Use Of Antibiotic Growth Promoters Research Articles

¿What is the role of phytobiotics in animal production?: Benefits, bioavailability, current and future challenges

More and more countries are incorporating new safety, health and food safety regulations, responding to the growing concern about the use of antibiotic growth promoters (APC) in animal production, the scientific community has been forced to seek new alternatives that reduce or replace the use of (APC), with the ability to safeguard public health. Within these alternatives, phytobiotics are considered a very promising option, since they are natural substances made up of complex bioactive compounds. This document reviews the different applications and functionality of phytobiotics in animal production. Firstly, the main effects and mechanism of action are shown, highlighting and explaining their functionality as antioxidants, anti-inflammatory, antimicrobial, growth promoters, improvers of the organoleptic characteristics of foods and reduces the generation of gases that cause the greenhouse effect. Second, notable applications of phytobiotics to different species of zootechnical interest and their effect are reviewed. Finally, their bioavailability and the current and future challenges of phytobiotics are investigated.

Potential of Organic Acids, Essential Oils and Their Blends in Pig Diets as Alternatives to Antibiotic Growth Promoters.

Over the years, the use of management and feeding strategies to enhance pig productivity while minimizing the use of antibiotic growth promoters has grown. Antibiotic growth promoters have been widely used as feed additives to reduce diet-related stress and improve pig performance. However, increasing concern about the consequences of long-term and increased use of antibiotic growth promoters in animal production has led to a paradigm shift towards the use of natural organic alternatives such as plant essential oils and organic acids in pig nutrition to enhance growth. Antibiotic growth promoters endanger human health by allowing multidrug-resistant genes to be transferred horizontally from non-pathogenic to pathogenic bacteria, as well as directly between animals and humans. Scientific research shows that alternative growth promoters such as essential oils and organic acids appear to improve pigs' ability to prevent pathogenic bacteria from colonizing the intestinal system, stabilizing the gut microflora and promoting eubiosis, as well as improving immunity and antioxidant stability. The purpose of this review was to provide an in-depth review of organic acids and essential oils as growth promoters in pig production, as well as their effects on productivity and meat quality. Organic acids and essential oils in pig diets are a safe way to improve pig performance and welfare while producing antibiotic-free pork.

Evaluation of Natural Antimicrobial Substances Blend as a Replacement for Antibiotic Growth Promoters in Broiler Chickens: Enhancing Growth and Managing Intestinal Bacterial Diseases.

In recent years, commercial use of antibiotic growth promoter (AGP) has restrictions due to drug resistance against intestinal pathogenic bacteria: Escherichia coli, Salmonella, and Clostridium perfringens. Currently there is no single non-antibiotic treatment approach that is effective against intestinal illnesses in broiler chicken. Hence, present study aimed to analyze efficacy of blend of natural antimicrobial substances (probiotics, prebiotics, organic acids, and essential oils blend named as AGPR) as replacers of AGPs (BMD and CTC) for promoting growth and controlling bacterial diseases in aforementioned three microbes challenged broiler chickens. Effects of treatments (5) and microbes (3) on growth and health performances in experimental birds were analyzed using two factorial ANOVA. Health performance like pathogen loads, morbidity and mortality was considerably reduced by AGPR. Similarly small intestine villi morphometry, nutrition utilization, serum immune response, and carcass yield, was improved significantly by AGPR equivalent to AGPs. Further, growth performance like body weight gain, feed efficiency was also improved by AGPR compared to control but, non-significantly. Among three microbes, E. coli infections had higher morbidity and mortality rates. It was concluded that AGPR blend could be used to improve growth and control the intestinal bacterial infections in broiler chickens as an alternative for AGPs.

Dietary olive‑garlic extract oil supplementation: influence on performance and haematological indices of broilers

