Poultry Species Research Articles

Proximate Chemical Analysis and Deterioration Criteria of Goose Giblets

Goose meat is one of the most common types of meat consumed worldwide. Egyptian goose species, known as Alopochen aegyptiacus is one of the first reared poultry species. As meat consumption and the need for animal protein rise globally, edible giblets can serve as abundant protein and fat sources. Recently, edible giblets have become readily available, quick-to-prepare food on the market. This study aimed to reveal the proximate chemical composition (protein, fat, moisture, and ash) as well as the deterioration criteria (pH, Total volatile basic nitrogen [TVBN] value, and thiobarbituric acid reactive substance [TBA] value) of Egyptian goose giblets, including liver, gizzard, and heart. A total of 60 samples of goose giblets, including liver, gizzard, and heart (n = 20 each), were collected from Giza and Cairo cities, Egypt. The results showed a marked variation among each giblet type. The goose’s highest protein content (24.48%), moisture content (72.42%), and fat content (12.18%) were recorded for liver, gizzard, and heart, respectively. Moreover, the highest pH (6.72) and TVBN mean value (5.61 mg/100 gm) were indicated in goose’s livers, while the highest TBA mean (0.67 mg malonaldehyde/kg) was obtained from goose’ hearts. These findings may provide a clear understanding for both consumers and possessors about the nutritional value of goose giblets which could be used as an alternative protein source. Moreover, the obtained data in the current study could help meat technology processors to add nutritional value to goose products using goose giblets.

Effect of Sperm Cryopreservation in Farm Animals Using Nanotechnology.

Simple SummaryOptimum production from farm animals can be achieved by focusing on all aspects, including reproduction in male stock. Sperm cryopreservation is a commonly practiced technique to preserve the semen of highly productive males. Semen should be collected and stored with utmost care because various factors affect their quality after collection, including the handling and cryodamage of sperm. It lowers semen quality, resulting in economic loss and low productivity. The present review paper focuses on advancements in semen cryopreservation in farm animals and methods for avoiding sperm cryodamage.Sperm cryopreservation is one of the sublime biotechnologies for assisted reproduction. In recent decades, there has been an increasing trend in the use of preserved semen. Post-thaw semen quality and values vary among animals of the same species. Similarly, there are species-specific variations in sperm morphology, i.e., sperm head, kinetic properties, plasma membrane integrity, and freezability. Similarly, the viability of sperm varies in the female reproductive tract, i.e., from a few hours (in cattle) to several days (in chicken). Various steps of sperm cryopreservation, i.e., male health examination, semen collection, dilution, semen centrifugation, pre- and post-thaw semen quality evaluation, lack standardized methodology, that result in differences in opinions. Assisted reproductive technologies (ART), including sperm preservation, are not applied to the same extent in commercial poultry species as in mammalian species for management and economic reasons. Sperm preservation requires a reduction in physiological metabolism by extending the viable duration of the gametes. Physiologically and morphologically, spermatozoa are unique in structure and function to deliver paternal DNA and activate oocytes after fertilization. Variations in semen and sperm composition account for better handling of semen, which can aid in improved fertility. This review aims to provide an update on sperm cryopreservation in farm animals.

Safety and efficacy of a feed additive consisting of a preparation of carvacrol, thymol, d-carvone, methyl salicylate and l-menthol (Biomin®DC-P) for all poultry species (Biomin GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a preparation of carvacrol, thymol, d‐carvone, methyl salicylate and l‐menthol (Biomin® DC‐P) for all poultry species. The additive is authorised for use in feed for chickens for fattening, chickens reared for laying and minor poultry species reared to the point of lay. The safety and efficacy of the additive for those species have been previously evaluated by the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP Panel). The current application is for an extension of use of the additive for all poultry species under the same conditions of use (recommended level ranging between 65 and 105 mg/kg complete feed). The FEEDAP Panel concluded that the additive Biomin® DC‐P is safe for poultry species for fattening or reared for laying, but in the absence of adequate data cannot conclude on the safety for laying/breeding birds. The use of Biomin® DC‐P in feed for all poultry species under the proposed conditions of use was considered safe for consumers and the environment. The FEEDAP Panel considered that exposure of users by inhalation is unlikely. In the absence of data, the Panel could not conclude on the effects of Biomin® DC‐P on skin and eyes. Biomin® DC‐P has the potential to be efficacious in poultry species for fattening or reared for laying when incorporated into feed at a minimum concentration of 65 mg/kg complete feed. In the absence of sufficient data, the Panel could not conclude on the efficacy for laying hens or for other poultry species for laying/breeding.

