Animal Feed Additives Research Articles

Glucose Metabolism-Modifying Natural Materials for Potential Feed Additive Development.

Glucose, a primary energy source derived from animals' feed ration, is crucial for their growth, production performance, and health. However, challenges such as metabolic stress, oxidative stress, inflammation, and gut microbiota disruption during animal production practices can potentially impair animal glucose metabolism pathways. Phytochemicals, probiotics, prebiotics, and trace minerals are known to change the molecular pathway of insulin-dependent glucose metabolism and improve glucose uptake in rodent and cell models. These compounds, commonly used as animal feed additives, have been well studied for their ability to promote various aspects of growth and health. However, their specific effects on glucose uptake modulation have not been thoroughly explored. This article focuses on glucose metabolism is on discovering alternative non-pharmacological treatments for diabetes in humans, which could have significant implications for developing feed additives that enhance animal performance by promoting insulin-dependent glucose metabolism. This article also aims to provide information about natural materials that impact glucose uptake and to explore their potential use as non-antibiotic feed additives to promote animal health and production. Further exploration of this topic and the materials involved could provide a basis for new product development and innovation in animal nutrition.

Potential Risk of Caffeoylquinic Acids, the Main Polyphenol Components in Coffee, on the Health of Piglets.

As the main coffee polyphenols, caffeoylquinic acids (CQAs) are abundant in coffee-derived products and have the potential to act as novel feed additives for animals. However, research on the side effects of dietary CQAs supplementation is scarce, especially in young animals. Here, we explore the safety of CQAs derived from green coffee beans. Results showed that ingesting 50, 125, 250, and 500 mg/kg of dietary CQAs for 55 days is associated with greater final body weight, average daily gain, and feed efficiency in piglets compared with the control group (P < 0.05). CQAs also increased the apparent digestibility of dry matter, crude protein, and gross energy at a dose over 50 mg/kg (P < 0.05). Interestingly, CQAs supplementation with 500 mg/kg increased the white blood cell count (P < 0.05). Moreover, CQAs supplementation at a dose over 50 mg/kg decreased the serum total cholesterol concentration but increased the immunoglobulin M level in serum (P < 0.05). Importantly, CQAs supplementation had no side effects on organ histopathology and organ weight (P > 0.05). These results suggest that CQAs could serve as a secure and effective additive to improve growth performance without negatively affecting the organs of piglets.

Safety Assessment on the Safety and Efficacy of Pediococcus ⁠pentosaceus DSM 32292 as a Feed Additive for All Animal Species (RP552)

An application was submitted to the Food Standards Agency in March 2021 from Microferm Limited (‘the applicant’) for the new authorisation of an additive (Pediococcus pentosaceus DSM 32292), under the category of ‘technical additive’ and functional group ‘silage additives’. The additive is proposed to be used in all animal species, with a proposed minimum content of 1 x 1010 CFU / g to be applied to silage at a minimum of 5 x 107 CFU / kg. To support the Food Standards Agency (FSA) and Food Standards Scotland (FSS) in evaluating the dossier, the Animal Feed and Feed Additives Joint Expert Group (AFFAJEG) and the Advisory Committee on Animal Feedingstuffs (ACAF) were asked to review the dossier and the supplementary information from the applicant. The FSA/FSS concluded, based on the ACAF’s advice, that the additive was correctly identified and characterised, and that the additive can be considered safe for the target species, consumer, and the environment. The additive was identified as potentially harmful by contact with skin or eyes and a respiratory sensitiser. It was concluded that the additive can be considered efficacious for moderately difficult to ensile forages. No conclusion could be reached on efficacy for difficult to ensile forages. The views of AFFAJEG and ACAF have been taken into account in the safety assessment which represents the opinion of the FSA and FSS.

Continuous Liquid-Liquid Extraction of Medium-Chain Fatty Acids from Fermentation Broth Using Hollow-Fiber Membranes.

