To fix this problem, the scientists tinkered with the swine’s genes to make the pig produce its own phytase in its salivary glands. When the cereal grains are consumed, they mix with the phytase in the saliva, and throughout the pig’s digestive tract the enzyme works to break down the phosphorous in the food. With more phosphorus retained within the body, the amount excreted in waste is reduced by almost 65 percent, say researchers.
The researchers who created the Enviropig say it’s not just eco-friendly, but it also cut farmers’ feed-supplement costs. If the pigs eventually become common, they could also help U.S. farmers comply with “zero discharge” rules that forbid pork producers from releasing nitrogen or phosphorus runoff.
The pigs are now being raised on test farms, and won't be available to consumers anywhere for a few years. Link