This is Shep O'Neal with the VOA Special English Agriculture Report.

Veterinarians are a first line of defense not only for diseases that affect animals, but also those like bird flu that can spread to humans. Animal doctors also help protect the food supply and the agricultural economy. Diseases like avian influenza and foot-and-mouth disease can cause huge economic losses.

In the United States, there is growing demand for veterinarians. A recent study by the Journal of the American Veterinary Medical Association warns that there could soon be a shortage. Some experts worry that there will not be enough veterinarians specially trained to inspect animals raised for food.

The journal says half of all state and federal veterinarians are close to or already at the age when they could retire.

In 2004, the United States had about sixty-one thousand veterinarians. But most of them work in areas other than the care of food animals.

Some study diseases. Some work for drug companies. And about half of all veterinarians care for the more than one hundred million cats and dogs and other pets that Americans keep.

To become a veterinarian, students take two years of preparatory studies in college. They learn about animal biology and treatment of diseases.

Then, like a medical doctor, they attend four years in a college of veterinary medicine. They work in laboratories and treatment centers and learn to perform operations.

There are twenty-eight schools of veterinary medicine in the United States. Three out of four of the students are women.

Currently about two thousand new veterinarians enter the job market each year. Veterinarians must pass a test to get a license to treat animals in the state where they want to work.

The American Veterinary Medical Association is one of the oldest groups in the profession. It started in eighteen eighty-nine. The organization approves schools that teach veterinary science.

The United States Department of Agriculture established the National Veterinary Accreditation Program in nineteen twenty-one. This program gives veterinarians extra training. They learn to work with federal veterinarians and state animal health officials.

This VOA Special English Agriculture Report was written by Mario Ritter. You can download transcripts of our reports at voaspecialenglish.com. To send us e-mail, write to special@voanews.com. This is Shep O'Neal.

veterinarian :獸醫(yī)

accreditation :鑒定資格