditions.2. A total of 1080 one-day-old male broiler chickens (Ross 308) were randomly assigned to nine treatment groups (six pens/treatment with 20 birds/pen) in a completely randomised design. The thermoneutral control broiler chickens were housed at a comfortable temperature and fed a standard diet (no additives). The other 8 groups were exposed to cyclic HS conditions (34°C) for 8 h (10:00-18:00).3. There were EB × BT × CT interactions for body weight (BW) at 24 d (P=0.038) and average daily gain (ADG) during the 10-24 d period (P=0.049), with the greatest values with concurrent supplementation of all three ingredients.4. Inclusion of EB resulted in greater (P<0.05) BW, ADG, European performance index, uniformity rate, primary antibody titres against sheep red blood cells (SRBC), duodenal villus height (VH) and villus surface area, nitrogen-corrected apparent metabolisable energy (AMEn) and apparent ileal digestibility (AID) of dry matter, crude protein and fat, but lower (P<0.05) feed conversion ratio, mortality rate and heterophile to lymphocyte ratio.5. Dietary BT supplementation improved (P<0.05) overall performance indicators, primary antibody titres against SRBC and Newcastle disease virus, serum total antioxidant capacity, duodenal VH, Jejunal VH/crypt depth, AID of dry matter and crude protein. The effect of dietary supplementation with CT was limited to an increase (P<0.05) in ADG (d 10-24) and a decrease (P<0.05) in serum malondialdehyde concentration (42 d) and jejunal crypt depth (42 d).6. In conclusion, dietary supplementation of either EB or BT alone or in combination can ameliorate some of the detrimental effects of HS on growth performance, immunity and intestinal health in broilers, while a minor positive effect on performance and antioxidant status was observed with CT supplementation.

Dietary Betaine and Fatty Acids Change Circulating Single-Carbon Metabolites and Fatty Acids in the Dog

In order to evaluate the interaction of betaine and n-3 PUFA in foods consumed by the dog, six extruded dry foods were formulated. The control food had no specific source of added betaine or n-3 fatty acids, while the test foods were supplemented with betaine, flax or fish oil in a 2 × 3 factorial design (no added n-3 source, added flax, added menhaden fish oil, and all with or without added betaine). Forty eight adult dogs were used in this study. All dogs were assigned to one of the six dietary treatments and consumed that food for the length of the 60-day study. Blood was analyzed for metabolomics (plasma), fatty acids and selected health-related analytes (serum) at the beginning and the end of the study. Added dietary betaine increased single-carbon metabolites (betaine, dimethyl glycine, methionine and N-methylalanine), decreased xenobiotics (stachydrine, N-acetyl-S-allyl-L-cysteine, 4-vinylguaiacol sulfate, pyrraline, 3-indoleglyoxylic acid, N-methylpipecolate and ectoine) and enhanced the production of eicosapentaenoic acid (EPA). Dietary betaine also decreased the concentration of circulating carnitine and a number of carnitine-containing moieties. The addition of the n-3 fatty acids alpha-linolenic, EPA and docosahexaenoic acid (DHA) increased their respective circulating concentrations as well as those of many subsequent moieties containing these fatty acids. The addition of alpha-linolenic acid increased the concentration of EPA when expressed as a ratio of EPA consumed.

In ovo injection of betaine promotes adrenal steroidogenesis in pre-hatched chicken fetuses

Corticosterone is critical for the maturation and survival of chicken fetus around hatching. Betaine is used as a feed additive in poultry industry to promote growth and mitigate stress. However, it remains unknown whether betaine could affect adrenal corticosterone synthesis in pre-hatching chicken fetuses. In this study, betaine (2.5 mg/egg) was injected into developing chicken fetuses at d 11 of incubation (E11) and its impact on adrenal steroidogenesis was investigated at day 19 (E19). Plasma corticosterone concentration was significantly (P < 0.05) elevated in betaine-treated fetuses, together with increased adrenal expression of melanocortin 2 receptor and steroidogenic acute regulatory protein. Accordingly, the corticosterone biosynthetic enzymes, such as cytochrome P450 family 11 subfamily A member 1, 3β-hydroxysteroid dehydrogenase and cytochrome P450 family 21 subfamily A member 2, as well as cholesterol biosynthesis or regulation-related genes, such as sterol regulatory element-binding protein 1, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase and low-density lipoprotein receptor, were all significantly (P < 0.05) upregulated in betaine group. Meanwhile, steroidogenic factor-1 and glucocorticoid receptor were significantly (P < 0.05) enhanced, whereas expression of dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome gene, a nuclear receptor known as a repressor of adrenal steroidogenesis, was significantly (P < 0.05) downregulated. Betaine significantly (P < 0.05) increased adrenal expression of genes involved in one-carbon metabolism and DNA methylation, such as S-adenosyl homocysteine hydrolase, betaine-homocysteine-methyltransferase, methionine adenosyl transferase and DNA methyltransferases, yet the promoter regions of most steroidogenic genes were significantly (P < 0.05) hypomethylated. These results indicate that in ovo injection of betaine promotes adrenal glucocorticoid synthesis in chicken fetuses before hatching, which involves alterations in DNA methylation.