I checked www.snopes.com about the tiger story; here is the real info:
http://www.snopes.com/photos/animals/tigerpig.asp
As often happens, this appears to be a case where someone came across some unusual photos with no explanatory context, so the viewer decided to make up his own background story. The pictures are real, but the accompanying explanation about a mother tiger in California being given piglets to ease her through a depression stemming from the loss of her own cubs is fiction.
The images displayed above were taken in 2004 at the Sriracha Tiger Zoo in Chonburi, Thailand. Although the Sriracha Tiger Zoo hosts one of the world's most successful tiger breeding programs, unlike most western zoos it also offers circus- and carnival-like shows, exhibits, and interactions, including (as evidenced here) the mixture of adults and young of quite different species in the same enclosures. As described by the AWI Quarterly, a publication of the Animal Welfare Institute: The Sriracha Tiger Zoo, an hour outside of Bangkok, Thailand, is truly an amazing place. Boasting more than 400 tigers, a handful of Asian elephants, piles of crocodiles, camels, snakes and other exotic animals, the zoo has some intriguing, yet troubling exhibits.
In one glass room, a farrowing crate entombed a pig who, lying on her side, nourished both her piglets and tiger cubs. Across the hall, another glass room housed a female tiger, who fed piglets adorned in tiger-print costumes. This incongruous display was replicated elsewhere, where enclosures housed tigers, pigs, and dogs together.
In another area, a visitor could feed milk to a young tiger resting on his or her lap — a young tiger still in possession of his claws ... There was a tiger circus, not dissimilar from a circus anywhere else: tigers leaping through rings of fire, walking across a double tightrope, parading around the ring on hind legs, and riding around on the back of the horse.