He was #31 in April. By August he’s Canada’s #1 GPA LPI sire . Here’s what actually moved this proof run.
Executive Summary: Canada’s August 2026 GPA LPI proof run just handed the #1 spot to Stantons Overhaul-P — up 159 points and 30 places from #31 in April — with zero daughters milked yet. Full sibling Stantons Blast Off P climbed even harder, from #44 to #3. Only one bull from April’s top ten survived the run, and even it slipped a spot. Five of the new top ten trace back to the same two Stantons sires, so if you’re pulling straws off this list, check your pedigrees before you stack a relationship you didn’t plan for. Average conformation across the top ten nearly doubled run over run — this cohort is moving toward more type, not just more milk. None of that touches the proven side: MACE LPI’s foreign leader, RMD-Dotterer Bolt Action-ET, hasn’t budged from #1 in either run. Chase the Stantons momentum for genomic upside if you want it, but pair against an outcross like Peak Altadestino-ET or Cristella Vertigo ET before your next mating decision.
Canada’s GPA LPI — Lactanet’s genomic parent-average ranking for young Holstein bulls — turned over almost completely between the April 2026 and August 2026 runs. Stantons Overhaul-P jumped from +3981 (April 2026, rank 31) to the new #1 at +4140 (August 2026), a 159-point, 30-place move, while full sibling Stantons Blast Off P leaped from rank 44 (+3963) to rank 3 (+4124). Only one bull from April’s top 10 is still there in August.
That survivor, Siemers SSI Rosmry Tonks-ET, actually slipped — from #1 at +4179 (April 2026) to #2 at +4126 (August 2026) — while two of April’s other anchors, valued at +4064 and +4063, dropped out of the GPA LPI Top 100 altogether by August. On a completely different bull population, Lactanet’s MACE LPI list for foreign daughter-proven bulls tells a steadier story: RMD-Dotterer Bolt Action-ET has held #1 in both runs.
What that gap is worth: the top 10’s highest Pro$ value (Adaway Reaper Myboyblue-ET, $3871) and lowest (Stantons Agent PP, $2709) are $1,162 apart. Applied across a 50-daughter sample, that’s roughly $58,100 in projected lifetime-profit difference — before a single one of these daughters classifies or milks a day. That’s the scale of what’s riding on a genomic list that can still move again.
August 2026 Genomic GPA LPI: Top 10 Sires
| Rank | Bull | GPA LPI (Aug 2026) | Previous (Apr 2026) | Change | Stud (NAAB marketing code) |
| 1 | Stantons Overhaul-P | +4140 | +3981, rank 31 | +159 | Validity Genetic Testing (724) |
| 2 | Siemers SSI Rosmry Tonks-ET | +4126 | +4179, rank 1 | -53 | Select Sires, Inc. (250) |
| 3 | Stantons Blast Off P | +4124 | +3963, rank 44 | +161 | DMV GenetiQ Services (322) |
| 4 | Stantons Target PP | +4105 | new in top 10 | new entrant | DMV GenetiQ Services (322) |
| 5 | Stantons Raise the Bar P | +4095 | new in top 10 | new entrant | DMV GenetiQ Services (322) |
| 6 | Penn-England Baldy-P-ET | +4094 | +4025, rank 18 | +69 | Select Sires, Inc. (250) |
| 7 | Peak Altadestino-ET | +4087 | new in top 10 | new entrant | Alta Genetics USA, LLC (11) |
| 8 | Adaway Reaper Myboyblue-ET | +4071 | +3947, rank 58 | +124 | Select Sires, Inc. (7) |
| 9 | Cristella Vertigo ET | +4051 | new in top 10 | new entrant | Semex Alliance (200) |
| 10 | Stantons Agent PP | +4048 | new in top 10 | new entrant | DMV GenetiQ Services (322) |
- Stantons Overhaul-P takes #1 at +4140 (August 2026), up from +3981 when it sat at rank 31 in April 2026 — the single largest position jump on the list.
- Only Siemers SSI Rosmry Tonks-ET survived from April’s top 10, and even it fell one place, from #1 to #2.
- 9 of 10 August names are new to the top 10 (five never appeared in April’s Top 100 at all); April’s #2 and #3 (+4064 and +4063) are gone from the Top 100 entirely.
- The August top 10 spans +4140 to +4048, a 92-point band — tighter than April’s 142-point spread between #1 (+4179) and the #8-tied group (+4037).
- 5 of the 10 August slots belong to the Stantons cohort, all tracing to sires Stantons Revamp P or Stantons Remover PP.
