In Health Watch:Drinking milk from cows is the norm in the US. But in Europe, donkey milk is catching on.Doctors say it's closest to human milk making it ideal for babies with allergies.Anna Matranga reports from Italy.Little Elena Arevallo is a happy and healthy two-year old.But when she was just five months, her parents discovered she was highly allergic to cow's milk AND goat's milk.And, she refused all other milk replacements.Her desperate mother, an American living in Italy, heard about donkey milk.First she had to persuade - herself - it could be the solution.Eileen Arevallo says, 'if its common in Europe, if its heard of in Europe, then its not something that's absolutely unthinkable, its not as bizarre as I thought.'Donkey milk been consumed in Italy for centuries.A Children's Hospital in Turin gave it to patients with multiple allergies for the past 6 years.Study results, doctors say, are outstanding.Over 90% of the children tolerated and thrived on the donkey milk.Experts believe that's because donkey milk is the closest to human milk. It's low in saturated fats and high in vitamins.And because it's sweet, children like the taste.The hospital gets its milk from this donkey farm, the largest in Europe.Founder Giuseppe Borghi says over the past 18 years, he's provided milk to over 4,000 children.Giuseppe says, 'I feel joy when I see a healthy child and a relieved mother.'But relief comes at a price...Because donkey milk is so rare, it costs about 20 dollars a quart... a price parents like Elena's are only too happy to pay.Donkey milk is not yet readily available in the U.S. and for now most research on donkey milk is taking place in Europe.