Super- and low-shedding phenomena have been observed in genetically homogeneous hosts infected by a single bacterial strain. To decipher the mechanisms underlying these phenotypes, we conducted an experiment with chicks infected with Salmonella Enteritidis in a non-sterile isolator, which prevents bacterial transmission between animals while allowing the development of the gut microbiota. We investigated the impact of four commensal bacteria called Mix4, inoculated at hatching, on chicken systemic immune response and intestinal microbiota composition and functions, before and after Salmonella infection. Our results revealed that these phenotypes were not linked to changes in cell invasion capacity of bacteria during infection. Mix4 inoculation had both short- and long-term effects on immune response and microbiota and promoted the low-shedder phenotype. Kinetic analysis revealed that Mix4 activated immune response from day 4, which modified the microbiota on day 6. This change promotes a more fermentative microbiota, using the aromatic compounds degradation pathway, which inhibited Salmonella colonization by day 11 and beyond. In contrast, control animals exhibited a delayed TNF-driven pro-inflammatory response and developed a microbiota using anaerobic respiration, which facilitates Salmonella colonization and growth. This strategy offers promising opportunities to strengthen the barrier effect against Salmonella and possibly other pathogens.

• Klíčová slova
• Salmonella, carrier-state, chicken, excretion, immune response, microbiota, super-shedder, virulence,
• MeSH
• Bacteria * imunologie   klasifikace   genetika   MeSH
• kur domácí imunologie   mikrobiologie   MeSH
• nemoci drůbeže * mikrobiologie   imunologie   prevence a kontrola   MeSH
• Salmonella enteritidis * imunologie   růst a vývoj   fyziologie   MeSH
• salmonelová infekce u zvířat * imunologie   mikrobiologie   prevence a kontrola   MeSH
• střevní mikroflóra * imunologie   MeSH
• symbióza MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

In the present study, the primary action of native cyclodextrins (CDs) on lysozyme protein as binding ligand and secondary as aggregation inhibitor were probed. Thermally induced denaturation using differential scanning calorimetry (DSC) was measured in the presence of native α-, β- and γ-CDs. The denaturation process in CD absence was reversible to 60-80 % at pH≤6 with maximum Tm at pH=4. Denaturation in the presence of native α-CD at pH from 2 to 10, at the least stable and partially reversible conditions in presence of β-CD and γ-CDs at single pH 2 only, was measured. The protein thermal stability decreases in the presence of CDs, with the most evident for β-CD, followed by α-CD and almost no effect for γ-CD. The reversibility in the presence of α-CD was similar to that in its absence. The best protection performance against heat-induced denaturation was found at pH 2 for β-CD. The heat capacity data for α-CD at acidic pH were fitted by the protein-ligand binding model in the whole temperature and ligand concentration ranges studied. The decrease in thermal stability for α-CD at all pH, β- and γ-CD at pH 2 were fitted linearly as a function of ligand concentration. The CD-to-lysozyme binding parameters obtained in this work and from the literature for other CDs are briefly discussed using the concept of cyclodextrin cavity size, charge distribution, solvent accessible surface area and amino acid hydrophobicity.

• Klíčová slova
• Cyclodextrin, Differential scanning calorimetry, Inclusion complex lysozyme binding model,
• MeSH
• cyklodextriny * chemie   farmakologie   MeSH
• denaturace proteinů MeSH
• diferenciální skenovací kalorimetrie MeSH
• koncentrace vodíkových iontů MeSH
• kur domácí MeSH
• muramidasa * chemie   metabolismus   MeSH
• stabilita enzymů účinky léků   MeSH
• teplota * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cyklodextriny * MeSH
• muramidasa * MeSH