Medium-chain fatty acids (MCFAs; carbon-lengths: C6-C12) are high-value platform chemicals that serve a variety of industrial applications, including green antimicrobials, food ingredients, animal feed additives, cosmetics, fragrances, pharmaceuticals, and structured lipids. Currently, most MCFAs are produced from palm and coconut oil originating from Southeast Asia and South America. The conventional approach to harvesting palm and coconut fruits causes considerable ecological damage in these regions. Therefore, researchers are developing biological approaches (e.g., precision and open-culture fermentations) to generate MCFAs more sustainably using low-value substrates (e.g., methanol, ethanol, lactate) or organic wastes as feedstock. Microbial chain-elongation (CE) is a rapidly maturing open-culture fermentation platform that converts short-chain fatty acids (SCFAs; carbon lengths: C1-C5) into a subset of these MCFAs at industrially relevant rates. However, continuous in situ extraction of MCFA products is necessary not only to avoid product inhibition but also to facilitate the recovery of MCFAs in a pure and usable form.Liquid-liquid extraction (LLE) using hollow-fiber membranes and targeted extractant mixtures has proven a robust approach to selectively extract MCFA products from fermentation broths containing SCFAs. Here, the application of LLE for continuous MCFA removal is demonstrated using CE as the reference fermentation system and 3% (w/v) trioctylphosphine oxide in mineral oil as the extractant system. Fatty acids ranging from valeric acid (C5) to caprylic acid (C8) are selectively removed from SCFA-containing broths and concentrated to high titers in a semi-batch alkaline stripping solution for downstream processing.

A dual-channel sensing platform for the cross-interference-free detection of tetracycline and copper ion

Tetracycline (TC) and copper ion (Cu2+), as important additives in animal feed, play a crucial role in disease prevention and growth regulation. However, the abuse leads to concentration accumulation, which seriously threatens human health and the ecological environment. There is an urgent need to develop a detection method to achieve fast and synchronous detection of these pollutants without cross-interference. Here, a carbon dots-doped lanthanide-based fluorescent nanosensor (CDs@Tb-MOFs@SiO2–NH2-Eu) was synthesized, which can detect TC in the 380 nm channel by “antenna effect” and internal filtering effects (IFE), and identify Cu2+ in the 320 nm channel. The sensor was highly sensitive to TC within 0–4 μM with a detection limit as low as 3.64 nM, and Cu2+ could be detected within 0–40 μM with a detection limit of 38 nM. A portable dual-channel visual fluorescence sensor was obtained by loading the probes onto test paper and cotton swabs in food samples, which indicates the practicability of this sensing strategy.

The Potential of Grape Polyphenols Additive in Pig Nutrition: Chemical Structure, Bioavailability and Their Effect on Intestinal Health of Pigs

The recognition of the necessity for employing natural additives in animal feed has grown alongside the ban on antibiotics in the animal feed sector. Grapes, as well as by-products of the wine-making industry (grape marc and seed extracts), possess biologically active chemical constituents that can be used to improve animal production by incorporating them into animal feed. Grapes are a valuable resource of polyphenols, especially flavonoids, stilbenes and phenolic acids, most of them showing therapeutic or health-promoting properties. The purpose of this review is to elucidate the impact of polyphenols on animal gut health. The first section of the review discusses the chemical structure of the major polyphenols in grapes and the polyphenols’ bioavailability and metabolism in pigs. The second and major part of the review reviews the results of investigations into the antioxidant, antimicrobial and prebiotic effects of grape polyphenols in pig diets, as well as their regulation of intestinal barrier functions through signalling pathways and intestinal responses. All of this is supported by previous research, findings and conclusions. There are fewer recorded pig studies, but the inclusion of up to 9% grape by-products resulted in improved performance with an increased mean daily gain. Ultimately, this analysis concluded that supplementation of pigs with grape phenolic compounds as natural feed additives enhanced their antioxidant capacity, improved humoral and cellular immune responses, and promoted gut ecosystem biodiversity and the overall production performance in pigs.

