Amber M. VanDerwarker notes that dogs have been found in the Olmec site of La Venta.
Amber M. VanDerwarker, Farming, Hunting, and Fishing in the Olmec World (Austin, TX: University of Texas Press, 2006), 36-37
In terms of animal resources, Rust and Sharer (1988) and Rust and Leyden (1994) stress the importance of aquatic vertebrates—specifically fish and turtles—in the diet of La Venta residents. Moreover, they suggest a status-related pattern in the consumption of larger terrestrial vertebrates like deer and dog. Apparently, significantly more large mammal remains were identified at mount sites than at non-mound sites in the La Venta settlement area. The pattern is interpreted to represent a positive correlation between status and the consumption of larger mammalian taxa. While this pattern is intriguing, neither Rust and Sharer (1988) nor Rust and Leyden (1994) report a faunal data in raw or summarized form, making it difficult to evaluate their arguments.