<p>The development of the avian embryo is dependent of heat provisioning from the parents. To increase the heat transfer to a cooled egg the Zebra finch females develop a brood patch. Mild cooling generally constricts the blood vessels but the Arterio-venous anastomoses (AVA) in the brood patch in birds dilate. This is called cold-induced vasodilation CIVD. The Zebra finches were anesthetized with isoflurane and the brood patch was stimulated with a cooling probe set at 20-21 °C. Differences in the vascular changes to cooling in broody and non- broody birds were studied by comparing males and broody females. The brood patch skin was cooled, but no cold-induced vasodilation (CIVD) was documented for the males or the broody females. Isoflurane anesthesia depresses the sympathetic nervous system activity and the results support that the mechanism for CIVD in the brood patch of Zebra finches depends on a neural pathway, but does not exclude a local non-neural mechanism.</p>

The development of the avian embryo is dependent of heat provisioning from the parents. To increase the heat transfer to a cooled egg the Zebra finch females develop a brood patch. Mild cooling generally constricts the blood vessels but the Arterio-venous anastomoses (AVA) in the brood patch in birds dilate. This is called cold-induced vasodilation CIVD. The Zebra finches were anesthetized with isoflurane and the brood patch was stimulated with a cooling probe set at 20-21 °C. Differences in the vascular changes to cooling in broody and non- broody birds were studied by comparing males and broody females. The brood patch skin was cooled, but no cold-induced vasodilation (CIVD) was documented for the males or the broody females. Isoflurane anesthesia depresses the sympathetic nervous system activity and the results support that the mechanism for CIVD in the brood patch of Zebra finches depends on a neural pathway, but does not exclude a local non-neural mechanism.

<p> </p><p>The regulation of egg temperature requires the transfer of heat from the brood patch. Thus, the brood patch needs the presence of thermo receptors as well as an appropriate vasomotor response. During the incubation an exact detection of the egg’s temperature is essential. So, in this study we attempted to detect the presence and regulation of the expressionof  thermoTRP channels (thermo Transient Receptor Potential channels) (TRPV1, TRPV3, TRPV4, TRPM8 and TRPA1) during egg incubation. Six incubating Jungle fowl hens, and five non incubating jungle fowl hens and one jungle fowl cock were used as main samples and controls. Total RNA was extracted from liver, kidney, heart, blood, White Blood Cell, Dorsal Root Ganglion and skin. The samples from the skin were taken from the brood patch and inter scapular region. PCR investigation showed that different thermo TRP channels were expressed in different tissues. TRPV1, V3, V4 and M8 mRNA were detected in the skin of brood patch. However, V1 and V3 expression in the brood patch skin did not differ between broody and non broody hens. In conclusion, although considerable morphological changes in the skin of brood patch could be seen, the expression of TRPV1 and V3 channels did not change significantly, but this cannot exclude the alteration in the expression of TRP channels in different stages of broodiness or specific parts of skin like AVAs (Arteriovenous anastomosis) which will be the subject for more studies.</p>

The regulation of egg temperature requires the transfer of heat from the brood patch. Thus, the brood patch needs the presence of thermo receptors as well as an appropriate vasomotor response. During the incubation an exact detection of the egg’s temperature is essential. So, in this study we attempted to detect the presence and regulation of the expressionof  thermoTRP channels (thermo Transient Receptor Potential channels) (TRPV1, TRPV3, TRPV4, TRPM8 and TRPA1) during egg incubation. Six incubating Jungle fowl hens, and five non incubating jungle fowl hens and one jungle fowl cock were used as main samples and controls. Total RNA was extracted from liver, kidney, heart, blood, White Blood Cell, Dorsal Root Ganglion and skin. The samples from the skin were taken from the brood patch and inter scapular region. PCR investigation showed that different thermo TRP channels were expressed in different tissues. TRPV1, V3, V4 and M8 mRNA were detected in the skin of brood patch. However, V1 and V3 expression in the brood patch skin did not differ between broody and non broody hens. In conclusion, although considerable morphological changes in the skin of brood patch could be seen, the expression of TRPV1 and V3 channels did not change significantly, but this cannot exclude the alteration in the expression of TRP channels in different stages of broodiness or specific parts of skin like AVAs (Arteriovenous anastomosis) which will be the subject for more studies.