The invariant chain (Ii) plays an important role as a chaperone for MHC II maturation and facilitates antigen presentation in vertebrates. We cloned, characterized and made a homology analysis of healthy adult muscovy duck Ii (MDIi), from a poultry farm in the suburban district of Hefei city in China, by rapid amplification of cDNA ends (RACE)-PCR and by measuring expression of the MDIi ge...

In a series of polybrominated biphenyl (PBB) feeding trials in White Leghorn cockerel chicks, the effects of PBB on various physiological parameters and organ weights were determined. These measurements included: growth, thyroid function, ECG, cardiac output, blood pressure, hematocrit, erythropoietin levels, and spleen, bursa of Fabricius, thyroid, testes, comb, liver weights. In addition, tis...

Expression of growth hormone (GH) and GH receptor (GHR) genes in the bursa of Fabricius of chickens suggests that it is an autocrine/paracrine site of GH production and action. The cellular localization of GH and GH mRNA within the bursa was the focus of this study. GH mRNA was expressed mainly in the cortex, comprised of lymphocyte progenitor cells, but was lacking in the medulla where lymphoc...

Parasitism can negatively affect learning and cognition, setting the scene for coevolution between brain and immunity. Greater susceptibility to parasitism by males may impair their cognitive ability, and relatively greater male investment in immunity could compensate for greater susceptibility to parasites, in particular when males have a relatively large brain. We analysed covariation between...

We have applied polymerase-chain-reaction-directed immunoglobulin gene analysis to study the embryonic differentiation of chicken B cells. Immunoglobulin light chain DNA segments in the rearranged configuration were amplified from cells of the intraembryonic mesenchyme as early as day 7 of incubation. We showed by sequencing that the rearranged variable region genes in these early B-cell progen...

Antibody diversification in the bursa of Fabricius occurs by gene conversion: pseudogene-derived sequences replace homologous sequences in rearranged immunoglobulin genes. Bursal cells expressing a truncated immunoglobulin mu heavy chain, introduced by retroviral gene transfer, bypass normal requirements for endogenous surface immunoglobulin expression. Immunoglobulin light chain rearrangements...

Environmental particles enter the chicken via several routes. Entry via the respiratory and cloacal routes likely activates immune responses. We studied the localization of simultaneous intratracheally and cloacally applied beads of 2 sizes in the chicken body in time, and when possible, semiquantified the amount of beads. Ten broiler hens, 3.5 wk of age, received 1.25 × 10(9) 1.0-µm beads and ...

In vitro binding efficacy of esterified glucomannan (E-GM) (0.1%) on aflatoxin B1 (AF) (300 ppb), ochratoxin A (OA) (2 ppm) and T-2 toxin (T-2) (3 ppm), when present alone or in combination, was evaluated in toxin-contaminated feed at pH 4.5 and 6.5. Esterified glucomannan showed significantly (p<0.01) higher binding with AF (81.6%), whereas those recorded with T-2 (27.8%) and OA (25.6%) were m...

BACKGROUND This study aimed at investigating a potential effect caused by coccidia on the immune response to vaccine- and very virulent infectious bursal disease virus (vvIBDV) in SPF chickens. METHODS Two groups of three weeks old SPF chickens were vaccinated prior to inoculation with coccidia and challenge with virulent IBDV, all within a period of eight days. Two control groups were simila...

DNA methylation is an important epigenetic modification in eukaryotes, which plays a significant role in regulating gene expression. When the host is invaded by the influenza virus, gene expression is regulated via changes in DNA methylation levels or patterns, leading to the activation or suppression of relevant signaling pathways or networks, triggering a series of immune responses against vi...