Boston dropped 118 ISET points and still cracks the top 10. That tells you everything about what Switzerland’s recalibrated index is—and isn’t—rewarding.
Executive Summary: Switzerland’s ISET was recalibrated for April 2026—with the standard deviation reset to 100, heavier component weighting, and mastitis resistance replacing SCC—it reshuffled the entire genomic top 10. Progenesis Torchlight (Sheepster x Gameday) takes over at +1519 ISET, pushing former #1 Monset to 4th after a 101-point drop; four new bulls entered the top 10, four fell out, and the #1-to-#10 spread compressed to just 47 points. The biggest rank mover is DG Caarma, jumping from 23rd to 6th on raw production (+2,212 kg milk, IPL 153)—but his udder’s at 103 and fertility at 98, so he’s not a free lunch. On the proven side, Peak Powerhouse surged to #1 Interbull at +1520 ISET with 82% reliability, while domestic anchors Topstory (+1420, 91% rel) and Ranger (+1398, 99% rel) sit 100+ points below the genomic leaders with far less re-ranking risk. Five of the top 15 genomic bulls carry Gameday as MGS—if your herd’s already deep in that line, Lars-Acres Caruthers-S (#3, +1505, Ice Cube-S x Van Gogh) is probably your most valuable outcross play right now. Any matings still queued to Beautyman, Logic, or Fireking based on December rankings need a hard second look; all three dropped out of the top 15 under the new weights.
The April 2026 Swiss proof run isn’t just a routine update—it’s a structural reset. The ISET has been recalibrated (standard deviation reset to 100), with greater emphasis on fat and protein production, and mastitis resistance now replaces somatic cell count in the index. Every published April 2026 ISET value has dropped relative to December 2025, many by 60–120 points, but the rankings—not the raw numbers—tell the real story. An April 2026 ISET above 1500 now signals a truly elite bull; old 1600+ levels are no longer the expectation under the new scale.
Progenesis Torchlight (Sheepster x Gameday) emerges as Switzerland’s new genomic ISET leader at +1519 in the April 2026 run, leapfrogging from 5th at +1584 in the December 2025 Swiss ISET genomic evaluation. TGD-Holstein Monset, December’s dominant #1 at +1603, slides to 4th at +1502 in April 2026—a relative repositioning that reflects how the new production-weighted formula punishes moderate-milk, high-functional profiles when components don’t fully compensate. For AI companies, the shift in power toward more extreme production profiles at the very top of a traditionally Swiss-domestic-friendly system is significant. For breeders, this recalibration demands fresh thinking on sire stacking and what “balance” now costs in ISET points.
On the daughter-proven Interbull side, Peak Powerhouse moves into the #1 Interbull daughter-proven position in the April 2026 Swiss ISET evaluation at +1520 ISET, driven by extreme production (2,530 kg milk, +135 kg fat, +113 kg protein) that aligns closely with the new weighting of fat and protein. OCD Trooper Sheepster, December 2025’s Interbull #1 at +1537, comes in at +1467 and the second spot in April 2026.
What Changed at the Top?
Genomic ISET Top 10 Reshuffle (December 2025 vs April 2026)
The April 2026 Swiss genomic ISET top 10 retains 6 bulls from the December 2025 Swiss genomic ISET top 10 and adds 4 new entrants. Here is the structural picture with both runs and explicit movement:
| Apr 2026 Rank | Bull | Pedigree | ISET Apr 2026 (CH ISET) | ISET Dec 2025 (CH ISET) | Rank Dec 2025 | ISET Δ (Apr–Dec) | Status |
| 1 | Progenesis TORCHLIGHT | Sheepster x Gameday | 1519 | 1584 | 5 | −65 | Up in rank |
| 2 | Cookiecutter HADLEY | Pattern x Gameday | 1513 | 1566 | 6 | −53 | Up in rank |
| 3 | Lars-Acres CARUTHERS-S | Ice Cube-S x Van Gogh | 1505 | — | — | — | New entrant |
| 4 | TGD-Holstein MONSET | Hadley x Gameday | 1502 | 1603 | 1 | −101 | Down in rank |
| 5 | Race | Ranking x Rover | 1489 | 1562 | 8 | −73 | Up in rank |
| 6 | DG CAARMA | Percival x Altazazzle | 1482 | 1515 | 23 | −33 | Major climber |
| 7 | Progenesis TIMEOUT | Peregrine x Dzunda | 1476 | 1584 | 4 | −108 | Down in rank |
| 8 | Sous-Moron BOSTON | Casting x Gameday | 1475 | 1593 | 2 | −118 | Major faller |
| 9 | Les Verdaux EGAN | Hadley x Gordon | 1474 | — | — | — | New entrant |
| 10 | Eichhof DOVER | Troy x Topstory | 1472 | 1531 | 18 | −59 | Major climber |
In the April 2026 Swiss genomic ISET run, the spread between #1 Torchlight (+1519) and #10 Dover (+1472) is 47 ISET points. In the December 2025 Swiss genomic ISET run, the same band between #1 Monset (+1603) and #10 B.O.A. Fireking (+1549) was 54 points. The recalibration has squeezed the elite into a narrower absolute band, so every 5–10 point gap at the top is now more meaningful.
