Transmission of specific immunoglobulins from mothers to their offspring via the egg is a common phenomenon in egg-laying vertebrates but the occurrence of this phenomenon in reptiles, especially in colubrid snakes, has not been proven until recently. Thus, the essential biochemical characteristics of antibodies deposited in eggs of Elaphe guttata (Colubridae, Serpentes) were studied after isol...

one-hundred-sixty-eight 28-wk-old hy-line layers (w-36) were used to evaluate the effect of different levels of linseed (ls) and safflower seed (ss) on antibody titter, blood and yolk cholesterol, yolk fatty acid content and the ratio of omega-6/ omega-3. hens were randomly assaigned in a compeletly randomised design each 3 replicates of 8 hens. they were fed diets contained 0, 4, 7 and 10% ls ...

Despite the strong interest in hormone-mediated maternal effects two key questions concerning their mechanisms are as yet unanswered: First, whether the deposition of hormones in the egg yolk is coupled with the levels of these hormones in the maternal circulation, and second, whether epigenetic changes as induced by embryonic exposure to maternal yolk hormones impinge on yolk hormone depositio...

The external dimensions, weight and contents (yolk, albumen, shell) of Double Yolked (DY) and Single Yolked (SY) eggs of the duck (Anas platyrhynchos domesticus) were measured and compared. The yolks in DY eggs did not differ in weight (p = 0.144), although each double yolk was significantly lighter than the yolk of a SY egg (p<0.001). DY albumen weight was below that expected of a SY egg of co...

The murine yolk sac, being the first site of embryonic blood cell production, has long been theorized to contain the migrating hematopoietic stem cells (HSC) that seed the liver and initiate hematopoiesis on day 10.0 postcoitus (pc). However, it remains controversial whether yolk sac cells isolated before day 11.0 pc possess any long-term repopulating HSC activity upon transplantation into adul...

Refrigeration to limit bacterial multiplication is a critical aspect of efforts to control the transmission of Salmonella enterica serovar Enteritidis (SE) to consumers of contaminated eggs. Although the nutrient-rich yolk interior is an uncommon location for SE contamination in freshly laid, naturally contaminated eggs, migration across the vitelline membrane could lead to rapid bacterial mult...

The present studies were performed to further characterize a mouse yolk sac protein which is similar or identical to the vitamin D-dependent intestinal calcium-binding protein (CaBP). Yolk sac protein and purified rat intestinal CaBP displayed full identity upon immunodiffusion (Ouchterlony) using antiserum to the rat intestinal CaBP. Immunoreactive CaBP in yolk sac homogenates eluted from gel ...

A structural analysis of the differential proteolysis of vitellogenin (Vtg)-derived yolk proteins in the maturing oocytes of a marine teleost that spawns very large pelagic eggs is presented. Two full-length hepatic cDNAs (hhvtgAa and hhvtgAb) encoding paralogous vitellogenins (HhvtgAa and HhvtgAb) were cloned from nonestrogenized Atlantic halibut, and the N-termini of their subdomain structure...