Hormonal influence on salivary glands of chimney swift (Chaetura pelagica) in organ culture

Abstract

Salivary glands from chimney swifts taken at intervals during the reproductive season were maintained in organ culture in a chemically defined medium supplemented with insulin, glucagon, prolactin, corticosterone, testosterone and crude pituitary extract in various combinations. Insulin and corticosterone or glucagon promoted survival of the tissues in vitro and insulin plus corticosterone or glucagon promoted secretory activity. Prolactin, crude pituitary extract or testosterone did not promote secretion. Essenially one hundred percent of the cultured explanta survived when incubated at 37°C. However, at 44°C a large proportion of the explants failed to survive except in the presence of insulin plus corticosterone or glucagon. Prolactin did not promote survival at high incubation temperature. Hormones primarily concerned with carbohydrate metabolism appear to play an important role in in vitro survival and secretion. The appearance of secretion in vitro may be owing to the support of secretory processes initiated in vivo prior to the culture period.

Avian commensals in Colonial America: when did Chaetura pelagica become the chimney swift?

“…The swift nested in hollow trees, or perhaps in caves, in most of eastern North America south of the boreal forest in pre-Colonial America (Wilson, 1812;Tyler, 1940;Cink and Collins, 2002). Invariably placed in a shaded site, well protected from the elements, the swift's nest is constructed of small twigs cemented together with saliva from seasonally enlarged sublingual glands (Johnston, 1958;Barnawell, 1968). Invariably placed in a shaded site, well protected from the elements, the swift's nest is constructed of small twigs cemented together with saliva from seasonally enlarged sublingual glands (Johnston, 1958;Barnawell, 1968).…”

Avian commensals in Colonial America: when did Chaetura pelagica become the chimney swift?

“…Today, it nests almost exclusively in man-made structures such as chimneys, wells, silos, interiors of abandoned cabins and houses, porches and barns (Amadon, 1936;Tyler, 1940;Dexter, 1952;Fischer, 1958). Invariably placed in a shaded site, well protected from the elements, the swift's nest is constructed of small twigs cemented together with saliva from seasonally enlarged sublingual glands (Johnston, 1958;Barnawell, 1968). The shift to man-made structures has been so extensive that reports of swifts nesting in natural sites are now regarded as noteworthy events.…”