Abstract The aim of this study was to evaluate and compare the impact genotype storage conditions (temperature time) on microbiological contamination eggshell quality. There were four genotypes laying hens used, Czech Golden Spotted (CGS), Greenleg Partridge (GP), White Leghorn (WL) commercial hybrid (CH) included. After collection, eggs divided equally into five groups according time (0, 14, 2...

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)...

Many passerine birds lay white eggs with reddish brown speckles produced by protoporphyrin pigment. However, the function of these spots is contested. Recently, the sexually selected eggshell coloration (SSEC) hypothesis proposed that eggshell color is a sexually selected signal through which a female advertises her quality (and hence the potential quality of her future young) to her male partn...

Experimental inoculation of commercial laying hens, maintained under controlled conditions, with the S6-strain of Mycoplasma gallisepticum (S6MG) at 10 wk of age has previously been shown to affect the lengths and weights of various portions of the reproductive tract without affecting subsequent performance. Two trials were conducted to compare the effects of S6MG inoculation at 10 wk of age (p...

During the last century, egg production, transport and handling became a specialized industry. Egg quality was for a long time based on visual inspection. Today, the total number of the handled eggs and the rate of grading (up to 180 000 eggs/hour) is such that this visual inspection becomes impossible. This leads to a search for new non invasive devices to measure egg quality parameters. In th...

640 Hy-Line W36 white Leghorn laying hens regarding their ages (28 and 44 weeks) were divided into two 64 groups of 5 bird per cage (16×4 factorial test). 16 experimental diets included a corn soybean meal basal diet containing 50mg/kg Zn and 30mg/kg Mn supplemented with 0-0, 0-30, 0-60, 0-90, 50-0, 50-30, 50-60, 50-90, 100-0, 100-30, 100-60, 100-90, 150-0, 150-30, 150-60 and 150-90 mg/kg of Zn...

Availability of the complete genome sequence as well as high-density SNP genotyping platforms allows genome-wide association studies (GWAS) in chickens. A high-density SNP array containing 57,636 markers was employed herein to identify associated variants underlying egg production and quality traits within two lines of chickens, i.e., White Leghorn and brown-egg dwarf layers. For each individua...

A total of 150 Hy-Line W-36 laying hens at 38 week of age were randomly assigned into 5 dietary treatments and 3 replicates each with 10 birds. Hens were fed diets including: low-selenium diet without selenium supplementation (basal diet), basal diet plus 0.3 ppm Na-selenite, or basal diet plus 0.1, 0.2 and 0.3 ppm Sel-Plex. The hens performance, eggshell quality and egg selenium content were e...

The aim of the study was to evaluate the effect of organic acids and the prebiotic fructans on egg production and eggshell quality when added to the layer diet with different levels of calcium and phosphorus. The experiment was carried out on 168 Bovans Brown hens, allocated to 14 groups of 12 replications. Each hen (replication) was kept in an individual cage 40 cm × 40 cm in size. A 2 × 7 fac...