Avian leukosis virus (ALV), the prototypical alpharetrovirus, causes tumorigenesis, immunosuppression, and wasting disease in poultry. The ALV genus is classified into ten subgroups, which differ in their host range, cell tropism, and receptor usage. The subgroups A, B, K, and J cause significant economic losses worldwide. The most recently discovered subgroup, ALV-K, which is now widespread in China, has been shown to use the tva cell receptor and share it with ALV-A. However, the specific amino acid residues crucial for ALV-K host cell entry remain unknown. Using precise tva expression and chimeric tva receptors, we further elucidated the significance of the cysteine-rich domain in mediating interactions with both ALV-A and ALV-K. Through a comprehensive analysis of mutated tva receptor variants, we pinpointed tryptophan at position 33 (W33) as a pivotal amino acid residue essential for ALV-K virus binding and entry. Of note is the finding that the substitution of W33 induced resistance to ALV-K while preserving sensitivity to ALV-A. This study not only represents an advance in the understanding of the specificity of the tva receptor for ALV-K, but also offers a biotechnological strategy for the prevention of ALV-K infections in poultry.

• Klíčová slova
• avian leukosis virus, chicken, guineafowl, tva receptor,
• MeSH
• buněčné linie MeSH
• internalizace viru * MeSH
• kur domácí MeSH
• nemoci drůbeže virologie   MeSH
• přichycení viru * MeSH
• ptačí leukóza virologie   MeSH
• ptačí proteiny MeSH
• substituce aminokyselin MeSH
• virové receptory * genetika   metabolismus   chemie   MeSH
• virus ptačí leukózy * fyziologie   genetika   klasifikace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ptačí proteiny MeSH
• Tva receptor MeSH Prohlížeč
• virové receptory * MeSH

The effect of the dietary inclusion of Hermetia illucens larvae meal on the diversity of the methanogenic archaea in the caecum of laying hens (Hy-line Brown) was investigated using molecular methods. A total of 27 hens, selected equally for slaughter from 162 birds which were divided equally into 3 treatment groups including control group C with a diet containing corn-soybean meal and 2 experimental groups, HI25 and HI50, in which 25% and 50% of the soybean meal protein was replaced by the protein from a Hermetia illucens larvae meal, respectively. At 40 weeks of age, the methanogenic community of caecal content of 9 hens per group was analyzed using a 16S rRNA gene clone library. A total of 108 positive clones, 35 from the control group, 44 from the HI25 group and 29 from the HI50 group, were analyzed by Sanger sequencing. Methanomicrobiales, Methanobacteriales and Methanomassiliicoccales were the main orders found in groups C and HI25. Methanomassiliicoccales was absent in the HI50 group, which was dominated by the order Methanobacteriales. At the species level, Methanobrevibacter woesei was the most prevalent species in all three groups regardless of diet. Some species were found exclusively either in the control group (Methanogenic archaeon CH1270) or in the HI25 group (Methanorbis furvi strain Ag1). Methanogenic diversity was significantly lower in the HI50 group compared to the control and HI25 groups and Methanomassiliicoccaceae archaeon DOK was completely suppressed in HI50 group. Our preliminary results indicate that ingestion of Hermetia illucens larvae meal has considerable effect on the methanogenic community, promoting the abundance of Methanobrevibacter woesei and suppressing Methanomassiliicoccaceae archaeon DOK in the caeca of laying hens.

• Klíčová slova
• Egg layers, Insects, Methane,
• MeSH
• Archaea * klasifikace   genetika   MeSH
• cékum * mikrobiologie   MeSH
• dieta veterinární   MeSH
• krmivo pro zvířata analýza   MeSH
• kur domácí * mikrobiologie   MeSH
• larva chemie   MeSH
• methan metabolismus   MeSH
• náhodné rozdělení MeSH
• RNA ribozomální 16S analýza   genetika   MeSH
• střevní mikroflóra * účinky léků   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• methan MeSH
• RNA ribozomální 16S MeSH

This work focuses on profiling N-linked glycans by capillary electrophoresis coupled to mass spectrometry using a novel fluorescent and mass spectrometry (MS) active derivatization tag. The label is based on 2-phenylpyridine bearing tertiary amine and hydrazide functionalities. It provides efficient labeling via hydrazone formation chemistry, promising fluorescence properties, and ionization efficiency in the positive ion MS mode. Electrophoretic analysis in a neutral-coated capillary allowed baseline separation of maltooligosaccharides with limits of detection in nanomolar concentrations. The developed labeling method was successfully applied to the analyses of N-linked glycans released from several glycoproteins such as bovine ribonuclease B, human immunoglobulin G, or chicken albumin.

