Cuttlefish eggs were exposed to background concentrations of dissolved Ag and Cd, using the radiotracers (110m)Ag and (109)Cd. At different time of the embryonic development (50 days), some eggs were placed in non-contaminating conditions. During the experiment, the uptake and depuration kinetics, and distribution of these metals among the egg compartments (i.e. eggshell, vitellus, peri-vitelli...

Objective. The objective of this study was to investigate changes in pigment, spectral transmission and element content of chicken eggshells with different intensities of pink pigment during the incubation period. We also investigated the effects of the region (small pole, equator and large pole) and pink pigment intensity of the chicken eggshell on the percent transmission of light passing thr...

Although a considerable research effort has gone into studying the dietary pathways of metals to the bodies of laying female birds and their eggs in recent years, no detailed investigations have yet been carried out relating the properties of the biogeochemical environment at large spatial scales to eggshell trace element levels in typical soil-invertebrate feeding birds under natural condition...

The aim of this study was to investigate the effects of different levels of cadmium supplementation (0, 5, 10, 20, 40 and 80 mg/kg) in the diet on performance, egg quality, tibia biomechanical properties and eggshell and bone mineral contents in laying quails. In this 10-week trial, a total of 96 laying quails, aged 21 weeks, were randomly distributed among six experimental groups. Each experim...

A quantitative analysis of NMR proton relaxation in hen egg albumen and yolk is undertaken to research the causes of quality loss during the first few days of storage and to access the feasibility of an on-line NMR sensor of internal egg quality. It is shown that the change in the transverse relaxation in thick egg albumen mainly results from an increase in proton exchange rate resulting from a...

STRNKOVÁ JANA, NEDOMOVÁ ŠÁRKA, KUMBÁR VOJTĚCH, TRNKA JAN. 2016. Tensile Strength of the Eggshell Membranes. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, 64(1): 159–164. The mechanical behaviour of eggshell membranes under tensile loading has been studied. Samples from diff erent bird species (hen, goose and Japanese quail) have been used. Samples were cut out of the m...

One hundred and eighty 28-days-old Arbor Acres broiler birds were utilized in a 28 day experiment to investigate the effect of replacing bone ash with eggshell meal in the diet of broiler birds on their nutrient digestibility and blood parameters. Five experimental diets tagged T1, T2, T3, T4 and T5 were formulated to be isocaloric (2865.53 kcal ME/kg) and isonitrogenous (20% crude protein) suc...

The size and orientation of calcium carbonate crystals influence the structure and strength of the eggshells of chickens. In this study, estimates of heritability were found to be high (0.6) for crystal size and moderate (0.3) for crystal orientation. There was a strong positive correlation (0.65) for crystal size and orientation with the thickness of the shell and, in particular, with the thic...

Eggshell colouration is thought to function as a female-specific secondary sexual trait. While tests of this idea are rapidly accumulating in cavity-nesting birds, some fundamental underlying assumptions remain rarely investigated: namely, can males see eggshell coloration and perceive colour differences between the eggs of different females? We tested these two key assumptions in a natural pop...