Untargeted UHPLC-MS metabolic profiling as a valuable tool for the evaluation of eggs quality parameters after dietary supplementation with oregano, thyme, sideritis tea and chamomile on brown laying hens.

INTRODUCTION: Bioactive constituents of medicinal-aromatic plants used as feed additives may affect the metabolic profile and oxidative stability of hen eggs. OBJECTIVES: To determine the effects of dietary supplementation with a mixture of dried oregano, thyme, sideritis tea and chamomile on laying hen performance, egg quality parameters, and oxidative stability in the egg yolk were monitored. METHODS: In this trial 432 hens were allocated in two treatments (unsupplemented vs. supplemented with the mixture) and fed for 42 days. Eggs were collected at the end of the trial period, egg yolk was separated, extracted, and the total phenolic content (TPC) and oxidative stability was measured. Furthermore, LC-MS metabolic profile of eggs was studied and pathway analysis was elaborated in MetaboAnalyst to facilitate annotation of features. RESULTS: Overall, egg production and feed conversion ratio were not affected by the supplementation. However, eggs from the supplemented treatment showed improved shell thickness and strength, and yolk resistance to oxidation. Moreover, LC-MS metabolomic analysis of egg yolk of supplemented and unsupplemented layers showed significant variations and tight clustering in unsupervised principal component analysis due to different chemical profiling of egg yolk. LC-MS study showed that secondary metabolites of aromatic plants did not transfer into yolk, nevertheless the feed supplementation impacted the pathway metabolism of tyrosine, phenylalanine, propanate, and the biosynthesis of aminoacyl-tRNA, phenylalanine, tyrosine and tryptophan. CONCLUSIONS: The dietary supplementation of layers with a mixture of dried medicinal aromatic plants affected shell thickness and strength, the lipid and protein oxidative stability and increased tyrosine and phenylalanine content in eggs.

Larval performance of Zophobas morio (F.) (Coleoptera: Tenebrionidae) on various diets enriched with post-distillation residues and essential oils of aromatic and medicinal plants.

The increasing demands for resources driven by the global population necessitate exploring sustainable alternatives for affordable animal protein over the use of traditional protein sources. Insects, with their high protein content, offer a promising solution, especially when reared on agricultural post-distillation residues for enhanced sustainability and cost-effectiveness. We assessed the development of Zophobas morio (F.) (Coleoptera: Tenebrionidae) larvae on diets enriched with essential oils and post-distillation residues from Greek aromatic and medicinal plants. Two aromatic plant mixtures (A and B) were examined. Mixture A consisted of post-distillation residues, while Mixture B incorporated these residues along with essential oils. Insect rearing diets were enriched with different proportions (10, 20, and 30 %) of these mixtures, with wheat bran serving as the control. Enrichment positively influenced larval development without compromising survival. Larval weight remained unchanged with Mixture A, but improved with Mixture B. No adverse effects were detected in the case of the enriched diets, although higher concentrations of Mixture B prolonged development time.

Combined Dietary Supplementation of Tenebrio molitor Larvae and Chitosan in Growing Pigs: A Pilot Study.

Nowadays, the global animal industry faces considerable challenges in securing sufficient feed resources. Responding to consumer demands for reduced use of antibiotics in animal nutrition, better animal welfare status, and reduced impact on the environment, there is an increased urgency to develop innovative functional feeds with a reduced environmental footprint and the ability to improve meat quality and safety. In an effort to explore innovative feed ingredients for growing pig diets, the combined dietary supplementation of Tenebrio molitor larvae and chitosan was investigated. An experimental trial was performed with 48 weaned pigs (34 days of life; mixed sex) that were randomly assigned to four treatment groups (with six males and six females each): Group A (control), Group B (supplemented with T. molitor larvae at 10%), Group C (supplemented with chitosan at 0.05%), and Group D (supplemented with both ingredients at 10% and 0.05%, respectively). On the 42nd day of the experimental trial, samples of blood, feces, and carcass parts were taken for analysis. The results indicated that the insect larvae meal significantly improved (p < 0.05) overall performance, increased (p < 0.05) blood red blood cell content, increased meat phenolic content (p < 0.05), improved meat oxidative stability (p < 0.05), and affected meat fatty acid profile (p < 0.05). On the other hand, chitosan had no significant effect on overall performance (p > 0.05), but it significantly increased blood lymphocyte content (p < 0.05), affected the fecal microbiota (p < 0.05), improved meat oxidative stability (p < 0.05), increased meat phenolic content (p < 0.05), and affected meat fatty acid composition (p < 0.05) and (p < 0.05) meat color. Finally, the combined use of both T. molitor and chitosan significantly affected some important zootechnical parameters (p < 0.05), fecal microbial populations (p < 0.05), meat color (p < 0.05), and fatty acid profile (p < 0.05). Further investigation into the potential interaction between insect larvae meals and chitosan in pig diets is advised.

