Search Results (104)

Aquaculture currently supplies over half of the world’s fish and relies heavily on feed additives to enhance growth, improve feed efficiency, and increase disease resistance. This review consolidates peer-reviewed studies identified through targeted searches of Web of Science, Scopus, and Google Scholar, focusing on aquaculture feed additives. It emphasizes the principal classes of additives employed in finfish and shrimp cultivation, such as natural immunostimulants (including beta-glucans and nucleotides), probiotics, prebiotics, synbiotics, phytogenics, enzymes, and synthetic nutrients. For each, it summarizes their mechanisms of action, commonly reported inclusion rates, production outcomes, environmental risks, and regulatory statuses. Evidence indicates that immunostimulants enhance innate defences (including phagocyte activity and cytokine responses). Probiotics and prebiotics, on the other hand, regulate gut microbiota and barrier function. Phytogenics offer antimicrobial and antioxidant effects, and synthetic additives provide targeted nutrients or functional compounds that support growth and product quality. Where data are available, typical application ranges include probiotics in the order of 10⁴–10⁹ CFU per gram, prebiotics at approximately 2–10 g per kilogram, and pigments or antioxidants (such as astaxanthin) at 50–100 mg per kilogram. Significant gaps exist, notably the absence of species-specific dose–response data for tropical and subtropical aquaculture species, as well as limited experimental evidence regarding additive–additive interactions under commercial rearing conditions. Additional gaps include long-term ecological fate, regional regulatory discrepancies, and species-specific dose–response relationships. It is recommended that mechanistic studies employing omics approaches, standardised dose–response trials, and harmonized risk assessments be conducted to promote the sustainable and evidence-based application of feed additives. Full article

This study evaluated the effects of lasalocid sodium (LASA) and essential oils on the fermentation and nutritional quality of total mixed ration (TMR) silages. A 4 × 2 factorial design tested four additives—a control (distilled water), LASA (375 mg/kg DM), limonene essential oil (LEO), and a blend of cinnamaldehyde and carvacrol (EOB), both at 400 mg/kg DM—during summer and autumn. The TMRs were formulated to meet the nutritional requirements of lactating cows producing 20 kg of milk per day. After 110 days of ensiling, silages were analyzed for fermentation losses, pH, short-chain fatty acids, ammoniacal nitrogen (NH₃-N), aerobic stability (AS), and chemical composition. The additives significantly improved dry matter recovery (DMR), especially LASA and EOB in autumn. EOB showed the lowest effluent losses and highest AS, with higher acetic acid and lower NH₃-N contents. LEO and EOB increased lactic acid, while LASA reduced ethanol and butyric acid levels in summer. Crude protein increased with LEO in autumn, and LASA and LEO improved total digestible nutrients (TDNs) in summer. EOB-treated silages had higher fiber fractions in autumn, without compromising feed value. Therefore, LASA, LEO, and particularly EOB enhanced silage fermentation and nutrient preservation, with EOB showing the most consistent results across seasons. Full article

Given the restrictions on animal growth promoters, alternative plant-based additives—particularly those rich in phenolic compounds, such as agro-industrial by-products—have been explored. These additives help to mitigate heat stress, which negatively affects productivity by impacting intestinal health and antioxidant status. This study evaluated the effects of individual and combined supplementation of ferulic acid (FA) and grape pomace (GP) on antioxidant enzyme activity, as well as intestinal histomorphometry, in finishing pigs under heat stress. Forty Yorkshire × Duroc pigs were randomly assigned to four treatments: control, 25 mg/kg FA, 2.5% GP, and MIX (FA + GP). FA supplementation increased intestinal villus height, while GP increased villus width in the duodenum and jejunum (p < 0.05). Antioxidant enzyme activity (SOD, CAT, and GPx) increased in pigs supplemented with GP (p < 0.05). These results suggest that GP and FA have potential as functional additives in monogastric diets, improving intestinal health and muscle antioxidant status and contributing to growth modulation. Full article

