Impact of drinking water supplemented 2-hydroxy-4-methylthiobutyric acid in combination with acidifier on performance, intestinal development, and microflora in broilers

Effects of organic acid blends on the growth performance, intestinal morphology, microbiota, and serum lipid parameters of broiler chickens

Organic acids have emerged as promising alternatives to antibiotic growth promoters in poultry production. The present study was conducted to determine the effects of organic acids blends v.i.z. Acidapure liquid and Acidapure powder supplementation on the growth performance, gut health, gut microbiota, and serum lipid profile of broiler chickens. A total of 120-day-old chicks with similar live body weights were randomly divided into four groups. Each group was further divided into 3 replicates, and each further divided into three replicates of ten bird. The birds in Group 1 (T1) were fed a basal diet supplemented with plain drinking water, those in Group 2 (T2) received basal feed supplemented with Acidapure powder (1 kg/MT feed) and plain drinking water, those in Group 3 (T3) received basal feed supplemented with Acidapure liquid in the drinking water (0.2 ml/l water), and those in Group 4 (T4) received basal feed supplemented with Acidapure powder (1 kg/MT feed) and Acidapure liquid in the drinking water (0.2 ml/l water). Acidapure powder and Acidapure liquid were added to the feed and water of the broilers from 0-42 days of life. The results showed that compared with the control (T1), supplementation with Acidapure powder and liquid in broiler chickens for 42 days increased (P < 0.05) ABW and ADG and reduced FCR in the treatment groups (T2, T3 and T4). At d 21 and 42, all forms of Acidapure supplement increased the VH and CD in the jejunum and ileum and reduced the pH of the ileum. Compared with the control (T1), the combination of Acidapure powder and liquid (T4) increased the gene expression of the tight junction proteins Claudin-1 and Zona Occludense 1 (ZO-1). Compared with the control, Acidapure supplementation reduced the cecal coliform count and total viable count (TVC) and decreased the serum cholesterol and triglyceride levels. In conclusion, Acidapure, as a blend of organic acids, effectively enhances the growth performance and gut health of broilers, making it a viable and safe alternative to traditional antimicrobial growth promoters.

Dietary Tributyrin Improves Growth Performance, Meat Quality, Muscle Oxidative Status, and Gut Microbiota in Taihe Silky Fowls under Cyclic Heat Stress

Heat stress adversely affects poultry production and meat quality, leading to economic losses. This study aimed to investigate the effects of adding tributyrin on growth performance, meat quality, muscle oxidative status, and gut microbiota of Taihe silky fowls under cyclic heat stress (CHS) conditions. In this study, 120-day-old Taihe silky fowls (male) were randomly divided into six dietary treatments. These treatments included a normal control treatment (NC, fed a basal diet), a heat stress control treatment (HS, fed a basal diet), and HS control treatments supplemented with 0.04%, 0.08%, 0.16%, and 0.32% tributyrin, respectively. The NC treatment group was kept at 24 ± 1 °C, while the HS treatment birds were exposed to 34 ± 1 °C for 8 h/d for 4 weeks. Results showed that CHS decreased growth performance and compromised the meat quality of broilers (p < 0.05). However, tributyrin supplementation improved ADG and FCR in broilers exposed to CHS (p < 0.05). Additionally, tributyrin supplementation resulted in increased shear force value and GSH-Px activity, as well as a decrease in drip loss, ether extract content, and MDA content of the breast muscle in broilers under CHS (p < 0.05). Furthermore, tributyrin supplementation up-regulated the mRNA expressions of Nrf2, NQO1, HO-1, SOD, and GSH-Px of the breast muscle in broilers exposed to CHS (p < 0.05). Based on these positive effects, the study delved deeper to investigate the impact of 0.16% tributyrin supplementation (HS + 0.16%T) on the cecum microbiota. The HS + 0.16%T treatment showed an increase in the relative abundance of Rikenellaceae_RC9_gut_group (p < 0.05) and a trend towards an increase in Lactobacillus (p = 0.096) compared to the HS treatment. The results indicate that supplementation successfully improved the growth performance and meat quality of Taihe silky fowls. Furthermore, tributyrin supplementation, particularly at levels of 0.16%, improved meat quality by enhancing muscle antioxidant capacity, which is believed to be associated with activation of the Nrf2 signaling pathway.

