Among backpackers, "the chicken bus" is a cliche, an expression used to mean any crowded local bus. I had the misfortune today of travelling on the prototype.
When I was leaving my guesthouse in Champasak I was told to wait out front for a bus to Pakse. Eventually a large, brightly coloured truck came by. I had to ask the manager of the guest house if this was it, and indeed it was. The truck body was open with a top, with three or four rows of transverse seats (unlike saungthaew seats, which run lengthwise). Behind and between the seats were about four tonnes of rice in bags. At the back the bags were piled to within about 50 cm of the roof, so getting comfortable would have involved lying down. That wasn't possible because there were too many people. There was a lady near the front of the bus who had a piglet in a bag - we learned about that when it made a concerted breakout attempt. She also had a couple chickens that she was carrying by the nylon line tying their feet together. And there were three large bamboo cages full of chickens and ducks on top of the bus.
With the other foreigners on the bus I speculated about how we were getting across the Mekong River. On the way to Champasak I was dropped off near a ferry stop where I crossed the river to reach Champasak itself. This time, the bus drove onto one of the cobbled together vehicle ferries. The ferry consists of three iron ship hulls connected together with timber running across them - not the most reassuring of constructs. Back on the road, we rolled along towards Pakse. About 15 miles outside Pakse, we were stuffed (with about half the population of the bus, and all the chickens on top) into a very crowded tuk-tuk. Even that didn't exactly take us to Pakse: they took us to the eastern market and we had to negotiate a ride into the center of town.
P.S. If you want to post a comment or email me to stay away from chickens, please don't. I'm aware of the dangers, and you might as well tell me to stay away from mosquitos. The difference being that I haven't been able to find a bird repellant ...