this experiment was conducted to evaluate the effects of using rice bran, combo multi-enzyme and probiotic (protexin) in diet on performance, egg traits, biochemical parameters and blood cells of commercial laying hens. this experiment carried out using 384 hi-line (w36) laying hens in a completely randomized design as factorial (2×2×2) arrangement with two levels of rice bran (0 and 10%), two ...

The trade-off between reproductive investment and migration should be an important factor shaping the evolution of life-history traits among populations following their radiation into habitats with different migratory costs and benefits. An experimentally induced difference in migratory rigor for families of chinook salmon (Oncorhynchus tshawytscha), of approximately 86 km and 413 m elevation, ...

Aplysia egg laying is a complex behavior requiring synchronized activity in many organs. Aspects of the behavior are synchronized via the direct effects of peptide bag cell neurohormones and via stimuli arising during the behavior. Stimuli synchronizing egg laying were examined by treating A. fasciata with a nitric oxide (NO) donor. NO elicited normal appetitive and consummatory behaviors leadi...

The presence of a mixture of progestogens at ng/L concentration levels in surface waters is a worldwide problem. Only a few studies explore the effect of progestogen treatment in a mixture as opposed to individual chemicals to shed light on how non-target species respond to these contaminants. In the present study, we used an invertebrate model species, Lymnaea stagnalis, exposed to a mixture o...

Movement uses resources that may otherwise be allocated to somatic maintenance or reproduction. How does increased energy expenditure affect resource allocation? Using the butterfly Speyeria mormonia, we tested whether experimentally increased flight affects fecundity, lifespan or flight capacity. We measured body mass (storage), resting metabolic rate and lifespan (repair and maintenance), fli...

The aim of this study was to recognize the effects of dietary hempseed (HS) and hempseed oil (HO) on performance, egg quality and blood parameters of laying hens. A total of 320 Hy-line 55-weeks laying hens were randomly allotted to eight dietary treatments with five replicates (8 birds each). The experimental treatments were offered as a completely randomized design as follow: control group (n...

-TO better understand the effects of egg mass and position in the laying sequence on reproductive success of Canada Geese (Brunta canadensis), I determined the fate of eggs, marked embryos near hatching, and recaptured goslings near fledging. Hatching success did not correlate with egg mass and position in the laying sequence. The probability of recapturing marked goslings near fledging was not...

Seven separate experiments were conducted with Hy-Line W-36 hens to determine the ideal ratio of Arg, Ile, Met, Met+Cys, Thr, Trp, and Val relative to Lys for maximal egg mass. The experiments were conducted simultaneously and were each designed as a randomized complete block design with 60 experimental units (each consisting of 1 cage with 2 hens) and 5 dietary treatments. The 35 assay diets w...

this experiment was conducted to evaluation the effects of different levels of untreated and treated green grape leaf with urea on performance, egg quality traits and blood parameters of laying hens. in this experiment 192 hy-line (w-36) laying hens, 35 to 46 wk of age were divided in to 4 treatments with 4 replicates (12 birds per replicate) in a completely randomized design experiment. the tr...

this experiment was designed to evaluate the effects of different sources of calcium at different rates and cholecalciferol(vitamin d3) on the performance and egg quality of hy-line w-36 laying hens. in this study a total of 648 hens were managed in a completely randomized design using a factorial arrangement of 3 × 3 × 2 treatments, with three calcium sources (oyster shell, os; ground limeston...