Short-Course on: How to Feed Your Lactating Cows Based on What Your Eyeballs & Brain Tell You
"Come Slip-Shod Through the Cow Shed With Me!"
Sung to the tune of
"Come Tip-Toe Through the Tulips With Me!"
Look at your cows and feed accordingly if you want to increase milk production and profit. Make the feeding of your cows a pro-active free-market activity instead of passive central planning drudgery. Forage and cows differ in ways we can't always measure. Don't rely entirely on what the formula sheet says or on some set ratio of kg feed to liters of milk produced. It is more profitable to feed according to what you see.
Learn Body Condition Scoring (BCS). 1 = very thin. 5 = very fat. Body Condition Score your cows on a regular basis, record and feed accordingly. Feed to have cow calf at a BCS of 3.5 and not drop below 2.5 BCS, recovering to 3.5 BCS when she goes dry.
If a lactating cow is too thin (<2.5 BCS) she is telling you that you aren't feeding her enough energy in comparison to the energy out-go in her milk. (Holsteins are commonly too thin because they are bred to produce lots of milk and therefore need lots of energy.) Remember that energy consumed above maintenance goes to either milk or body fat. Her BCS tells you which one. What to do? Feed her more energy - corn! If she has the genetic potential, she will give more milk. Increased milk production may be the result of the rumen microorganisms having enough energy to capture more of the rumen degradable protein - RDP (ammonia, amino acids, peptides) and use it (along with volatile fatty acids) to proliferate into more rumen bugs (which are mostly protein) that are digested in the small intestine and absorbed into the blood stream as amino acids. More rumen bugs mean more milk! Amino acids are used by the udder to manufacture milk. Feed more energy until milk production plateaus and BCS is at least 2.5. Then challenge her potential to produce even more milk by adding equal amounts of grain and soybean meal (SBM). Increase the amount of both until she plateaus in milk production.
If a lactating cow is too fat (>3.75 to 4 BCS), your cow is telling you that she is consuming excess energy in relation to the energy outgo in her milk. This may be because she doesn't have the genetic potential to increase milk production, she may be at the end of her lactation and drying up or she may not be receiving enough protein. What to do? Add one kg of soybean meal to her diet and see if she responds with more milk. Continue adding more SBM as she goes up in milk until her body condition score drops to 3.5. Then add equal amounts of corn and SBM until she plateaus in milk. SBM should be fed rather than sunflower meal (SFM). SBM is higher in RDP and four times as high in rumen undegradable protein (RUP) as SFM. Very Important! Cows must have added RUP to give more than 15 to 20 liters of milk. Feed SBM! Not SFM.
If cow is between 2.5 & 3.5 BCS, feed equal amounts of SBM and corn, increasing amount until cow plateaus in milk. It takes 1 kg each of corn and SBM to support 5 liters of milk. This will make you money. Let your eyes tell you what & how much to feed!
Roy Chapin, Ph.D. Animal Nutritionist
11145 Chapin Lane, Amity, Oregon 97101