Modification of the terms of authorisation regarding the additive consisting of liquid l-lysine base produced with Corynebacterium glutamicum NRRL B-67439 and NRRL B-67535 for all animal species (ADM specialty ingredients (Europe) B.V.).

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of liquid l-lysine base produced with a genetically modified strain of Corynebacterium glutamicum as a nutritional feed additive for all animal species. The l-lysine base liquid produced with C. glutamicum NRRL B-67535 and NRRL B-67439 is currently authorised as a nutritional additive for all animal species. The present application is aimed at modifying the current authorisation to include C. glutamicum NRRL B-68248 as a production strain. The new production strain qualifies for the qualified presumption of safety approach when used for production purposes. It was unambiguously identified as C. glutamicum and was shown not to harbour acquired antimicrobial resistance determinants for antibiotics of human and veterinary importance. All the introduced sequences or mutations were considered to be safe, and no viable cells or DNA of the NRRL B-68248 strain was detected in the final product. Therefore, the final product does not pose any safety concern associated with the production strain. l-Lysine base produced using C. glutamicum NRRL B-68248 does not represent a risk for the target species, the consumer or the environment. The additive was considered to be neither irritant to skin or the eyes, nor a dermal sensitiser. l-Lysine base produced with C. glutamicum NRRL B-68248 is considered to be an efficacious source of the essential amino acid l-lysine for non-ruminant animal species. For the supplemental l-lysine to be as efficacious in ruminants as in non-ruminant species, it would require protection against degradation in the rumen.

Safety of a feed additive consisting of 3-phytase produced with Komagataella phaffii CECT 13171 (FSF10000/FLF1000) for poultry species, pigs for fattening and minor porcine species for fattening (Fertinagro Biotech S.L.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety of the feed additive consisting of 3-phytase produced with a genetically modified strain of Komagataella phaffii (CECT 13171). The additive is intended to be used as a zootechnical additive for poultry species, pigs for fattening and minor porcine species for fattening. In a previous opinion, the EFSA Panel on Additives and Products or Substance used in Animal Feed (FEEDAP) Panel could not conclude on the taxonomic identification of the production strain. Moreover, the presence of viable cells of the production strain in the final formulations of the product could not be excluded. Therefore, no conclusions could be drawn on the safety for the target species, consumers, users and environment. In the present submission, the applicant provided supplementary information regarding the characterisation of the production strain and the absence of its viable cells in the final product. Based on the data provided, the identification of CECT 13171 as K. phaffii was confirmed and no viable cells of the production strain were detected in the final formulations of the additive. The FEEDAP Panel concluded that the 3-phytase produced with the genetically modified strain K. phaffii CECT 13171 does not give rise to any safety concern as regard to the production strain. Consequently, the additive, in both its liquid and solid formulations, is safe for the target species, consumers, users and environment.

