Effects of supplementation level and feeding schedule of butyrate glycerides on the growth performance and carcass composition of broiler chickens

Effects of Probiotic Lactiplantibacillus plantarum HJLP-1 on Growth Performance, Selected Antioxidant Capacity, Immune Function Indices in the Serum, and Cecal Microbiota in Broiler Chicken

This research study aimed to investigate the effects of Lactiplantibacillus plantarum (L. plantarum) on growth performance, oxidation resistance, immunity, and cecal microbiota in broilers. This work classed three hundred and sixty 1-day-old male broilers into three groups randomly, including a control group (CON, basal diet) and antibiotic (ANT, 75 mg kg-1 chlortetracycline added into basal diet) and probiotic groups (LP, 5 × 108 CFU kg-1Lactiplantibacillus plantarum HJLP-1 contained within basal diet). Animals were then fed for 42 days, and each group comprised eight replicates with 15 broilers. Compared with CON, L. plantarum supplementation significantly improved the average daily weight gain (AWDG) (p < 0.05) while reducing the feed-gain ratio over the entire supplemental period (p < 0.05). Birds fed L. plantarum had markedly lower serum ammonia and xanthine oxidase levels (p < 0.05) than those in the ANT and CON groups. Significant improvements (p < 0.05) in superoxide dismutase, catalase, and serum IgM and IgY contents in broilers fed L. plantarum were also observed when compared with those in the CON and ANT groups. Both L. plantarum and antibiotics decreased pro-inflammatory factor IL-1β levels significantly (p < 0.05), while only L. plantarum promoted anti-inflammatory factor IL-10 levels in the serum (p < 0.05) compared with CON. L. plantarum (p < 0.05) increased acetic acid and butyric acid concentrations in cecal contents when compared to those in CON and ANT. Among the differences revealed via 16S rRNA analysis, L. plantarum markedly improved the community richness of the cecal microbiota. At the genus level, the butyric acid-producing bacteria Ruminococcus and Lachnospiraceae were found in higher relative abundance in samples of L. plantarum-treated birds. In conclusion, dietary L. plantarum supplementation promoted the growth and health of broilers, likely by inducing a shift in broiler gut microbiota toward short-chain fatty acid (SCFA)-producing bacteria. Therefore, L. plantarum has potential as an alternative to antibiotics in poultry breeding.

Guar gum as galactomannan source induces dysbiosis and reduces performance in broiler chickens and dietary β-mannanase restores the gut homeostasis

Galactomannans are abundant nonstarch polysaccharides in broiler feed ingredients. In broilers, diets with high levels of galactomannans have been associated with innate immune response stimulation, poor zootechnical performance, nutrient and lipid absorption, and excessive digesta viscosity. However, data about its effects on the gut microbiome are scarce. β-Mannanases are enzymes that can hydrolyze β-mannans, resulting in better nutrient utilization. In the current study, we have evaluated the effect of guar gum, a source of galactomannans, supplemented to broiler diets, either with or without β-mannanase supplementation, on the microbiota composition, in an attempt to describe the potential role of the intestinal microbiota in β-mannanase-induced gut health and performance improvements. One-day-old broiler chickens (n = 756) were randomly divided into 3 treatments: control diet, guar gum-supplemented diet (1.7%), or guar gum-supplemented diet + β-mannanase (Hemicell 330 g/ton). The zootechnical performance, gut morphometry, ileal and cecal microbiome, and short-chain fatty acid concentrations were evaluated at different time points. The guar gum supplementation decreased the zootechnical performance, and the β-mannanase supplementation restored performance to control levels. The mannan-rich diet-induced dysbiosis, with marked effects on the cecal microbiota composition. The guar gum-supplemented diet increased the cecal abundance of the genera Lactobacillus, Roseburia, Clostridium sensu stricto 1, and Escherichia-Shigella, and decreased Intestinimonas, Alistipes, Butyricicoccus, and Faecalibacterium. In general, dietary β-mannanase supplementation restored the main microbial shifts induced by guar gum to levels of the control group. In addition, the β-mannanase supplementation reduced cecal isobutyric, isovaleric, valeric acid, and branched-chain fatty acid concentrations as compared to the guar gum-supplemented diet group, suggesting improved protein digestion and reduced cecal protein fermentation. In conclusion, a galactomannan-rich diet impairs zootechnical performance in broilers and results in a diet-induced dysbiosis. β-Mannanase supplementation restored the gut microbiota composition and zootechnical performance to control levels.