Molecular prevalence of Tetratrichomonas gallinarum and Trichomonas gallinae in three domestic free-range poultry breeds in Anhui Province, China.

Tetratrichomonas gallinarum and Trichomonas gallinae can colonize the alimentary tract of domestic birds. However, little information is available on the epidemiology of the two trichomonad species in domestic free-range poultry in China. In this study, the occurrence and genetic characteristic of T. gallinarum and T. gallinae among free-range chickens, ducks, and geese in Anhui Province, China, were investigated. The 1910 fecal samples collected from 18 free-range poultry farms throughout Anhui Province were examined for the presence of T. gallinarum and T. gallinae by PCR and sequence analysis of the small subunit (SSU) rRNA gene of T. gallinarum and ITS1-5.8S-ITS2 sequence of T. gallinae. The overall occurrence of T. gallinarum in poultry was 1.2% (22/1910), with infection rates of 2.1% (17/829) in chickens, 0.2% (1/487) in ducks, and 0.7% (4/594) in geese. The constructed phylogeny tree using the concatenated ITS1-5.8S-ITS2 region and SSU rRNA indicated the T. gallinarum isolates detected in this study were closely related to previously defined genogroups A, D, and E, respectively. Nine (0.5%) fecal samples were positive for T. gallinae, with infection rates of 0.8% (7/829) in chickens, 0.4% (2/487) in ducks, and 0% (0/594) in geese. Sequence and phylogenetic analysis showed that four T. gallinae ITS1-5.8S-ITS2 sequences obtained from chicken feces and one duck fecal sample belonged to genotype ITS-OBT-Tg-1. This is the first report of the prevalence and genetic characterization of T. gallinarum and T. gallinae in free-range chickens, ducks, and geese in China.

Village and farm-level risk factors for avian influenza infection on backyard chicken farms in Bangladesh

A cross-sectional study was conducted with 144 small-scale poultry farmers across 42 Bangladeshi villages to explore risk factors associated with avian influenza H5 and H9 seropositivity on backyard chicken farms. Using mixed-effects logistic regression with village as random effect, we identified crow abundance in garbage dumping places and presence of migratory wild birds within villages to be associated with higher odds of H5 and H9 seropositivity. At farm-level, garbage around poultry houses was also associated with higher odds of H5 and H9 seropositivity. In addition, specific trading practices (such as, purchase of chickens from live bird markets (LBM) and neighboring farms to raise them on their own farms, frequency of visits to LBM, purchase of poultry at LBM for consumption) and contact of backyard chickens with other animals (such as, feeding of different poultry species together, using pond water as drinking source for poultry, access of feral and wild animals to poultry houses) were associated with higher odds of H5 or H9 seropositivity. Resource-constrained small-scale poultry farmers should be able to address risk factors identified in this study without requiring large investments into poultry management, thereby reducing the likelihood of avian influenza virus transmission and ultimately occurrence of avian influenza outbreaks.

Comparative characteristics of the sensitivity of the bird to aspergillosis pathogens

