Purdue University	February 12, 1959
Agricultural Extension Service	DH-78
Lafayette, Indiana
MORE MILK FROM QUALITY FORAGE C. H. Noller, Dairy Department
The future of the dairy industry is dependent, not on the cow's ability to use grain, but her unique ability to convert fibrous feeds such as pasture, hay and silage into milk. It has long been known that the cow can obtain all of the necessary nutrients from forage and that she can go an entire lifetime without grain. But, it is also known that her ability to subsist and produce milk on forage is dependent on the quality of the forage. Forages are characterized by a high proportion (50-60%) of tough fibrous constituents known as celluloses and hemicelluloses. The only reason the cow can use these plant constituents and that man cannot is because the cow has billions of rumen bacteria to do the work for her. Without the rumen bacteria the nutrients in forages would have no more value to the cow than they do to man.
Although the cow can make excellent use of forages, she cannot use just any type of fibrous material and convert it into milk. Some forages, or roughages as they probably should be referred to, are of such poor quality that the cow finds it difficult to obtain enough nutrients to meet her maintenance requirement let alone supply the nutrients needed to produce milk. Although high quality forages are preferred, poor quality forages can be successfully used provided that they are properly supplemented to supply the essential nutrients required by the rumen bacteria.
The effective use of forages means fitting the forage to the rumen bacteria.
The best method is to use high-yielding immature forages which are easily converted to milk with a minimum of effort and grain. In practice, it is often necessary to feed large amounts of grain to dairy cows because of the low quality of the forages and the low amount of milk produced from the forage. The amount of grain fed is generally governed by four factors: (1) the amount and quality of forage available,
2) the physical condition of the animal, (3) the response of the cows to the additional grain, and (4) & combination of the other three factors. However, because of the low quality of most forages, large amounts of grain are fed.
As a general rule forages are our cheapest source of nutrients. In a normal year a pound of TDN (total digestible nutrients) from forage costs approximately as much as a pound of TDN from grain.

What is quality
Quality in forage is generally considered to be synonymous with value. The meaning of quality may be illustrated as follows:
Quality = Nutritive Value x Rate of Intake
This means that the amount of milk produced from forage is dependent on the forage readily consumed, and that the forage consumed contains a high concentration of the essential nutrients.