The longest shot : Lil E. Tee and the Kentucky Derby / John Eisenberg. (OCLC #897135902)
150 Lil E. Tee (Race horse)
which is odd. The section of the Subject Heading Manual on “Establishing Certain Entities in the Name or Subject Authority File” says that Named Animals should be established as a name authority, specifically in a 100. The record was entered in 1995, around the time that these distinctions were in flux.
A search in the name authority file for “race horse” only produced about 13 headings of that form (like Man o’ War (Race horse), 1917-1947), but the search for that phrase in topical headings produced close to a hundred headings (including Barbaro (Race horse), born 2003), so there is still inconsistency in how these are being established.