In 1725 the Spanish had noted that the Comanches were still using dogs for transport. By 1735 this was no longer the case, and the Comanches had more than enough horses for their own needs. However, they were now supplying them to other plains tribes through trade. The level of horse thefts by Comanches bothered the Spanish, but was bearable, and the trade with Comanches for buffalo robes and slaves was important for the New Mexican economy, so the Spanish continued to trade, but a military expedition was dispatched in 1742 which unsuccessfully tried to stop the raids.