Abstract The use of antibiotic growth promoters in broiler production has been the norm in developing countries, however, the increased rate of antibiotic resistance in humans has resulted in the search for alternatives without negative residual effects. This study investigated the effect of dietary olive garlic extract oil (OGEO) supplementation on the performance and haematological indices of broilers. The experiment lasted for 42 days and broilers were fed varying levels of OGEO‑supplemented diets at the starter (0–21 days) and finisher (22–42 days) phases using two hundred and forty unsexed Ross broilers. Four experimental diets were formulated for the two phases and the diets were designated as diet 1(control (without OGEO)) while diets 2, 3, and 4 were supplemented with OGEO at 1 % (10 g/kg diet) 3 % (30 g/kg diet) and 5 % (50 g/kg diet). Each had four replicates containing fifteen birds per replicate. Performance was measured weekly and haematological indices were determined on days 21 and 42. Data collected were analysed in a one‑way analysis of variance (SAS, 2000) and significant differences were determined using Tukey’s test. Body weight (BW) increased linearly (L) (p = 0.003) and quadratically (Q) (p = 0.006) with dietary supplementation of OGEO at 1 % for broilers on day 21. Similarly, at day 42, BW increased (L, p = 0.006; Q, p = 0.029) for the broiler on the same treatment. Mortality reduced (Q, p = 0.035) for broilers fed 1 % OGEO‑supplemented diet at day 42. At day 21, Packed cell volume (PCV, 47.33 %) (Q, p = 0.033) and mean corpuscular volume (MCV, 130.83pg) (Q, p = 0.008) increased for broilers fed 1 % and 3 % OGEO supplemented diet respectively. Supplementation of OGEO at 3 % increased (Q, p = 0.036) PCV (37.33 %) and haemoglobin (Q, p = 0.021) (137.30 g/L) at day 42. In conclusion, the supplementation of OGEO in the diet of broilers at 1 % resulted in improved WG and reduced mortality. The PCV and haemoglobin of broilers can be increased with the supplementation of OGEO up to 3 % in the diet of broilers; it is thus a suitable alternative to antibiotics for improved performance and immunity.

Current Applications and Future Trends of Dehydrated Lactic Acid Bacteria for Incorporation in Animal Feed Products

Several lactic acid bacteria (LAB) species have been recognized as probiotics and are of considerable interest due to their potential ability to confer health benefits upon consumption. In the animal feed sector, probiotics offer an alternative to the use of antibiotic growth promoters. The preservation and incorporation of probiotics into dry products requires carefully meeting several criteria and overcoming technological challenges to maintain their functionality. Drying is a crucial step in the process, but the probiotic properties of the resulting powder and the final cell viability in the food product are significantly influenced by the type of protective compounds and drying techniques employed. In light of the growing demand for functional animal products, this review focuses on the damages incurred during microorganism dehydration processes for food incorporation, and explores strategies to minimize such damages. It provides an overview of the effects of probiotic products in the animal feed industry, including their incorporation in low-moisture food matrices and key considerations for success. Additionally, it highlights postbiotics as an attractive alternative for live probiotic cells with many technological advantages.

Utilization of certain unconventional feeds in poultry as natural alternatives to curb antimicrobial resistance

Poultry market has been demonstrating emerging potential as an efficient producer of meat with consumption occupying 40.6% of market globally. The requirement of animal protein is anticipated to grow continuously for meeting the requirements by ever-growing human population. To fulfill this demand, the major challenge encountered by poultry breeders was to fasten production in most efficient and economical way. Use of antibiotic growth promoter in feed help in augmenting poultry growth and alter gut microbiota. However, the growing concern of its likely fatal impacts on animal, food safety and on humans for developing microbial resistance; their use was restricted and banned in several countries. With insinuation of ban, several alternatives were explored for having potential growth promoting benefits without hampering the normal gut microbiota. Various phytobiotics, prebiotics, probiotics, organic acids and unconventional feed have positive effects on feed intake, efficiency and play a role as antimicrobial. However, the meager knowledge on availability and potential use of unconventional feeds as potent antimicrobial restricts its application. This review focuses on certain non-conventional feeds rich in specific bioactive compounds, which are attributed to modulate intestinal microbiota, their effects on growth performance and overall health status of poultry. The review aims to serve as a reference for young researchers and poultry industry to recognize alternative feed ingredients to be used as antimicrobial growth promoters minimizing competition between human and animal consumption.

Organic acids, microbiota, gut health and productive response in broilers chickens

Since the middle of the last century, the use of antibiotic growth promoters in feed has improved the performance of several food-producing animal species. However, bacterial resistance to these drugs threatens public health and has led to their prohibition in animal feed. This has increased enteric problems in broilers and consequently the use of antibiotics for therapeutic purposes. In this context, several alternatives to antibiotic growth promoters have been proposed, among them organic acids, which, according to their physical and chemical properties, modify the composition of the intestinal microbiota, whose metabolites, such as short-chain fatty acids, favor the intestinal morphology, physiology, integrity, and immunity, aspects that contribute to maintain the health of this organ and increase the bioavailability of nutrients and, ultimately, to improve the productive response of birds. This review describes the main characteristics of the organic acids commonly used in the poultry industry, their mechanisms of action and their effects, individually, in combinations of organic acids or with bioactive, on the microbiota, their metabolites, and how this affects the intestinal health and productive performance of broilers under different sanitary and environmental conditions, as well as factors that potentially interfere with the activity of organics acids.

