efe-epaGuadalajara, Mexico

A Mexican researcher has created an antibiotic using frog skin, which cures inflamed cow udders without leaving a trace of toxicity in the milk.

Alfonso Islas, a professor at the University of Guadalajara, created and patented this substance dubbed "ranimicina," which uses the anti-microbial properties that frogs develop naturally to protect themselves from their surroundings.

The specialist in immunology told EFE that he did a study financed by the National Science and Technology Council to make use of the frogs bred in western Mexico to be cooked for tasty frog-leg dishes.

Islas took the scraps of frog skin discarded by restaurants, submitted them to a process of homogenization and extracted the molecules by centrifugal force. In that way he discovered 23 molecules that function as natural antibiotics.

With those molecules he created a formula capable of eliminating bacteria that cause infections in hospitals and which have become resistant to antibiotics like penicillin and its derivatives, he said.

One of his colleagues dared him to test the formula on cows, since close to 20 percent of dairy cattle suffer mastitis, or inflammation and infections of the mammary glands caused by milking machines.

The antibiotic applied to 280 ailing cows managed to cure them in five days and avoided having to remove them from the production line, which happens when treated with penicillin, because the natural antibiotic leaves no toxic residue in the milk.

This would benefit dairies by cutting the economic losses caused by having to rest sick cows until they are better, and by having to buy commercial antibiotics.

"Dairies suffer an up to 20 percent drop in milk sales and have to buy penicillin, but with our product, which we tested in three dairies, that isn't necessary, because the cow keeps producing," he said.

Islas' formula costs 2.19 pesos (11 cents) per dose, compared to as much as 40 pesos ($2.08) charged for a brand of penicillin. Besides, a 40-gram (1.4-ounce) frog skin could provide up to 100 doses.