Applications of butyric acid in poultry production: the dynamics of gut health, performance, nutrient utilization, egg quality, and osteoporosis

Due to the increasing demand for antibiotic-free livestock products from the consumer side and the ban on the use of antibiotic growth promoters, the poultry feed industry is increasingly interested in developing more alternatives to cope with this problem. Organic acids (butyric acid) have many beneficial effects on poultry health, performance, and egg quality when used in their diet, thus they can be considered for the replacement of antibiotics in livestock production systems. Butyric acid is most efficacious against pathogenic bacteria such as Salmonella spp. and Escherichia coli, and stimulates the population of beneficial gut bacteria. It is a primary energy source for colonocytes and augments the differentiation and maturation of the intestinal cells. Collectively, butyric acid should be considered as an alternative to antibiotic growth promoters, because it reduces pathogenic bacteria and their toxins, enhancing gut health thereby increasing nutrient digestibility, thus leading to improved growth performance and immunity among birds. The possible pathways and mechanisms through which butyric acid enhances gut health and production performance are discussed in this review. Detailed information about the use of butyric acid in poultry and its possible benefits under different conditions are also provided, and the impacts of butyric acid on egg quality and osteoporosis are noted.

Dietary tributyrin intervention improves the carcass traits, organ indices, and blood biomarker profiles in broilers under the isocaloric diets administration

The objective of the current study was to investigate the effect of dietary tributyrin (TB) intervention on carcass traits, visceral and immune organ indices, and blood biomarker profiles in Arbor Acres (AA) broilers under the isocaloric diets administration. A total of 432-day-old healthy AA broiler chickens were assigned to 4 treatments, with 12 replicates per treatment and 9 birds per cage, for 42 d. The dietary treatments were a basal diet (control) and the basal diet supplemented with a TB product (Eucalorie) at doses of 0.50 g/kg (TB1), 1.0 g/kg (TB2), and 2.0 g/kg (TB3). The results showed that dietary TB treatment quadratically improved the average daily gain and average daily feed intake in the second (22–42 d) and overall (0–42 d) feeding periods (P < 0.05) while decreasing the feed conversion ratio in the second feeding period (P < 0.05). Dietary TB treatment improved the carcass traits, as evidenced by a higher eviscerated carcass rate and lower abdominal fat yield than those in the control group (P < 0.05). The breast meat yield rate was quadratically improved in response to dietary TB administration (P < 0.05). Dietary TB treatment improved the kidney, spleen, thymus, and bursa indices (P < 0.05) and reduced the lung indices compared with those in the control group (P < 0.05). In particular, the spleen and thymus indices were improved quadratically in response to dietary TB administration (P < 0.05). Dietary TB treatment improved the white and red blood cell counts, platelet count, hemoglobin and hematocrit at d 21, and platelet count at d 42 (P < 0.05), with those in the TB3 group being most affected. Dietary TB administration quadratically decreased the plasma content of uric acid at both d 21 and d 42 as well as that of creatine kinase at d 42 (P < 0.05), while it quadratically increased the plasma albumin/globulin ratio at both d 21 and d 42 (P < 0.05). Collectively, these results demonstrated that dietary TB intervention improved the growth performance, carcass traits, selected visceral and immune organ indices, and some blood biochemical markers under the isocaloric diets administration, which may facilitate better economic profit returns in poultry industry application.

The Effects of Different Forms of Butyric Acid on the Performance of Turkeys, Carcass Quality, Incidence of Footpad Dermatitis and Economic Efficiency

Simple Summary

Butyric acid is a short-chain organic acid with established antimicrobial properties. It decreases the pH of intestinal digesta and reduces the abundance of pathogenic bacteria, thus indirectly improving the growth performance of birds. In the present study, turkey diets were supplemented with different forms of butyric acid. The efficiency of bird production and carcass dressing percentage were improved when butyric acid glycerides or coated sodium butyrate were added to the diet. An improvement in footpad condition and an increase in the dry matter content of faeces were noted in birds fed experimental diets. The addition of butyric acid in various forms to turkey diets improved the economic efficiency of production. The results of this study suggest that different forms of butyric acid improve production efficiency, carcass traits, and footpad condition in turkeys. Therefore, sodium butyrate, coated sodium butyrate, and butyric acid glycerides can be valuable feed additives in turkey nutrition.

