Can Feed Be Too Good?
Dr. Ronald L. Boman
USU Extension Dairy Nutritionist
Last month I was pleased to spend some time with a 1,000-cow dairy producer. He maintains that he gets the same amount of daily milk from his 170 Relative Feed Value (RFV) alfalfa hay that he grows and swaths in the afternoon as the 190 RFV hay that he buys. I�m happy that this principle is catching on. I have explained previously in these newsletters that hay harvested in the afternoons has increased sugar content and increased palatability as compared to hay that is harvested in the mornings. This same producer says his workers just have to find other things to do in the mornings so he can take advantage of the afternoon harvested hay.
Can we go too far with high quality in alfalfa hay and haylage? The answer is �It depends!� We must maintain a minimum level of effective fiber in the diet of lactating dairy cows to avoid throwing cows �off feed,� to maintain percent fat, and to avoid subclinical laminititis.
Alfalfa is the main fiber source for most dairies in the West. Large dairies can mix �super high quality� hay (225+ RFV) with other hay or forage before feeding and take advantage of its high level of energy and protein. These large dairies usually have access to commodities such as whole cottonseed and almond hulls which supply effective fiber. However, smaller sized dairies may have a more difficult time using �super high quality� alfalfa unless they can also follow some of the steps mentioned above. It is important to feed a �balanced ration� that includes adequate fiber.
Fine grinding of barley and corn and such processes as steam flaking allow us to utilize more of the energy contained in grains, but if we feed too much of these highly processed grains (much more than 12 lbs/day) we can cause reduced milk fat levels and even ruminal acidosis. The bottom line is that we want high quality alfalfa (180-200 RFV) and we want to capture as much energy as possible from cereal grains, but we have to use judgment and get competent nutritional advice.