Safety and efficacy of a feed additive consisting of l-valine produced with Escherichia coli CGMCC 22721 for all animal species (Eppen Europe SAS).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of l-valine produced by fermentation with a genetically modified strain of Escherichia coli (CGMCC 22721) as a nutritional additive for all animal species. The production strain and its DNA were not detected in the final additive. Therefore, the final product does not give raise to any safety concern regarding the genetic modification of the production strain. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concludes that l-valine produced using E. coli CGMCC 22721 is safe for the target species when supplemented in appropriate amounts to the diet according to the nutritional needs of the target species. The FEEDAP Panel has concerns on the use of amino acids in water for drinking for hygienic reasons, and due to the risk of imbalances when administered simultaneously via feed. The use of l-valine produced using E. coli CGMCC 22721 in animal nutrition is considered safe for the consumers and for the environment. The FEEDAP Panel cannot conclude on the potential of l-valine produced using E. coli CGMCC 22721 to irritant to the skin or eyes, a dermal or respiratory sensitiser due to the lack of data. The endotoxin activity of the additive does not represent a hazard for users handling the additive when exposed by inhalation. The additive l-valine produced by fermentation using E. coli CGMCC 22721 is regarded as an efficacious source of the essential amino acid l-valine for non-ruminant nutrition. For the supplemental l-valine to be as efficacious in ruminants as in non-ruminant species, it requires protection against degradation in the rumen.

Safety and efficacy of a feed additive consisting of l-arginine produced with Escherichia coli CGMCC 7.401 for all animal species (Eppen Europe SAS).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of the feed additive consisting of l-arginine produced by fermentation with a genetically modified strain of Escherichia coli (CGMCC 7.401). The additive is intended to be used in feed and water for drinking for all animal species and categories. The genetic modifications introduced do not raise safety concerns. No viable cells or DNA of the production strain were detected in the final product. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive does not pose any safety concern with regard to the production strain. l-Arginine produced with E. coli CGMCC 7.401 is safe for the target species when supplemented in appropriate amounts to the diet according to the nutritional needs of the target species. The FEEDAP Panel has concerns on the use of amino acids in water for drinking for hygienic reasons, and due to the risk of imbalances when administered simultaneously via feed and water. The use of l-arginine produced with E. coli CGMCC 7.401 in animal nutrition is considered safe for the consumers and for the environment. The endotoxin activity of the additive does not represent a hazard for persons handling the additive. In the absence of data, the FEEDAP Panel cannot conclude on the potential of the additive to be irritant to skin and/or eyes, or to be a dermal or respiratory sensitiser. The additive l-arginine produced with E. coli CGMCC 7.401 is regarded as an efficacious source of the essential amino acid l-arginine for non-ruminant species. For supplemental l-arginine to be as efficacious in ruminants as in non-ruminant species, it requires protection against degradation in the rumen.