• Klíčová slova
• Capillary electrophoresis, Glycans, Labeling, Mass spectrometry, Oligosaccharides, Phenylpyridine,
• MeSH
• elektroforéza kapilární metody   MeSH
• hmotnostní spektrometrie * metody   MeSH
• imunoglobulin G chemie   MeSH
• kationty chemie   MeSH
• kur domácí MeSH
• lidé MeSH
• polysacharidy * analýza   chemie   MeSH
• pyridiny * chemie   MeSH
• ribonukleasy chemie   MeSH
• skot MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• imunoglobulin G MeSH
• kationty MeSH
• polysacharidy * MeSH
• pyridiny * MeSH
• ribonuclease B MeSH Prohlížeč
• ribonukleasy MeSH

The circular economy of animal by-products rich in collagen focuses on converting collagen into peptides with a defined molecular weight. Collagen hydrolysates prepared by biotechnological methods from chicken gizzards, deer tendons, and Cyprinus carpio skeletons can be an alternative source of collagen for cosmetic products that traditionally use bovine or porcine collagen hydrolysates. Collagen hydrolysates were characterized by antioxidant activity, surface tension, solution contact angle, and other parameters (dry weight, ash content, and solution clarity). Furthermore, the vibrational characterization of functional groups and their molecular weight was performed using the GPC-RID method. Subsequently, emulsion and gel cosmetic matrices were prepared with 0.5% and 1.5% collagen hydrolysates. Microbiological stability, organoleptic properties, and viscosity were investigated. Verification of the biophysical parameters of the topical formulations was performed in vivo on a group of volunteers by measuring skin hydration and pH and determining trans-epidermal water loss. Fish collagen hydrolysate was the most suitable for cosmetic applications in the parameters investigated. Moreover, it also effectively reduces wrinkles in the periorbital region when used in a gel matrix.

• Klíčová slova
• animal by-products, antimicrobial effect, bioengineering methods, collagen hydrolysate, topical formulation, wrinkles,
• MeSH
• antioxidancia chemie   farmakologie   MeSH
• aplikace lokální MeSH
• emulze chemie   MeSH
• kapři MeSH
• kolagen * chemie   farmakologie   MeSH
• kosmetické přípravky * chemie   farmakologie   MeSH
• kur domácí MeSH
• kůže účinky léků   MeSH
• lidé MeSH
• prasata MeSH
• proteinové hydrolyzáty * chemie   farmakologie   MeSH
• skot MeSH
• stárnutí kůže účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antioxidancia MeSH
• emulze MeSH
• kolagen * MeSH
• kosmetické přípravky * MeSH
• proteinové hydrolyzáty * MeSH

