Two dwarf brown-egg layer lines, differing in their genotype for the naked neck gene (NA), line L2 (NA*NA/*NA) and line L1 (NA*N/*N), have been selected for 16 generations for increased average clutch length. A control line from the same base population, dwarf and segregating for the NA gene, was maintained by random mating. Genetic parameters were estimated by a multivariate derivative-free re...

the aim of this study was to determine the effect of different dietary levels of walnut leaves powder and vitamin e supplementation on blood antioxidant status, production performance and egg quality characteristics in commercial laying hens. a total number of 216 leghorn hy-line w-36 (70 week old) strain laying hens used the completely randomized design were divided into 6 groups with 3 replic...

This study aimed to characterize production and reproduction performances in Rhode Island Red-White strain chicken developed and maintained at the Central Avian Research Institute, Izatnagar. Three hundred and forty six fertile eggs were set in automated electric incubation and 234 chicks were investigated in three hatches. The performance data was analyzed by least squares analysis of variance...

A study was conducted to evaluate the effects of two laying systems (floor versus cage) on egg production, egg quality, and microbial safety. One hundred and eighty 42 wk old laying hens were separated into two groups of 90 hens each, and housed in laying cages and a floor laying system. Eggs from the hens were collected for 2 weeks, and hen-day egg production, egg quality (whole egg, albumen, ...

ATED females of Drosophila melanogaster commence egg laying on the second or third day following emergence from the puparium (Figure 1). Oviposition rapidly reaches a maximum during days six to ten post eclosion, depending upon the strain, and subsequently declines geometrically at a constant rate, egg production ceasing just prior to the death of the female (ROBERTSON and SANG 1944; GOWEN and ...

A line (E) of turkeys selected long-term (37 generations) for increased egg production was reciprocally crossed with its randombred control population (RBC1) that served as the base population of the E line to study the influence of long-term selection on the development of nonadditive genetic variation for egg production and body weight traits. Heterosis was significant for BW at 8, 16, and 20...

an experiment was conducted to evaluate the effect of dietary crude protein and methionine levels on quality and quantity of egg production. fifteen diets formulated with 3 levels of protein (13, 14 and 15%) and 5 levels of methionine (0.25, 0.28, 0.31, 0.34 and 0.37%) and fed to 420 birds in a 3×5 factorial arrangement. each diet was randomly fed to 4 replicates of 7 birds each and fed for 3 p...

artificial neural networks (ann) have shown to be a powerful tool for system modeling in a wide range of applications. the focus of this study is on neural network applications to data analysis in egg production. an ann model with two hidden layers, trained with a back propagation algorithm, successfully learned the relationship between the input (age of hen) and output (egg production) variabl...

this experiment was conducted to evaluate effects of different levels of mineral and vitamin premixes with wheat and corn base diets on performance and egg traits of laying hens. experiment carried out as 2*5 factorial include wheat and corn base diets and 5 levels of minerals and vitamin premixes (0, 0.25, 0.35, 0.45 and 0.55 percentage) in a completely randomized design with 360 hi-line (w36)...