It has been established that the most common mycoses among poultry are aspergillosis and mucormycosis, which are observed in sporadic cases under conditions of violation of egg incubation technologies, zoohygienic conditions for poultry keeping, and feed storage. Aspergillosis (pneumomycosis, brood pneumonia, mycosis) is an infectious disease that most often affects the respiratory system and, less often, the serous membranes of other organs, namely the liver, intestines, spleen, kidneys, central nervous system, and air cavities of the tubular bones. Aspergillosis affects all species of poultry and wild birds. The disease is more common in young animals in the first days of life. In the studied poultry farms, aspergillosis has a different intensity. The disease can kill 30 to 50 % of all young animals and, in some cases, only a few. This is due to the infection of the fungus in the environment, its pathogenicity, the bird's age, and its resistance. The material for the research was carcasses and aspergillosis-sick birds from Poltava HPE LLC, Poltava Poultry Factory JSC, Poltava Incubator Agricultural Complex, and Poltava district private farms. Statistical indicators from the surveyed farms and micro-sections. It has been established that the causative agent of aspergillosis in chickens and young guinea fowl is mainly the fungus Aspergillus fiimigatus, less often Aspergillus flavus. Sources of infection in the surveyed farms are infected hatching eggs infected with fungal spores and moldy litter. Determining factors contributing to the infection are unsatisfactory conditions for keeping young birds: high humidity and faulty ventilation system. Chickens are more sensitive to aspergillosis than young guinea fowl because, for chickens, the number of detected pathologies in various organs and systems is much higher. The disease in chickens is superacute, acute, and chronic; in young guinea fowl, it is in a mild form (without chronic forms). Clinical signs of avian aspergillosis are not typical, which complicates the lifelong diagnosis of the disease. The results show that raising guinea fowl is a more profitable business because the rate of loss of young is much lower than that of chickens and the rate of sexual maturity for guinea fowl is also higher. Aspergillosis in one-three-day-old chickens is characterized by serous tracheitis, bronchitis, aerosacculitis, and serous fungal pneumonia. Histological examination of the lungs showed swelling of endothelial and alveolar cells, the presence of fungal spores in blood vessels, necrosis, and desquamation of the respiratory epithelium.

Characteristics of Indigenous Ducks and Their Production System in Nigeria: A Review

Indigenous ducks are important biodiversity resources and genetic reservoirs needed for mitigating future challenges of food insecurity even though they are highly prejudiced in some parts of Nigeria. They can compare favourably with chickens to produce meat and egg, can adapt to different climatic conditions since raising them does not require elaborate houses. These ducks are known for their high hatching rate that is higher than any other local poultry species and also have the potential to perform better under improved management systems. Average body weight of 2.7 and 1.6 kg have been reported for drakes and females respectively, egg weight of about 50-60 g have equally been reported. Each duck can lay between 60-80 eggs annually under scavenging conditions, while meat from duck is rich in unsaturated fatty acids which are advantageous for human health. Wide variations in phenotypic traits and also high genetic diversity exist among ducks. Thus the findings of this paper suggest that the genetic makeup of these ducks have not been altered through selective breeding therefore, their genetic improvement and conservation is highly essential towards achieving food security.

Protective Efficacy of H9N2 Avian Influenza Vaccines Inactivated by Ionizing Radiation Methods Administered by the Parenteral or Mucosal Routes.

H9N2 viruses have become, over the last 20 years, one of the most diffused poultry pathogens and have reached a level of endemicity in several countries. Attempts to control the spread and reduce the circulation of H9N2 have relied mainly on vaccination in endemic countries. However, the high level of adaptation to poultry, testified by low minimum infectious doses, replication to high titers, and high transmissibility, has severely hampered the results of vaccination campaigns. Commercially available vaccines have demonstrated high efficacy in protecting against clinical disease, but variable results have also been observed in reducing the level of replication and viral shedding in domestic poultry species. Antigenic drift and increased chances of zoonotic infections are the results of incomplete protection offered by the currently available vaccines, of which the vast majority are based on formalin-inactivated whole virus antigens. In our work, we evaluated experimental vaccines based on an H9N2 virus, inactivated by irradiation treatment, in reducing viral shedding upon different challenge doses and compared their efficacy with formalin-inactivated vaccines. Moreover, we evaluated mucosal delivery of inactivated antigens as an alternative route to subcutaneous and intramuscular vaccination. The results showed complete protection and prevention of replication in subcutaneously vaccinated Specific Pathogen Free White Leghorn chickens at low-to-intermediate challenge doses but a limited reduction of shedding at a high challenge dose. Mucosally vaccinated chickens showed a more variable response to experimental infection at all tested challenge doses and the main effect of vaccination attained the reduction of infected birds in the early phase of infection. Concerning mucosal vaccination, the irradiated vaccine was the only one affording complete protection from infection at the lowest challenge dose. Vaccine formulations based on H9N2 inactivated by irradiation demonstrated a potential for better performances than vaccines based on the formalin-inactivated antigen in terms of reduction of shedding and prevention of infection.