Abstract

The aim of this study was to compare the efficacy of butyric acid glycerides (BAG), sodium butyrate (SB) and coated sodium butyrate (CSB) in turkey nutrition based on the growth performance of birds, carcass yield, meat quality, the dry matter (DM) content of faeces, the incidence of footpad dermatitis (FPD), and economic efficiency. A 105-day experiment was conducted on 400 BIG 6 female turkeys (4 treatments, 5 replications, 20 birds per replication). The addition of CSB and BAG to turkey diets improved the feed conversion ratio (FCR, p ≤ 0.05) and increased the values of the European Efficiency Index (EEI, p ≤ 0.01). The analysed forms of BA in turkey diets increased the concentration of DM in faeces (p ≤ 0.01) and decreased FPD incidence (p ≤ 0.01), which may suggest that all forms of butyrate improved litter quality and inhibit the risk for diarrhoea. The results of this study indicate that all forms of butyric acid can be valuable feed additives in turkey nutrition.

Effects of Dietary Glycerol Monobutyrate Supplementation on Egg Performance, Biochemical Indices, and Gut Microbiota of Aged Hens

This experiment aimed to determine the effect of dietary supplementation with glycerol monobutyrate (GMB) on egg-laying performance, biochemical indicators, and gut microflora at the late stage of laying hens. A total of 252 healthy Dawu Golden Phoenix laying hens with no difference in body weight were selected and randomly divided into two groups: (1) control group (CG), corn-soybean meal diet, (2) 500 mg glycerol monobutyrate/kg added to the basal diet. Six replicates were set up for each treatment group, with 21 birds per replicate. The trial started at week 55 and lasted for 8 weeks. Compared to the control group, the supplementation with GMB increased egg weight (P = 0.03), shell thickness (P = 0.03) and decreased egg breaking rate (P = 0.04). There was no significant difference in egg production rate, feed-to-egg ratio, egg shape index, eggshell strength, and Haugh unit between the two groups. In addition, dietary GMB decreased the levels of aspartate aminotransferase (P = 0.03) and total bilirubin (P = 0.02) in serum, and increased total antioxidant capacity (P = 0.03) and total superoxide dismutase (P = 0.02). However, alpha diversity indices (Ace, Chao1, Shannon, Simpson, goods_coverage, and PD_whole tree) were not different between the two groups. Notably, dietary GMB significantly decreased the abundances of Proteobacteria at the phylum level and the abundances of Enterobacter at the genus level (P &lt; 0.01), but there was no significant difference in the composition of other cecal microbiota. In summary, the present study revealed that supplementation with 500 mg/kg glycerol monobutyrate improved egg weight, eggshell quality, and antioxidant capacity in serum, but its effect on cecal microbiota composition was limited.

Butyrate in combination with forskolin alleviates necrotic enteritis, increases feed efficiency, and improves carcass composition of broilers

BACKGROUND

The emergence of antimicrobial resistance has necessitated the development of effective alternatives to antibiotics for livestock and poultry production. This study investigated a possible synergy between butyrate and forskolin (a natural labdane diterpene) in enhancing innate host defense, barrier function, disease resistance, growth performance, and meat quality of broilers.

METHODS

The expressions of representative genes involved in host defense (AvBD9 and AvBD10), barrier function (MUC2, CLDN1, and TJP1), and inflammation (IL-1β) were measured in chicken HD11 macrophages in response to butyrate and forskolin in the presence or absence of bacterial lipopolysaccharides (LPS). Intestinal lesions and the Clostridium perfringens titers were also assessed in C. perfringens-challenged chickens fed butyrate and forskolin-containing Coleus forskohlii (CF) extract individually or in combination. Furthermore, growth performance and carcass characteristics were evaluated in broilers supplemented with butyrate and the CF extract for 42 d.

