I found the article from Normand St-Pierre about feeding for pounds of fat and protein to be quite interesting, and his closing comments in particular.
“In essence, dairy producers make their money on the fat and protein produced, around 7 pounds per hundredweight of milk in Holstein cows and lose money producing the remaining 93 pounds. Those who understand this reality will focus on producing the maximum amounts of fat and protein in the smallest volume possible.”
His conclusion is a ringing endorsement of the Jersey breed. The average Jersey cow on test in Ohio produces 8.3 pounds of butterfat and protein per hundredweight, leaving only 91.7 pounds of milk on the “losing” side of the ledger.
(American Jersey Cattle Association)