Computer-assisted digital image analysis and evaluation of brood development in honey bee combs

Summary The potential impact of plant protection products on honey bee brood development is of increasing concern. Regulatory authorities therefore now request studies monitoring potential adverse effects on honey bee brood development. Current methods have a number of inherent technical limitations which we have circumvented by computerization of analysis. In this article, we describe the computer-assisted digital image analysis and evaluation method of brood development in honey bee combs. With this tool it is possible to systematically evaluate brood development on the basis of high definition pictures of brood frames taken during semi-field or field scale honey bee trials. The computerassisted method enables the post-hoc analysis of virtually any number of cells, and addresses both the issues of small cell numbers as well as the traceability and verification of the data. The method and software described has been designed and compiled with the intention of providing a tool for the 100% traceable analysis of bee brood studies with gap-free, systematic documentation. This is extremely important when working under Good Laboratory Practice (GLP) conditions. By reducing the out-of-hive time, the method minimizes the impact on the bee brood, and is thus likely to increase the success rate of studies. The availability of digital images allows the post-hoc analysis of any number of cells. The automated tracing of the cells under investigation and the automated population of the cell classification data excludes manual data transcription errors and thus significantly improves data reliability.