Assessment of the feed additive consisting of endo-1,4-beta-xylanase (produced with Trichoderma reesei MUCL 49755) and endo-1,3(4)-beta-glucanase (produced with T. reesei MUCL 49754) (AveMix® XG 10) for pigs for fattening, minor porcine species for fattening and turkeys for fattening for the renewal of its authorisation (AVEVE BV).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the feed additive consisting of endo-1,4-beta-xylanase (produced with Trichoderma reesei MUCL 49755) and endo-1,3(4)-beta-glucanase (produced with T. reesei MUCL 49754) (AveMix® XG 10/AveMix® XG 10 L) for the renewal of its authorisation as zootechnical feed additive for pigs for fattening, minor porcine species for fattening and turkeys for fattening. The applicant declared a change in the carrier material used in AveMix® XG 10 from soybean meal to calcium carbonate + wheat flour or calcium carbonate + sepiolite. The applicant provided evidence that the additive Avemix® XG 10 with calcium carbonate + wheat flour and Avemix® XG 10 L comply with the conditions of the authorisation. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) noted that no data were submitted to support compliance of the formulation of Avemix® XG 10 with calcium carbonate + sepiolite with the conditions of the authorisation. The FEEDAP Panel concluded that both forms of the additive remain safe for pigs for fattening, minor porcine species for fattening and turkeys for fattening, consumers and the environment. Regarding the safety for the user, Avemix® XG 10 formulated with calcium carbonate + sepiolite and Avemix® XG 10 L are not irritant to skin and eyes. No conclusions on the irritation potential of Avemix® XG 10 formulated with calcium carbonate + wheat flour could be drawn. The additive in all its formulations is considered a respiratory and skin sensitiser. There was no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Assessment of the feed additive consisting of Levilactobacillus brevis DSM 16680 for all animal species for the renewal of its authorisation (Microferm Ltd.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application of renewal of Levilactobacillus brevis DSM 16680 as a technological feed additive (functional group: silage additives) for all animal species. The applicant has provided evidence that the additive currently on the market complies with the existing terms of the authorisation. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive remains safe for all animal species, consumers and the environment. Regarding user safety, the additive should be considered as an eye irritant and a skin and respiratory sensitiser. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Safety and efficacy of a feed additive consisting of an essential oil derived from the leaves of Salvia officinalis ssp. lavandulifolia (Vahl) Gams (Spanish sage oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Spanish sage oil from the leaves of Salvia officinalis ssp. lavandulifolia (Vahl) Gams (Spanish sage oil) when used as a sensory additive in feed and in water for drinking for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive under assessment is considered safe up to the maximum use level of 14 mg/kg complete feed for all animal species. The FEEDAP Panel considered that the use of Spanish sage oil in water for drinking is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. The use of Spanish sage oil in animal feed under the proposed conditions of use is safe for the consumer and the environment. Regarding user safety, the essential oil under assessment should be considered as an irritant to skin and eyes and as a dermal and respiratory sensitiser. Since the oil of the leaves of S. officinalis ssp. lavandulifolia (Vahl) Gams is recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Assessment of the feed additive consisting of a preparation containing a smoke flavouring extract for cats and dogs for the renewal of the authorisation (Azelis Denmark A/S).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for the renewal of authorisation of a preparation containing a smoke flavouring extract for cats and dogs. The applicant provided data demonstrating that the additive currently on the market does not fully comply with the conditions of authorisation, but with newly proposed specifications based on different analytical methods. Considering that the additive under assessment contains benzofuran and styrene, for which a potential concern for genotoxicity has been identified, and that the whole mixture raises a potential concern for genotoxicity, additional data would be needed to complete the assessment. Therefore, the FEEDAP Panel is not in the position to conclude on the safety for cats and dogs. The additive is authorised for use in feed for cats and dogs, and therefore, there is no need to perform an assessment of the safety for the consumer and the environment. Regarding user safety, the additive should be considered as irritant to skin and eyes, and as a dermal and respiratory sensitiser. When handling the additive, exposure of unprotected users to potential genotoxic substances may occur. Therefore, to reduce the risk, the exposure of the users should be minimised. There was no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Safety and efficacy of a feed additive consisting of Saccharomyces cerevisiae NCYC R618 (Benesacc®) for chickens for fattening and other poultry species for fattening and reared for laying (Global Nutritech Biyoteknoloji Ltd. Sti).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Saccharomyces cerevisiae NCYC R618 as a zootechnical feed additive (functional group: gut flora stabiliser) for chickens for fattening and other poultry species for fattening and reared for laying. The additive has never been authorised. The strain under assessment S. cerevisiae (NCYC R618) qualifies for the qualified presumption of safety (QPS) and, consequently, the FEEDAP Panel concluded that the product is safe for the target species, the consumers and the environment. The FEEDAP Panel could not conclude on the skin and eye irritation or skin sensitisation potential of the additive. The additive should be considered a respiratory sensitiser. Due to the lack of sufficient data, the Panel cannot conclude on the efficacy of the additive under the proposed conditions of use.

Assessment of the feed additive consisting of sodium propionate for all terrestrial animal species for the renewal of its authorisation (BASF SE).