This study aimed to investigate the effects of dietary supplementation with different levels of ursolic acid (UA) on the growth performance, immune function, intestinal antioxidant capacity, and anti-inflammatory responses of weaned rabbits. A total of 160 Hyla meat rabbits aged 35 days were randomly assigned to four groups. Each treatment group consisted of 8 replicates, with 5 rabbits per replicate. The rabbits were fed a basal diet (control group, CON) or experimental diets supplemented with 50, 100, or 200 mg/kg UA for 28 days. Dietary supplementation with 50 mg/kg UA significantly increased (p < 0.05) the average daily gain and average daily feed intake. The villus height, crypt depth, and villus height to crypt depth ratio exhibited quadratic responses (p < 0.05) to increasing dietary UA levels, with rabbits fed 50 mg/kg UA showing optimal ileal morphology. Compared with the CON group, dietary supplementation with 50 mg/kg UA significantly enhanced (p < 0.05) cecal catalase activity, secretory immunoglobulin A, and interleukin-10 (IL-10) levels, while the addition of 200 mg/kg UA increased (p < 0.05) serum catalase activity. The concentrations of serum tumor necrosis factor-α (TNF-α) and cecal IL-10 responded quadratically (p < 0.01 and p = 0.01, respectively) as the dietary UA level increased. With increasing UA supplementation, cecal Kelch-like ECH-associated protein 1 and IL-10 mRNA expression showed linear upregulation (p < 0.05), whereas nuclear factor erythroid 2-related factor 2 (Nrf2), superoxide dismutase 1 (SOD1), quinone oxidoreductase 1 (NQO1), TNF-α, interleukin-6, and interleukin-8 displayed quadratic responses (p < 0.05). Dietary UA at 50 mg/kg significantly downregulated cecal TNF-α and interleukin-1β mRNA expression while upregulating Nrf2, NQO1, and SOD1 mRNA levels (p < 0.05). In conclusion, dietary supplementation with 50 mg/kg UA significantly improved the growth performance of weaned rabbits by improving intestinal morphology, immune function, and antioxidant and anti-inflammatory capacities, demonstrating its efficacy as a natural phytogenic feed additive. Full article

This study evaluated the effects of different doses of limonene essential oil (LEO) and a blend of cinnamaldehyde and carvacrol (BCC) on the fermentative quality and chemical–bromatological composition of total mixed ration (TMR) silages. Two independent trials were conducted, each focused on one additive, using a completely randomized design with four treatments (0, 200, 400, and 600 mg/kg of dry matter), replicated across two seasons (summer and autumn), with five replicates per treatment per season. The silages were assessed for their chemical composition, fermentation profile, aerobic stability (AS), and storage losses. In the LEO trial, the dry matter (DM) content increased significantly by 0.047% for each mg/kg added. Dry matter recovery (DMR) peaked at 97.9% at 473 mg/kg (p < 0.01), while lactic acid (LA) production reached 5.87% DM at 456 mg/kg. Ethanol concentrations decreased to 0.13% DM at 392 mg/kg (p = 0.04). The highest AS value (114 h) was observed at 203.7 mg/kg, but AS declined slightly at the highest LEO dose (600 mg/kg). No significant effects were observed for the pH, neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), or non-fiber carbohydrates (NFCs). In the BCC trial, DMR reached 98.2% at 548 mg/kg (p < 0.001), and effluent losses decreased by approximately 20 kg/ton DM. LA production peaked at 6.41% DM at 412 mg/kg (p < 0.001), and AS reached 131 h at 359 mg/kg. BCC increased NDF (from 23.27% to 27.73%) and ADF (from 35.13% to 41.20%) linearly, while NFCs and the total digestible nutrients (TDN) decreased by 0.0007% and 0.039% per mg of BCC, respectively. In conclusion, both additives improved the fermentation efficiency by increasing LA and reducing losses. LEO was more effective for DM retention and ethanol reduction, while BCC improved DMR and AS, with distinct effects on fiber and energy fractions. Full article

