A handful of positive tests for the prohibited substance Zilpaterol in France has led to an investigation of the products of equine nutrition company GAIN after it was found that all five affected horses had been fed the company's products. Testing of GAIN products subsequently returned positive results for Zilpaterol. Zilpaterol is a synthetic substance used to promote weight gain in cattle. The products in question as stated by France Galop are racehorse cubes, racehorse mix and opti-care balancer. GAIN has advised customers to cease feeding its products while an...