ProventriculusStomach, AvianFlea InfestationsSiphonapteraDigestive SystemCrop, AvianGizzardTemperaturePoultry DiseasesCtenocephalidesBody TemperatureChickensChick EmbryoDrosophila ProteinsEctoparasitic InfestationsHot TemperatureXenopsyllaDrosophilaCold TemperaturePlagueGene Expression Regulation, DevelopmentalRickettsia felis