Characterization of a novel multifunctional glycoside hydrolase family in the metagenome-assembled genomes of horse gut

The gut microbiota is a treasure trove of carbohydrate-active enzymes (CAZymes). To explore novel and efficient CAZymes, we analyzed the 4,142 metagenome-assembled genomes (MAGs) of the horse gut microbiota and found the MAG117.bin13 genome (Bacteroides fragilis) contains the highest number of polysaccharide utilisation loci sites (PULs), indicating its high capability for carbohydrate degradation. Bioinformatics analysis indicate that the PULs region of the MAG117.bin13 genome encodes many hypothetical proteins, which are important sources for exploring novel CAZymes. Interestingly, we discovered a hypothetical protein (595 amino acids). This protein exhibits potential CAZymes activity and has a lower similarity to CAZymes, we named it BfLac2275. We purified the protein using prokaryotic expression technology and studied its enzymatic function. The hydrolysis experiment of the polysaccharide substrate showed that the BfLac2275 protein has the ability to degrade α-lactose (156.94 U/mg), maltose (92.59 U/mg), raffinose (86.81 U/mg), and hyaluronic acid (5.71 U/mg). The enzyme activity is optimal at pH 5.0 and 30 ℃, indicating that the hypothetical protein BfLac2275 is a novel and multifunctional CAZymes in the glycoside hydrolases (GHs). These properties indicate that BfLac2275 has broad application prospects in many fields such as plant polysaccharide decomposition, food industry, animal feed additives and enzyme preparations. This study not only serves as a reference for exploring novel CAZymes encoded by gut microbiota but also provides an example for further studying the functional annotation of hypothetical genes in metagenomic assembly genomes.

Impact of biohumus and manure on the economic efficiency of winter wheat in the production of ecologically pure products

The ecological agricultural system excludes or limits the use of synthetic fertilizers, pesticides (herbicides), growth regulators, and animal feed additives. Organic fertilizers are used in ecological agriculture. Biohumus and manure, which are organic fertilizers, were used in our research. Application of fertilizers is considered important depending on the economic benefit obtained from them. The impact of soil cultivation and application of fertilizers under winter wheat on irrigated grass-grey soils on economic efficiency has been studied. It was determined that the yeast value of 1 quintal, the net income from 1 ha area, and the level of profitability in all variants of minimum cultivation were higher than traditional cultivation. Keywords: Ecological agriculture, biohumus, manure, winter wheat, economic efficiency, net income, profitability

Alternative ways of using the mushroom substrate as an additive for feed with the purpose of improving animal productivity in agriculture (review)

In modern agriculture, considerable attention is paid to the search for effective and environmentally safe methods of increasing animal productivity. One of the promising directions is the use of mushroom substrate as feed additives. Residual mushroom substrate is often considered as waste, but its processing and use can help reduce feed costs and increase farm profitability. In addition, the use of mushroom substrate helps to reduce the burden on the environment, promoting a closedproduction cycle. In the article it is considered the alternative ways of using mushroom substrate as a feed additive in order to improve the productivity of animals in agriculture. Mushroom substrate, the residual product after growing mushrooms, contains a rich complex of nutrients, such as proteins, vitamins, minerals and other bioactive components. The use of this substrate as a feed additive can provide economic benefits for farms, reducing the cost of traditional feed and increasing animal productivity. Studies indicate a positive effect of the mushroom substrate on the health of animals, in particular on the improvement of immunity and the general physiological state. In addition to economic benefits, the use of mushroom substrate helps to reduce the amount of waste and improve the environmental sustainability of agriculture, meeting the principles of circular economy and sustainable development. Objective. To analyze alternative ways of using mushroom substrate as animal feed additives. In the article it is reviewed modern research and practical experience of using mushroom substrate, its chemical composition and potential benefits for animal husbandry. Special attention is paid to the effect of mushroom substrate on the health of animals, their productivity and general economic indicators of farms. Revealing the potential of mushroom substrate as a feed additive can be an important step in the development of sustainable agriculture, in particular, in the conditions of growing demand for food and resources for its production. Conclusions. The article emphasizes the needfor further research to optimize the methods of using the mushroom substrate in feed rations of various animal species and to develop new technologies for its processing. The practical implementation of these studies can significantly increase the efficiency and competitiveness of agricultural enterprises. Keywords: mushroom substrate, chemical composition, feed additive, animal productivity, agriculture, bioactive components, feeding.

