Lumpkin said the couple was on its way back from an event with Oliver when they stopped at the Petco.
Vincent Browning and Shelly Lumpkin brought Oliver, a Ankole-Watusi steer, to Petco earlier this week where employees welcomed him "with open arms".
Thankfully no one had a cow with this fearless Texas man testing Petco's regulations.
But it seems the big lad is used to the attention - Oliver has his own Facebook page and apparently performs at shows and rodeos. They weigh an impressive 1,000 to 1,600 pounds (454 to 726 kilograms).More news: Manchester United may sign Borussia midfielder for £80m
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In a Facebook post, he said, "the awesome crew at Petco - Atascocita did not disappoint!"
Their unusually large horns have the largest circumference found in any cattle breed. He added that the staff was "super friendly and courteous". They made sure to strap a leash on to Oliver, their African Watusi and see if he would be welcomed.
And Oliver isn't the only unique critter to pay a visit to Petco.
Are ALL leashed pets really welcome at Petco?