the experiment was carried out in poultry experimental station belonging to nrc, cairo, egypt. a total of 120 fayoumi layers, 45 weeks old, were randomly divided into four equal groups. each group included three replicates (10 hens in each). the first group was fed the control diet containing 3.3% gram ca, whereas, the other three received diets containing 2.8, 2.6 and 2.4% gram ca, respectivel...

Five treatments were used to exclude naturally occurring predators and parasitoids, based on body size and flight ability, to assess their effect on Ostrinia nubilalis (Hübner) populations on corn plaits. Two initial O. nubilalis egg densities (one egg mass and three egg masses per plant) were assigned to each treatment. Egg predation was higher in uncaged treatments than in caged treatments. F...

in this experiment, the influence of prebiotic and probiotic supplementation in the broiler breeder diets on body weight, mortality, feed intake, egg production, hatchability and humoral immunity response was investigated. a total number of 13140 female and 1260 male breeders (cobb 500) with 26 wks of age were allocated to three treatments with six replicates (800 birds each replicate). breeder...

A theoretical model of the winter survival dynamics of Meloidagyne spp. was developed by considering the roles of egg hatching and juvenile mortality and the initial populations of eggs and juveniles at the onset of winter. Two distinct patterns of juvenile dynamics appear which depend upon the numerical values of the model parameters. The model predicts whether eggs or juveniles are the major ...

Sexual size dimorphism varies substantially among populations and species but we have little understanding of the sources of selection generating this variation. We used path analysis to study how oviposition host affects selection on body size in a seed-feeding beetle (Stator limbatus) in which males contribute large ejaculates (nuptial gifts) to females. Females use nutrients in these ejacula...

Barriers to gene flow can result in populations evolving into separate species, and understanding how these barriers evolve is a key step the process of speciation. This study investigates major barrier flow, mortality during development, two parasitoid wasp Nasonia vitripennis Walker N. giraulti Darling. Previous work has demonstrated high haploid hybrid males species shown potential rescue fr...