Antibacterial and gut health effects of Amomum tsao-ko in aquatic feed: A sustainable alternative to chemical antibiotics.

Amomum tsao-ko Crevost et Lemarie (Zingiberaceae), an aromatic plant, has been considered to have diverse medicinal values and economic significance. It has been reported to possess antibacterial, antioxidant, and antidiabetic effects. With the increasing risk of diseases in aquaculture, there is a need for alternative solutions to chemical antibiotics. Plant extracts have shown promise as natural feed additives for aquatic animals. In this study, the antibacterial effect of Amomum tsao-ko crude extracts was evaluated using the Oxford cup method. The extracts exhibited significant antimicrobial activity against Salmonella typhimurium and Salmonella enteritidis. Furthermore, the addition of Amomum tsao-ko to fish feed resulted in notable changes in the gut structure of zebrafish and tilapia. The length and morphology of intestinal villi were enhanced, promoting improved digestion. Analysis of the gut microbial community revealed that Amomum tsao-ko supplementation induced key changes in the gut microbial community composition of both zebrafish and tilapia. Notably, a 1% inclusion of Amomum tsao-ko resulted in a marked rise in Proteobacteria levels in zebrafish, which diminished at 10% dosage. The supplement elicited mixed reactions among other bacterial phyla like Actinobacteria and Verrucomicrobiota. Fluctuations were also observed at the genus level, pointing to the concentration of Amomum tsao-ko playing a pivotal role in influencing the structure of intestinal bacteria. The findings of this study suggest that Amomum tsao-ko has antibacterial properties and can positively influence the gut health of fish. The potential use of Amomum tsao-ko as a natural feed additive holds promise for improving aquaculture practices and reducing reliance on chemical antibiotics. Further research is needed to explore the full potential and applications of Amomum tsao-ko in fish feed development.

Modern problems of preclinical studying feed additives for animals and ways to solve them

Resource-saving technology in agriculture is the use of stimulating additives in animal feeding rations that promote better absorption of feed. One of the measures to prevent toxicosis in industrial livestock and poultry farming is to determine the toxicity of feed. The variety of existing methods makes it possible to determine the level and class of drug toxicity at the initial stage. In the developed classification for veterinary drugs, the cumulation coefficient, therapeutic breadth index and dose level of toxic effect are used, which makes it possible to predict the nature and degree of their danger at the stage of preclinical study of feed additives. To determine the listed indicators, it is necessary to establish LD50and the cumulation coefficient. Since feed additives are introduced into the body through the digestive tract, during preclinical studies they are studied and classified according to their hepatotoxic effect. Bilirubin, albumin, and enzyme activity contained in the blood (glutamate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and the ratio of alanine aminotransferase to alkaline phosphatase) are used as markers. It is necessary to determine the de Ritis, Schmidt coefficient and the R index. This will minimize the intake of toxic feed additives into the animals’ bodies and will contribute to an increase in their productivity.

Nanoformulations for lysozyme-based additives in animal feed: An alternative to fight antibiotic resistance spread

Abstract The problem of antibiotic resistance (AR) in pathogenic bacteria due to the massive use of antibiotics in animals is an underestimated issue. Finding alternatives to reduce or eliminate the appearance and spread of AR is a pressing issue for humanity. Enzymes with antibiotic properties may serve as antimicrobial agents, less prone to generating AR due to their proteic nature and mode of action. Lysozyme is a natural antimicrobial agent, amenable to replacing small-molecule antibiotics in animal farming (poultry and livestock) due to its similar effects on animal health and growth. Moreover, it is safe for human and animal consumption and environmentally friendly due to its biodegradability. The development and testing against pathogens of lysozyme-containing nanomaterials fabricated with biocompatible polymers, particularly polysaccharides is reviewed, focusing on their antimicrobial properties, often superior to lysozyme alone due to a synergistic effect of the nanoscaled materials.

