Regulation of neuroimmune interactions varies across avian species. Little is presently known about the interplay between periphery and central nervous system (CNS) in parrots, birds sensitive to neuroinflammation. Here we investigated the systemic and CNS responses to dextran sulphate sodium (DSS)- and lipopolysaccharide (LPS)-induced subclinical acute peripheral inflammation in budgerigar (Melopsittacus undulatus). Three experimental treatment groups differing in DSS and LPS stimulation were compared to controls. Individuals treated with DSS showed significant histological intestinal damage. Through quantitative proteomics we described changes in plasma (PL) and cerebrospinal fluid (CSF) composition. In total, we identified 180 proteins in PL and 978 proteins in CSF, with moderate co-structure between the proteomes. Between treatments we detected differences in immune, coagulation and metabolic pathways. Proteomic variation was associated with the levels of pro-inflammatory cytokine mRNA expression in intestine and brain. Our findings shed light on systemic impacts of peripheral low-grade inflammation in birds.

• Klíčová slova
• Cerebrospinal fluid, Dextran sulphate sodium, Endotoxin, Parrot, Plasma, Proteomics,
• MeSH
• centrální nervový systém * metabolismus   imunologie   MeSH
• cytokiny metabolismus   MeSH
• lipopolysacharidy * imunologie   MeSH
• Melopsittacus * imunologie   MeSH
• mozek metabolismus   imunologie   MeSH
• nemoci ptáků imunologie   metabolismus   MeSH
• neuroimunomodulace MeSH
• neurozánětlivé nemoci imunologie   MeSH
• proteom * metabolismus   MeSH
• proteomika metody   MeSH
• ptačí proteiny metabolismus   genetika   MeSH
• síran dextranu * MeSH
• střeva imunologie   MeSH
• zánět * imunologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokiny MeSH
• lipopolysacharidy * MeSH
• proteom * MeSH
• ptačí proteiny MeSH
• síran dextranu * MeSH

During early ontogeny, microbiome affects development of the gastrointestinal tract, immunity, and survival in vertebrates. Bird eggs are thought to be (1) initially sterile (sterile egg hypothesis) and (2) colonized after oviposition through horizontal trans-shell migration, or (3) initially seeded with bacteria by vertical transfer from mother oviduct. To date, however, little empirical data illuminate the contribution of these mechanisms to gut microbiota formation in avian embryos. We investigated microbiome of the egg content (day 0; E0-egg), embryonic gut at day 13 (E13) and female faeces in a free-living passerine, the great tit (Parus major), using a methodologically advanced procedure combining 16S rRNA gene sequencing and microbe-specific qPCR assays. Our metabarcoding revealed that the avian egg is (nearly) sterile, but acquires a slightly richer microbiome during the embryonic development. Of the three potentially pathogenic bacteria targeted by qPCR, only Dietzia was found in E0-egg (yet also in negative controls), E13 gut and female samples, which might indicate possible vertical transfer. Unlike in poultry, we have shown that major bacterial colonization of the gut in passerines does not occur before hatching. We emphasize that protocols that carefully check for environmental contamination are critical in studies with low-bacterial biomass samples.

• Klíčová slova
• egg microbiome, embryo, gastrointestinal tract microbiota, passerine bird, pathogenic bacteria, sterile egg,
• MeSH
• Bacteria genetika   MeSH
• mikrobiota * MeSH
• Passeriformes * mikrobiologie   MeSH
• RNA ribozomální 16S genetika   MeSH
• střevní mikroflóra * MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• RNA ribozomální 16S MeSH