Parasitoid longevity, utilization of Homalodisca coagulata (Say) (Hemiptera: Cicadellidae) eggs of diVerent ages, and progeny survival rates were determined in the laboratory for Gonatocerus ashmeadi Girault, Gonatocerus triguttatus Girault, and Gonatocerus fasciatus Girault (Hymenoptera: Mymaridae). Ovipositional behavior and aggression between females were investigated when all three species ...

Tris(1-chloro-2-propyl) phosphate (TCPP) and tris(1,3-dichloro-2-propyl) phosphate (TDCPP) are organic flame retardants detected in the environment and biota for which avian toxicological data are limited. In this study, domestic chicken eggs were injected with TCPP or TDCPP (maximum dose = 51,600 and 45,000ng/g egg, respectively) to determine dose-dependent effects on pipping success, developm...

Several strategies are being developed to minimize nitrogen (N) pollution from poultry waste in areas with high concentrations of commercial poultry operations. This study focus on the effect of feeding reduced protein (CP) diets on laying hens housed under commercial conditions. The experiment was carried out using 144 Hy-Line W-36 hens which were randomly assigned to one of four dietary treat...

The interaction between essential dietary components and changes in tissue nutrient reserves, egg quality and egg composition, were studied from 60 d before and during the spawning of Sparus aurata broodstock. Fish were given isonitrogenous (550 g/kg dry weight) and isolipidic (100 g/kg dry weight) diets, based on protein and lipid extracts of squid meal. Diets differed in the levels of n-6 (10...

The present study was conducted to evaluate the effect of two types of commercially available enzymes (Avizyme ® and Kemzyme ® ) on laying hens performance. A total of 200, forty weeks old, Matrouh laying hens were randomly selected and divided into 4 groups (5 replicate pens of 10 hens each).The first group received unsupplemented basal diet and served as a control group. The second and the th...

The aim of this study was to evaluate the effects of dietary vitamin E on reproductive and productive parameters in Japanese quails. A total number of 240 female and 80 male Japanese quail were divided into five treatments with four replications in a completely randomized design. Experimental diets were zero control, 30, 60, 120 and 240 mg kg-1 of vitamin E. Fertility and total hatch...

Hy-line brown commercial layers (32 weeks old) were used to investigate the effects of GABA (gamma-aminobutyric acid) derived from E. coli strains on productivity, egg quality, and blood profile. In total, 288 birds (1946 ± 0.5 g) were fed four different levels of GABA (0, 25, 50, and 100 ppm), in a basal diet based on corn-soybean meal, for five weeks. Egg production, egg weight, and egg mass ...

The accessory gland proteins (Acps) of the male Drosophila cause changes in the behavior and physiology of female flies. Sex peptide (SP) is one of the Acps that initiates many changes, including an increase in egg production. The data presented here show that SP overexpression in transgenic (G-10) female flies increases egg production when females are kept on a standard and high-calorie diet, ...

Morphology and physiology of fish embryos undergo dramatic changes during their development until the onset of feeding, supplied only by endogenous yolk reserves. For obtaining an insight how these restructuring processes are reflected by body mass related parameters, dry weights (dw), contents of the elements carbon and nitrogen and lipid and protein levels were quantified in different stages ...

Egg size is a widely-studied trait and yet the causes and consequences of variation in this trait remain poorly understood. Egg size varies greatly within many avian species, with the largest egg in a population generally being at least 50% bigger, and sometimes twice as large, as the smallest. Generally, approximately 70% of the variation in egg mass is due to variation between rather than wit...