Targeted differential photostimulation alters reproductive activities of domestic birds.

Modern poultry production systems use environmentally controlled houses providing only artificial illumination. The role of light in reproduction of poultry depends on light quality (photoperiod, intensity/brightness, and spectrum), which enables us to provide custom-made illumination, targeted for the elevation of reproductive activities. Artificial targeted illumination significantly affects poultry reproduction.

Role of the serotonergic axis in the reproductive failure associated with aging broiler breeder roosters.

Reproductive failure associated with aging is a well-known phenomenon. However, the mechanism by which this failure occurs in broiler breeder roosters is still unclear. A previous study conducted in our laboratory, comparing young and aging broiler breeder roosters, demonstrated an elevation in hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) gene expression accompanied by a deterioration of gonadal axis function.

Age-related changes in gonadal and serotonergic axes of broiler breeder roosters.

Fertility of domestic roosters decreases at ≈ 50 wk of age. In a previous study on aging white leghorn roosters, low fertility was accompanied by low levels of both hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) mRNA expression; however, their role in aging broiler breeder rooster reproduction is still unclear. In this study we compared reproductive activities of young (35-wk-old) and aging (73-wk-old) broiler breeder roosters.

The effect of parachlorophenylalanine and active immunization against vasoactive intestinal peptide on reproductive activities of broiler breeder hens photostimulated with green light.

Photostimulation of retinal photoreceptors appears to inhibit reproductive activity in birds. In the present study, the involvement of serotonin and vasoactive intestinal peptide was investigated in relation to reproductive failure associated with retinal photostimulation. Hens at 23 wk of age were divided into six rooms equipped with individual cages.

The effect of active immunization against vasoactive intestinal peptide (VIP) and inhibin on reproductive performance of aging White Leghorn roosters.

Decreasing fertility in aging domestic roosters is a well-known phenomenon. Aging is manifested by a decrease in plasma testosterone level, testis function, and spermatogenesis, resulting in a low level of fertility. The roles of vasoactive intestinal peptide (VIP) and testicular inhibin in this aging process are not clear.