Effects of Bioherbal Compounds on Performance and Intestinal Characteristics of Laying Chickens

Since the European Union banned the use of antibiotic growth promoters in poultry feed in 2006 (EC Regulation No 1831/2003), alternative feed additives have been investigated. The purpose of this study was to evaluate the effect of a bioherbal combination of probiotics and phytobiotics as a feed additive in drinking water on the performance and intestinal characteristics of male laying chickens. The study was performed on 200 male laying chickens for 60 days. This research method was a field experiment with a completely randomized design, consisting of four treatments and five replications. The treatments were T0 (drinking water without bioherbal, control), T1 (control + bioherbal code 1 M), T2 (control + bioherbal code 2 H), and T3 (control + bioherbal combination of 1M and 2H). The investigated parameters included growth performance and intestinal profile of the male laying chickens. The addition of bioherbal increased the number of villi in the intestines of the male laying chickens; however, there was no significant difference among other parameters. It can be concluded that the addition of bioherbal code 2H as a feed additive with a composition of herbal leaves can improve the performance and intestinal characteristics of male laying chickens.

In-feed Salmonella-specific phages alter the physiology, intestinal histomorphology, and carcass and meat quality parameters in broiler chickens

The use of antibiotic growth promoters (AGP) in broiler production leads to the emergence of antibiotic-resistant bacterial pathogens. To mitigate this challenge, biocontrol agents such as phages are being investigated as sustainable alternatives to AGP in commercial broiler production systems. This study aims to investigate the effect of different levels of an in-feed encapsulated Salmonella-specific phage cocktail (SPC) on various parameters, including growth performance, blood indices, carcass characteristics, intestinal histomorphology, and meat quality traits in broiler chickens. A total of 400-day-old Ross 308 male chicks (49.84 ± 1.03 g live weight) were reared on five experimental diets. The diets were formulated as follows: 1) a negative control diet without zinc bacitracin and SPC (NC), 2) a positive control diet with 0.5 g/kg zinc bacitracin but without SPC (PC), and 3) NC with 0.075 (SP75), 0.1 (SP100), and 0.175 g/kg SPC (SP175). During the feeding trial, phages were added on days 1 – 2; 11 – 12; 21 – 22; and 29 – 30 for the SPC treatments. Feed intake, bird weight, and blood parameters were determined during the feeding trial. Birds were slaughtered at the end of the feeding trial (5 weeks) to evaluate carcass characteristics, intestinal histomorphology, and meat quality traits. Five-week-old birds reared on SP100 had lower weight gains (555.7 g/bird) than those reared in the other treatment groups (p < 0.05). The inclusion of SPC in diets induced positive quadratic effects on overall feed intake (R2 = 0.169; p = 0.048) and meat chroma (R2 = 0.184; p = 0.024) but resulted in negative quadratic effects for breast weight (R2 = 0.418; p = 0.046) and linear effects for meat pH 1-h post-mortem (R2 = 0.161; p = 0.040) and proventriculus weight (R2 = 0.195; p = 0.024). A positive quadratic effect was noted for duodenal villus height (R2 = 0.935; p = 0.003), width (R2 = 0.882; p = 0.009), and area (R2 = 0.929; p = 0.001); jejunal villus height (R2 = 0.914; p = 0.001), width (R2 = 0.917; p = 0.002), area (R2 = 0.903; p = 0.001), and muscle thickness (R2 = 0.970; p = 0.001); ileal villus width (R2 = 0.747; p = 0.006), and crypt depth (R2 = 0.916; p = 0.001). Compared to the negative control, SPC induced positive changes in the jejunal and ileal villus height and VH:CD, however, this did not improve growth performance of broiler chickens. It can be concluded that periodic SPC inclusion has the potential to replace subtherapeutic antibiotic use in poultry production.