In recent decades, interest in non-traditionally colored eggs has increased. For breeders, this market interest means breeding lines of laying hens that lay eggs of varied colors, such as the blue-green eggshells (Dominant Greenshell) in this study. This study presents the results of genotyping the polymorphism of the O locus responsible for shell coloration and photometric measurement of eggshell color based on the CIELAb system, which was carried out on the unique Czech breeding population Dominant Greenshell. The aim was to use a combination of phenotyping using the CIELab System method and genotyping of the O locus using the end-point PCR approach with the main focus on the accuracy of distinguishing shell color genotypes, streamlining the selection of dominant homozygotes in the O locus, optimizing this technology for the most efficient and cost-effective selection procedure in practical hen breeding. The optometric method was able to reliably distinguish only dominant and recessive phenotypes and eliminate from the population only undesirable recessive homozygotes with a white colored shell. The parameter a* (redness/greenness) from the CIELab color space turned out to be absolutely key for distinguishing dominant and recessive phenotypes. Using the CART methodology, a classification tree built on discriminating optometric characteristics a-blunt was obtained, however, for the group of desirable O/O homozygotes, the selection approach would result in incorrect genotyping of 31% of individuals. Therefore, a combined approach based on rapid and simple elimination of recessive homozygotes using phenotyping (CIELab photometric measurement) and molecular identification of the EAV-HP insertion in the SLCO1B3 gene in dominant phenotypes, regardless of color intensity affected by laying time/order, and allowing reliable elimination, has proven to be the most effective method to distinguish heterozygotes from the breeding population. The combination of optometric and molecular selection methods then leads to more efficient selection, reduction of overall selection costs. This process led to the stabilization of the breeding population within one generation and the achievement of a pure homozygous line with regard to eggshell color.

• Klíčová slova
• CART methodology, Czech blue-shelled breed, L*a*b* color space, PCR marker, SLCO1B3,
• MeSH
• barva * MeSH
• chov * MeSH
• fenotyp * MeSH
• genotyp MeSH
• kur domácí * genetika   fyziologie   MeSH
• pigmentace * genetika   MeSH
• selekce (genetika) MeSH
• vaječná skořápka * fyziologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

This study evaluates the influence of inadequate transport conditions on the microbiological quality of chilled chicken meat packaged in plain and modified atmosphere packaging (MAP). The experiments simulated the temperature increase during sample transport to 8, 11, 14, 17, 20, and 25°C with exposure times of 1, 2, 3, and 4 h. Aerobic plate count (APC), psychrotrophic microorganisms count (PMC), β-D-glucuronidase-positive Escherichia coli, and Salmonella spp. were evaluated immediately after the exposure to the elevated temperature (0 h), 3 h, and 24 h after the return to the temperature of ≤4°C. The upper acceptable limits for APC and PMC were set for each combination of investigated chicken meat and packaging type, taking also the initial bacterial condition into account. Chilled chicken breast samples in plain packaging exceeded the APC limits in 16 cases and PMC limits in 20 cases when exposed to temperatures of >4°C, while only 2 MAP samples exceeded APC limits and 8 samples PMC limits, respectively. In chicken legs, 8 samples in plain packaging exceeded the APC limits and 15 the PMC limits, while 12 samples in MAP exceeded the APC limits and 19 the PMC limits. In 402 samples (31.9%) in which the presence of E. coli was detected, its amount ranged from 1.70 to 3.65 log CFU.g-1. It was more commonly detected in chicken legs (255 of 630; 40.5%) than chicken breasts (147 of 630; 23.3%) but was not related to exposure temperature, exposure time, or time until examination. The presence of Salmonella spp. was not detected in any of the samples. Data acquired in the presented study will be used in the development of software helping the national supervisory authorities in the Czech Republic to evaluate whether inadequate transport of samples to analytical laboratories could have affected the microbiological profile of the sample.

• Klíčová slova
• aerobic plate count, modified atmosphere, plain packaging, psychrotrophic microorganism,
• MeSH
• chlazení MeSH
• Escherichia coli izolace a purifikace   MeSH
• kur domácí * MeSH
• maso * mikrobiologie   MeSH
• nízká teplota MeSH
• obaly potravin * metody   MeSH
• potravinářská mikrobiologie * MeSH
• Salmonella izolace a purifikace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

