Iowa’s largest zoo is moving to protect some of its animals from West Nile virus. Birds and horses are most at risk from the potentially deadly virus. Blank Park Zoo in Des Moines is home to some members of the equine family and all sorts of birds, according to zoo director David Allen. The collection includes emus, flamingos, tropical song birds, parrots and a variety of waterfowl. Allen says the West Nile vaccine has -not- been approved for birds, only horses. Allen says any standing water is being mopped up or changed to prevent mosquitoes, which carry the virus, from breeding. He says some of the other zoos say flamingoes seem to be susceptible.Allen says the zoo’s collection of zebras -will- receives the vaccine, with the series of shots starting in a few days. He says the effectiveness of the vaccine, even in horses, isn’t yet known. West Nile has killed some zoo birds in other states — including penguins, ducks and flamingos.