Who’s Climbing Fastest, and Why
- Stantons Blast Off P: +3963 (April 2026, rank 44) → +4124 (August 2026, rank 3), +161 points — the largest gain on the list, with milk, fat, and protein PTAs all climbing together (1383→1668 lbs milk; 89→97 lbs fat; 63→69 lbs protein).
- Stantons Overhaul-P: +3981 (April 2026, rank 31) → +4140 (August 2026, rank 1), +159 points, with the same broad-based milk/fat/protein lift as its full sibling Blast Off P (863→1147 lbs milk).
- Adaway Reaper Myboyblue-ET: +3947 (April 2026, rank 58) → +4071 (August 2026, rank 8), +124 points; milk climbed 787→1045 lbs and fat 120→136 lbs, while conformation held flat at CONF+2 — a component gain without a type gain.
- Penn-England Baldy-P-ET: +4025 (April 2026, rank 18) → +4094 (August 2026, rank 6), +69 points; milk rose 1054→1139 lbs while fat (+86 lbs) and conformation (CONF+8) held steady.
Who Fell — and Who Disappeared Entirely
- Siemers SSI Rosmry Tonks-ET: +4179 (April 2026, rank 1) → +4126 (August 2026, rank 2), -53 points. Still the highest-Pro$ bull among the top 4 at $3337, but no longer #1.
- Two former top-10 anchors valued at +4064 and +4063 in April 2026 exited the GPA LPI Top 100 entirely by August 2026 — a reminder of how fast Canada’s genomic young-bull pipeline turns over as new relatives genotype into the pool.
What Is GPA LPI Actually Rewarding Right Now?
- April’s top 10 leaned on individual high-milk outliers (Siemers SSI Rosmry Tonks-ET at 1383 lbs milk, CONF+6); August’s top 10 is reshaped around the Stantons cohort, whose conformation scores run much higher.
- Averaging the ten individual scores ourselves — this isn’t a Lactanet-published figure — top-10 conformation nearly doubled, from roughly CONF+4.7 in April 2026 to CONF+8.5 in August 2026. Stantons Overhaul-P and Stantons Agent PP both post CONF+13, versus a CONF+1-to-6 range that defined most of April’s top 10.
- Stantons Blast Off P brings more milk and component gain (1668 lbs milk, CONF+12) than Stantons Target PP, which trades a touch of milk for an even higher frame score (CONF+11, 1653 lbs milk) — both still well above April’s top-10 type average.
How Concentrated Is This Family Tree, Really?
- Stantons-line bulls hold 5 of 10 August slots (Overhaul-P, Blast Off P, Target PP, Raise the Bar P, Agent PP), all tracing to sires Stantons Revamp P or Stantons Remover PP — the latter itself ranked #1 on Lactanet’s separate domestic Top LPI list in August 2026, marketed through DMV GenetiQ Services (NAAB code 322).
- The domestic Top LPI list — Canada’s actual official index — is at least as concentrated. Select Sires, Inc. alone runs 5 of the August 2026 top 10 (Siemers Rengd Parfect-ET, Penn-England Gordon-ET, S-S-I PR Renegade-ET, Duckett Pfct Has It All-ET, Westcoast GD Blakely-ET — codes 7 and 250). In April 2026, Select Sires and Alta Genetics USA (code 11) together accounted for 9 of that run’s top 10. Stud concentration isn’t unique to the GPA LPI young-bull pool; on Canada’s flagship proven list, it’s structural.
- Overhaul-P and Blast Off P are full siblings (sire Stantons Revamp P, dam Stantons Lambda Margaret); Target PP and Agent PP share dam Stantons What It Takes P. Four of the five Stantons bulls — Blast Off P, Target PP, Raise the Bar P, and Agent PP — are marketed through Stanton Genetics; Overhaul-P alone runs through Validity Genetic Testing (NAAB code 724, Ontario, formerly Vogue Sires).
- For herds already leaning on Stantons Revamp P or Stantons Remover PP genetics, Peak Altadestino-ET (sire Peak Lorax-ET) and Cristella Vertigo ET (sire Cookiecutter Hadley-ET) are the cleanest outcross options in the August top 10.