Finding effective alternatives to antibiotics and zinc oxide in livestock feed remains challenging, but phytogenic compounds show promising potential. In the first part of the present study, the in vitro antimicrobial activities of carvacrol, eugenol, garlic oil, star anise oil, and tea tree oil as well as their effects on the biofilm formation of two Escherichia coli field isolates, quorum sensing of Chromobacterium violaceum, and the adhesion of an E. coli field isolate to piglets’ small intestinal mucus were determined. Based on these results, two prototypes were formulated. Phytogenic feed additive (PFA) Core 2, containing carvacrol, eugenol, and star anise oil, showed stronger in vitro antimicrobial activity, inhibition of biofilm formation, and quorum sensing than PFA Core 1, which was mainly composed of garlic oil and tea tree oil. In the second part of the present study, 1000 post-weaning piglets were divided into four groups receiving a control or diets with either PFA Core 1, PFA Core 2, or zinc oxide. Only PFA Core 2 and zinc oxide significantly improved body weight, daily gain, feed efficiency, and fecal scores compared with the control, while PFA Core 1 increased the feed efficiency and fecal scores. The results show that feed additives based on carvacrol and eugenol can improve the growth performance of post-weaning piglets and reduce the incidence of diarrhea, possibly by influencing detrimental bacteria. Furthermore, the present study demonstrates the potential of combinations of in vitro assays to support the development of effective feed additives. Full article

This study aimed to evaluate whether the addition of a phytobiotic additive formulated based on cinnamon and oregano essential oils (50% free and 50% microencapsulated) combined with turmeric extract and tannins to the diet of cows has beneficial effects on health, productivity, and milk quality. In a completely randomized design, eighteen Jersey cows were used in a compost barn system over 45 days. The cows were divided into two homogeneous groups: one control (without additive; n = 9) and another treatment (with a phytobiotic at a dose of 2 g/cow/day; n = 9). The diet was formulated based on corn silage, hay and concentrate for daily 30 L/cow production. Blood and milk samples were collected at 15-day intervals. There was a treatment × day interaction: cows that consumed the phytobiotic additive produced a more significant amount of milk at days 14, 17, 18, 30, 39 and 45 (p ≤ 0.05). When we corrected milk production for fat percentage, we observed higher milk production in the cows that consumed phytobiotics compared to the control during the experimental period (p = 0.01). The feed intake of cows fed phytobiotics was lower (p = 0.01). Thus, feed efficiency was better in cows that consumed phytogenics. There was a higher percentage of fat in the milk of cows that consumed phytobiotics and a higher amount of polyunsaturated fatty acids compared to the control (p = 0.02). There was an increase in total protein and globulin levels (p = 0.01), which may be associated with the interaction of the antimicrobial, antioxidant, and immunomodulatory properties of the phytobiotic additive. An increase in immunoglobulins (p = 0.01) and a reduction in acute-phase proteins (p ≤ 0.05) were observed in the blood of cows in the phytobiotic group. Lower levels of TNF-α, IL-1β and IL-6 and higher levels of IL-10 in the serum of cows that consumed the phytoactive (p = 0.01) reaffirm the anti-inflammatory effect of the additive. Lower levels of lipid peroxidation (TBARS) and reactive oxygen species (ROS) were observed in the serum of cows in the phytobiotic group. Greater catalase and superoxide dismutase activity was observed in cows that consumed the phytogenic (p < 0.01). Therefore, it can be concluded that the additive in question has antioxidant, immunological, and anti-inflammatory actions and has the potential to improve productive performance when corrected for milk fat. Full article

