As Chinese New Year approaches, the dog runs across the Mekong to Vietnam pick up.
Canines of all breeds are bought, bartered or stolen, mostly in Thailand's north-eastern provinces, along the Mekong river that is the border with Laos.
The dogs, sometimes sedated, are packed into plastic chicken cages concealed below floorboards of pick-up trucks destined for restaurants in Vietnam.
As many as 100 live dogs per truck are smuggled this way out of Thailand, a distance of roughly 140km through Laos to Vietnam mostly on Route 9, avoiding border checkpoints to dodge export, health and quarantine regulations.
The traders have turned to using these pick-ups because the bigger trucks used previously were easily detected by activists like one who did not want his real name used.
"Just call me Mr T," he said.
Often working undercover in Thailand and Laos, his network of informers tells him when orders for dogs have been placed and shipments made. He passes the information on to Thailand's Department of Livestock Development and the Royal Thai Police.
Dog meat has long been on the menu in Vietnam - especially in the Hanoi area - as well as in South Korea, parts of China and north and north-eastern Thailand. It is said to have medicinal properties
People eat an estimated 20 million dogs every year in China, 1.5 million to two million in South Korea, and five million in Vietnam - mostly supplied from Thailand. During festive seasons, dog meat consumption goes up because it is considered "lucky".
Mr T reckons that criminals smuggle some 2,000 dogs out of Thailand to Vietnam every month.
A tall, rangy 44-year-old with a family and a small business, Mr T likes dogs. But more than that, he dislikes the bad name the dog meat trade gives his country.
He and other campaigners - locals who disagree with the trade and thousands in Bangkok and across the country who share information through the Stop Dog Meat Trade Facebook page - are up against traditional practices and beliefs, apathy, corruption, greed and connections.
In 2003, the then governor of Sakon Nakhon province dropped a plan to abolish the dog meat trade in a district when some 300 local dog traders and butchers protested. He estimated that 17 dog slaughter houses in the Tha Rae district killed 300 to 400 dogs a day to meet local demand.
The export trade is well-organised, says Mr T. "It involves government officials as well.
Vietnamese businessmen come here and buy dogs from Thai middlemen. It's been going on for decades; it is only recently that the issue has been picked up."
A dog at the source in Thailand costs 150 to 300 baht (S$6 to S$12). The same dog can sell in Vietnam for 5,500 baht.
"Dogs are food for rich people," says Mr T.
Thai law does not specifically outlaw the export of dogs. But to take a truckload across provinces in Thailand or out of the country requires an export permit and health certification. If traders do not have these, they are charged and the dogs confiscated.
There have been numerous confiscations, many based on tip-offs from local people. There are about 3,000 rescued dogs in five government-run shelters across Thailand.
But those arrested in connection with the trade are small fry, says Mr T. "Nobody's in jail. A few people are charged and on bail. Sometimes the punishment is just a 10,000 baht fine."
National attitudes towards dog meat vary. An upcoming paper by the Soi Dog Foundation, a non-governmental organisation working with many others to stop the trade, cites surveys showing that only a small minority of Thais eat dog meat and that most people oppose the trade.
But in Vietnam, more than 50 per cent are in favour of the trade. In South Korea, foreign condemnation of dog meat consumption has produced a backlash, stoking defiant Korean nationalism.
But Mr T and other campaigners - whether they are in South Korea or Thailand - have allies: a younger middle class that is increasingly sensitive to animal welfare issues, and the power of online social media.
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