Development of Zeolite‐Loaded Air‐Brushed Nanofibers for Oral Use and Its Characterization

AbstractZeolites are commercially available and naturally occurring minerals and synthetic materials, they are crystalline aluminosilicates with distinctive chemical and structural properties. Zeolites have a wide range of uses, including catalysis, gas separation, agronomy, animal feed additives, ecology, medicine, and cosmetics. The antibacterial activity of zeolite‐based nanofibers is fabricated and investigated in the current work utilizing a novel airbrushing method. Airbrushing is used to create zeolite‐loaded nanofibers with two groups of 5% and 10% zeolite, respectively. Scanning electron microscopy (SEM), Attenuation of Reflectance Fourier Transform Infrared Spectroscopy (ATR‐FT‐IR), contact angle measurement and an antibacterial test against Streptococcus mutans are used to characterize the fabricated zeolite‐loaded nanofibers. The SEM pictures demonstrate that the innovative strategy used in the study—air brushing—to effectively produce zeolite‐loaded nanofibers is a success. The morphology and diameter in nanometers is verified by SEM images for both groups. The ATR‐FT‐IR peaks confirm the blended compound and its chemical structure. The water contact angle measurement of the nanofibers of both groups show the hydrophobic qualities based on wettability. The findings of the zeolite nanofiber antibacterial test show a zone of inhibition (ZOI) of 19 mm compared to a positive control groups ZOI of 28 mm, indicating superior antibacterial activity against gram‐positive S. mutans. Based on the findings, it can be stated that zeolite nanofiber can be created by airbrushing and has antibacterial properties that can be utilized to stop dental caries, where S. mutans is the primary pathogenic organism.

Evaluation of some bioactive nutraceutical compounds in agro-industrial waste used as animal feed additives

Evaluation of some bioactive nutraceutical compounds in agro-industrial waste used as animal feed additives

An NADH/NAD+-favored aldo-keto reductase facilitates avilamycin A biosynthesis by primarily catalyzing oxidation of avilamycin C.

Avilamycins, which possess potent inhibitory activity against Gram-positive bacteria, are a group of oligosaccharide antibiotics produced by Streptomyces viridochromogenes. Among these structurally related oligosaccharide antibiotics, avilamycin A serves as the main bioactive component in veterinary drugs and animal feed additives, which differs from avilamycin C only in the redox state of the two-carbon branched-chain of the terminal octose moiety. However, the mechanisms underlying assembly and modification of the oligosaccharide chain to diversify individual avilamycins remain poorly understood. Here, we report that AviZ1, an aldo-keto reductase in the avilamycin pathway, can catalyze the redox conversion between avilamycins A and C. Remarkably, the ratio of these two components produced by AviZ1 depends on the utilization of specific redox cofactors, namely NADH/NAD+ or NADPH/NADP+. These findings are inspired by gene disruption and complementation experiments and are further supported by in vitro enzymatic activity assays, kinetic analyses, and cofactor affinity studies on AviZ1-catalyzed redox reactions. Additionally, the results from sequence analysis, structure prediction, and site-directed mutagenesis of AviZ1 validate it as an NADH/NAD+-favored aldo-keto reductase that primarily oxidizes avilamycin C to form avilamycin A by utilizing abundant NAD+ in vivo. Building upon the biological function and catalytic activity of AviZ1, overexpressing AviZ1 in S. viridochromogenes is thus effective to improve the yield and proportion of avilamycin A in the fermentation profile of avilamycins. This study represents, to our knowledge, the first characterization of biochemical reactions involved in avilamycin biosynthesis and contributes to the construction of high-performance strains with industrial value.IMPORTANCEAvilamycins are a group of oligosaccharide antibiotics produced by Streptomyces viridochromogenes, which can be used as veterinary drugs and animal feed additives. Avilamycin A is the most bioactive component, differing from avilamycin C only in the redox state of the two-carbon branched-chain of the terminal octose moiety. Currently, the biosynthetic pathway of avilamycins is not clear. Here, we report that AviZ1, an aldo-keto reductase in the avilamycin pathway, can catalyze the redox conversion between avilamycins A and C. More importantly, AviZ1 exhibits a unique NADH/NAD+ preference, allowing it to efficiently catalyze the oxidation of avilamycin C to form avilamycin A using abundant NAD+ in cells. Thus, overexpressing AviZ1 in S. viridochromogenes is effective to improve the yield and proportion of avilamycin A in the fermentation profile of avilamycins. This study serves as an enzymological guide for rational strain design, and the resulting high-performance strains have significant industrial value.