An in vitro and an in vivo study were conducted to investigate the effects of a blend of cinnamaldehyde, eugenol, and capsicum oleoresin (CEC) on rumen fermentation parameters, animal performance, and methane (CH₄) emissions in dairy cows. Continuous culture fermenters (CCF) were utilized to test one of two treatments: (1) CON; no supplementation and (2) CEC supplemented at 0.0125 g/d. The basal diet consisted of grass hay and concentrate (50:50). Supplementation with CEC increased (p < 0.01) total volatile fatty acids (VFA; mM) and decreased (p = 0.02) CH₄ concentration compared with CON in vitro. Additionally, protozoa abundance tended (p = 0.07) to decrease in CEC compared with CON. The in vivo experiment utilized forty Holstein-Friesian dairy cows (32% primiparous and 68% multiparous) averaging 163 ± 48 days in milk (DIM) and 38 ± 6.2 kg/d of milk yield (MY). Cows were blocked by parity and randomly assigned to one of two treatments: (1) CON; no supplementation and (2) CEC supplemented at 1.2 g/cow/d. The basal diet consisted of grass hay and concentrate (40:60). Individual CH₄ emissions were recorded using the sniffer technique. Dry matter intake (DMI) and eating rate were increased (p < 0.01; 3.6% and 5.2%, respectively), while feed efficiency decreased (p < 0.05) in CEC compared with CON. Additionally, CEC decreased (p = 0.02) CH₄ yield by 16.4% and tended to reduce daily CH₄ production (p = 0.09) and CH₄ intensity (p = 0.08) by 13.4% and 14.0%, respectively. Supplementing CEC decreased CH₄ concentration in vitro and CH₄ yield in vivo without negatively impacting performance parameters. Full article

The aim of this study was to evaluate the technical and economic impact of using commercial phytogenic feed supplements and dried Greek Oregano leaves as feed additives on dairy sheep farms. Fifteen farms in the Greek region of Thessaly were divided into intervention and control farms, and techno-economic data were collected before and after supplementation through structured interviews and cost analysis. The results showed that the administration of certain phytogenic supplements and oregano to ewes resulted in improved animal health, higher milk yield, and lower production costs, which created a positive trend in the financial results of the farm. Further research is needed to accurately determine the ideal production stage of the animals for the interventions, the amount of supplements administered, and the selection of appropriate plant species, which would lead to better financial management of the farms. Full article

Puerarin, a bioactive isoflavone extracted from Pueraria lobata, possesses well-documented pharmacological properties, including anti-inflammatory, antioxidant, and metabolic regulatory effects, which have been extensively studied in mammalian models and traditional medicine. Recently, its potential as a functional feed additive in aquaculture has garnered increasing attention. This study aimed to evaluate the effects of dietary puerarin supplementation on growth performance, immune response, antioxidant capacity, and disease resistance in largemouth bass, Micropterus salmoides. A total of 120 fish were randomly assigned to 4 dietary groups, receiving a basal diet supplemented with 0 (control), 200, 500, and 1000 mg/kg puerarin for 8 weeks. The results showed that dietary puerarin significantly (p < 0.05) improved weight gain, with the 200 mg/kg and 500 mg/kg groups exhibiting the best performance. Puerarin supplementation enhanced acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LZM) activities, reduced malondialdehyde (MDA) levels, and increased superoxide dismutase (SOD) and catalase (CAT) activities, indicating improved immune function and oxidative stress resistance in groups receiving medium concentrations of puerarin supplementation. The expression of the TNF-α, IL-6, IL-8, and HSP70 genes was significantly downregulated, especially in the 200 mg/kg and 500 mg/kg groups, suggesting anti-inflammatory and anti-stress effects, while Nrf2 expression was upregulated in the 1000 mg/kg group, reinforcing its antioxidative role. Additionally, puerarin-fed fish exhibited significantly lower mortality rates following Aeromonas hydrophila infection, highlighting enhanced disease resistance. In summary, the dose-dependent effect of puerarin on largemouth bass aquaculture has been revealed in this study. Dietary supplementation with moderate doses of puerarin (200 and 500 mg/kg) effectively suppressed inflammation and enhanced immune function, while the highest dose (1000 mg/kg) may mildly activate the immune system. These findings suggest that puerarin is a promising phytogenic feed additive for improving fish health and aquaculture sustainability. Full article