Bacillus subtilis JATP3 improved the immunity of weaned piglets by improving intestinal flora and producing citalopram

The purpose of this study was to evaluate the ability of Bacillus subtilis JATP3 to stimulate immune response and improve intestinal health in piglets during the critical weaning period. Twelve 28-day-old weaned piglets were randomly divided into two groups. One group was fed a basal diet, while the other group was fed a basal diet supplemented with B. subtilis JATP3 (1 × 109 CFU/mL; 10 mL) for 28 days. The results revealed a significant increase in the intestinal villus gland ratio of weaned piglets following the inclusion of B. subtilis JATP3 (P < 0.05). Inclusion of a probiotic supplement improve the intestinal flora of jejunum and ileum of weaned piglets. Metabolomics analysis demonstrated a notable rise in citalopram levels in the jejunum and ileum, along with elevated levels of isobutyric acid and isocitric acid in the ileum. The results of correlation analysis show that indicated a positive correlation between citalopram and microbial changes. Furthermore, the probiotic-treated group exhibited a significant upregulation in the relative expression of Claudin, Zonula Occludens 1 (ZO-1), and Interleukin 10 (IL-10) in the jejunum and ileum, while displaying a noteworthy reduction in the relative expression of Interleukin 1β (IL-1β). Overall, these findings suggest that B. subtilis JATP3 can safeguard intestinal health by modulating the structure of the intestinal microbiota and their metabolites, wherein citalopram might be a key component contributing to the therapeutic effects of B. subtilis JATP3.

Methionine Source and Level Modulate Gut pH, Amino Acid Transporters and Metabolism Related Genes in Broiler Chickens

This study determined the effects of two methionine (Met) sources at three total sulfur amino acids (TSAA) to lysine ratios (TSAA/Lys) on gut pH, digestive enzyme activity, amino acid transporter expression, and Met metabolism of broilers. The birds were randomly assigned to a 2 × 3 factorial arrangement with Met sources (dl-Met and dl-2-hydroxy-4-(methylthio)-butanoic acid (OH-Met)) and TSAA/Lys (0.58, 0.73, and 0.88) from 1 to 21 days. The results demonstrated that dl-Met and OH-Met supported the same growth performance, but high TSAA/Lys ratio reduced the feed intake and body weight (P < 0.05). OH-Met reduced the crop chyme pH and enhanced the jejunal lipase activity (P < 0.05). ATB0,+ expression decreased with increased dl-Met levels in the duodenum; the low TSAA/Lys ratio induced a stronger mRNA expression of basolateral Met transporters. OH-Met resulted in an increase of cystathionine β-synthase expression in the liver and a decrease in serum homocysteine levels at middle TSAA/Lys ratio compared with dl-Met treatment (P < 0.05). In conclusion, two Met sources support the same growth, but OH-Met acidified the crop chyme. The investigated transporter transcripts differed significantly along the small intestine. At the middle TSAA/Lys ratio, OH-Met showed a higher metabolic tendency of the trans-sulfuration pathway compared with dl-Met.

Modeling the influence of propionic acid concentration and pH on the kinetics of Salmonella Typhimurium

Salmonella Typhimurium is a foodborne pathogen often found in the poultry production chain. Antibiotics have been used to reduce S. Typhimurium contamination in poultry aviaries and improve chicken growth. However, antibiotics were banned in several countries. Alternatively, organic acids, such as propionic acid (PA), can control pathogens. This study determined the PA minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and mathematically modeled S. Typhimurium growth/inactivation kinetics under the influence of PA at different pH values (4.5, 5.5, and 6.5) which are within the pH range of the chicken gastrointestinal tract. The PA MIC against S. Typhimurium was pH-dependent, resulting in 5.0, 3.5 and 9.0 mM undissociated PA at pH 4.5, 5.5, and 6.5, respectively. The Baranyi and Roberts and the Weibull model fit growth and inactivation data well, respectively. Secondary models were proposed. The validated model predicted 3-log reduction of S. Typhimurium in 3 h at 68.2 mM of undissociated PA and pH 4.5. The models presented a good capacity to describe the kinetics of S. Typhimurium subjected to PA, representing a useful tool to predict PA antibacterial action depending on the pH.