Insights into Genetic Characteristics and Virological Features of Endemic Avian Influenza A (H9N2) Viruses in Egypt from 2017-2021.

From 2010 to 2013, genotype I avian influenza A(H9N2) viruses of the G1-lineage were isolated from several poultry species in Egypt. In 2014, novel reassortant H9N2 viruses were detected in pigeons designated as genotype II. To monitor the subsequent genetic evolution of Egyptian A(H9N2) viruses, we characterized the full genomes of 173 viruses isolated through active surveillance from 2017 to 2022. In addition, we compared the virological characteristics and pathogenicity of representative viruses. Phylogenetic analysis of the HA indicated that all studied sequences from 2017–2021 were grouped into G1-like H9N2 viruses previously detected in Egypt. Phylogenetic analysis indicated that the Egyptian A(H9N2) viruses had undergone further reassortment, inheriting four genes (PB2, PB1, PA, NS) from genotype II, with their remaining segments deriving from genotype I viruses (these viruses designated as genotype III). Studying the virological features of the two most dominant genotypes (I and III) of Egyptian H9N2 viruses in vitro and in vivo indicated that both replicated well in mammalian cells, but did not show any clinical signs in chickens, ducks, and mice. Monitoring avian influenza viruses through surveillance programs and understanding the genetic and antigenic characteristics of circulating H9N2 viruses are essential for risk assessment and influenza pandemic preparedness.

Adenoviral associated gizzard erosions: an overview and case example

Adenoviruses are of increasing concern in both human and veterinary medicine. The effects of adenoviruses in poultry species have been well documented for many decades. Adenoviral gizzard erosion (AGE) is one such syndrome that affects chickens and is caused by members of group A of the fowl adenoviruses. Development of clinical AGE is poorly understood, but cases of this syndrome can lead to economic losses and welfare concerns in both broiler and layer populations. Clinical signs, gross post-mortem lesions and histological lesions can all be used to help identify cases of AGE in practice. This article will explore AGE in the context of clinical poultry practice, including an overview of the aetiology, transmission, clinical signs, diagnosis and control of AGE.

Study on the Raman spectral characteristics of dynamic and static blood and its application in species identification.

This paper proposes a method to identify the blood of 4 poultry species (chicken, duck, goose and pigeon) based on Raman spectroscopy and its baseline. Samples were prepared by pretreatment methods of freezing, thawing, and dilution. The Raman spectra of dynamic blood and static blood were measured, respectively, and the spectral differences between the two research schemes were analyzed. The four species of poultry blood were identified based on the Raman spectroscopy and its baseline. The results show that the method can realize the identification of four species of poultry blood. In addition, the potential of Raman spectroscopy as a technique for determining carotenoids in blood has been clearly confirmed, which opens up the possibility to quickly determine whether poultry eats feed containing carotenoids without sample preparation.

Safety and efficacy of a feed additive consisting of endo-1,4-β-xylanase produced by Komagataella phaffiiATCC PTA-127053 (Xygest™ HT) for poultry (Kemin Europa N.V.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of endo‐1,4‐β‐xylanase produced by Komagataella phaffii ATCC PTA‐127053 (Xygest™ HT) as a zootechnical feed additive for poultry. The production strain is genetically modified. No viable cells nor recombinant DNA of the production strain were detected in the final product. Therefore, the Panel concluded that the additive does not pose any safety concern regarding the production strain. The FEEDAP Panel concluded that Xygest™ HT is considered safe for chickens for fattening at 30,000 U/kg and in laying hens at 45,000 U/kg, with a wide margin of safety. These conclusions can be extended to chickens reared for laying/breeding and extrapolated to all poultry species for fattening and reared for laying/breeding and to ornamental birds. The conclusions on laying hens are extrapolated to all laying poultry species. The use of Xygest™ HT in animal nutrition is of no concern for consumer safety and this feed additive is considered safe for the environment. The Panel also concluded that Xygest™ HT is not irritant to the eyes and skin but should be considered a dermal and a respiratory sensitiser. The Panel concluded that the additive Xygest™ HT has a potential to be efficacious for laying hens under the proposed conditions of use and this conclusion can also be extrapolated to all laying poultry species. The Panel could not conclude on the efficacy of the product for chickens for fattening due to insufficient data.