Sodium propionate is authorised containing at least 98.5% of sodium propionate. The applicants requested for the renewal of the authorisation of sodium propionate when used as a feed additive for all terrestrial animal species. The applicant has provided evidence that the additive in the market complies with the conditions of the authorisation. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP Panel) confirms that the use of sodium propionate under the current authorised conditions of use is safe for the target species, the consumers and the environment. Considering the user safety, the additive is corrosive to skin, eyes and respiratory tract, but is not a skin sensitiser. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Safety and efficacy of a feed additive consisting of Lentilactobacillus buchneri DSM 32651 for all animal species (BioCC OÜ).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of Lentilactobacillus buchneri DSM 32651 when used as a technological additive to improve ensiling of fresh plant material. The additive is intended for use in all fresh material for all animal species at a proposed minimum concentration of 1 × 108 colony forming units (CFU)/kg fresh plant material. The bacterial species L. buchneri is considered by EFSA to be suitable for the qualified presumption of safety approach to safety assessment. The identity of the strain was established and no acquired antimicrobial resistance genes of concern were detected. Therefore, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the use of the strain as a silage additive is considered safe for all the animal species, for consumers of products from animals fed the treated silage and for the environment. Regarding user safety, the additive should be considered as a potential skin and respiratory sensitiser, and any exposure through skin and respiratory tract is considered a risk. The additive is not an eye irritant. The FEEDAP Panel concluded that the additive consisting of L. buchneri DSM 32651 at a minimum concentration of 1 × 108 CFU/kg fresh material may extend the aerobic stability of silage prepared from fresh plant material with a DM range of 28%-45%.

Assessment of the feed additive consisting of propionic acid for all terrestrial animal species for the renewal of its authorisation (Eastman Chemical B.V., Perstorp AB, Dow Europe GmbH, BASF SE).

Propionic acid is currently authorised as a technological additive (functional group: silage additives) for all animal species. The applicants requested for the renewal of the authorisation of propionic acid when used as a feed additive for all terrestrial animal species. The applicants have provided evidence that the additive in the market complies with the conditions of the authorisation. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP Panel) confirms that the use of propionic acid under the current authorised conditions of use is safe for the target species, the consumers and the environment. Regarding user safety, the additive is corrosive to the skin and any exposure to users is considered a risk. There is no need for assessing the efficacy of the additive in the context of the renewal of the authorisation.

Safety and efficacy of a feed additive consisting of a Camellia oleifera C.Abel seed extract for use in all animal species except fin fish (NOR-FEED SAS).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a Camellia oleifera C.Abel seed extract (Cosap®) as technological feed additive for all animal species except fin fish. In the absence of adequate tolerance studies in the target species or toxicological studies with the additive under assessment, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) could not conclude on the safety of C. oleifera extract for the target species. The use of the additive in animal nutrition is not expected to cause concern for consumer safety. The additive is considered as irritant to the eyes and mucous membranes. No conclusions can be reached on the potential of the additive to be irritant to the skin or to be a dermal sensitiser. The use of the additive under the proposed conditions of use is considered safe for the terrestrial compartment. However, no conclusion can be reached on the safety of the additive for the environment when used in feed of aquatic animals other than fin fish. The Panel concluded that the additive has the potential to be efficacious as an emulsifier when used according to proposed conditions of use.

Safety and efficacy of a feed additive consisting of fumaric acid for all animal species for the renewal of its authorisation and extension of use (Life SUPPLIES NV).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for the renewal of the authorisation of fumaric acid as a technological and sensory additive (functional groups: preservative and flavouring compounds, respectively) and for a new use of the additive as a technological additive (functional group: acidity regulator) for all animal species. The applicant provided evidence that the additive currently in the market complies with the existing conditions of authorisation. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that fumaric acid remains safe under the authorised conditions of use for the terrestrial animals, consumers and the environment. However, the Panel cannot conclude on the safety for the aquatic animals under all authorised condition of use. Fumaric acid is irritant to skin, eyes and respiratory tract, and should be considered a skin and respiratory sensitiser due to the presence of nickel. The Panel also considers that the new use of the additive as an acidity regulator under proposed conditions of use would not introduce risks not already considered. There is no need to assess the efficacy of the additive in the context of the renewal of the authorisation (for its use as preservative and flavouring compound). The Panel is not in the position to conclude on the efficacy of fumaric acid as an acidity regulator in feed.

