This summer has been an unusual one in that we have had plenty of rain resulting in growth of lush green pastures.  While this environment is great for dry cows, it provides far more energy and protein than needed resulting in the possibility of increased fattening of dry cows, particularly those with dry periods exceeding 60 days.   Research and practical experience has shown that overconditioned cows at calving are more prone to milk fever, displaced abomasums and ketosis.   Dairy producers may want to consider several options to prevent cows from overfattening.

• Ungrouped milking herds tend to overcondition late lactation cows, particularly after many producers ceased using BST.  Now is the time to establish a low group TMR with reduced concentrations of energy and protein.  Not only will this reduce overconditioning, it will reduce feed costs!
• Restrict access to lush pasture for dry cows by controlling grazing pressure to reduce availability of pasture nutrients.
• In most cases dry cows require little concentrate supplementation (less than 3 lb. per day).  Feeding concentrates is frequently used to encourage cows to come up so that they can be observed.  In such cases make sure that there is plenty of bunk space available so that each cow has ample opportunity to consume the concentrates (>30 in. /cow).
• If dry cows average a condition score of 3.5, then consider use of a confinement feeding system where the energy intake can be controlled more closely.

Research at Illinois has shown that a single dry cow TMR can be successfully implemented.  Guidelines for such systems include:

• Formulate dry cow TMR’S using about 1/3 chopped straw, 1/3 corn silage and 1/3 from some other hay, silage and concentrate.
• Dry matter intake goals are 25 to 27 lb. / cow / day.
• Energy density of .59 to .63 Mcal NE/lb. of dry matter
• Protein content of 12 – 15% providing about 1,000g/day of metabolizable protein.
• Starch content of 12 – 16%
• NDF from forage – 40 to 50% of dry matter intake.
• Total ration DM content - <55%.   If it is higher, cows will tend to sort out the more fibrous parts of the diet.
• Mineral supplementation - .4% Mg, .35 -.40% sulfur, .27 - .35% P, .5 - .6% Ca and K as low as is practically possible. Provide at least 1,000 IU of Vitamin E daily.

A goal of all dry cow feeding systems is consistency.  Make sure that straw is chopped to a length of ~2” and that the TMR is thoroughly mixed.    Make sure that bunk space is adequate and that feed is available for 20 h/day.  Avoid the use of moldy hay or straw or small grain silages harvested in the “boot” stage.   Hay crops heavily contaminated with soil must be avoided as the iron in soil will interfere with absorption of other minerals and predispose cows to metabolic disease.

This Issue:

• Dairy Pipeline, October 2009

Other resources by:

• Robert James

Other resources from:

• Dairy Science