RESULTS

Butyrate and forskolin synergistically induced the expressions of AvBD9, AvBD10, and MUC2 in chicken HD11 cells (P < 0.05) and the synergy was maintained in the presence of LPS. Butyrate and forskolin also suppressed LPS-induced IL-1β gene expression in HD11 cells in a synergistic manner (P < 0.05). The two compounds significantly reduced the intestinal lesions of C. perfringens-challenged chickens when combined (P < 0.05), but not individually. Furthermore, butyrate in combination with forskolin-containing CF extract had no influence on weight gain, but significantly reduced feed intake (P < 0.05) with a strong tendency to improve feed efficiency (P = 0.07) in a 42-d feeding trial. Desirably, the butyrate/forskolin combination significantly decreased abdominal fat deposition (P = 0.01) with no impact on the carcass yield, breast meat color, drip loss, or pH of d-42 broilers.

CONCLUSIONS

Butyrate and forskolin has potential to be developed as novel antibiotic alternatives to improve disease resistance, feed efficiency, and carcass composition of broilers.

Effects of a mixture of mono-glycerides of butyric-, capric-, and caprylic acid with chlortetracycline on the growth performance, intestine morphology, and cecal microflora of broiler birds

This study aimed to investigate the effects of a mixture of mono-glycerides of butyric-, capric-, and caprylic acid (MMG) on the growth performance, intestinal morphology, and cecal microflora of broilers. A total of 960 male Arbor Acre broilers were offered basal diets with or without Chlortetracycline additive (CA) at 500 g/t, and MMG at 3,000, 1,000, or 650 g/t, with 8 replicates of 20 birds per treatment. The results confirmed 500 g/t CA with/without 1,000 g/t MMG increased the average daily weight gain (ADG) of birds compared to the control group 1 during the 42-d experimental period (P < 0.05). Comparing to the control group 1, 500 g/t CA with either 650 g or 1,000 g/t MMG or 1,000 g MMG alone increased the ADG of birds during the late growth stage (22–42 d) (P < 0.05). On d 42, the serum triglyceride levels were higher (P < 0.05) in groups supplemented with CA and CA + 1,000 g/t MMG comparing to the control group; while urea nitrogen level was higher in the control group comparing to the rest of treatment groups Compared to the control group 1, 1,000 g/t MMG alone without CA decreased the abundance of Faecalibacterium and Bacteroides but increased the abundance of Escherichia/Shiegella. About 500 g/t CA alone treatment group had higher abundance of Lactobacillus comparing to the rest of groups. In conclusion, dietary supplement with MMG showed beneficial efficacy on the growth and intestinal function of broilers, demonstrating the potential value of MMG to poultry industry. In terms of dosage, the current trial shows that 3,000 g/t (1–21 d) and 1,000 g/t (22–42 d) MMG without CA was the appropriate dietary supplemented rate for broilers. And the mixed use of 500 g/t CA and 1,000 g/t MMG was benefit for broilers at 22 to 42 d.

Butyric and Citric Acids and Their Salts in Poultry Nutrition: Effects on Gut Health and Intestinal Microbiota

Intestinal dysfunction of farm animals, such as intestinal inflammation and altered gut microbiota, is the critical problem affecting animal welfare, performance and farm profitability. China has prohibited the use of antibiotics to improve feed efficiency and growth performance for farm animals, including poultry, in 2020. With the advantages of maintaining gut homeostasis, enhancing digestion, and absorption and modulating gut microbiota, organic acids are regarded as promising antibiotic alternatives. Butyric and citric acids as presentative organic acids positively impact growth performance, welfare, and intestinal health of livestock mainly by reducing pathogenic bacteria and maintaining the gastrointestinal tract (GIT) pH. This review summarizes the discovery of butyric acid (BA), citric acid (CA) and their salt forms, molecular structure and properties, metabolism, biological functions and their applications in poultry nutrition. The research findings about BA, CA and their salts on rats, pigs and humans are also briefly reviewed. Therefore, this review will fill the knowledge gaps of the scientific community and may be of great interest for poultry nutritionists, researchers and feed manufacturers about these two weak organic acids and their effects on intestinal health and gut microbiota community, with the hope of providing safe, healthy and nutrient-rich poultry products to consumers.

