Nature is a very cool thing! This was forwarded to me this morning and I thought I would share it.
Out in California in a Zoo a mother tiger gave birth to a rare set of triplet tiger cubs. 
Sadly, due to difficulties in the pregnancy, the cubs were born prematurely and, being tiny, they died shortly after birth. But after recovering from the delivery, the mother cat suddenly began to decline in health. Physically she was fine, but the veterinarians felt that the loss of her litter had caused the tigress to fall into a depression.
The vets then embarked on a scientific experiment. They hypothesized that if given a new litter to nurse the mother might improve. To test the validity of this they began a search trying to locate a suitable litter. Unfortunately, tiger cubs are rare and there were none to be found. So the staff at the zoo determined to try something radical.
Sometimes a mother of one species will take on the care of a different species. The doctors located a litter of newly born baby pigs, wrapped the piglets in tiger skin and placed the babies around the mother tiger. Quite a lot to ask of the piglets in the name of science. Brave little piggies! They might have become dinner, right?
Wrong! Take a look: