Over and over, the lion cubs kept dying.

It was London, the 1880s.

The lioness in the London Zoo had produced 20 litters over a dozen years,

but she could never make enough milk.

And as soon as the cubs were weaned and moved on to a diet of goat meat,

they started suffering. Their limbs bowed out,

and their spine sagged. One two-month-old cub proved especially sad. She was emaciated and half-paralyzed.

She couldn't run after her playmates without staggering and falling. She also suffered from seizures and died at just three months old, and she was hardly

alone.

In 19 of the 20 litters, every single lion cub died.

When yet another litter was on the verge of death, the desperate zookeepers turned to a young

surgeon for help.

Dr. John Bland Sutton moonlighted at the zoo, dissecting animals for his research into

comparative anatomy. In examining the dead lion cubs, he found that they had soft bones,

a disease called rickets. The zookeepers asked Bland Sutton how to fix the problem. After thinking things over,

he blamed the lean goat meat that the cubs ate. He suggested switching to fattier horse meat.

He also suggested adding ground-up bones and milk. On a whim, he told the keepers to add cod liver

oil as well. It couldn't hurt.

The zookeepers tried the new diet on the ailing cubs, then spent weeks pacing and fretting.

But they need not have worried. The cubs thrived on the food, practically springing up from the dead.

Within a month, they were scampering around like Simba, playfighting,

and sounding many roars. After that, the zoo never had a problem with Ricketts again.

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