Effects of coated sodium butyrate on the growth performance, serum biochemistry, antioxidant capacity, intestinal morphology, and intestinal microbiota of broiler chickens

Introduction

This study examined the impact of adding coated sodium butyrate (CSB) to the diet on the growth performance, serum biochemistry, antioxidant capacity, intestinal morphology, and cecal microbiota of yellow-feathered broiler chickens.

Methods

In this study, 240 yellow-feathered broiler chickens at 26 days old were divided into two groups: the control group (CON group) received a standard diet, and the experimental group (CSB group) received a diet with 0.5 g/kg of a supplement called CSB. Each group had 6 replicates, with 20 chickens in each replicate, and the experiment lasted for 36 days.

Results

Compared to the CON group, the CSB group showed a slight but insignificant increase in average daily weight gain during the 26-62 day period, while feed intake significantly decreased. The CSB group exhibited significant increases in serum superoxide dismutase, catalase, and total antioxidant capacity. Additionally, the CSB group had significant increases in total protein and albumin content, as well as a significant decrease in blood ammonia levels. Compared to the CON group, the CSB group had significantly increased small intestine villus height and significantly decreased jejunal crypt depth. The abundance of Bacteroidetes and Bacteroides in the cecal microbiota of the CSB group was significantly higher than that of the CON group, while the abundance of Proteobacteria, Deferribacteres, and Epsilonbacteraeota was significantly lower than that of the CON group.

Conclusion

These results suggest that adding CSB to the diet can improve the growth performance and antioxidant capacity of yellow-feathered broiler chickens while maintaining intestinal health.

Modulation of Performance, Plasma Constituents, Small Intestinal Morphology, and Cecum Microbiota in Growing Geese by Dietary Citric Acid Supplementation

To investigate the efficiency and optimum inclusion level of CA in growing geese diets on performance, plasma constituents, and intestinal health, 240 healthy female geese at the age of 28d were randomly allotted six treatment diets incorporated with 0, 0.8, 1.6, 2.4, 3.2, and 4% CA. Each treatment group consisted of five replicates and eight birds per replicate. The findings demonstrated that 3.2% CA supplementation resulted in improved growth performance (ADG, ADFI, and FBW) (p = 0.001), and geese who received CA also showed lower body fat contents (p < 0.05) than the control group. Moreover, geese from the 2.4% and 3.2% CA group had the highest plasma glutathione peroxidase and insulin-like growth factor 1 levels compared to the other groups (p < 0.05). A microbial diversity analysis of the cecum conducted by 16S rDNA sequencing revealed that 3.2% CA supplementation showed a significantly higher abundance of beneficial bacteria (Muribaculaceae, CHKCI001, Erysipelotricha-ceae_UCG_003, and UCG_009) (p < 0.05) and a lower abundance of harmful bacteria (Atopobiaceae, Streptococcus, Acinetobacter, Pseudomonas, and Alistipes) (p < 0.10). Collectively, our results revealed that dietary supplementation with 3.2% CA had several benefits on the performance and physiological health of growing geese by promoting nutrients metabolism, improving antioxidant capacity, and modulating cecum microbiota.

