The August 2026 Genetic Evaluations were released this week and with pedigree strength, stability and reliability, the STgenetics® lineup once again delivered solid results while bringing a balanced, diverse lineup of sires to the industry. STgenetics® is humbled to be home to 7 of the top 15 sires on the Holstein Association USA Top 100 TPI® and other breed leaders around the world.
The Council on Dairy Cattle Breeding (CDCB) also updated models for deriving fertility evaluations this sire summary to better separate management effects from genetics, so female fertility trends now align more closely with what producers see on-farm, helping cows become pregnant more efficiently. Here is a brief explanation of these traits:
- New First Service to Conception (FSC) - Measures days from first service to conception relative to the breed mean. Positive PTA is desirable here and a +5 means that daughters become pregnant about 5 days sooner than the breed mean; Heritability is 3.2%.
- Updated Daughter Pregnancy Rate (DPR) – Corrected for within-herd Voluntary Waiting Period (VWP) by lactation instead of a fixed national 50-day VWP; Heritability is 2.9%.
- Updated Cow Conception Rate & Heifer Conception Rate (CCR & HCR) – These traits now account for service sire breed, mating type, gender-sorted vs conventional semen and short cycling; CCR Heritability is 2.9% & HCR Heritability is 1.4%.
For more specifics on these changes:
Spotify: https://bit.ly/457rASX
Apple Podcasts: https://bit.ly/4hNTVVO
Other New Traits:
Resistance to Diarrhea (DIA) - Genetic resistance diarrhea in calves
Resistance to Respiratory Problems (RSP) - Genetic resistance to respiratory problems in calves
Holstein Conformation Composite (HCC) from Holstein Association USA – A new conformation selection tool focused on identifying moderate, balanced and functional Holstein cows. The HCC assigns weights to 18 linear conformation traits based on their relationship with longevity, production, and balance, accounting for the correlations among the traits.
Genetic Results
Leading the way among STgenetics® sires on the Top 100 Holstein TPI® list is the newly Proven sire HOBBS at +3547 TPI. With a unique pedigree, HOBBS brings diversity, production and longevity, being +1287 Milk, +120 Fat, +56 Prot, +4.2 PL, +5.9 CCR and +2.2 LIV. He is +17.2 FSC, +1115 CM$ and is A2A2 & BB.
DOMINANCE delivered another consistent performance following the release of the August 2026 Genetic Evaluations, where he held strong in the Top 5 at +3479 TPI. DOMINANCE has a balanced portfolio of components and health traits at +189 CFP, +1046 Milk, +1114 NM$, +3.7 PL, +4.6 CCR and +1253 Eco$.
Other Newly Proven Sires
A full brother to HOBBS, HAYWARD comes in at +3463 TPI, +124 Fat, +51 Prot and +1094 CM$. HAYWARD is also +3.8 PL, +5.1 CCR, +1.7 LIV and +0.59 UDC along with being A2A2 & BB.
The next new Proven sire RAD comes from the famous CAPTAIN daughter, OCD CAPTAIN Rae 63785-ET EX-90 and secures a spot in the top 10 at +3428 TPI. From Genomic to now Proven, RAD delivers the perfect package of conformation, production and health being +1604 Milk, +76 Fat, +61 Prot, +5.1 PL and +3.0 LIV. He also brings conformation at +1.60 PTAT and +1.32 UDC.
Big Gains
BROCKINGTON made impressive gains moving up to +3406 TPI in his second appearance on the Top 100 TPI® list from Holstein Association USA. BROCKINGTON is a CAPTAIN that goes back to the NIGHTCAP daughter, GenoSource Brazen 40218-ET VG-85. He is +52 Prot +.05%, +112 Fat +.23%, +3.3 CCR and +2.8 PL. He is also +0.96 UDC & A2A2.
Consistency leader GARZA remained in the Top 15 at +3389 TPI. GARZA is +51 Prot, +143 Fat and +1123 NM$ and +2.6 PL. Rounding out the top 15 is the global sensation CAPTAIN at +3374 TPI who continues to deliver high-quality daughters, generation after generation at +1027 NM$, +1726 Milk, +61 Prot, +114 Fat and +3.4 PL.