Practical application of a Bayesian network approach to poultry epigenetics and stress

BackgroundRelationships among genetic or epigenetic features can be explored by learning probabilistic networks and unravelling the dependencies among a set of given genetic/epigenetic features. Bayesian networks (BNs) consist of nodes that represent the variables and arcs that represent the probabilistic relationships between the variables. However, practical guidance on how to make choices among the wide array of possibilities in Bayesian network analysis is limited. Our study aimed to apply a BN approach, while clearly laying out our analysis choices as an example for future researchers, in order to provide further insights into the relationships among epigenetic features and a stressful condition in chickens (Gallus gallus).ResultsChickens raised under control conditions (n = 22) and chickens exposed to a social isolation protocol (n = 24) were used to identify differentially methylated regions (DMRs). A total of 60 DMRs were selected by a threshold, after bioinformatic pre-processing and analysis. The treatment was included as a binary variable (control = 0; stress = 1). Thereafter, a BN approach was applied: initially, a pre-filtering test was used for identifying pairs of features that must not be included in the process of learning the structure of the network; then, the average probability values for each arc of being part of the network were calculated; and finally, the arcs that were part of the consensus network were selected. The structure of the BN consisted of 47 out of 61 features (60 DMRs and the stressful condition), displaying 43 functional relationships. The stress condition was connected to two DMRs, one of them playing a role in tight and adhesive intracellular junctions in organs such as ovary, intestine, and brain.ConclusionsWe clearly explain our steps in making each analysis choice, from discrete BN models to final generation of a consensus network from multiple model averaging searches. The epigenetic BN unravelled functional relationships among the DMRs, as well as epigenetic features in close association with the stressful condition the chickens were exposed to. The DMRs interacting with the stress condition could be further explored in future studies as possible biomarkers of stress in poultry species.

Genome organization of major tandem repeats and their specificity for heterochromatin of macro- and microchromosomes in Japanese quail.

Tandemly repeated DNAs form heterochromatic regions of chromosomes, including the vital centromeric chromatin. Despite the progress in new genomic technologies, tandem repeats remain poorly deciphered and need targeted analysis in the species of interest. The Japanese quail is one of the highest-producing poultry species as well as a model organism. Its genome differs by a noticeable accumulation of heterochromatin, which led to an increase by 1/7 compared to the chicken genome size. Prominent heterochromatin blocks occupy the short arms of acrocentric macrochromosomes and of microchromosomes. We have applied de novo repeat finder approach to unassembled raw reads of the Japanese quail genome. We identified the 20 most common tandem repeats with the abundance >1Mb, which represent about 4.8% of the genome. We found that tandem repeat CjapSAT primarily contributes to the centromeric regions of the macrochromosomes CJA1-8. Cjap31B together with previously characterized BglII makes up centromere regions of microchromosomes and W chromosome. Other repeats populate heterochromatin of microchromosomal short arms in unequal proportions, as revealed by fluorescence in situ hybridization. The Cjap84A, Cjap408A, and CjapSAT repeat sequences show similarities to retrotransposon motifs. This suggests that retroelements may have played a crucial role in the distribution of repeats throughout the Japanese quail genome.

Safety and efficacy of a feed additive consisting of endo-1,4-β-xylanase produced by Komagataella phaffiiDSM 33574 (Xylamax) for chickens and turkeys for fattening, chickens reared for laying/breeding, turkeys reared for breeding and minor poultry species for fattening or raised to the point of lay (BioResource international, Inc.).

