M. Çabuk, M. Bozkurt, F. Kırkpınar and H. Özkul Department of Poultry Science, Akhisar Vocational School of Celal Bayar University, 45210, Manisa-Turkey Poultry Research Institute, Erbeyli 09600, Aydın-Turkey Department of Animal Science, Agricultural Faculty of Ege University, Bornova 35100, Izmir-Turkey __________________________________________________________________________________________...

Oviparous animals have evolved multiple defenses to prevent microbes from penetrating their eggs and causing embryo mortality. In birds, egg constituents such as lysozyme and antibodies defend against microbial infestation, but eggshell pigments might also impact survival of bacteria. If so, microbes could exert an important selective pressure on the evolution of eggshell coloration. In a previ...

The avian embryo resorbs most of the calcium for bone formation from the calcite eggshell but the exact mechanisms of the resorption are unknown. The present study tested whether this process results in variable fractionation of the oxygen and carbon isotopes in shell calcium carbonate, which could provide a detailed insight into the temporal and spatial use of the eggshell by the developing em...

No single hypothesis is likely to explain the diversity in eggshell coloration and patterning across birds, suggesting that eggshell appearance is most likely to have evolved to fulfill many nonexclusive functions. By controlling for nonindependent phylogenetic associations between related species, we describe this diversity using museum eggshells of 71 British breeding passerine species to exa...

Potentially, pathogenic bacteria are one of the main infective agents against which a battery of chemical and physical barriers has evolved in animals. Among these are the secretions by the exocrine uropygial gland in birds. The antimicrobial properties of uropygial secretions may prevent colonization and growth of microorganisms on feathers, skin and eggshells. However, uropygial gland secreti...

Abnormalities in the histo- and ultrastructure of the amniote eggshell are often related to diverse factors, such as ambient stress during egg formation, pathologies altering the physiology of the egg-laying females, or evolutionarily selected modifications of the eggshell structure that vary the physical properties of the egg, for example increasing its strength so as to avoid fracture during ...

The effects of housing systems on the calcium requirement for eggshell production, eggshell quality and on the breaking strength of the hen’s tibia were evaluated. Unenriched cages (UN) (24 laying hens), enriched cages (EN) (16 laying hens) and floor system (FS) (24 laying hens) were used in this experiment. The eggshell production of laying hens from 19 to 66 weeks of age was higher (P < 0.01)...

The secretion of the eggshell by the follicle cells in the desert locust, Schistocerca gregaria, was studied using the electron microscope. The 3 layers of the eggshell, the vitelline membrane, the endochorion, and the exochorion, are produced in sequence over a short period of about 30-36 h. The follicle cells contain little rough endoplasmic reticulum (RER) and small inconspicuous Golgi bodie...

As a consequence of modernization, industry is spread in the whole world, one of the industries that producing a wastewater as a by-product, iron and steel industry. The result is a huge amount of wastewater that contaminated with iron and steel. Biosorption techniques especially with a natural low cost adsorbent material, namely chicken eggshell is gaining an important goal for treating with a...

Remote regions such as the Antarctic have become increasingly important for investigations into far-reaching anthropogenic impacts on the environment, most recently in regard to the global mercury cycle. Spatial patterns of mercury availability in four regions of the Antarctic Peninsula were investigated using three species of sympatrically breeding Pygoscelis penguins as biomonitors. Eggshells...