This study systematically evaluates the effects of dietary supplementation with phytogenic feed additive (0.2%, 0.4%, and 0.8%) on white-feathered broilers (n = 88) through a 42-day controlled trial with the weight of approximately 50 g. The experimental design incorporates a triplicate-group-replicated protocol with daily feed intake monitoring, culminating in comprehensive assessments of the growth performance, slaughter traits, meat quality, and cecal microbiome dynamics. The results demonstrated that the 0.8% supplementation significantly enhanced average daily weight gain (p < 0.05), optimized meat characteristics (elevated the redness of meat, reduced pH; p < 0.05), and restructured cecal microbiota by enriching Deinococcus-Thermus, Bacteroidetes, Actinobacteria, and Cyanobacteria (p < 0.05). Based on microbiota-based functional prediction analyses (COG/KEGG/MetaCyc), phytogenic feed additive significantly activated lipid metabolism pathways in broilers. The immunomodulatory correlations between Deinococcus/Thermus/Cyanobacteria and immune indicators suggested their potential immune-enhancing effects mediated through host immune regulation. The findings established the 0.8% phytogenic feed additive as a multifunctional phytogenic additive that synchronously improves zootechnical performance, meat quality, and microbiome homeostasis, offering a scientifically validated strategy for antibiotic-free precision nutrition in sustainable poultry production. Full article

Pequi oil (PO) is a natural feed additive rich in bioactive compounds, which can modulate antioxidant and immunological systems. Thus, the aim of this study was to evaluate the proteomic profile of laying hens supplemented with PO under heat stress conditions. Ninety-six 26-week-old Lohmann White hens were housed in a completely randomized design with a 2 × 2 factorial arrangement, with two climate chambers (cyclic heat stress and thermoneutral) and two diets (control and 0.6% PO). At 38 weeks old, liver samples were collected for protein extraction and digestion, and were submitted to liquid chromatography–tandem mass spectrometry (LC-MS/MS). A total of 996 differentially expressed proteins were identified in the liver proteome of laying hens fed with 0.6% PO under heat stress. These upregulated proteins (0.95 ≤ p ≤ 1.00) are associated with lipid metabolism (apolipoprotein B; vitellogenin-1; ovotransferrin), the antioxidant system (protein disulfide-isomerase A4; superoxide dismutase 1_ soluble; catalase), the immune system (Ig-like domain-containing protein) and chaperones (HSP 90; HSP 70). PO positively modulates a network of heat shock proteins and antioxidant enzymes, and the unique proteins identified can contribute to the discovery of new biomarkers related to heat stress reduction by phytogenic additives. Full article

