(Reuters) - More Sanderson Farms Inc investors supported a shareholder proposal this year urging the third-largest U.S. poultry producer to stop giving medically important antibiotics to healthy chickens for disease prevention.

The proposal received the support of 43 percent of votes cast at the company’s annual meeting on Feb. 15, according to regulatory filing on Tuesday. A similar proposal last year garnered 30 percent support.

Sanderson is the only large U.S. chicken producer that has not committed to curbing the use of the drugs. It had urged investors to vote no on the proposal filed by the non-profits As You Sow and supported by charity Oxfam America.

In the United States, an estimated 70 percent of antibiotics important to fighting human infections and ensuring the safety of invasive procedures such as surgeries are sold for use on farms.

Scientists from the World Health Organization and other groups have warned that the use of antibiotics to promote growth and prevent illness in healthy farm animals contributes to the rise of dangerous antibiotic-resistant superbug infections, which kill at least 23,000 Americans each year and pose a significant threat to global health.

Sanderson, a low-cost chicken producer, in its proxy disputed WHO’s conclusions and said phasing out those antibiotics “would fundamentally change our business and our brand without good reason.”

Nevertheless, it has previously said that it has a plan to eliminate them if it is in the company’s best interest.

Rival meat suppliers have already made the move. Tyson Foods Inc has stopped using antibiotics to produce its retail line of chicken. All chicken sold under the Perdue Farms brand is from flocks that have never been given antibiotics, the company said.