Immunization of broiler chickens with five newly identified surface-exposed proteins unique to Clostridium perfringens causing necrotic enteritis

Since the ban or reduction on the use of antibiotic growth promoters (AGPs) in commercial broiler chickens in many countries, avian necrotic enteritis (NE) caused by Clostridium perfringens has re-emerged as one of the biggest threats for the poultry industry worldwide. While the toolbox for controlling NE in the absence of antibiotics consists of a limited number of alternatives for which the overall effectiveness has yet proven to be suboptimal, an effective vaccine would represent the best control strategy for this often-deadly disease. Using a comparative and subtractive reverse vaccinology approach, we previously identified 14 putative antigenic proteins unique to NE-causing strains of C. perfringens. In the current work, the in silico findings were confirmed by PCR and sequencing, and five vaccine candidate proteins were produced and purified subsequently. Among them, two candidates were hypothetical proteins, two candidates were prepilin proteins which are predicted to form the subunits of a pilus structure, and one candidate was a non-heme iron protein. Western blotting and ELISA results showed that immunization of broiler chickens with five of these proteins raised antibodies which can specifically recognize both the recombinant and native forms of the protein in pathogenic C. perfringens.

Effects of Supplementation with different levels of a multi strain probiotic on the performance of laying chicken

Use of antibiotic growth promoters in poultry production to enhance performance is not recommended due to accumulation of antibiotic residues in the end products which can confer antimicrobial resistance (AMR) to consumers. Inclusion of probiotics in layers diets has reportedly enhanced laying performance and egg quality without the risks of AMR. A study to determine the effect of supplementation of a multi-strain probiotic on performance and egg quality was carried. A multi-strain probiotic (MolaPlus®) was purchased from a reputable supplier and administered to laying birds via drinking water at different levels; Prob0(control), Prob2.5(2.5ml/L), Prob5(5ml/L), Prob10(10ml/L) and Prob15(15ml/L). The birds were fed on mash feed which was purchased from a reputable feed manufacturer. One hundred and fifty (150) 65-weeks old ISA Brown were recruited from a laying flock and assigned to the five (5) treatments. The feed intake, body weight, egg weight, egg specific gravity, yolk colour, eggshell weight, and thickness was recorded weekly for 5 weeks. Hen day egg production and water intake were recorded daily while the mineral content of the eggshells (Ca &amp; P) was determined during the 1st, 3rd and 5th week. The mean daily feed intake, feed conversion ratio (FCR), body weight, hen day egg production, water intake, yolk colour, egg weight, specific gravity, shell weight, shell thickness and eggshell % were not influenced significantly (p &gt; 0.05) by probiotic inclusion levels. There was a significant (p &lt; 0.05) increase in calcium content of the shells with inclusion of probiotics with Prob5 (52.8%) being the highest. The phosphorus content of the eggshells was significantly higher (p &lt; 0.05) for Prob5 (0.5311) and Prob15 (0.5093) compared to control (Prob0), Prob2.5 and Prob10. From the findings, it can be concluded that a multi-strain probiotic (MolaPlus®) can be included in layers diet via drinking water to improve egg quality

In vitro interaction between essential oil compounds and halquinol against zoonotic pathogenic bacteria

The use of growth-promoting antibiotics has led to an increase in antimicrobial resistance; therefore, the search for new alternatives is essential. As many producers are afraid of applying new technologies, the association between conventional and new methods is an opportunity to introduce innovative approaches. The objective of this research was to evaluate the interaction between halquinol and allyl isothiocyanate (AITC), cinnamaldehyde (CIN), and carvacrol (CA). The minimum inhibitory concentrations were evaluated against Salmonella and Escherichia coli, in addition to their fractional inhibitory concentration index (FICindex), the potential for antimicrobial resistance, and the reversal of halquinol resistance. The compounds were effective when used isolated, with an emphasis on AITC, effective in concentrations between 31.25 and 500 μL/L. Halquinol was effective in the range from 18.75 to 600 μg/mL, working within the range recommended by the manufacturer (30–60 ppm) for most bacteria. The FICindex has shown that the combinations of halquinol with CIN and CA presented mostly synergistic and additive effects. In sublethal exposures, prolonged exposure to EOC mainly led to the potentiation of their effects, and exposure to halquinol led to resistance, increasing its inhibitory concentration by approximately 10 times. Resistance reversal tests showed that AITC and CIN have the potential to minimize resistance to halquinol in vitro.

Influence of fermented feeds on the microbiome of the gastrointestinal tract and efficiency in animal nutrition

The gut microbiome of animals varies by species, age, sex, and nutrition. The content of nutrients in the diet as well as feed additives (synbiotics, eubiotics, phytobiotics) determine the quantity and quality of the intestinal flora. The ban on the use of antibiotic growth promoters (AGP) has led to the search for various effective alternatives that affect the gut microbiome, animal health and production results. It has been shown that the use of fermented feeds, beneficially modifying the composition of the intestinal flora, can be a significant alternative to AGP in the production and breeding of monogastric animals. The use of fermented feeds in wet nutrition or in dry mixtures contributes to the improvement of the nutritional value of the diet by increasing the content of protein and exogenous amino acids and polyunsaturated fatty acids, reducing the content of anti-nutritional substances (glucosinolates, phytates, β-glycinates) in feeds (rapeseed, soybean, lupins, horse bean) and increasing the concentration of beneficial microorganisms (Bacillus and Lactobacillus) and their products (bacteriocins, organic acids).

