Age-related changes of yolk precursor formation in the liver of laying hens.

A rapid decline in egg production of laying hens begins after 480 d of age. Such a rapid decrease results predominantly from the ovarian aging, accompanied by endocrine changes, decreased yolk synthesis and accumulation, and the reduction in follicles selected into the preovulatory hierarchy. In this study, hens at 90, 150, 280, and 580 d old (D90, D150, D280, and D580, respectively) were compared for yolk precursor formation in the liver to elucidate effects of aging on laying performance.

[Dexamethasone acetate microemulsions: formulation and effect on skin permeability].

The present project was designed to optimize the microemulsion (ME) formulation of oil in water (O/W) for dexamethasone acetate (DA), and examine its impact on DA percutaneous permeation. The saturated solubility of DA in different oils, surfactants and co-surfactants was tested. The ratio of surfactant to co-surfactant was selected by constructing pseudo three phase diagrams to investigate the maximal microemulsion area.

Follicle-stimulating hormone promotes proliferation of cultured chicken ovarian germ cells through protein kinases A and C activation.

The study was conducted to investigate the effects of follicle-stimulating hormone (FSH) on embryonic chicken ovarian germ cell proliferation and its possible involvements of protein kinases A (PKA) and C (PKC) pathways. Ovarian cells were treated with FSH alone or in the presence of forskolin (FRSK), PKA inhibitor (H(89)), PKC activator (PMA) or inhibitor (H(7)). The germ cell number was counted from micropictures.

Attenuating effect of daidzein on polychlorinated biphenyls-induced oxidative toxicity in mouse testicular cells.

The attenuating effect of daidzein (DAI) on oxidative toxicity induced by Aroclor 1254 (A1254) was investigated in mouse testicular cells. Cells were exposed to A1254 alone or with DAI. The oxidative damage was estimated by measuring malondialdehyde (MDA) formation, superoxide dismutase (SOD) activity and glutathione (GSH) content.