Hugh Chester-Jones, Animal Scientist, Southern Research and Outreach Center
Jim Linn, Extension Animal Scientist

December 24, 2004

Despite efforts by many dairy producers to refine their management practices for newborn calves there is still room for improvement. The most critical factor is feeding colostrums. This important management practice continues to be a constant challenge to attain consistent colostral passive immunity transfer to calves within the first 24 hours after birth.

At the new University of Minnesota Calf and Heifer Research and Extension Facility (CHREF) in Waseca, calves are raised on contract for three dairies from 2 to 200 days of age. Blood samples are taken from calves upon arrival in Waseca and checked for total serum proteins using a refractometer. Total proteins are measured in grams/deciliter (1/10 th of a liter) or g/dl. Total serum proteins of greater than 5 g/dl are an acceptable passive immunity transfer as being equivalent to 10g/liter serum immunoglobulin G (IgG) concentrations. Although, minimum serum proteins of 5.5 g/dl or greater is an ideal target. The best time to measure serum proteins is between 1 and 3 days of age. Research has indicated that improvements in calf health and performance between low (< 9.9 g/liter IgG) vs. high (> 10 g/liter IgG) passive immunity transfer gave an overall benefit of $23/calf by weaning.

A recent serum protein profile from 214 heifer calves taken upon arrival at the Waseca CHREF indicated that 35.5% were > 5.0 g/dl, 40.2% were between 4.5 and 5 g/dl, 21% were between 4 and 4.5 g/dl, and 3.3% were < 4 g/dl. This information is shared with the respective dairy producers who, in turn, will identify areas that need improving or modify procedures on their own farm. Based on this profile, it would not take much change in management to have over 75% of the calves with successful passive immunity transfer. Short dry periods, calving stressors, seasonal factors and age of dam can contribute to variation in passive immunity transfer. This is a reminder of the 3 Q’s of colostrum management – Quickly, Quantity and Quality.

Once calves are moved from their dam to their housing system, daily monitoring of calves during the first few weeks after birth is another important period. To help everyone involved in calf management on the farm, a posted protocol for monitoring calves daily is an opportunity to improve consistency of calf heath management. An example protocol is shown below. Protocols can be laminated and posted in visible areas of the maternity area, calf barn or milk mixing and feed storage rooms.

More details of facility design and calf management protocols at the Waseca CHREF will be presented at the University of Minnesota Dairy Days–2005 , to be held January 4-14 at eight locations throughout the state. Details on the locations and agenda can be found on the Dairy Extension web site at: www.extension.umn.edu/dairy/efforts/dairydays2005.htm. For further information on this topic, contact Jim Linn (612-624-6789) or Hugh Chester-Jones (507-837-5618).