In this study, we investigated the influence of the inclusion of Tenebrio molitor (TM) larvae meal in the diet on the diversity and structure of the bacterial community in the caecal content of Barbary partridges. A total of 36 partridges, selected randomly for slaughter from 54 animals, were divided equally into three treatment groups, including the control group (C) with a diet containing corn-soybean meal and two experimental groups, in which 25% (TM25) and 50% (TM50) of the soybean meal protein was replaced by the meal from TM larvae. After slaughtering, the bacterial community of the 30 caecal samples (10 samples per each experimental group) was analysed by high-throughput sequencing using the V4-V5 region of the 16 S rRNA gene. Alpha diversity showed a higher diversity richness in the TM50 group. Beta diversity showed statistical dissimilarities among the three groups. Firmicutes was the dominant phylum regardless of the diet, with the predominant families Ruminococcaceae and Lachnospiraceae. Clostridia and Faecalibacterium were decreased in both TM groups, Lachnospiraceae was suppressed in the TM50 group, but still this class, genus and family were abundantly present in all samples. Several potentially beneficial genera, such as Bacillus, Ruminococcaceae UCG-009, Oscillibacter and UC1-2E3 (Lachnospiraceae) were increased in the TM50 group. The results showed a beneficial effect of the T. molitor larvae meal on the caecal microbiota of Barbary partridges, particularly in the TM50 group, which showed an increase in bacterial diversity.

• Klíčová slova
• Tenebrio molitor larvae meal, Caecal microbiota, Partridges,
• MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   MeSH
• biodiverzita MeSH
• cékum * mikrobiologie   MeSH
• dieta MeSH
• Galliformes mikrobiologie   MeSH
• krmivo pro zvířata * MeSH
• larva * mikrobiologie   MeSH
• RNA ribozomální 16S genetika   MeSH
• střevní mikroflóra * MeSH
• Tenebrio * mikrobiologie   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• RNA ribozomální 16S MeSH

In recent years, the chorioallantoic membrane (CAM) has emerged as a crucial component of biocompatibility testing for biomaterials designed for regenerative strategies and tissue engineering applications. This study explores angiogenic potential of an innovative acellular and porous biopolymer scaffold, based on polyhydroxybutyrate and chitosan (PHB/CHIT), using the ex ovo quail CAM assay as an alternative to the conventional chick CAM test. On embryonic day 6 (ED6), we placed the tested biomaterials on the CAM alone or soaked them with various substances, including vascular endothelial growth factor (VEGF-A), saline, or the endogenous angiogenesis inhibitor Angiostatin. After 72 h (ED9), we analyzed blood vessels formation, a sign of ongoing angiogenesis, in the vicinity of the scaffold and within its pores. We employed marker for cell proliferation (PHH3), embryonic endothelium (WGA, SNA), myofibroblasts (α-SMA), and endothelial cells (QH1) for morphological and histochemical analysis. Our findings demonstrated the robust angiogenic potential of the untreated scaffold without additional influence from the angiogenic factor VEGF-A. Furthermore, gene expression analysis revealed an upregulation of pro-angiogenic growth factors, including VEGF-A, ANG-2, and VE-Cadherin after 5 days of implantation, indicative of a pro-angiogenic microenvironment. These results underscore the inherent angiogenic potential of the PHB/CHIT composite. Additionally, monitoring of CAM microvilli growing to the scaffold provides a methodology for investigating the biocompatibility of materials using the ex ovo quail CAM assay as a suitable alternative model compared to the chicken CAM platform. This approach offers a rapid screening method for biomaterials in the field of tissue repair/regeneration and engineering.

• Klíčová slova
• Angiogenesis, Avian animal model, Bone regeneration, Chitosan, Polyhydroxybutyrate,
• MeSH
• biokompatibilní materiály * farmakologie   MeSH
• chitosan * farmakologie   MeSH
• chorioalantoická membrána * účinky léků   MeSH
• fyziologická neovaskularizace účinky léků   MeSH
• křepelky a křepelovití embryologie   MeSH
• testování materiálů MeSH
• tkáňové podpůrné struktury chemie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biokompatibilní materiály * MeSH
• chitosan * MeSH