The GeneChip Bovine Genome Array contains 24,027 probe sets for over 23,000 bovine transcripts representing 19,000 UniGene clusters. With the broadest representation of publicly available expressed sequence information, bovine researchers will be able to use this array to conduct whole-genome expression profiling of cattle for agricultural applications or as an animal model to study human disease processes. The Bovine Array design was based on content from UniGene Build 57 (March 24, 2004). The GeneChip Bovine Genome Array was designed within the Affymetrix GeneChip Consortia Program and through close collaboration with leading bovine researchers.