egg production is lowered, with the eggshells becoming pro gressively thinner. The serum calcium of the hen falls and there is a depletion of the calcium and phosphorus contents of the bones. Nevertheless, according to Branion, the percentage composition of the shell remains constant, showing that, as in bone formation, if the mineral is deposited, it is laid down in the normal proportion. Deob...

Environmental contaminants may have adverse effects on avian reproduction and may be contributing to declines of avian species nesting along the southern California Coast. Examples of impaired reproduction caused by organochlorine pesticides, PCBs, and elements such as mercury (Hg) and selenium (Se) include delayed ovulation, reduced egg production, defective eggshells, decreased hatchability, ...

In this study, wild hatched eggshells were collected from the nests of threatened Wattled Crane and South Ground-Hornbill in an attempt to determine their total Hg concentrations. A total of fourteen eggshell samples from both bird species were collected from different study areas in the Mpumlanga and KwaZulu-Natal Provinces of South Africa. The eggshells were acid digested under reflux and the...

Eggshell membrane is a kind of cheap, abundant resources with great potential utilization value. A variety active ingredients in it can be used as raw materials for medicine, light industry and other industries. At present, soluble protein, collagen, keratin, sialic acid, hyaluronic acid antimicrobial protein have been successfully extracted from eggshell exploited various fields. This study ai...

Microbial communities present on eggshell surfaces of wild birds are weakly studied, especially their influence on embryo infection and, thus, egg viability. Bacterial density of wild bird eggshells is very low, and most DNA extraction protocols are frequently unsuccessful. We have efficiently adapted a chelex-based DNA isolation method for 16S ribosomal gene amplification from the total commun...

Fig 7. Scanning Electron Micrographs ofMegaloolithus jabulpurensis (VPL/CCE—5C) eggshells. A, Fan shaped spherolith (SP) and pore canal (PC). B, Spongy layer of the spherolith magnified showing arcuate accretion lines and various fracture patterns. C, Spongy layer further magnified to show the typical “Herring-Bone” Pattern. D, Inner eggshell surface showing mamillae with resorption crater (RC)...

Eggshells represent an important part of the fossil record Titanosauria (Dinosauria – Neosauropoda) and their stable isotope compositions are valuable palaeoenvironmental proxies. A new set conventional (δ18O δ13C) clumped (Δ47) titanosaurian eggshells is presented, together with that a bone single associated tooth, sampled in three Late Cretaceous nesting sites from La Rioja Province, NW Argen...