According to media reports, some Tibetan mastiffs are sold for a few thousand yuan in Xi'an, Shaanxi province, where most of the newly rich made their fortune from coal. The current price is not even close to 1 percent of their previous peak price.

According to Peng, the sharp decline in the price of Tibetan mastiffs is due to two factors.

First, they were overpriced in the past and not pure-bred. Second, they were not real Tibetan mastiffs at all.

"A reasonable price for a top pure-bred Tibetan mastiff should be around 1 million yuan," he said. "However, there are more or less only 20 real pure-bred Tibetan mastiffs in China so far. The others are all mixed-breed."

Peng admitted that he had made some money from his Tibetan mastiff kennel park during the boom years.

"I invested 6 million yuan in my kennels in the past few years," he said. "As one of the earliest such kennels in China, mine used to have many visitors. Now, few people visit, so I just keep it for myself and some friends because we are real dog lovers."

He explained that raising such animals requires a great deal of experience and knowledge, and it is very difficult for people to get involved if they lack these essential qualities.

"You cannot regard it as just a trade－as simple as buying and selling. The animals have feelings. If you cannot tell when they are in pain, you will cause them lots of problems."

"All in all, they are still animals and they should be treated well," he said.

Lin Jun, in his 40s, a hotelier in Xinzhou, Shanxi province, bought five mixed-breed Tibetan mastiffs three years ago after he saw his friends make quick money from the business.

He invested 100,000 yuan in kennels, equipment and food, but the animals got very sick or died after just two years.

"I didn't make any money from them. Instead, I lost all the investment," he said. "I don't think it is an easy business and I will not try again in the future."