Safety and efficacy of a feed additive consisting of endo-1,4-ß-xylanase produced with Trichoderma reesei CBS 114044 (ECONASE® XT) for pigs for fattening, laying hens and minor poultry species (AB Enzymes Finland Oy).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a product containing endo-1,4-ß-xylanase (ECONASE® XT) as a zootechnical feed additive (digestibility enhancer) for pigs for fattening, laying hens and minor poultry species. ECONASE® XT is available in two liquid and three solid forms and is produced with a genetically modified strain of Trichoderma reesei (CBS 114044). The FEEDAP Panel concluded that the genetic modification of the production strain does not raise any safety concerns, and viable cells of the production strain and its DNA were not detected in the final products. The Panel also concluded that ECONASE® XT is safe for pigs for fattening, laying hens and minor poultry species at the proposed conditions of use. The use of the additive raises no safety concerns for the consumers of products derived from animals fed with the additive or for the environment. The liquid and solid forms of ECONASE® XT are non-irritant to the skin, but only the liquid forms were confirmed as non-irritant to the eyes and not dermal sensitisers. The Panel could not conclude on the irritation potential to the eyes and the dermal sensitisation potential for the solid forms. Due to the proteinaceous nature of the active substance, the additive is considered to be a respiratory sensitiser. The additive has the potential to be efficacious in pigs for fattening at 20,000 BXU/kg complete feed, in all laying poultry species at 12,000 BXU/kg complete feed and in minor poultry species other than laying birds at 8000 BXU/kg complete feed.

Functional properties of carotenoids originating from algae.

Carotenoids are isoprenoid molecules which are synthesised de novo by photosynthetic plants, fungi and algae and are responsible for the orange, yellow and some red colours of various fruits and vegetables. Carotenoids are lipophilic compounds, some of which act as provitamins A. These compounds can be divided into xanthophylls and carotenes. Many macroalgae and microalgae are rich in carotenoids, where these compounds aid in the absorption of sunlight. Industrially, these carotenoids are used as food pigments (in dairy products, beverages, etc.), as feed additives, in cosmetics and in pharmaceuticals, especially nowadays when there is an increasing demand by consumers for natural products. Production of carotenoids from algae has many advantages compared to other sources; for example, their production is cheap, easy and environmentally friendly; their extraction is easier, with higher yields, and there is no lack of raw materials or limited seasonal variation. Recently, there has been considerable interest in dietary carotenoids with respect to their antioxidant properties and their ability to reduce the incidence of some chronic diseases where free radicals are involved. Possibly, carotenoids protect cells from oxidative stress by quenching singlet oxygen damage with various mechanisms. Therefore, carotenoids derived from algae could be a leading natural resource in the research for potential functional ingredients.

Growth performance, welfare traits and meat characteristics of broilers fed diets partly replaced with whole Tenebrio molitor larvae.

The role of insects in animal nutrition has been reconsidered during recent years, paving the way for an increasing market for edible insects. Their protein and amino acid balance make them a promising source of protein for replacing high value proteins. Yellow mealworm, Tenebrio molitor L. (TM; Coleoptera: Tenebrionidae) larvae, have shown positive effects on broiler performance in several research studies and have a strong potential as a sustainable alternative protein source for monogastric animals. This study aimed to assess the effect of replacing various ratios of basal diets with T. molitor larvae on broiler performance as well as on several meat and welfare characteristics. For the study, 120 one-day-old male chicks (Ross 308) were randomly allocated in 3 treatments and 4 replications (10 birds per pen). Birds of the control group (basal diet) were fed with typical commercial maize and soymeal-based rations in mash form. The other 2 groups were treated with the same diet, after replacing 5% and 10% with dried TM larvae, respectively. On d 35 (end of trial), meat samples were collected and analysed. Body weight, feed intake, body weight gain and feed conversion ratio during the periods of 1 to 10 d (starter period), 11 to 24 d (grower period), 25 to 35 d (finisher period) and 1 to 35 d (total period) were assessed. Pododermatitis, diarrhoea, feather score and litter conditions were also assessed during the trial. The results indicated that TM larvae inclusion in the broilers' diet positively affected body weight gain values, as well as the carcass yield, the meat composition and various welfare traits. Additionally, the dietary treatments with TM larvae favourably affected meat composition and colour parameters, whereas there were also some positive effects on lipid and protein oxidation. Saturated fatty acids were decreased by the dietary supplementation whereas the polyunsaturated fatty acids to SFA ratio increased. In general, the study showed that whole TM larvae addition can provide a promising alternative to soybean meal in the diet of broilers, demonstrating a positive impact on growth, welfare and meat characteristics.