Effects of dietary bacterial culture of fengycin-producing Bacillus subtilis on growth performance, intestinal and hepatopancreas health, intestinal microbiota and disease resistance of common carp (Cyprinus carpio)

Probiotics are important for the normal physiological functions of fish and are used as feed additives in many aquatic animals. The purpose of this study is to explore the effects of dietary bacterial culture of fengycin-producing Bacillus subtilis (B. subtilis) on growth performance, intestinal and hepatopancreas health, intestinal microbiota and disease resistance of common carp (Cyprinus carpio). Three diets were formulated with supplementation of bacterial culture of fengycin-producing B. subtilis at 0, 0.3 and 0.5 g/kg levels, and these diets were defined as control, BS0.3 and BS0.5, respectively. After 6-week feeding, the infiltration of inflammatory cells was improved in the BS0.3 and BS0.5 groups. And the anti-inflammatory cytokines (interleukin (IL)-10 and tumor growth factor β (TGF-β) were prominently increased in the hepatopancreas of fish fed with dietary B.subtilis diets (P < 0.05). The activity of lysozyme, the levels of complement component (C) 3 and C4 were remarkably increased in the hepatopancreas and intestine of fish fed with B.subtilis supplemented diets (P < 0.05). Histological (intestinal villi height was increased in BS0.3 and BS0.5 groups) (P < 0.05) and the expression of the gut physical barrier-related genes (Zona occludens-1 (ZO-1) and occludin) were increased in the B.subtilis supplemented groups (P < 0.05). The expression of pro-inflammatory cytokines (IL-1β, IL-6 and tumor necrosis factor α (TNF-α) and anti-inflammatory cytokines (IL-10 and TGF-β) were remarkably up-regulated in the intestine of fish fed with BS0.3 diet (P < 0.05), while the expression of IL-6 was remarkably diminished in the intestine of fish fed with BS0.5 diet (P < 0.05). Besides, the intestinal microbiota analysis illustrated that in the intestine of the fish groups fed with BS0.3 and BS0.5 diets, the abundance of Fusobacteriota and Cetobacterium were prominently increased (P < 0.05). After challenged with Aeromonas veronii Hm091, the survival rate of fish fed with BS0.3 diet was markedly improved (P < 0.05). Based on these results, supplementation of bacterial culture of fengycin-producing B. subtilis at a level of 0.3 g/kg has beneficial effects on immunity, intestinal microbiota, and disease resistance of common carp.

Application of Organic Acid Salts as Feed Additives in Some Aquatic Organisms: Potassium Diformate

Antibiotics are the primary measures employed in the prevention and treatment of diseases in aquaculture. However, the frequent utilization of antibiotics can significantly impact the growth and reproduction of aquatic organisms, resulting in water pollution. The European Union (EU) has prohibited antibiotic additives in animal feed. Potassium diformate (KDF) represents the first non-antibiotic feed additive approved by the EU as a viable alternative to antibiotics. Its application in animal nutrition has been validated, demonstrating beneficial health effects. This article reviews the physicochemical properties, biological functions, synthesis conditions, and applications of KDF in aquaculture and looks toward to its future potential. It also provides insights into improving the utilization of KDF in aquaculture practices.

Staphylococcus aureus mutants resistant to the feed-additive monensin show increased virulence and altered purine metabolism.