Canada’s Proven Sire List Barely Moved — Here’s Who’s Actually on It
| Rank | Bull | LPI (Aug 2026) | Previous (Apr 2026) | Change | REL% | Stud (NAAB marketing code) |
|---|---|---|---|---|---|---|
| 1 | Stantons Remover PP | +3945 | +3873, rank 2 | +72 | 98% | DMV GenetiQ Services (322) |
| 2 | Siemers Rengd Parfect-ET | +3932 | +3914, rank 1 | +18 | 99% | Select Sires, Inc. (7) |
| 3 | Drewholme Logic PP | +3909 | new in top 10 | new entrant | 96% | Blondin Sires, Inc. (799) |
| 4 | Penn-England Gordon-ET | +3890 | +3854, rank 4 | +36 | 95% | Select Sires, Inc. (7) |
| 5 | S-S-I PR Renegade-ET | +3844 | +3862, rank 3 | -18 | 99% | Select Sires, Inc. (250) |
| 6 | Duckett Pfct Has It All-ET | +3842 | +3843, rank 6 | -1 | 96% | Select Sires, Inc. (7) |
| 7 | Peak Altahothand-ET | +3835 | +3853, rank 5 | -18 | 99% | Alta Genetics USA, LLC (11) |
| 8 | Genosource Johnboy-ET | +3830 | new in top 10 | new entrant | 98% | Sexing Technologies-TWG (551) |
| 9 | Westcoast GD Blakely-ET | +3812 | new in top 10 | new entrant | 98% | Select Sires, Inc. (250) |
| 10 | Drouner K&L Augustus P Red | +3809 | new in top 10 | new entrant | 97% | Cogent Breeding Ltd. (522) |
- Stantons Remover PP takes #1 at +3945 (August 2026), up +72 from +3873 when it sat at #2 in April 2026 — swapping places with Siemers Rengd Parfect-ET, which actually gained 18 points itself (+3914→+3932) but still slipped from #1 to #2.
- 6 of April’s top 10 are still here; the 4 new entrants (Drewholme Logic PP, Genosource Johnboy-ET, Westcoast GD Blakely-ET, Drouner K&L Augustus P Red) pushed out 4 April incumbents. Unlike the GPA LPI story, none of those 4 vanished from the Top 100 — Peak Altainscape-ET, Peak Altacrazed-ET, Siemers RZ Pazzle 34954-ET, and Siemers Renegade Rozline-ET are all still ranked (11, 18-tied, 20, and 31 respectively), just no longer in the top 10.
- Drewholme Logic PP’s #3 debut (+3909, 96% REL) is the most notable new name — it’s also tied for #3 on Conformation this run, one of the only bulls scoring well on both type and total merit.
- This is the most stud-concentrated list of the four analysed. Select Sires, Inc. alone markets 5 of the August 2026 top 10 (Siemers Rengd Parfect-ET, Penn-England Gordon-ET, S-S-I PR Renegade-ET, Duckett Pfct Has It All-ET, Westcoast GD Blakely-ET — NAAB codes 7 and 250). Add Alta Genetics USA (Peak Altahothand-ET, code 11) and two companies account for 6 of 10. April 2026 was more concentrated still: Select Sires and Alta Genetics combined for 9 of that run’s top 10.
- The takeaway for breeders: if you want certainty over upside, this list — not GPA LPI — is where to find it. Every name here has 92%+ reliability and a multi-year daughter record behind it; none of them will re-rank the way Stantons Overhaul-P might by December.
MACE LPI
| Rank | Bull | MACE LPI (Aug 2026) | REL% |
| 1 | RMD-Dotterer Bolt Action-ET | +3950 | 93% |
| 2 | Gigantic | +3910 | 90% |
| 3 | Golf | +3894 | 92% |
| 4 | Has Giroud | +3871 | 93% |
| 5 | Aurora Tyrol-ET | +3867 | 93% |
- RMD-Dotterer Bolt Action-ET leads both runs — +3927 (April 2026) → +3950 (August 2026), rank 1 in both, at 93% reliability — the steadiest bull across either analyzed index this cycle.
- Has Giroud is the standout mover: +3747 (April 2026, rank 33) → +3871 (August 2026, rank 4, 93% REL), a 124-point, 29-place climb, on par with the lead index’s biggest riser in raw points.
- Gigantic (+3810→+3910, rank 12→2, 90% REL) and Golf (+3839→+3894, rank 8→3, 92% REL) both broke into the top 5 on updated Interbull MACE-converted daughter data between the two Lactanet runs.