The objective was to determine whether dairy cows may activate traditional and alternative inflammatory pathways by consuming a combination of a phytogenic diet (essential oil and pepper resin). Twenty pregnant Jersey cows in the final (third) lactation phase (260 days in milk) were divided into two groups: control, with no additive consumption, and test, with the addition of the phytogenic to the concentrate portion of the diet (150 mg/day/kg dry matter). Blood samples were collected on experimental days 1, 7, 14, 21, 28, 35, and 42 by coccygeal vein puncture to assess the complete blood count, serum biochemistry of levels of total protein, albumin, and globulin, as well as carbohydrate metabolism (glucose), lipid metabolism (cholesterol and triglycerides), protein metabolism (urea), activities of hepatic enzymes (gamma-glutamyl transferase (GGT) and aspartate aminotransferase (AST)), cytokine levels (interleukins IL-1β, IL-6, and IL-10), antioxidant response [thiobarbituric acid reactive substances (TBARS), reactive oxygen species (ROS), total thiol (PSH), and non-protein thiol (NPSH), and glutathione S(GST)], cholinergic system [total cholinesterase (ChE) and acetylcholinesterase (AChE)], purinergic signaling [NTPDase, 5′ectonucleotidase and adenosine deaminase (ADA)], and energetic metabolism enzymes [creatine kinase (CK), pyruvate kinase (PK), and adenylate kinase (AK)]. Productive performance was assessed through feed intake and milk production. The results revealed that the use of phytogenic compounds significantly influenced the cholinergic system and purinergic signaling associated with immunology. The reduction in cholinesterase (ChE) activity and the increase in acetylcholinesterase (AChE) activity in lymphocytes suggest the modulation of the cholinergic system, enhancing the immune response. Furthermore, the elevated activity of adenosine deaminase (ADA) in lymphocytes and platelets, together with increased ATP and ADP hydrolysis in platelets, indicates the beneficial regulation of purinergic signaling, potentially contributing to inflammatory modulation. These effects were accompanied by a lower production of pro-inflammatory cytokines (IL-1β and IL-6) and a higher production of IL-10, reinforcing an anti-inflammatory profile. The reduced leukocyte and lymphocyte counts may reflect a lower inflammatory demand, while the increased levels of NPSH and GST antioxidants suggest cellular protection. Despite these physiological changes, productive performance and milk quality remained unaffected. In summary and practical terms, including this additive in the cows’ diet benefits the cow’s health in the final third of gestation when the animal already has a reduced immune response due to advanced gestation. Full article

Various innovative fish feeds were tested for the production of koi carp in a recirculating aquaculture system, considering insect meal (Acheta domestica) as the main protein source and phytogenic additives (Curcuma longa—turmeric and Beta vulgaris—beetroot) as antioxidants, in the spirit of sustainable aquaculture practice. The growth performance, metabolic rate (respirometry), hematological profile, blood biochemical indicators, and oxidative stress of koi carp were determined, using feeds according to the following experimental design: CF—commercial feed, IF—innovative feed based on cricket meal, BIF—innovative feed (IF) with beetroot, and TIF—innovative feed (IF) with turmeric. The TIF recorded the best growth rate. The lowest values of lipid peroxidation (MDA), standard metabolic rate (SMR), and routine metabolic rate (RMR) were registered for the IF and TIF variants. A reduction in MDA was noted, correlated to the decrease in the metabolic rate regarding SMR and RMR for the IF and TIF. An intensification in amylase was recorded in the TIF and BIF. Compared with the CF, it seems that the IF, TIF, and BIF had a beneficial effect on the koi carp by reducing cholesterol, HDL cholesterol, alanine aminotransferase, triglycerides, and urea and by increasing the concentration of calcium and growth hormone in the blood plasma. Full article

Menthol, the primary active compound in the widely cultivated peppermint plant (Mentha piperita), is well known for its use in human products such as topical analgesics and cold remedies. Menthol’s cooling sensation and ability to locally modulate pain through interactions with transient receptor potential channels make it a valuable bioactive compound. In recent years, menthol’s antimicrobial, anti-inflammatory, and antioxidative properties have drawn attention in the livestock industry as a natural alternative to synthetic antibiotics in feed additives. This review comprehensively examines the existing literature to assess menthol’s effects on animal growth performance, product quality, immune function, gastrointestinal microbial ecosystems, and metabolism across various livestock species. Notably, menthol shows potential for improving feed efficiency, mitigating chronic inflammation and oxidative stress, inhibiting environmental and gastrointestinal pathogens, and enhancing calcium absorption. However, optimal dosages, treatment durations, synergies with other phytogenic compounds, and regulatory mechanisms require further investigation. Additionally, with increasing global temperatures and growing concerns about animal welfare, menthol’s cooling, methane-reducing, and analgesic properties present promising opportunities for advancing sustainable livestock practices. Full article