Phospholipases are associated with virulence in bacterial diseases. Vibrio cholerae produces a phospholipase (lecithinase), with enzyme production visualized as a zone of clearing around colonies plated on egg yolk agar. The role of phospholipase in gut colonization or disease pathogenesis is unknown. We used the egg yolk agar assay to clone and characterize a gene encoding a phospholipase from...

the present study was conducted to estimate correlations among performance and egg quality traits in iranian native fowl. data were collected from 21,679 birdsat the isfahan native fowl breeding center to derive genetic parameters for performance traits and egg quality traits were measured on eggs of 1,020 birds. genetic correlations of performance and egg quality traits were estimated with a b...

Two experiments were conducted to evaluate effects of strain [five in Experiment (Exp.) 1 and six in Exp. 2)] and age (29, 47, and 57 wk in Exp. 1 and 29, 41, and 52 wk in Exp. 2) of commercial broiler breeders on incubation time and chick weight. Highly significant differences in egg weight were found among strains in both Exp. After adjusting for effects of egg weight, significant effects of ...

this present study was conducted to evaluate the effects of dietary inclusion of 4, 8 and 12 g kg-1 phytogenic feed additives mixture on performance, egg quality, ovary parameters, serum biochemical parameters and yolk trimethylamine level in laying hens. the results of experiment have shown that egg weight was increased by supplementation of 12 g kg-1 feed additive whereas egg production, feed...

A yolk protein enzyme-linked immunosorbent assay (YP-ELISA) was developed for the predator Orius insidiosus (Say). The YP-ELISA is intended to assess reproductive response to dietary and other rearing conditions, and to assist in quality control and diet development for mass rearing. Hybridomas and monoclonal antibodies were produced against homogenates of eggs dissected from females. Hybridoma...

Sodium bentonite can bind to dietary pigment and decreases yolk color scale. Sodium bentonite is one of the main parts of Formycine® Gold, the effect of different levels of Formycine® Gold and dietary pigment on egg quality, egg yolk color and performance criteria of laying hens from 26 to 34 week of age were studied. One hundred ninety two Hy-Line hens were divided into 24 groups of 8 birds ea...

This study investigated the impact of different levels dietary energy and crude protein on productive performance, egg quality, reproductive parameters in Rajasri breeder birds during a 12-week period between 25 to 36 weeks age. A total 648 were divided into nine treatments, each with eight replicates, following 3 × factorial arrangement three metabolizable (2400, 2500, 2600 kcal ME/kg) (14, 15...

The plasma of laying hens contains a specific biotin-binding protein that appears to be identical with an egg-yolk biotin-binding protein. Both proteins are saturated with biotin and require elevated temperatures to effect the exchange of [14C]biotin for the protein-bound vitamin. The heat-exchange curve in each case is the same and differs sharply from that of avidin, the egg-white biotin-bind...

The presence of phosphorus-containing protein in the yolk of the hen egg was already recognized in 1900 (1). Since then, the egg yolk phosphoproteins received attention in several laboratories (cf. (2)). The first detailed study of the most highly phosphorylated fraction of yolk phosphoprotein, phosvitin, was reported by Mecham and Olcott (3) in 1949. They isolated a product containing 10% phos...

Two breeds of chickens were used to develop reference family and detect QTLs affecting egg quality traits: cocks of a native Polish breed Green-Legged Partidgenous (GlP) and hens of Rhode Island Red (RIR). During the first 100 days of the laying period, the GlP hens lay about 40 eggs weighting on average 50 g, whilst the RIR flock laid 83 eggs with a mean weight of 60 g. QTL analysis of egg qua...