The expression can be traced back to horse racing in the 1700s when goats were used to settle the horses. A young goat. An idiom is a turn of phrase that doesn't make sense when literally translated.
Description: GTF file is a General Feature Format File. The Gene transfer format (GTF) is a file format used to hold information about gene structure. It is a tab-delimited text format based on the general feature format (GFF), but contains some additional conventions specific to gene information.
What is a MDF file? Files given the .mdf extension contain a disc image of the information that has been saved on a CD or DVD. MDF files are similar to ISO files, but they are saved in a different format. In order for the DVD or CD data to be played back properly, the MDF file must be saved with an associated MDS file.