Martin Dairy is #1 GJPI Herd in U.S. for Cows

Martin Dairy LLC, owned by the Norman Martin family of Tillamook, Ore., is the nation’s highest-ranking herd for average Jersey Performance Index™ (JPI) following the August 2026 genetic evaluations released by the American Jersey Cattle Association.

The 780-cow Martin Dairy herd leads the rankings with an average Jersey Performance Index™ (JPI) of +118 and an average Predicted Transmitting Ability for Milk (PTAM) of +270.

Sexing Technologies, South Charleston, Ohio, ranks second with its 67-cow herd averaging +112 for JPI and +424 for PTAM.

Three herds tied at +103 for average JPI, with their ranking determined first by PTA Protein (PTAP) and then PTAM, as outlined in the ranking criteria.

Diamond J Dairy, Merced, Calif., ranks third. Its 58 qualifying cows average +103 JPI, +539 PTAM and +18 PTAP. The herd also has the highest average PTAM among the top 30 herds in the ranking.

Sand Creek Dairy LLC, owned by the Haywood family of Hastings, Mich., ranks fourth with an average JPI of +103. The herd averages +351 for PTAM and +17 for PTAP.

Rounding out the top five is the herd of David L. Hogan, Tillamook, Ore. The 4,388-cow herd averages +103 JPI, +279 PTAM and +16 PTAP.

More Than 91,000 Cows Summarized

A total of 91,033 cows in 627 REAP herds were summarized in the August 2026 genetic evaluations. Across these herds, cows averaged +68 JPI. Genomic Predicted Transmitting Ability (GPTA) averages were +5M, +7F, +3P, +$82 Cheese Merit Dollars (CM$) and +14.0 Jersey Udder Index™ (JUI).

There are 237 herds among the top 25% of the breed, with an average JPI of +60 or higher. The published list of the top 76 U.S. Jersey herds includes qualifying herds averaging +73 JPI or greater.

To be included in the herd rankings, herds must be enrolled in the AJCA REAP program and have at least 10 Registered Jerseys with JPIs. Only milking cows are included.

Herd averages include Herd Register and Generation Count 4, 5 and 6 cows with at least a 92 Parent Average (PJA) that have calved within the past 15 months and have no termination code associated with the current lactation. In the case of a tie, the herd with the higher average PTAP is ranked first. If herds remain tied, average PTAM is used to determine their order.

View the complete August 2026 JPI rankings for cows and heifers.