ON-DUTY is again the top UDC sire on the Holstein Association USA Top 100 TPI® List for August at +2.17 UDC. He is also +1.75 PTAT and +3261 TPI, +47 Fat, +37 Prot, +3.1 PL and +5.3 CCR.
In Canada, JOHNBOY maintained a steady ranking on the top 100 LPI list from Lactanet at +3830 GLPI. With 807 daughters in 217 herds, he continues to bring a balanced profile to the breed being +1015 kg Milk, +103 kg Fat with +.51%, +82 kg Prot with +.36% and is +10 Conformation. The Red, Polled sire AUGUSTUS P RED is not far behind JOHNBOY at +3809 GLPI and is the top Proven Red & White GLPI sire. He is +44 Prot +.16% and +7 Conf and +11 F&L.
In Italy, STgenetics®/Inseme is home to top sire in the Italian domestic ranking, SANTRY. In the International Genomic Ranking, the STgenetics®/Inseme program continues to deliver outstanding results with three of the top 10 sires in the breed.
New Sires
STgenetics® released 37 new sires following the release of the August 2026 Genetic Evaluations. Leading this list of outstanding, diverse new STgenetics® sires is WOODFORD, a RIPCORD X Sheepster that is at +3622 GTPI, +217 CFP, +4.1 PL and +1295 Eco$, JACCUSE, a YOUDONTDAY X THORSON at +3581 GTPI, +216 CFP, +3.6 PL and HEDGE FUND, a BREAKAGE X Sheepster that is +3578 GTPI, +194 CFP, +4.1 PL and +1296 Eco$. Also among this list of new sires are some exciting Polled genetic options, including LOTHAIR P, the top Polled carrier of the breed at +3536 GTPI. He is also +70 Prot and +207 CFP. 38 SPECIAL P, a RIPCORD x Lionel, +3426 GTPI, +1108 NM$, +176 CFP and +4.3 PL.
The STgenetics® Eco$ is a simple selection index for impactful growth, combining fewer, highly heritable traits to drive the most genetic progress in areas that truly matter for the next generation. Eco$ is profitability, simplicity and sustainability all wrapped up in one index.
Leading the list of new releases for STgenetics® exclusive Eco$ index is PATRIOT 76 at +1391 Eco$. This DARTH VADER son is +3570 GTPI, +1311 NM$ and +230 CPF. Next from the same family as PATRIOT 76, comes JARIN at +1383 Eco$. A DARTH VADER x BROCKINGTON X CAPTAIN Jaele EX-90, he is bred to bring the perfect balance of performance and beautiful udders being +3531 GTPI, +1840 Milk, +227 CFP, +2.6 PL and +.60 UDC. MATCHMAKER is another well balanced, high Eco$ sire at +1292 Eco$, +3434 GTPI, +61 Prot and +2.1 PL.
This list of newly released sires also includes 27 Legend™ sires.
Colored Breed Sires
The STgenetics® colored breed lineup again had a strong day being led by sire GARLAND that came in +140 JPI and increased to +22.0 JUI. He is +469 Milk and +1.00 PTAT. SINCLAR is another Proven sire that comes in at +146 JPI, +713 Milk, +.90 PTAT and +18.5 JUI. Jersey sires CHATMAN at +185 JPI, +904 Milk and +15.4 JUI and CHAT BOX at +183 JPI, +803 Milk +.40 PTAT and +16.8 JUI are two young Jersey sires leading the way for a bright future for the STgenetics® program.
Proven sire CANADIAN CLUB continues to impress with his daughters both in the ring and in the barn with his Type and Udders at +1.30 PTAT and +20.2 JUI. CANADIAN CLUB was also the number two Conformation sire on the Top 50 Jersey Bulls for Conformation published by Lactanet at +18.
These breed-leading sires and the entire STgenetics® lineup are available in 4M™, the most innovative and fertile female-sorted semen, with 90% or higher gender accuracy. To view the full STgenetics® lineup: https://www.stgen.com/default.aspx?language=english&type=General
Located in Navasota, Texas, STgenetics® is making the world greener, more sustainable and profitable. By improving herd genetics through science and technology, we believe that the best way to predict the future is to create it, while feeding the world with our passion for the beef and dairy industries. The STgenetics® Integrated Approach to management combines cutting edge genetics, innovation driven programs and gender-sorted semen to aid farmers in improving cattle performance to feed the world while reducing their carbon footprint.