Following a request from the European Commission, the EFSA Panel on Additives and Products of Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of the product containing endo‐1,4‐β‐xylanase produced by Komagataella phaffii DSM 33574 (Xylamax) as a zootechnical additive in chickens for fattening, chickens reared for laying/breeding, turkeys for fattening, turkeys reared for breeding and minor poultry species for fattening or raised to the point of lay. The production strain is genetically modified. No viable cells nor recombinant DNA of the production strain were detected in the final product. Therefore, the Panel concluded that the additive does not pose any safety concern regarding the production strain. Based on the no observed adverse effect level identified in a subchronic oral toxicity study in rats, the Panel concluded that Xylamax is safe for all poultry species for fattening or reared to the point of lay. Considering the production strain and the results obtained in the genotoxicity studies, the Panel concluded that the additive is safe for the consumers. The Panel also concluded that Xylamax is not irritant to the skin but should be considered a potential eye irritant and a respiratory sensitiser. No conclusions could be drawn on the potential of the additive to cause skin sensitisation. The use of the product as a feed additive is of no concern for the environment. The FEEDAP Panel concluded that the additive has the potential to be efficacious at 10,000 XU/kg feed in chickens for fattening. This conclusion was extended/extrapolated to chickens reared for laying/breeding, turkeys for fattening, turkeys reared for breeding and minor poultry species for fattening or raised to the point of lay.

Domestic poultry are not susceptible to avian-origin H3N2 subtype canine influenza A virus

At present, avian-origin H3N2 subtype canine influenza virus (H3N2 CIV) is prevalent in East Asian and North American countries. The host tropism of H3N2 CIV to mammals, including mice, guinea pigs, ferrets, and pigs, has been evaluated. However, it has not previously been determined whether avian-origin H3N2 CIV can be transmitted back to birds. In China, ducks, chickens, geese, pigeons, and quails are economically important domestic poultry that are susceptible to numerous subtypes of influenza A virus. These poultry occasionally or frequently come into contact with dogs. In this study, the infectivity of the first- and last-isolated Chinese H3N2 CIV strains in these poultry species was evaluated, and oropharyngeal and cloacal swabs of these animals were negative for virus, as determined by specific pathogen-free (SPF) chicken egg inoculation and real-time RT–qPCR assays. Clinical signs and gross lesions were not observed in any of these species, and seroconversion also did not occur. The results showed that all these avian species were unsusceptible to the first- and last-isolated H3N2 CIVs, indicating unidirectional evolution of the mammalian host tropism of H3N2 CIV.

Molecular detection of avian hepatitis E virus (Orthohepevirus B) in chickens, ducks, geese, and western capercaillies in Poland.

Orthohepevirus B, commonly known as avian hepatitis E virus (aHEV), causes big liver and spleen disease (BLS) or hepatitis-splenomegaly syndrome (HSS) in chickens. BLS is an emerging disease among chicken flocks in several countries around the world. In our previous studies, serology and molecular biology screening revealed that chicken flocks are widely affected by aHEV in Poland. The present study, which was conducted between 2019 and 2020, aimed to investigate the prevalence of aHEV in chicken flocks and other poultry, including ducks, geese, and turkeys. A total of 307 flocks were examined. In addition, 29 samples from captive wild birds (western capercaillies, Tetrao urogallus) were analyzed. In all the investigated poultry species, except turkeys, the nucleic acid sequence covering part of the ORF1 gene of the aHEV genome was detected (34/336 samples, 10.1%). The infection rate was found to be the highest in broiler breeder chicken flocks (14/40 samples; 35%). Phylogenetic analysis of partial ORF1 gene, which encodes helicase, revealed that the obtained sequences belonged to genotypes 2 and 4, while one belonged to genotype 3. Genotype 2 was detected for the first time in domestic geese and ducks, and genotype 4 was detected for the first time in Poland. The study demonstrated the presence of aHEV among the investigated western capercaillies, suggesting that this species is susceptible to aHEV infections and biosecurity is therefore required in western capercaillie breeding facilities.

Immunomodulatory potential of black soldier fly larvae: applications beyond nutrition in animal feeding programs.

