Ott (1, 2) has shown that desoxypyridoxine (2,4-dimethyl-3-hydroxy5hydroxymethylpyridine) and methoxypyridoxine (2-methyl-3-hydroxy4-methoxymethyl-5-hydroxymethylpyridine), analogues of pyridoxine, act as pyridoxine antagonists in the chick. Because of our interest in the effects of metabolic antagonists on the development of the chick embryo (3), and on the behavior of mouse tumors growing on ...

This study aims to determine the effect of in-ovo injection L-arginine into local chicken eggs on embryo development and chick performance chicken. A total 160 were incubated using semi-automatic incubator with temperature 37-38C relative humidity 55-65%. The injected solution has a concentration 0.5% (m/v). In treatment was divided 4 groups, first without (control), second 0.2 mL (m/v)/egg, th...

During gastrulation in vertebrates, mesenchymal cells at the anterior end of the presomitic mesoderm (PSM) periodically compact, transiently epithelialize and detach from the posterior PSM to form somites. In the prevailing clock-and-wavefront model of somitogenesis, periodic gene expression, particularly of Notch and Wnt, interacts with an FGF8-based thresholding mechanism to determine cell fa...

Spontaneous episodic activity is a general feature of developing neural networks. In the chick spinal cord, the activity comprises episodes of rhythmic discharge (duration 5-90 sec; cycle rate 0.1-2 Hz) that recur every 2-30 min. The activity does not depend on specialized connectivity or intrinsic bursting neurons and is generated by a network of functionally excitatory connections. Here, we d...

Chick-quail chimeras were used to study precursor/progeny relationships of hemopoietic stem cells (SC) that enter the embryonic thymus in waves to give rise sequentially to the TCR-1+, TCR-2+, and TCR-3+ lineages of T cells. The first wave of SC and their progeny were examined by grafting thymus from 9-d chick embryos (E9) into E3 quails. mAbs specific for chick T cell antigens were used to tra...

The chick embryo provides a superb vertebrate model that can be used to dissect developmental questions in a direct way. Its accessibility and robustness following surgical intervention are key experimental strengths. Mica plates were the first barriers used to prevent chick limb bud initiation1. Protocols that use aluminum foil as an impermeable barrier to wing bud or leg bud induction and or ...

Left-right asymmetry is a crucial feature of the vertebrate body plan. While much molecular detail of this patterning pathway has been uncovered, the embryonic mechanisms of the initiation of asymmetry, and their evolutionary conservation among species, are still not understood. A popular recent model based on data from mouse embryos suggests extracellular movement of determinants by ciliary mo...

Unlike mammals, the non-mammalian vertebrate inner ear can regenerate the sensory cells, hair cells, either spontaneously or through induction after hair cell loss, leading to hearing recovery. The mechanisms underlying the regeneration are poorly understood. By microarray analysis on a chick model, we show that chick hair cell regeneration involves the activation of proliferation genes and dow...

objective(s) in this study we investigated the expression of gabaa receptor subunits during brain development. these receptors may change in the embryonic chick forebrain. materials and methodes the expression levels of four types of gabaa receptor gamma subunits (γ1, γ2, γ3 and γ4) were quantified in the embryonic chick forebrain at 32 hr, 3, 7, 14, and 20 days of incubation and day one after ...