Regulating effects of chlorinated drinking water on cecal microbiota of broiler chicks

In this study, 2 types of drinking water were provided to broiler chicks to evaluate the relationship between the bacterial load of drinking water and cecal microbiota. One type of drinking water was untreated, while the other type was daily treated with sodium dichlorocyanurate (50 mg/L). A total of 240 broiler chicks were divided into 2 groups based on their initial body weight. There were 6 replicates in each group, and each replicate cage contained 20 birds. Each cage was assigned to a different floor of the battery cage. On the final day, water samples were collected from each replicate cage at the opening of the drinking cup height, and one bird was selected from each replicate cage to obtain cecal content samples for measuring microbiota composition using the 16S rRNA technique. We found that drinking water treated with sodium dichlorocyanurate significantly reduced the richness and diversity of microbiota and diminished/disappeared most gram-negative bacteria. Broiler chicks that consumed chlorinated drinking water exhibited changes in the composition of cecal microbiota, with Alistipes serving as the marker species in the cecal content of broiler chicks that consumed untreated water, whereas AF12 served as the marker species in the cecal content of broiler chicks that consumed chlorinated drinking water. Functional prediction using the MetaCyc database and species composition analysis of metabolic pathways showed that changes in 7 metabolic pathways were related to the abundance of Providencia. Therefore, we concluded that chlorinated drinking water reduced the bacterial load in drinking water, thereby altering the cecal microbiota composition and regulating the metabolic activity of broiler chicks.

Sodium dichloroisocyanurate: improving broiler health by reducing harmful microbial levels in the waterline

Sodium dichloroisocyanurate (NaDCC) is commonly used for treating drinking water, industrial water, and wastewater. This study aimed to investigate the potential effects of NaDCC-treated waterline drinking water on the growth of AA+ broilers by reducing microbial levels in the waterline. A total of 480 healthy 1-day-old AA+ broilers (46.77 ± 0.50 g) were selected for the experiment and randomly divided into four groups with six replicates of 20 birds each. The control group received regular drinking water, while the test groups received drinking water with NaDCC concentrations of 10, 30, and 50 mg/L. The test groups consumed the treated water on specific days throughout the 42-day experimental period. Results showed that NaDCC treatment significantly reduced the levels of E. coli, Salmonella, S. aureus and Moulds in the drinking water at the waterline (p < 0.05). Drinking water with NaDCC also led to reduced broiler fecal emissions of NH3 and H2S, as well as reduced counts of E. coli, Salmonella, S. aureus and Moulds (p < 0.05), particularly at 30 mg/L and 50 mg/L concentrations. Broilers consuming NaDCC at 50 mg/L exhibited a significant increase in ADG from days 1-42 (p < 0.05). The levels of E. coli, Salmonella, S. aureus and Moulds in the drinking water at the waterline were significantly and positively correlated with the bacterial count in the feces (p < 0.05, R > 0.6). Additionally, bacterial levels in drinking water and broiler feces were negatively correlated with broiler production performance indicators, including ADG, ADFI, F/G and AWC. In conclusion, NaDCC can indirectly enhance broiler performance by reducing the levels of harmful bacteria in the waterline without affecting normal drinking water. The addition of 30 mg/L or 50 mg/L of NaDCC to the waterline in poultry production can effectively control harmful microorganisms and improve poultry health. Based on the experiment's results, it is recommended to preferentially use 30 mg/L NaDCC in the waterline to reduce farming costs.

Growth performance and cecal microbiota of broiler chicks as affected by drinking water disinfection and/or herbal extract blend supplementation

Environmental exposures during early life are important for animals' intestinal microbiota composition and their production performance. This experiment investigated the growth performance, hematology parameters, jejunal morphology, and cecal microbiota of broiler chicks as affected by exogenous factors from the aspects of drinking water quality and dietary manipulation. A total of 480-day-old broiler chicks (Arbor acre; 41.59 ± 0.88 g) were randomly assigned into 4 groups (CON, HWGM, CA, CAHWGM). Each group had 6 replicates with 20 birds per replicate. Broiler chicks in CON group were fed with basal diet and drank normal drinking water; in HWGM group were fed with basal diet supplemented with 1.5g/kg herbal extract blend (hops, grape seed, and wheat germ) and drank normal drinking water; in CA group were fed with basal diet and drank sodium dichlorocyanurate (50 mg/L) treated-drinking water; in CAHWGM group were fed with basal diet supplemented with 1.5 g/kg herbal extract blend and drank chlorinated drinking water. The experimental period was 42 d. We found that broiler chicks drank chlorinated drinking water led to an increase in body weight gain and feed efficiency during d 22 to 42 and 1 to 42, as well as a decrease in cecal Dysgonomonas and Providencia abundance. Dietary supplementation of herbal extract blend increased cecal Lactobacillus and Enterococcus abundance, whereas decreased Dysgonomonas abundance. Moreover, we observed that cecal Dysgonomonas abundance synergistically decreased by treating drinking water with sodium dichlorocyanurate and supplementing herbal extract blend to the diet. Therefore, results obtained in this study indicated that providing chlorinated drinking water is an effective strategy to improve the growth performance of broiler chicks by regulating intestinal microbiota. Additionally, dietary supplementation of herbal extract blend alone or combined with chlorinated drinking water is able to regulate cecal microbiota.

