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Meeting Abstract

P1-115   -   The effect of the egg-shell microbiome on embryo development and hatchling phenotypes in an oviparous lizard Johnson, M/R*; Murphy, K/M; Warner, D/A; Tennessee Technological University, Department of Biology; Auburn University, Department of Biological Sciences; Auburn University, Department of Biological Sciences mreadjohnson@gmail.com

Many animals have mutualistic relationships with bacteria that live on or in their bodies. However, relatively few studies have examined the relationship between bacteria on eggshells and the developing embryo. Due to the permeability of lizard eggshells, microbiota outside the shell can potentially travel through egg contents and affect the embryo in ways that might influence hatchling survival and/or development. I used the brown anole (Anolis sagrei) as a model to examine whether the quantity of microbiota on the eggshell surface can affect embryonic development and offspring fitness. We collected eggs from captive lizards and randomly assigned them to one of four treatments: 1) water submersion (procedural control), 2) bleach submersion to reduce bacterial growth, 3) tryptic soy broth (TSB) submersion to enhance bacterial growth, and 4) no manipulation (control). The eggs were submerged for 30 seconds and were swabbed for culture before and after treatment. We then measured bacterial colony concentrations, embryo heart rate, and egg survival. All hatchlings were measured for size (mass, length), sprint speeds, and survival. Results reveal that bleach-treated eggs had low counts of microbial growth and eggs treated with TSB had high microbial growth. However, preliminary analyses reveal that eggshell treatment had little to no phenotypic effect on offspring. These results will evoke questions for future studies examining the functional significance of eggshell microbiota in other oviparous species.