Tests show that the animals are perfectly normal, their milk supply is perfectly safe and their offspring grows well. USDA scientists then cloned a Jersey cow they hope will be resistant to the disease by secreting a protein called lysostaphin. About 30 per cent of all cases are caused by staphylococcus bacteria. But it could be a year before Annie the cow, born in March 2000, produces milk and can be tested for mastitis. Mastitis is the most prevalent infectious disease among dairy cattle.
Infected cows produce less and poorer quality milk.
This is totally a first. The idea of manipulating genes to protect the immune system is not new but the possibility that it could work is, Bramley said. And the potential that it could save the dairy industry billions of dollars spent on treating and preventing mastitis is a boon to farmers. We're quite excited about it. If you've got cows in any number, you're going to have mastitis.