Dietary tributyrin improves reproductive performance, antioxidant capacity, and ovary function of broiler breeders

The objective of this experiment was to investigate the influence of dietary tributyrin on reproduction performance and ovary function of broiler breeders with different egg laying rate. Two hundred fifty-six AA broiler breeders (48-wk-old) were allocated to 4 treatment in a 2 × 2 factorial arrangement with the main effects of tributyrin supplementation (0 and 1,000 mg/kg tributyrin [TRI]) and 2 egg laying rate levels (average [AR, 81.01 ± 0.79%] and low [LR, 70.98 ± 0.95%]). The results shown that the LR breeders presented higher egg weight, but lower egg laying rate, qualified egg rate and feed efficiency than the AR breeders (P_(laying) < 0.05). Also, the superoxidase dismutase (SOD) activity in magnum was lower while malondialdehyde (MDA) was higher in ovary and magnum of LR breeders than that in the AR breeders (P_(laying) < 0.05). Dietary supplementation with tributyrin significantly enhanced egg weight (P_(TRI) < 0.05), increased albumen height as well as Haugh unit (HU) in AR breeders (P_{(interaction)} < 0.05), and also had higher total antioxidant capacity (T-AOC) and lower MDA in ovary (P_(TRI) < 0.05). The cell apoptosis rate and proapoptosis related gene expression (caspase 8, 9 and Bax) in the ovary of LR breeders was higher, while anti-apoptosis related gene (Bcl-2) expression were lower in LR breeders when compared with the AR breeders (P_(laying) < 0.05). Dietary supplementation with tributyrin decreased the cell apoptosis rate and downregulated caspase 9 expression in LR breeders (P_{(Interaction)} < 0.05), up-regulated the Bcl-2 expression in both 2 breeders (P_(TRI) < 0.05). These findings suggest that the breeders with lower egg laying rate also characterized by deteriorate ovary function indicated by lower antioxidant capacity and higher cell apoptosis rate. Dietary supplementation with tributyrin increased egg albumen quality, decreased ovarian proapoptosis related gene expression to improve reproductive tract function; and the positive effect on egg albumen quality is more pronounced in average reproductive breeders.

Monoglyceride Blend Reduces Mortality, Improves Nutrient Digestibility, and Intestinal Health in Broilers Subjected to Clinical Necrotic Enteritis Challenge

This study evaluated the potential of monoglyceride blend (MG) and buffered formic acid (FA) as alternatives to antibiotics in the performance and intestinal health of broilers under clinical necrotic enteritis (NE) challenge. A total of 544 as-hatched Ross 308 broiler chicks were randomly distributed to 32-floor pens housing 17 birds per pen. The four treatments were: NC-non-additive control; ZBS-antibiotic group supplemented with zinc bacitracin and salinomycin; MG-additive MG supplementation in the starter phase only; and MGFA-additive MG in starter phase and FA in grower and finisher phases. All birds were challenged with Eimeria spp. and Clostridium perfringens. Results showed that the NC group had lower BWG and higher FCR than the ZBS group in the grower and overall period (p < 0.05). The NC group had higher NE-caused mortality (days 14 to 17) than the ZBS group (p < 0.05). Birds fed MG had lower NE-caused mortality than the NC group (p < 0.05). Birds fed MG had upregulated jejunal tight junction protein1 (TJP1) and immunoglobulin (IgG) on day 16 and improved gross energy digestibility on day 24 than the NC group (p < 0.05). These findings suggest that supplementation of MG may improve intestinal health and protect birds from clinical NE occurrence.

Effects of monobutyrin supplementation on egg production, biochemical indexes, and gut microbiota of broiler breeders

The objective of the present study was to determine the effect of monobutyrin supplementation on egg production, biochemical indexes, and gut microbiota of broiler breeders at the late stage of production. A total of 180 healthy Qingyuan partridge broilers were randomly assigned to 2 groups: 1) corn-soybean meal-based diet and 2) basal diet supplemented with 250 mg monobutyrin/kg. Each treatment group had 6 replicates/cages with 15 birds within each replicate. The experiment started at week 33 and lasted for 8 wk. Egg production rate, feed conversion rate, shell breaking strength, and shell thickness were not different between control and treatment groups. Supplementation of monobutyrin increased egg weight and tended to decrease egg breaking rate of Qingyuan partridge chickens. Supplementation of monobutyrin did not affect any of the biochemical indexes except total protein concentration. The 4 antioxidant parameters measured were not affected either. Alpha diversity indexes (Shannon, Simpson, Chao1, Ace, and Good's Coverage) and composition of cecal microbiota were not affected by monobutyrin supplementation. Overall, supplementation of monobutyrin at 250 mg/kg level improved egg quality, but its effect on cecal microbiota composition was limited.

