True protein, as the name implies, is the actual amount of protein in milk, while the former standard, crude protein, is derived from the nitrogen content in milk. Crude protein over evaluates the amount of protein in milk because it includes non-protein nitrogen. The new Federal Milk Marketing Orders, which went into effect January 1, 2000, pay for protein on a true-protein scale instead of the crude-protein scale that had been used previously in many parts of the country. The change was made because true protein is more accurately measured in the lab and is more reflective of the nutritional and manufacturing value of milk. On average, this change will decrease the protein test for dairy cows by 0.19%. While this change does not affect the price you receive for your milk (unless you have unusually high or low levels of non-protein nitrogen in your milk), it does affect the protein level that you see with your milk payment.
There has been strong support for DHIA to switch from crude protein to true protein because true protein is the national payment standard. Following a meeting of representatives of various industry groups (dairy producers, DHIA, AI organizations, and breed associations), the Council on Dairy Cattle Breeding approved a proposal stating that for samples collected on May 1, 2000 and thereafter, all protein measurements will be on a true protein basis. As part of the proposal, DHIA will not convert any data; historical records that have been completed and records in progress will not be adjusted to a true protein basis. DHIA records that are currently in progress will be based on a combination of crude protein and true protein. The committee believed that this recommendation was the simplest, most economical and efficient method to make the transition.
Official Holstein PedigreesTM will display a true protein version of all records, according to recent action by the Holstein Association's Board of Directors, which will allow one heading on a pedigree and avoid labeling each individual record. This means that the protein component of the production records on Holstein pedigrees that were completed in the past or are currently in progress will differ slightly from the crude protein or combination version calculated by DHIA.
All pedigree records will be on one basis making it unnecessary to label each record. This also avoids mixing types of protein in one lifetime total. Some re-rankings will occur when moving to pounds of true protein (see examples right). This will affect the placing of some cows on the Official Holstein Protein Leader List. However, Holstein awards, such as the PBR herd award and Gold Medal Dam, will remain unaffected because the change to true protein will occur for all records. USDA-AIPL will also adjust all records to a single basis when calculating production evaluations, so PTAs will not be noticeably affected.
In response to industry requests, the Holstein Association's Board has agreed to offer pedigrees tailored for U.S. breeders that market internationally as well as international users of pedigrees. To that end, pedigrees that list and label all records on a crude protein basis will be available at the customer's request.
There are many advantages of making this change. It is the quickest way to move forward with the more accurate scale, true protein, and put crude protein, the standard of the past, behind us. By displaying all records on a true protein basis now, there will be less confusion in the long run and all domestic pedigrees and advertisements will be able to display a seamless balance of true protein records.
Holstein Association, USA