Top-10 Trait Averages: December 2025 vs April 2026
Using the published Swiss genomic ISET lists, the structural shift shows up not just in ranks but in trait averages:
| Metric (Genomic Top 10) | Dec 2025 (approx.) | Apr 2026 (approx.) |
| Average milk (kg) | ≈ +1,560 kg (Monset 1,217; Boston 1,275; Timeout 1,527; Torchlight 2,106; Hadley 1,942; Logic 1,408; Race 1,812; Lebron 1,589; Fireking 1,562; Keylan 1,616) | ≈ +1,660 kg (Torchlight 1,954; Hadley 1,891; Caruthers-S 2,180; Monset 1,217; Race 1,808; Caarma 2,212; Timeout 1,443; Boston 1,290; Egan 1,956; Dover 1,420) |
| Fat kg pattern | Already high (most bulls +85–140 kg fat) | Consistently high; most bulls >+100 kg fat (Torchlight 130; Hadley 130; Race 111; Caarma 131; Dover 107) |
| ITP pattern | Strong type bulls like Monset (130), Boston (116), Beautyman (143) | Still strong, slightly more clustered: Egan 133; Monset and Dover 130; Torchlight 120; Hadley 121 |
The pattern is clear: average milk and fat kilos in the top 10 have nudged upward, while type remains strong but no longer defines the very top by itself.
Drop-Outs From the December 2025 Genomic Top 10
Four bulls fall out of the Swiss genomic ISET top 10 when we move from December 2025 to April 2026:
- TGD-Holstein BEAUTYMAN (Globed x Astral): December 2025 Swiss genomic ISET #3 at +1586; in April 2026, he is at +1427 ISET and well outside the top 20. His April production—+1,141 kg milk, −0.02% fat, +0.17% protein—and functional strengths (ITP 143, IFF 130) are no longer enough in a more production-heavy index.
- Vatland Hendel LOGIC (Bite x Taos): December #7 at +1563; April 2026 rank 17 at +1451. He offers +1,487 kg of milk, +100 kg of fat, and +75 kg of protein, but a relatively weaker type (Udder 96, Format 94) is now more exposed, as component leaders are crowding the top.
- swissgen LEBRON (Alvin x Star): December #9 at +1551; April rank 16 at +1453. He remains a strong bull with fertility 122, calving maternal 126, and ITP 125, but sits just outside the April 2026 Swiss ISET top 10 under the recalibrated system.
- B.O.A. FIREKING (Solo x Improbable): December #10 at +1549; April 2026 around rank 25 at +1432. His April figures—+1,489 kg milk, +0.12% fat, +0.16% protein, ITP 131, fertility 113—still define a robust sire, but the new ISET weighting prefers even stronger production.
The Big Movers: Up, Down, and Out
Major Climbers
DG CAARMA (Percival x Altazazzle, NL) is the biggest structural climber in the April 2026 Swiss genomic ISET top group. He moves from 23rd at +1515 in the December 2025 Swiss genomic ISET evaluation to 6th at +1482 in the April 2026 run. His April proof shows +2,212 kg of milk, +131 kg of fat, +94 kg of protein, and an IPL of 153—the highest in the current top 10. The price is a narrower functional profile: Udder 103, fertility 98, and moderate feet/legs (118).
Eichhof DOVER (Troy x Topstory, CH) climbs from 18th at +1531 in December 2025 to 10th at +1472 in April 2026. Dover brings +1,420 kg milk, +107 kg fat with +0.53% fat, +75 kg protein with +0.30% protein, ITP 130, Udder 118, Format 120, and longevity 116. He’s a classic balanced platform sire: strong type, good production, and sensible fitness.
Lars-Acres CARUTHERS-S (Ice Cube-S x Van Gogh, CH) is a completely new face at #3 with +1505 ISET in the April 2026 Swiss genomic ISET run. He offers the highest milk in the top 10 (+2,180 kg), with +101 kg fat, +82 kg protein, fertility 123, and persistency 120. Component percentages are modest (+0.12% fat, +0.10% protein), but his volume and fertility make him a high-output, high-fertility outcross relative to the usual Gameday/Ranger/Troy lines.
Les Verdaux EGAN (Hadley x Gordon, CH) debuts at #9 with +1474 in April 2026. He has the highest ITP in the genomic top 15 at 133, with Format 125, Feet/Legs 123, and Udder 122. Egan is the go-to option for herds that want to stay in the ISET top band without compromising top-tier type.
