The development of the digestive system of the young animal V. The development of rumen function in the young lamb

A total of twenty-one Merino lambs varying in age from 2 to 11 weeks were slaughtered. 2. The enzymic activity of their rumen contents was measured on a variety of carbohydrates and on protein. 3. Enzymic activity was expressed as mg. carbohydrate hydrolysed/mg. protein nitrogen/hour. 4. When compared with the rumen contents of adult sheep, lactase and proteolytic activity decreased with age; maltase, sucrase and fructanase activity increased; amylase activity decreased from 2 to 11 weeks though adult values were similar to those of the 2-week-old lamb. 5. The rumen contents of the lamb were as efficient as those of the adult sheep in their ability to hydrolyse a wide variety of carbohydrates and protein.