Effects of bis-chelated copper in growth performance and gut health in broiler chickens subject to coccidiosis vaccination or coccidia challenge

Copper (Cu) is widely used at high levels as growth promoter in poultry, the alternative source of Cu to replace the high level of inorganic Cu at poultry farm remains to be determined. Three floor pen experiments were conducted to evaluate the effects of Cu methionine hydroxy-analogue chelate (Cu-MHAC, MINTREX^®Cu, Novus International, Inc.) on growth performance and gut health in broilers in comparison to CuSO₄ and/or tribasic copper chloride (TBCC). There were 3 treatments in experiment#1 (0, 30 and 75 ppm Cu-MHAC) and experiment#2 (15 and 30 ppm Cu-MHAC, and 125 ppm CuSO₄), and 4 treatments in experiment #3 (15 and 30 ppm Cu-MHAC, 125 ppm CuSO₄ and 125 ppm TBCC) with nine replicates pens of 10-13 birds in each treatment. The levels of other minerals were equal among all treatments within each experiment. All birds were orally gavaged with a coccidiosis vaccine at 1x recommended dose on d0 in experiment#1 and #2 and 10x recommended dose on d15 in experiment #3. Data were analyzed by one-way ANOVA, means were separated by Fisher's protected LSD test. A p ≤ 0.05 was considered statistically different. In experiment #1, 30 and 75 ppm Cu-MHAC improved FCR during grower phase, increased jejunal villus height and reduced jejunal crypt depth, 30 ppm Cu-MHAC increased cecal Lactobacillus spp. abundance in 41 days broilers. In experiment #2, compared to CuSO₄, 15ppm Cu-MHAC increased cumulative performance index in 28 days broilers, 15 and/or 30 ppm Cu-MHAC improved gut morphometry, and 30 ppm Cu-MHAC reduced the abundance of E. coli and Enterobacteriaceae in cecum in 43 days broilers. In experiment #3, 15 ppm and 30 ppm Cu-MHAC improved FCR vs. CuSO₄ during starter phase, reduced the percentage of E. coli of total bacteria vs. TBCC, 30 ppm Cu-MHAC increased the percentages of Lactobacillus acidophilus, Lactobacillus spp. and Clostridium cluster XIVa of total bacteria vs. both CuSO₄ and TBCC in the cecum of 27 days broilers. In summary, low doses of Cu-MHAC had comparable growth performance to high dose of TBCC and CuSO₄ while improving gut microflora and gut morphometry in broilers subject to coccidiosis vaccination or coccidia challenge, indicating that low doses of bis-chelated Cu could be used as a complimentary strategy to improve animal gut health.

