Experimental venue affects growth rate and body shape in the sheepshead minnow
Poster Number
23
Format
Poster Presentation
Faculty Mentor Name
Santiago Salinas
Faculty Mentor Department
Biological Sciences
Abstract/Artist Statement
When designing experiments, the choice of venue or housing is typically not given much thought (at least in ichthyological research). Anecdotal accounts, however, suggest the choice of aquarium or container size could influence the phenotype of the studied individuals. To empirically assess whether this is something to be concerned about, we tested how cage size influenced growth and body shape of the sheepshead minnow, Cyprinodon variegatus, a common east coast estuarine fish. We grew individuals over the course of 8 weeks in 3 cylindrical chamber sizes (diameter small=50 mm, medium=85 mm, large=135 mm; n=15 per treatment). We photographed and digitally measured fish weekly for length estimation and at the end of the experiment for geometric morphometrics analysis. Chamber size influenced both growth rate and body shape. Individuals grown in the medium and large containers had similar growth rates, while those in the small chambers had significantly slower growth rates and consequently achieved a smaller final size (~10% smaller). Fish shape differed across all treatments, as individuals grown in large containers featured more prominent humps than the others, fish grown in medium containers were deeper bodied, and small-chamber-grown fish had a narrow body and subdued hump. These results confirmed the importance of rearing venue to life history and morphological traits. We must therefore take proper precautions when undertaking metaanalyses and carefully design hatcheries to avoid undesired phenotypes.
Location
DeRosa University Center, Ballroom
Start Date
25-4-2015 10:00 AM
End Date
25-4-2015 12:00 PM
Experimental venue affects growth rate and body shape in the sheepshead minnow
DeRosa University Center, Ballroom
When designing experiments, the choice of venue or housing is typically not given much thought (at least in ichthyological research). Anecdotal accounts, however, suggest the choice of aquarium or container size could influence the phenotype of the studied individuals. To empirically assess whether this is something to be concerned about, we tested how cage size influenced growth and body shape of the sheepshead minnow, Cyprinodon variegatus, a common east coast estuarine fish. We grew individuals over the course of 8 weeks in 3 cylindrical chamber sizes (diameter small=50 mm, medium=85 mm, large=135 mm; n=15 per treatment). We photographed and digitally measured fish weekly for length estimation and at the end of the experiment for geometric morphometrics analysis. Chamber size influenced both growth rate and body shape. Individuals grown in the medium and large containers had similar growth rates, while those in the small chambers had significantly slower growth rates and consequently achieved a smaller final size (~10% smaller). Fish shape differed across all treatments, as individuals grown in large containers featured more prominent humps than the others, fish grown in medium containers were deeper bodied, and small-chamber-grown fish had a narrow body and subdued hump. These results confirmed the importance of rearing venue to life history and morphological traits. We must therefore take proper precautions when undertaking metaanalyses and carefully design hatcheries to avoid undesired phenotypes.