Just saw the mention of liger on Snopes, and remembered that they were mentioned as unable to reproduce? Why is that so?
Many hybrid mammals are infertile due to the differences in chromosomal structure between the two parents. For example, donkeys have 62 chromosomes and horses have 64. Their offspring is a mule, with 63 chromosomes. The mule is viable, but it cannot form its own gametes via cell meiosis because of the odd number of chromosomes.
Other interesting hybrids include:
zeedonk, a male zebra and female donkey hybrid,
zorse (also called zebroid) a zebra and horse hybrid,
and my personal favorite, the lijagulep, a hybrid of a leopard/jaguar hybrid (jagulep or lepjag) and a lion.
Some hybrids are fertile. The famous beefalo, (American bison and domesticated cows) have reproduced on occasion, even though their parents are in different genera.
Pft…forget all that chromosomal hooey. We all know that the magical nature of the liger inteferes with its reproductive ability.
According to Wikipedia, it depends on the gender. Link:
What about “bengal” cats. They are cross between a wild Vietnemese leopard like, river swimming cat and several domestic breeds.
They reproduce and are extrodinary animals. I had one (a 17 lb male) until an envious stranger stole him off my back porch. 
And my new cat can’t spell worth a damn as if you couldn’t tell from my postings! 
You mean… a cat burglar?!
Hey, Amigo, sorry for the loss of your Bengal. There are, sadly, so many dog and cat kidnappers (catnappers?) around, that no valuable (or otherwise) pet should be left out alone.
The Bengal is a cross between the Asian Leopard Cat (mostly in India and Burma as I understand it) and a domestic cat, often the Egyptian mau, a domestic spotted cat. The Bengals are spotted or “marbled” and are indeed amazing cats. We have two males, but they “only” weigh 15 and 13 pounds respectivly. They really are a hoot. They are also noted for liking water, and many will get right into the shower or tub with you.
As their ancestors came from India, we named them Zubin and Mehta. They both are only five generations away from the wild cats.
Living in the wild desert with coyotes, bobcats, mountain lions and other predators going right by the house, we never let them out at all or they’d soon be something’s lunch.
The breed is recognized now and getting more popular.
Mules are usually sterile. Howewer there have still been numerous instances of mules giving birth healthy young.
The difference in chromosome number is far from an insurmountable problem. The most obvious example of this is the Przwalski and domestic horse union. Despite differing chromosome numbers the animals are 100 interfertile. The real problem in hybridisation is not the difference in chromosome count but the amount of chromosomal re-arrangement that has occurred since the fusion or splitting of the chromosomes. Provided that the fused or split chromosomes have remained relatively unaltered then there is no real hinderance to hybridisation because they will still align perfectly normally and the offspring will still have all the required genes.
Reproduced on occasion? If by on occasion you mean several hundred offspring produced every day by a global herd numbering in the millions then yeah, I guess it happens on occasion. Beeffalo are perfectly fertile, not just occasionally.