Antioxidant and Antimicrobial Properties of Selected Phytogenics for Sustainable Poultry Production

The use of antibiotic growth promoters (AGP) in poultry production not only promotes the emergence of pathogenic multi-drug resistant bacteria, but it also compromises product quality, threatens animal and human health, and pollutes the environment. However, the complete withdrawal of AGP without alternatives could result in uncontrollable disease outbreaks that would jeopardize large-scale poultry intensification. Thus, the use of phytogenic products as potential alternatives to in-feed AGP has attracted worldwide research interest. These phytogenic products contain numerous biologically active substances with antioxidant and antimicrobial activities that can enhance poultry health, growth performance, and meat quality characteristics. In addition, the incorporation of phytogenic products as feed additives in poultry diets could result in the production of high-quality, drug-free, and organic poultry products that are safe for human consumption. Thus, this review examines the current evidence on the antioxidant and antimicrobial properties of a selection of phytogenic products, their effects on nutrient utilization, and physiological and meat quality parameters in poultry. The paper also reviews the factors that could limit the utilization of phytogenic products in poultry nutrition and proposes solutions that can deliver efficient and sustainable poultry production systems for global food and nutrition security.

Biosafety assessment of lactic acid probiotic isolates obtained from the gastrointestinal tract of livestock, poultry and bees native to Iran

Probiotics are suitable substitutes to reduce the use of growth-promoting antibiotics and antibiotics used to treat livestock infections due to new international laws and consumers' expectations of livestock products. Although lactic acid bacteria, especially Lactobacillus, are safe strains (GRAS11Generally Recognized As Safe), a safety study of new probiotic strains is needed to evaluate their safety and pathogenicity parameters. Such investigations can reduce concerns about antibiotic resistance genes transfer and observe rare cases of infection caused by probiotic usage. In the previous project of Iran Animal Biotechnology Research Institute, several lactic acid species were isolated and identified from the gastrointestinal tract of different farm animals via phenotypic characteristics and 16S rRNA sequencing. These bacteria had probiotic properties and were assessed for acid resistance, antibiotic resistance, bile salts, and antimicrobial activity. In this study, the presence or absence of several genes, such as pathogenic genes, amine-producing genes, and genes associated with antibiotic resistance, were examined by PCR.22Polymerase chain reaction Furthermore, genes that lead to the emergence of antibiotic resistance through other mechanisms such as efflux pumps were also studied in the same way. These studies have led to the achievement of safe strains for the introduction to the large market of livestock, poultry, and aquatic probiotics.

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.

Screening of Bacteria Inhibiting Clostridium perfringens and Assessment of Their Beneficial Effects In Vitro and In Vivo with Whole Genome Sequencing Analysis.

Various countries and organizations call for banning the use of antibiotic growth promoters (AGPs) as prophylaxis and for growth promotion in the livestock industry. Hence, seeking a substitute for antibiotics is strongly required by the livestock industry to maintain the productivity level and profits. Probiotics could represent one viable solution because of their beneficial effects on host health and maintaining the intestinal microbiota balance. In the present study, we aimed to isolate bacterial strains with probiotics properties from JinHua pig (a Chinese native pig breed) gastrointestinal tract that have antagonistic activity against to common disease-causing bacteria on farms. The four most potent strains were isolated (PP31, BA11, BA40, BV5) by the agar well diffusion method and further characterized by acid, bile salt, trypsin tolerance, whole genome sequencing (WGS), and suppressing Clostridium perfringens adhesion to IPEC-J2 cells. According to these results, BA40 had the highest number and variety of probiotic secondary metabolic secretion genes and capacity to exclude the attachment of Clostridium perfringens to IPEC-J2 cells as same as PB6. The animal experiment in vivo illustrated that BA40 and PB6 could reduce the phenomenon induced by Clostridium perfringens challenge of body weight loss, colon length decrease, pro-inflammatory cytokine increase, and Clostridium perfringens and Escherichia coli increase. The present study provides evidence that BA40 could represent a novel probiotic candidate as PB6, which exhibited some probiotic features and mitigated the burden of Clostridium perfringens associated gut disease.

