Project Number: 8030-31000-005-17-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jul 1, 2020
End Date: Jun 30, 2022
The first objective is to integrate laboratory disease challenge protocols to evaluate Dermo resistance in family-based Eastern oyster breeding programs. The cooperator will help in obtaining selectively bred lines of oysters and in evaluating their growth and survival, and work with the Agricultural Research Service (ARS) to provide animals from the Gulf of Mexico coastal region as requested. The second objective is to validate the performance of selectively-bred lines of diploid, triploid and tetraploid oysters across a range of production environments and aquaculture practices. The cooperator will evaluate growth, survival and other performance metrics associated with each of these lines, paying particular attention to performance in warmer waters. The third objective is to test effects of multiple stressors on oyster aquaculture production to enhance understanding of genetic improvement efforts targeting the Eastern oyster.
Two extant lines of tetraploids, Alabama and Florida, and a commercially available diploid line will be used to establish a breeding program. Furthermore, a novel regional line will be established, using broodstock from across the Gulf of Mexico coastal region. We will monitor comparative field performance of progeny paying particular attention to warm-water growth, spring/summer mortality and tolerance/resistance to Haplosporidium nelson and other oyster diseases. Working in an experimental farm setting, the effects of various culture methods (e.g., stocking density, routine grading, etc.), will be tested to evaluate performance of these lines in commercial settings. To complement field performance, a variety of physiological responses will be assessed in the laboratory to better explain the mechanisms of any differences observed. In addition, we will characterize performance with respect to detailed oceanographic data. These studies will provide valuable information about differences in line performance and allow growers to make better informed decisions for their farms. In addition, given the high degrees of variation in environmental conditions and the expected increase in that variation in the coming decades, field and laboratory studies will be conducted to test the effects of multiple stressors upon oyster aquaculture. In particular, the occurrence of sporadic but devastating spring/summer mortalities, particularly in triploid oysters, has led to substantial interest in understanding the additive effects of multiple stressors on the Eastern oyster. Methods will include field testing of different lines with extensive environmental monitoring, as well as controlled, manipulative studies in the laboratory. The collaborator will work to develop new methods of monitoring environmental conditions in situ to better understand dynamics within commercial farms.