SPRINGBORO, Pa. -- Even rabbits can't breed fast enough for Tracy Murphy's customers.

At Hare Today, her small farm here, Mrs. Murphy spends seven days a week slaughtering, packing and shipping rabbit. She's buying rabbit herds from neighbors and building an extra shelter to boost capacity to 500 female breeders from 200. Her freezers -- two walk-ins and a bank of industrial units in a converted garage -- are chockablock with whole four-pound rabbits, ground meat in five-pound tubes and sticks of jerky.

"When...