Low and high concentrations of butyrate regulate fat accumulation in chicken adipocytes via different mechanisms

The present study investigated the effects of varying concentrations of sodium butyrate (SB) on fat accumulation and cell proliferation in chicken adipocytes. High and low serial concentrations of SB used significantly reduced adipocytic fat accumulation. However, they were observed to exhibit differences in cell morphology and distinctions in lipogenic genes expression profiles. At lower concentration (0.01 mM), fat accumulation was decreased with an associated downregulation in the expression of lipogenic genes, which was mediated by free fatty acid receptors (FFARs). Contarily, at higher concentration (1 mM), the fat droplets laden in adipocytes were enlarged, and this was accompanied with activation of lipogenic genes expression. However, the total accumulated fat was also decreased largely due to reduction in cell numbers, which was partially attributable to the reduction in histone deacetylase (HDAC) activity. Animal experiments further indicated that dietary supplementation of lower dose coated SB (0.1% wt/wt) inhibited fat deposition in livers and abdominal fat tissues of broilers, suggesting the potential application of sodium butyrate as feed additive in the regulation of fat deposition.

Dietary tributyrin supplementation and submaximal exercise promote activation of equine satellite cells

Postexercise skeletal muscle repair is dependent on the actions of satellite cells (SCs). The signal(s) responsible for activation of these normally quiescent cells in the horse remain unknown. The objective of the experiment was to determine whether submaximal exercise or tributyrin (TB) supplementation is sufficient to stimulate SC activation. Adult geldings were fed a control diet (n = 6) or a diet containing 0.45% TB (n = 6). After 30 d, the geldings performed a single bout of submaximal exercise. Middle gluteal muscle biopsies and blood were collected on days -1, 1, 3, and 5 relative to exercise. Diet had no effect on any parameter of physical performance. Total RNA isolated from the gluteal muscle of TB fed geldings contained greater (P < 0.05) amounts of myogenin mRNA than controls. Satellite cell isolates from TB supplemented horses had a greater (P = 0.02) percentage of proliferating cell nuclear antigen immunopositive (PCNA+) SC than controls after 48 h in culture. Submaximal exercise was sufficient to increase (P < 0.05) the percentage of PCNA(+) cells in all isolates obtained during recovery period. No change in the amount of gluteal muscle Pax7 mRNA, a lineage marker of SCs, occurred in response to either diet or exercise. Our results indicate that both submaximal exercise and TB prime SCs for activation and cell cycle reentry but are insufficient to cause an increase in Pax7 expression during the recovery period.

Monobutyrin Reduces Liver Cholesterol and Improves Intestinal Barrier Function in Rats Fed High-Fat Diets

Butyric acid has been shown to reduce high-fat diet-related metabolic disturbances and to improve intestinal barrier function due to its potent anti-inflammatory capacity. This study investigates whether a butyric acid ester, monobutyrin (MB) affects lipid profiles and gut barrier function in a dose-response manner in rats fed butter- or lard-based high-fat diets. Four-week-old male Wistar rats were fed butter-based diets containing 0, 0.25, 0.75 and 1.5 MB g/100 g (dry weight basis) or 0.5 glycerol g/100 g, and diets with lard (La) containing 0 and 0.5 MB g/100 g or a low-fat control diet for 3⁻4 weeks. Lipid profiles in blood and liver tissue, intestinal permeability and cecal short-chain fatty acids were examined. The results showed a dose-dependent decrease in liver total cholesterol for 1.5 MB (p < 0.05) and liver triglycerides for 0.75 MB (p < 0.05) and 1.5 MB (p = 0.08) groups compared to the high-fat control group. Furthermore, a lower excretion of mannitol in urine in the 1.5 MB group indicated improved intestinal barrier function. When MB was supplemented in the lard-based diet, serum total cholesterol levels decreased, and total amount of liver high-density lipoprotein-cholesterol increased. Thus, MB dietary supplementation can be effective in counteracting lipid metabolism disturbances and impaired gut barrier function induced by high-fat diets.