Los productos bióticos, definición y modo de acción

The gut microbiota has been referred to as the hidden metabolic “organ” due to its enormous impact on host metabolism, physiology, nutrition, and immune system. The relationship between the gut microbiota and the animal host is complex, changing, and generally mutually beneficial. As this relationship is complex, strategies have been studied to help modulate the microbiota to result in greater health and performance. Feed supplementation with biotic products is one of these strategies. These supplements have indirect effects via the manipulation of the quality of the microbiota and an improvement in the intestinal epithelial barrier. In addition to these functions, a stimulation of the host's immune system, a decrease in the colonization of pathogens and relief from stress have also been reported. Therefore, these supplements are presented as a safe alternative to the use of antibiotic growth promoters. The objective of this review is to know what biotic products are and how they work, as well as their application in animal production.

Evaluation of Non-Fermented and Fermented Chinese Chive Juice as an Alternative to Antibiotic Growth Promoters of Broilers.

Simple SummaryRampant use of growth-promoting antibiotics in the poultry industry has resulted in enhanced harmful concentrations in livestock products ushering in the evolution of multidrug resistance strains. Plant feed additives are being explored, and among them, Chinese chives (CC), which contain various phytonutrients, can offer a promising alternative. We performed a comparative study to examine the effects of non-fermented and fermented CC feed additives on broiler productivity, chicken meat quality, blood composition, intestinal properties, and gut microbiota. We observed a high broiler productivity for the treatment group subjected to fermented CC juice on par with growth-promoting antibiotics. Fermented CC juice influenced low cholesterol content in the broilers while inhibiting the growth of intestinal pathogens.The present study explores the application of CC juice as a suitable feed additive and alternative to conventional antibiotics. We performed a comparative study to investigate the effects of non-fermented and fermented CC juice on broiler productivity, meat quality, blood characteristics, intestinal characteristics, and microbiota associated with intestinal characteristics. A total of 800 one-day-old Ross 308 broiler chickens were randomly assigned to one of the four dietary treatment groups: (1) basal diet (negative control; NC); (2) basal diet + 0.01% enramycin (positive control; PC); (3) basal diet + 3% non-fermented CC juice (NCC; CC juice 10%, water 90%); and (4) basal diet + 3% fermented CC juice (FCC; CC juice 10%, water 90%, Lactobacillus plantarum SK4719). Feed and water were provided ad libitum. Intriguingly, all treatments showed similar results in terms of broiler productivity and chicken meat quality. Considering organ characteristics, the FCC group showed a low spleen weight and lower (p < 0.05) blood levels of AST and total cholesterol (TCHO). Regarding intestinal characteristics, the CC feed additive (NCC and FCC) resulted in a heavier intestinal weight (p < 0.05) without affecting the length ratio of the villi or the crypt compared to the control (NC or PC). NCC and FCC lowered the growth of intestinal pathogens (p < 0.01). In summary, the addition of FCC can maintain poultry health by improving blood compositions and inhibiting the growth of intestinal pathogens, leading to a productivity comparable to that of poultry treated with growth-promoting antibiotics.

Strain-specific quantification of probiotic Bacillus subtilis in feed by imaging high-performance thin-layer chromatography

The European Union has banned the use of antibiotic growth promoters in animal production, which has led to increased use of probiotic microorganisms. These feed additives result in higher costs for farmers, which is why the demand for a quality control system to quantify probiotics in feeds has increased in recent years. Imaging high-performance thin-layer chromatography (HPTLC) was proven to be a robust method for determining the probiotic Bacillus subtilis DSM 29784 strain based on the production of selective bacterial metabolites and thus characteristic metabolite pattern. However, to quantify the specific probiotic strain in the feed, identification of a strain-specific metabolite not produced by genetically very similar bacteria is necessary. Compared to five bacteria with high genetic similarity, a strain-specific metabolite was formed in the probiotic bacteria by a two-step cultivation procedure. Among others, antimicrobial properties were found for this metabolite, which indicated probiotic activity. The hyphenation of normal-phase HPTLC with reversed-phase high-performance liquid chromatography diode array detection and high-resolution mass spectrometry allowed the preliminary assignment of this strain-specific metabolite to the molecular formula C35H44N6O2 (580.3527 Da). This metabolite, produced each time via an upstream cultivation process to generate the standard levels, was used for the quantification of probiotic active cells in the feed. Data on selectivity, linearity, detection limit, recovery, and precision have shown the good performance of the method.