The background is a screenshot of the pedigree of Orfevre and Dream Journey from the Japanese horseracing website Netkeiba. Orfevre's Japanese page, and English page. Dream Journey's Japanese page, and English page.

I recommend you try looking up your favourite (Japanese, usually, or else they may not come up) racehorses on this website, as every horse has a gallery where images of them are posted! You might find some cute photos.