Conformation
| Rank | Bull | CONF (Aug 2026) | REL% | Stud (NAAB marketing code) | LPI value (Aug 2026) |
| 1 | Mattenhof Harris | +20 | 96% | Semex Alliance (200) | +3307 |
| 2 | Robella Major | +17 | 96% | Blondin Sires, Inc. (799) | +3352 |
| 3 (tied) | Drewholme Logic PP | +16 | 96% | Blondin Sires, Inc. (799) | +3909 |
| 3 (tied) | Siemers RZ Pazzle 34954-ET | +16 | 95% | Select Sires, Inc. (250) | +3767 |
| 3 (tied) | Blondin Detective | +16 | 98% | Blondin Sires, Inc. (799) | +3481 |
- Mattenhof Harris leads Conformation in both runs — CONF+18 (April 2026) → CONF+20 (August 2026, 96% REL), rank 1 in both — but its total-merit LPI (+3307) and Pro$ (-$66) sit well below the leaders on other lists: a pure type specialist, not a total-merit play.
- Robella Major is the big mover: CONF+15, rank 6 tied (April 2026) → CONF+17, rank 2 (August 2026, 96% REL), with its LPI value also climbing (+2886→+3352).
- Drewholme Logic PP is a new entrant at CONF+16 (rank 3, tied, 96% REL) that also carries LPI+3909 — high type and high total merit at once, a rare combination on this list; it also ranks #3 on Lactanet’s separate domestic Top LPI list, August 2026.
A New Genomic Conformation Leader With Show-Ring Royalty Behind Him
| Rank | Bull | Conf (Aug 2026) | LPI (Aug 2026) | Pro$ |
|---|---|---|---|---|
| 1 | Jacobs Spear P | +20 | +3900 | $2057 |
| 2 (tied) | Character Andres | +19 | +3838 | $1676 |
| 2 (tied) | Progenesis Alastor | +19 | +3790 | $1549 |
| 2 (tied) | Progenesis Aksel | +19 | +3676 | $1454 |
| 2 (tied) | Walnutlawn PG Brightstar | +19 | +3651 | $1336 |
| 2 (tied) | Sabbiona Knockout ET | +19 | +3647 | $966 |
| 2 (tied) | Dairy-Doc Razor P | +19 | +3609 | $1191 |
| 2 (tied) | Blondin Pilot | +19 | +3372 | $218 |
- Jacobs Spear P debuts at #1 with +20 Conformation (+3900 LPI, 2057Pro2057Pro) — the single highest Conformation score of any bull named anywhere in this piece, genomic or proven.
- He’s sired by Fraholme Vec Triton PP, who sits at #43 on this same list at +16 Conformation (+3889 LPI) — confirmed directly from the source PDF.
- acobs Spear P’s dam line runs a VG-86 (1-yr) by Allgaud, out of a VG-87 (3-yr) by Ranger-Red, out of an EX-93 by Lautrust, out of Erbacres Snapple Shakira-ET EX-97. Shakira is a two-time Grand Champion of the World Dairy Expo International Holstein Show (2021 and 2023) and Supreme Champion both years, owned by Ferme Jacobs and partners of Cap-Santé, Quebec (World Dairy Expo, 2023; World Dairy Expo, 2021) — the same “Jacobs” name behind the new #1 genomic Conformation bull.
- Character Andres holds #2 at +19 Conformation, tied with six other bulls at the identical value (Progenesis Alastor, Progenesis Aksel, Walnutlawn PG Brightstar, Sabbiona Knockout ET, Dairy-Doc Razor P, and Blondin Pilot). Per Bullvine editorial records, Character Andres was #1 on this list’s April 2026 run — a one-point, one-place slip in a single proof run, though that April comparison wasn’t independently reviewed for this piece.
How to Use These Sires This Season
- Genomic momentum plays (for herds chasing rapid total-merit gain and comfortable with genomic risk): Stantons Overhaul-P and Stantons Blast Off P posted the two largest GPA LPI jumps of the run (+159 and +161) and can be used now, understanding their profiles will move again once daughter data arrives.
- Proven, low-volatility anchors (for herds wanting certainty over upside): RMD-Dotterer Bolt Action-ET has held #1 MACE LPI (93% REL) across both the April and August 2026 runs, and Siemers SSI Rosmry Tonks-ET has held a top-2 GPA LPI position in both runs.
- Type-correction specialist (for herds prioritizing frame and type-classification over total-merit climbing): Mattenhof Harris leads Conformation nationally at CONF+20 (96% REL, August 2026), though its below-average Pro$ (-$66) makes it a targeted mating, not a herd-wide sire.
- Dual-purpose bridge sire (for herds wanting type improvement without giving up total-merit rank): Drewholme Logic PP posts CONF+16 (96% REL) alongside LPI+3909 (both August 2026), a rarer combination than single-trait specialists offer.