Lacticaseibacillus rhamnosus C1 effectively inhibits Penicillium roqueforti: Effects of antimycotic culture supernatant on toxin synthesis and corresponding gene expression

Recently, consumers are increasingly concerned about the contamination of food by molds and the addition of chemical preservatives. As natural and beneficial bacteria, probiotics are a prospective alternative in food conservation because of their antimycotic activities, although the mechanism has not been explained fully at the level of metabolites. This study aimed at investigating the antifungal activities and their mechanisms of five potential probiotic strains (Lacticaseibacillus rhamnosus C1, Lacticaseibacillus casei M8, Lactobacillus amylolyticus L6, Schleiferilactobacillus harbinensis M1, and Limosilactobacillus fermentum M4) against Penicillium roqueforti, the common type of mold growth on the bread. Results showed that C1 emerged the strongest effectiveness at blocking mycelium growth, damaging the morphology of hyphae and microconidia, decreasing DNA content and interfering in the synthesis of the fungal toxins patulin, roquefortine C and PR-toxin, as well as downregulating the expression of key genes associated with the toxin biosynthesis pathways. Further metabonomic investigation revealed that protocatechuic acid with the minimum inhibitory concentration of 0.40 mg/mL, may be most likely responsible for positively correlated with the antimycotic effects of C1. Thus, C1 is expected to be both a potentially greatly efficient and environmental antimycotic for controlling P. roqueforti contamination in foods.

Evaluation of Liquid Organic Acids on the Performance, Chyme pH, Nutrient Utilization, and Gut Microbiota in Broilers under High Stocking Density

This study aimed to evaluate the efficacy of organic acids (OAs) in starter broilers and to investigate whether supplemental OAs could alleviate the high stocking density (HSD) stress condition in grower broilers. A total of 408 1-day-old Arbor Acres broilers were assigned into two groups without or with liquid OAs in the starter phase. In the grower phase, each group in the starter phase was divided into a normal stocking density and an HSD. The OA dose was 0.16% at the starter and grower phases. The results showed that at the starter phase, OAs decreased the chyme pH in gizzard and duodenum and increased the activities of chymotrypsin and α-amylase in the duodenal chyme (p < 0.05). In the grower phase, an HSD decreased the growth performance and the ether extract digestibility (p < 0.01). The supplementation of OAs decreased the chyme pH in the gizzard, proventriculus, and duodenum and increased the lipase and α-amylase activities (p < 0.05). The supplemental OAs increased the dry matter and total phosphorous digestibility and the contents of acetic acids, butyric acids, isovaleric acids, and valeric acids (p < 0.05). For cecal microbial compositions at the genus level, an HSD decreased the relative abundance of Blautia, Norank_f__norank_o__RF39, and Alistipes, while supplemental OAs increased the relative abundance of Norank_f__norank_o__RF39 (p < 0.05). In conclusion, although there were no interaction effects between OAs and stocking densities in the present study, it was clear that the supplementation of OAs has beneficial effects on the chyme pH, enzymes activities, and nutrient digestibility in broilers, while an HSD existed adverse effects on the growth performance, nutrient digestibility, and gut microbiota balance in grower broilers.

The effect of acidifier supplementation on egg production performance and intestinal histology of Japanese quail (Coturnix japonica)

BACKGROUND

Acidifier are substances with antibacterial, antifungal, antimicrobial, performance and health benefits that are frequently employed in feed acidification, especially in poultry diet. Meanwhile, the most important factor for acidifier efficiency is the proportion of different acids in the final product.

OBJECTIVES

This study aimed to investigate the effect of dietary supplementation of a commercial acidifier on egg production and histology of the small intestine in laying Japanese quail.

METHODS

One-hundred and sixty female quails at 15 weeks of age were divided into four groups and fed basal diet supplemented with different levels of acidifier (0, 1, 2 and 3 gr acidifier/kg of basal diet) for 8 weeks. Egg production, egg quality attributes and body weight (BW) were measured every 2 weeks. Histology of the small intestine and bacterial population of cecum as well as pH of crop, duodenum, jejunum, ileum and cecum contents were also investigated at the end of the experiment.