Ionophores are antibacterial compounds that affect bacterial growth by changing intracellular concentrations of the essential cations, sodium and potassium. They are extensively used in animal husbandry to increase productivity and reduce infectious diseases, but our understanding of the potential for and effects of resistance development to ionophores is poorly known. Thus, given their widespread global usage, it is important to determine the potential negative consequences of ionophore use on human and animal health. In this study, we demonstrate that exposure to the ionophore monensin can select for resistant mutants in the human and animal pathogen Staphylococcus aureus, with a majority of the resistant mutants showing increased growth rates in vitro and/or in mice. Whole-genome sequencing and proteomic analysis of the resistant mutants show that the resistance phenotype is associated with de-repression of de novo purine synthesis, which could be achieved through mutations in different transcriptional regulators including mutations in the gene purR, the repressor of the purine de novo synthesis pathway. This study shows that mutants with reduced susceptibility to the ionophore monensin can be readily selected and highlights an unexplored link between ionophore resistance, purine metabolism, and fitness in pathogenic bacteria.IMPORTANCEThis study demonstrates a novel link between ionophore resistance, purine metabolism, and virulence/fitness in the key human and animal pathogen Staphylococcus aureus. The results show that mutants with reduced susceptibility to the commonly used ionophore monensin can be readily selected and that the reduced susceptibility observed is associated with an increased expression of the de novo purine synthesis pathway. This study increases our understanding of the impact of the use of animal feed additives on both human and veterinary medicine.

In silico analysis of polyphenols modulate bovine PPARγ to increase milk fat synthesis in dairy cattle via the MAPK signaling pathways.

This study investigates the potential phytochemicals that modulate bovine peroxisome proliferator-activated receptor gamma (PPARγ) and the mitogen-activated protein kinase (MAPK) pathways to enhance milk fat production in dairy animals. Bovine PPARγ, a key member of the nuclear hormone receptor superfamily, plays a vital role in regulating metabolic, cellular differentiation, apoptosis, and anti-inflammatory responses in livestock, while the MAPK pathway is contributory in cellular processes that impact milk fat synthesis. This approach involved an all-inclusive molecular docking analysis of 10,000 polyphenols to identify potential PPARγ ligands. From this extensive screening, top 10 compounds were selected that exhibited the highest binding affinities to bovine PPARγ. Particularly, curcumin sulfate, isoflavone, and quercetin emerged as the most promising candidates. These compounds demonstrated superior docking scores (-9.28 kcal/mol, -9.27 kcal/mol, and -7.31 kcal/mol, respectively) and lower RMSD values compared to the synthetic bovine PPARγ agonist, 2,4-thiazolidinedione (-4.12 kcal/mol), indicating a strong potential for modulating the receptor. Molecular dynamics simulations (MDS) further affirmed the stability of these polyphenols-bovine PPARγ complexes, suggesting their effective and sustained interactions. These polyphenols, known as fatty acid synthase inhibitors, are suggested to influence lipid metabolism pathways crucial to milk fat production, possibly through the downregulation of the MAPK pathway. The screened compounds showed favorable pharmacokinetic profiles, including nontoxicity, carcinogenicity, and high gastrointestinal absorption, positioning them as viable candidates for enhancing dairy cattle health and milk production. These findings may open new possibilities for the use of phytochemicals as feed additives in dairy animals, suggesting a novel approach to improve milk fat synthesis through the dual modulation of bovine PPARγ and MAPK pathways.

Effects of different additives on cattle feed intake and performance - a systematic review and meta-analysis.

In the last few years, there has been a growing interest in the use of natural feed additives in animal feed. These can be used as replacements for antibiotics, to alter rumen fermentation and increase feed efficiency in ruminants. Therefore, the objective of this study is to evaluate the effects of adding different feed additives in the diet of beef and dairy cattle on their performance, dry matter intake (DMI) and feed efficiency, through a systematic review followed by meta-analysis. The systematic review suggested 43 peer-reviewed publications, according to the pre-established criteria. In beef cattle, the ionophore antibiotics reduced the DMI, improved the feed efficiency without interfering in the average daily gain (ADG). Non-ionophore antibiotics and propolis extract increased the ADG. In dairy cattle, the ionophores, yeast-based additives, and enzyme additives increased the feed efficiency, DMI, and daily milk production (MY), respectively. Essential oil supplementation in beef and dairy cattle had no effect on the feed intake and animal performance. The systematic review and meta-analysis allowed us to conclude that different feed additives have different effects on cattle performance, however, our results suggest that there are a few gaps regarding their effects on animal performance.