Insect-derived ingredients, including whole larvae, protein-rich meal, and oil, have been extensively studied in recent years and shown to be a sustainable source of quality nutrition for virtually all animal species and life stages. In addition to the ability to use these ingredients as a source of essential nutrition, more recent research has demonstrated the potential for the immunomodulatory activity of various components of insect-derived ingredients. For all insects studied, antimicrobial peptides make up a critical part of the insects’ innate immune system and these peptides have antimicrobial efficacy when purified from hemolymph and tested in vitro. From black soldier fly larvae, in particular, lauric acid is a predominant fatty acid deposited into the insect, and lauric acid also has potential antimicrobial activity in vitro and in vivo. Finally, the chitin and chitosan components of the insect exoskeleton may modulate microbial activity in a variety of ways. In companion animals, poultry, and livestock species, insect-derived ingredients have shown the potential to reduce the impact of actual or simulated disease challenge on several parameters of animal health and well-being. This review describes the current state of knowledge of the immunomodulatory potential of insect-derived ingredients.

Comparative assessment of bone collagen recovered from different livestock and poultry species: microstructure, physicochemical characteristics and functional properties

SummaryThis study aimed to recover and characterise livestock and poultry bone collagens (LBCs) from yak (YBC), bovine (BBC), porcine (PBC) and chicken (CBC) sources and perform comparative assessment on their microstructure, physicochemical and functional properties. Amino acid compositions, SDS–PAGE and spectroscopic analysis confirmed that LBCs were intact triple‐helical collagen I of [α1(I)]2α2(I) with some structural differences. Scanning electron microscope (SEM) results showed that LBCs displayed a loose and porous fibrous meshwork. The Td values of SCI, YBC, BBC, PBC and CBC were 42.6, 42.3, 44.6, 41.9 and 42.9 °C, and 5.81, 7.15, 6.28, 6.79 and 5.33 of pI values, respectively. Structural differences also endowed LBCs with dissimilar functional properties, such as water‐holding capacity, foaming and emulsifying. The structure–function correlations analysis revealed the structure–function correlations of LBCs. This study offered a new prospect that the sustainable livestock and poultry bones (LBs) might be valorised as an alternative collagen source and provided useful information for the industrial production and fostered further rational valorisation of LBCs.

Safety and efficacy of the feed additive consisting of 6-phytase (produced by Komagataella phaffii CGMCC 7.19) (Nutrase P) for chickens for fattening, other poultry for fattening or reared for laying and ornamental birds (Nutrex N.V.).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of 6‐phytase produced by a genetically modified strain of Komagataella phaffii (CGMCC 7.19) (Nutrase P) for chickens for fattening, other poultry for fattening or reared for laying and ornamental birds. The additive is available in solid (Nutrase PD 100,000, Nutrase PG 10,000 and Nutrase PTS 10,000) and liquid (Nutrase PL 10,000) forms. In 2020, the FEEDAP Panel issued an opinion on the safety and efficacy of the product and concluded that uncertainties remained on the presence of viable cells and recombinant DNA of the production strain in two of the formulations (Nutrase PL 10,000 and Nutrase PD 100,000). Moreover, the Panel could not conclude on the safety and the efficacy of the additive for the target species at the recommended level of 250 FTU/kg complete feed. The applicant provided supplementary information to address the limitations identified in that assessment and requested to increase the minimum recommended use level to 500 FTU/kg complete feed. No viable cells and recombinant DNA of the production strain were detected in Nutrase PL 10,000 and Nutrase PD 100,000. Therefore, the Panel concluded that the additive, in any formulations, does not pose any safety concern with regard to the production strain. Based on the results of a new tolerance trial, the Panel concluded that Nutrase P is safe for the target species. The additive in any formulation is safe for the consumers and the environment, but should be considered a respiratory sensitiser. Considering the two long‐term trials in chickens for fattening previously evaluated and the new trial submitted, the Panel concluded that the additive is efficacious in chickens for fattening, other poultry species for fattening or reared for laying and ornamental birds at 1,500 FTU/kg complete feed.