RESULTS

Feed conversion ratio (FCR), yolk height, shell thickness, pH of the duodenum, jejunum, ileum, cecum; duodenum, villus width (VW), villus height (VH), crypt depth (CD); jejunum VH, VW and ileum VH to CD ratio (VCR) were linearly improved by the increasing levels of acidifier supplementation (P < 0.05). Duodenum VH increased in a linear and quadratic manner in response to increasing levels of acidifier. Egg weight, yolk diameter, jejunum CD, ileum CD, ileum VW, duodenum CD and jejunum VCR quadratically improved by grading levels of acidifier (P < 0.01). BW, albumen height, Haugh unit, ileum VH and ileum VCR were cubically enhanced (P < 0.05). Acidifier supplementation enhanced egg production, FCR, jejunum, ileum and cecum pH and VH, CD and VW of duodenum and jejunum, compared to the control group (P < 0.05); however, dietary acidifier did not affect egg mass, gizzard pH, ileum VH and bacterial count of the cecum (P > 0.05).

CONCLUSIONS

In conclusion, as calculated, the supplementation of 1 and 2.6 g acidifier per kg of diet was associated with beneficial effects on egg production and quality, gastrointestinal tract pH and histology of the small intestine in laying quails.

Bio-Fermented Malic Acid Facilitates the Production of High-Quality Chicken via Enhancing Muscle Antioxidant Capacity of Broilers

Malic acid, an intermediate of the tricarboxylic acid (TCA) cycle, is a promising acidifier with strong antioxidant capacity. This study aimed to evaluate the effects of bio-fermented malic acid (BFMA) on promoting the body health, performance and meat quality of broilers. A total of 288 one-day-old Arbor Acres male broiler chicks were randomly divided into four treatments with six replicates in each. Every replicate had 12 chicks. Four experimental diets contained 0, 4, 8, and 12 g/kg BFMA, respectively. During the 42-day trial, mortality was recorded daily, feed intake and body weight of each replicate being recorded every week. Blood samples were collected on days 21 and 42 for chemical analysis. After slaughter at the age of 42 days, the carcass traits and meat quality of the broilers were measured, breast muscle samples were collected for the determination of antioxidant capacity, and cecal digesta were pretreated for microbiota analysis. Dietary BFMA significantly increased feed intake and daily gain, and decreased feed conversion ratio and death and culling ratio of the broilers at the earlier stage. The water-holding capacity of breast muscle indicated by the indexes of dripping loss and cooking loss was significantly increased by BFMA, especially at the addition level of 8 g/kg. Dietary BFMA significantly decreased the activity of superoxide dismutase and contents of immunoglobulin A and glutathione, and increased contents of immunoglobulin G and M in serum of the broilers. The contents of glutathione, inosinic acid, and total antioxidant capacity and the activities of glutathione-Px and superoxide dismutase were significantly increased by dietary BFMA, with the level of 8 g/kg best. The diversity of cecal microbiota of broilers was obviously altered by BFMA. In conclusion, as one of several acidifiers, addition of BFMA in diets could improve the performance and body health of broilers, probably by reinforcing immunity and perfecting cecal microbiota structure. As one of the intermediates of the TCA cycle, BFMA increases the water-holding capacity of breast muscle of broilers, probably through reducing lactate accumulates and enhancing antioxidant capacity.

Insights in the Development and Uses of Alternatives to Antibiotic Growth Promoters in Poultry and Swine Production

The overuse and misuse of antibiotics has contributed to the rise and spread of multidrug-resistant bacteria. To address this global public health threat, many countries have restricted the use of antibiotics as growth promoters and promoted the development of alternatives to antibiotics in human and veterinary medicine and animal farming. In food-animal production, acidifiers, bacteriophages, enzymes, phytochemicals, probiotics, prebiotics, and antimicrobial peptides have shown hallmarks as alternatives to antibiotics. This review reports the current state of these alternatives as growth-promoting factors for poultry and swine production and describes their mode of action. Recent findings on their usefulness and the factors that presently hinder their broader use in animal food production are identified by SWOT (strength, weakness, opportunity, and threat) analysis. The potential for resistance development as well as co- and cross-resistance with currently used antibiotics is also discussed. Using predetermined keywords, we searched specialized databases including Scopus, Web of Science, and Google Scholar. Antibiotic resistance cannot be stopped, but its spreading can certainly be hindered or delayed with the development of more alternatives with innovative modes of action and a wise and careful use of antimicrobials in a One Health approach.