Effects of fatty acid glyceride product SILOhealth 104 on the growth performance and carcass composition of broiler chickens

Butyric acid is the primary energy source for colonocytes, and has shown potential as an alternative to in-feed antibiotics, due to its antimicrobial activity and positive effects on production performance traits of broiler chickens. SILOhealth 104 (SILO S.P.A., Florence, Italy) is a commercial product mainly containing mono- and di-glycerides of butyrate with a small portion of propionic, caprylic, capric, and lauric acid mono- and di-glycerides. Its effects on broiler performance and carcass composition have yet to be evaluated. Four-hundred-eighty day-old male Ross 308 birds were divided into different dietary treatment groups with equal starting weights and fed a diet containing 0, 500, 1,000, 2,000, or 3,000 ppm of SILOhealth 104 for 35 days. There were no significant differences in overall average daily gain or feed: gain ratio with the addition of SILOhealth 104 to the diets (P > 0.05). At 5 wk of age, abdominal fat weight was reduced in birds supplemented with SILOhealth 104 in a dose-responsive manner (P < 0.05), while breast muscle weight increased with supplementation, with significant increases in 2,000 ppm and 3,000 ppm birds compared to controls (P < 0.05). A significant reduction in gene expression of both forkhead box protein O4 and myostatin, 2 factors that can inhibit protein synthesis, was found in the breast muscle of all SILOhealth 104 treated birds (P < 0.05). In addition, gene expression in the adipose tissue, including acetyl-CoA carboxylase alpha and lipoprotein lipase, which are associated with lipid metabolism, was significantly decreased and increased, respectively, by the supplementation of SILOhealth 104 (P < 0.05). These data suggest that the components of SILOhealth 104 can positively affect the deposition of muscle, while reducing abdominal fat deposition in broiler chickens.

Implications of butyrate and its derivatives for gut health and animal production

Butyrate is produced by microbial fermentation in the large intestine of humans and animals. It serves as not only a primary nutrient that provides energy to colonocytes, but also a cellular mediator regulating multiple functions of gut cells and beyond, including gene expression, cell differentiation, gut tissue development, immune modulation, oxidative stress reduction, and diarrhea control. Although there are a large number of studies in human medicine using butyrate to treat intestinal disease, the importance of butyrate in maintaining gut health has also attracted significant research attention to its application for animal production, particularly as an alternative to in-feed antibiotics. Due to the difficulties of using butyrate in practice (i.e., offensive odor and absorption in the upper gut), different forms of butyrate, such as sodium butyrate and butyrate glycerides, have been developed and examined for their effects on gut health and growth performance across different species. Butyrate and its derivatives generally demonstrate positive effects on animal production, including enhancement of gut development, control of enteric pathogens, reduction of inflammation, improvement of growth performance (including carcass composition), and modulation of gut microbiota. These benefits are more evident in young animals, and variations in the results have been reported. The present article has critically reviewed recent findings in animal research on butyrate and its derivatives in regard to their effects and mechanisms behind and discussed the implications of these findings for improving animal gut health and production. In addition, significant findings of medical research in humans that are relevant to animal production have been cited.

Dietary tributyrin, an HDAC inhibitor, promotes muscle growth through enhanced terminal differentiation of satellite cells

Muscle growth and repair rely on two main mechanisms - myonuclear accretion and subsequent protein accumulation. Altering the ability of muscle resident stem cells (satellite cells) to progress through their myogenic lineage can have a profound effect on lifetime muscle growth and repair. The use of the histone deacetylase (HDAC) inhibitor, butyrate, has had positive outcomes on the in vitro promotion of satellite cell myogenesis. In animal models, the use of butyrate has had promising results in treating myopathic conditions as well as improving growth efficiency, but the impact of dietary butyrate on satellite cells and muscle growth has not been elucidated. We investigated the impact of tributyrin, a butyrate prodrug, on satellite cell activity and muscle growth in a piglet model. Satellite cells from tributyrin-treated piglets had altered myogenic potential, and piglets receiving tributyrin had a ~40% increase in DNA:protein ratio after 21 days, indicating the potential for enhanced muscle growth. To assess muscle growth potential, piglets were supplemented tributyrin (0.5%) during either the neonatal phase (d1-d21) and/or the nursery phase (d21-d58) in a 2 × 2 factorial design. Piglets who received tributyrin during the neonatal phase had improved growth performance at the end of the study and had a ~10% larger loin eye area and muscle fiber cross-sectional area. Tributyrin treatment in the nursery phase alone did not have a significant effect on muscle growth or feed efficiency. These findings suggest that tributyrin is a potent promoter of muscle growth via altered satellite cell myogenesis.