The "Chihuahua Challenge" for Cinco de Mayo Fiesta, "A Celebration of Hispanic Culture," has been occurring annually since 2000 in Shreveport, Louisiana. It's orchestrated by Shreveport/Bossier City Cinco de Mayo Fiesta Inc., in partnership with Latinos Unidos del Norte Louisiana (LULAC), as a free and fun-filled event for the whole family.
Besides chihuahuas, there is music including mariachi, salsa, merengue, bachata, cumbia and reggaeton, with a salsa dance contest and much else. The Chihuahua Challenge is a chihuahua race. The yawning chihuahua, Bitsey, was a first-place winner two years running, but placed second in 2002 when the photo immediately above was taken.
Bitsy belongs to Whitney Higgins, who is squatting third in line in the middle photo, watching Bitsy run, in a photo by Marlo Villafuerte.
The last photo below, again from the Fifth Annual Cinco de Meyo in Shreveport, shows dainty young Brian Hollingsworth with his big butch dog Pertie. Oh, and the poster up top was designed by Planet Chihuahua as wallpaper for Cinco de Mayo.
Shreveport Cinco de Mayo Official Website