Lactase Persistence - Lactase Persistence in Nonhumans

Lactase Persistence in Nonhumans

Lactose malabsorption is typical for adult mammals, and lactase persistence is a phenomenon likely linked to human interactions in the form of dairying. Most mammals lose the ability to digest lactose once they are old enough to find their own source of nourishment away from their mother. After weaning, or the transition from being breast-fed to consuming other types of food, their ability to produce lactase naturally diminishes as it is no longer needed. For example, in a study performed at Ohio State University, it was found that in the time a piglet aged from five to eighteen days, it lost 67% of its lactose absorption ability. While nearly all humans can normally digest lactose for the first 5 to 7 years of their life, most mammals stop producing lactase much earlier. Cows can be weaned from their mothers milk anywhere from 6 months to a year of age. Lambs are regularly weaned at an age of about 16 weeks. Such examples suggest that lactase persistence is a uniquely human phenomenon.