Should we pay as much attention to Protein as Butterfat

 

CONCEPTIONS  Dairy route newsletter                  Aug-Sept 2020

At the present time, butterfat carries twice the value of protein in our milk checks which is almost the inverse of five years ago.   With the heavy deductions for skim milk that is being dumped unsold, most of us have become very aggressive in use of “high butterfat” bulls (in which selection on “% butterfat” differential will yield the most in raising your milk check price).

Consumer preferences have gone away from “low fat” in favor of “low sugar” and whole milk (if not “lactose free” packages) and yogurt sales have benefitted, while the maturity of the population has helped sustain sales of ice cream and hard cheese.
As milk processing and distribution straightens out, it will pay you to have focused genetic selection in favor of higher butterfat% and protein% sire choices.

Why both butterfat % and protein % ??

The very best sources of butterfat % tend to also be good sources of protein %, while there is a suspicion that the highest protein % producers have the most active and healthy rumens, thus the better buffered rumen that results will more easily produce butterfat % as well.

It seems that, while a cow is in a negative energy state (as often occurs when a cow’s peak of yield early in lactation exceeds her feed intake) the protein being produced in the rumen gets converted into energy in the abomasum, in an attempt to catch up that internal energy need.

Thus bulls with negative protein % ratings may be more prone to metabolic disorders and the usual result of this, after ketosis, is delayed rebreeding, followed by a drop in milk production once her system identifies she is pregnant.     This will be most extreme when the sires have a high plus PTA for production volume (the sort of cow who is driven to “peak” extraordinarily).

The current need is to select for greater lactation persistency rather than high peaks, and this sort of cow usually has more even body condition scores throughout lactation and will breed back “on time”.     This sort of lactation behavior usually will express above average protein % as well as butterfat %.    

Will the future milk market demand more protein than the current market?

In spite of a lot of noise about how Genomic selection is “speeding up the generations” it still seems to take 32 months on average to bring a new heifer from conception to production.   In three years we will be producing more butterfat, will the market have changed by then??