Brown Cow - 7/10/2024 08:59

I've been genomic testing for a while, including all of my heifers the last few years. I checked this spring, and I have 26 animals with both genomic data and complete lactation records. I only looked at percent fat, percent protein, and pounds of milk. Based on my data:

+1.0% gPTA fat = + 3.6% +/- 0.36% fat
+1.0% gPTA protein = + 3.6% +/- 0.15% protein
+100 lbs gPTA milk = + 52 lbs +/- 950 lbs/ lactation milk

My takeaway is that, at least as it currently stands for jerseys, the percent component numbers are valuable. Pounds of milk, and therefore pounds of components, are almost completely worthless. I've been looking at those numbers heavily for breeding choices for about 12 years now, and my bulk tank average fat has gone from 4.3% to 5.25% without meaningful change in milk pounds. Protein is up to 3.75%, I don't remember what I started at. Maybe 3.55%?