- Outcross options (for herds already saturated with Stantons genetics): Peak Altadestino-ET and Cristella Vertigo ET sit at comparable GPA LPI levels (+4087 and +4051) on unrelated sire lines (Peak Lorax-ET and Cookiecutter Hadley-ET).
Within 30 days: pull your current young-sire lineup and flag any bull tracing to Stantons Revamp P or Stantons Remover PP — with 5 of the August 2026 GPA LPI top 10 sharing those two sires, herds already using Stantons genetics risk stacking relationship faster than daughter data can catch up. Pair against Peak Altadestino-ET or Cristella Vertigo ET where an outcross is needed.
- CANADA – GLPI – Genomics – Rel. in Canada 08/26
- CANADA – Top LPI – Domestic – Dtr proven – 08/26
- CANADA – Top LPI – Mace – Dtr proven – 08/26
- CANADA – Conformation Bulls – 08/26
- CANADA – Conformation Genomic Bulls – 08/26
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Methodology Note
This analysis draws on eight Lactanet Canada bull-list PDFs: the April 2026 and August 2026 Top 100 GPA LPI (genomic young bulls), Top 100 LPI domestic daughter-proven, Top 500 MACE LPI foreign daughter-proven (meeting minimum requirements), and Top 100 Conformation daughter-proven lists. Four indexes were present. GPA LPI led this analysis by top-10 volatility score (18, versus MACE LPI’s 16, Conformation’s 11, and domestic Top LPI’s 10), even though domestic Top LPI is Canada’s official primary total-merit index — GPA LPI leads on movement here, Top LPI leads on authority, and because it scored lowest on volatility among the four with no editor notes specifying otherwise, domestic Top LPI is referenced only in context (e.g., Stantons Remover PP’s own #1 domestic Top LPI standing, and Drewholme Logic PP’s #3) rather than given a full secondary-index section. MACE LPI and Conformation, the next-highest-volatility indexes, were analysed as the two secondaries.
Bulls were matched between the April and August 2026 runs by NAAB code first and by full registration number as a fallback (necessary for several MACE LPI foreign bulls that lack a NAAB code); any bull without a matching ID across both runs was classified as a new entrant or drop-out rather than assigned a guessed prior value. Rank was taken directly from each source list as published; where multiple bulls shared a tied rank, all tied bulls are reported at that shared rank rather than an invented sequential position. Genomic/proven status was taken as a list-level fact — GPA LPI is a genomic parent-average ranking by definition, while the MACE LPI and Conformation source files are explicitly labelled daughter-proven — not inferred from reliability data. No reliability % is published on the GPA LPI source list, and that gap is flagged rather than estimated. Stud/AI-marketing company names were resolved by cross-referencing each bull’s NAAB marketing code against the NAAB-CSS public marketing-code directory (naab-css.org), current as of this writing. This worked cleanly for the GPA LPI top 10, the Conformation top 5, and the domestic Top LPI top 10 (referenced in context above), all of which carry a NAAB code on nearly every source row. It did not work for most of the MACE LPI top 5: that list’s foreign-origin bulls (Gigantic, Golf, Has Giroud) appear to have no NAAB marketing code assigned at all, and Aurora Tyrol-ET’s code could not be confidently isolated from the source PDF’s column alignment; only RMD-Dotterer Bolt Action-ET’s code (7, Select Sires) was unambiguous. Where a code could not be confidently resolved, stud is left not reported rather than guessed.
No base change or evaluation-system update was noted within the source PDFs themselves, but Lactanet’s public documentation confirms the LPI formula changed at the April 2026 release: the Production subindex’s Fat:Protein weighting for Holstein moved from 60:40 to 40:60 (favouring higher-Protein bulls), Calf Health was added to the Holstein Health & Welfare subindex, and the routine annual genetic base was rolled forward, per Lactanet’s April 2026 LPI Production subindex update and April 2026 Base Change Summary. Because that change took effect at the April 2026 run — the earlier of the two runs compared here — both the April and August 2026 figures in this analysis already reflect the same post-change formula and base, so the movements reported above are on a consistent scale and are not an artifact of the reweighting.
Limitations: These are national genetic-evaluation rankings. Lower-reliability genomic and foreign MACE-converted sires in particular can and will re-rank again as daughter data accumulates, and how any individual bull performs in a specific herd depends on management, environment, and the cow he’s mated to — a proof value is not a guarantee. We welcome producer feedback, corrections, and case studies for future proof-run coverage.