Major Fallers
TGD-Holstein MONSET (Hadley x Gameday, CH) drops from #1 at +1603 in the December 2025 Swiss genomic ISET run to #4 at +1502 in April 2026 (−101 points). His April profile remains strong: +1,217 kg milk, +96 kg fat, +66 kg protein, ITP 130, Udder 129, longevity 125, fertility 119. He hasn’t failed; he’s been outpaced by bulls whose production profiles fit the recalibrated ISET slightly better.
Sous-Moron BOSTON (Casting x Gameday, CH) falls from #2 at +1593 in December 2025 to #8 at +1475 in April 2026 (−118 points, the largest drop among the December top 10). His April profile—+1,290 kg milk, +83 kg fat, +64 kg protein, longevity 130, fertility 125, calving maternal 122—marks him as one of the best health/fertility sires in the top group, but his more moderate production now costs top-end ISET points.
Progenesis TIMEOUT (Peregrine x Dzunda, CA) moves from #4 at +1584 in December 2025 to #7 at +1476 in April 2026 (−108 points). Timeout maintains exceptional fat percentage (+0.87%) and strong components (+139 kg fat, +73 kg protein), but with +1,443 kg milk, he is outgunned by the very top volume sires. He’s now more of a targeted components bull than an all-around index leader.
Notable Drop-Outs
TGD-Holstein BEAUTYMAN is the clearest example of a bull whose Swiss ISET leadership was heavily dependent on the pre-2026 weighting. His ISET drops from +1586 in the December 2025 Swiss genomic ISET run (rank #3) to +1427 in April 2026, and he falls out of the top 20. His April production profile—+1,141 kg milk, −0.02% fat, +0.17% protein—combined with top-end type (ITP 143) and strong fitness (IFF 130) is no longer prioritized by the recalibrated, production-heavier ISET. He still has a role as a functional/type sire, but not as a front-line index driver.
What the ISET Is Rewarding This Run
The recalibrated April 2026 Swiss ISET clearly rewards high milk volume plus strong components, with functional traits still important but less able to carry a bull into the very top on their own.
The Dominant Trait Package in April 2026
Across the April 2026 Swiss genomic ISET top 10:
- Average milk ≈ +1,660 kg, up from ≈ +1,560 kg in December 2025, with Caruthers-S (+2,180 kg) and DG Caarma (+2,212 kg) defining the high end.
- Fat kilos are consistently high: Torchlight +130 kg, Hadley +130 kg, Race +111 kg, DG Caarma +131 kg, Dover +107 kg.
- Component percentages remain positive to strongly positive; several bulls combine high volume with +0.30% or more fat.
ITP values in the April 2026 genomic top 10 cluster between 110–133, with Egan (133), Monset and Dover (130), Torchlight (120), and Hadley (121) at the high end. Longevity averages above 120 in the top 10, led by Race (136), Boston (130), and Hokovit Galileo 6 (129), and fertility averages around 109, with standouts like Caruthers-S (123) and Monset (119).
Trait Trade-Off Clusters
This run reveals three actionable clusters:
- Production rockets: Torchlight, DG Caarma, Caruthers-S. These bulls sit at the very top of the Swiss ISET ranking, primarily due to their production horsepower and strong IPL. Trade-off: they often show weaker points in fertility or udder (e.g., Caarma Udder 103, fertility 98; Torchlight fertility 100, temperament 92).
- Balanced platforms: Monset, Dover, Egan. These bulls combine strong but not extreme production with high type and solid fitness. They sit 15–40 ISET points below the #1 bull, but offer lower multi-trait risk.
- Functional specialists: Boston, Race, and bench bulls like Swissgen Pompon. These bulls preserve very high longevity and fertility and often offer excellent calving traits, but give up some ISET relative to the production rockets.
For elite breeders, the April 2026 ISET selection is about deciding where on that triangle—production, balance, robustness—they want their sire portfolios to sit.
Stud Power, Family Power, and Outcross Space
Stud and Country Representation
In the April 2026 Swiss genomic ISET top 15, Swiss domestic breeding entities (TGD-Holstein, swissgen, Hokovit, Eichhof, Sous-Moron, Rhein-Valley, Les Verdaux) account for 7 bulls. Progenesis holds two top-10 genomic slots (Torchlight #1, Timeout #7), and Cookiecutter contributes Hadley (#2) and Hoedown (#11) into the Swiss top genomic list. DG Caarma adds a strong Dutch presence, and Race represents a German sire evaluated within the Swiss ISET system.
Bloodline Concentration
The April 2026 Swiss genomic ISET top 15 shows clear bloodline concentration:
- GAMEDAY as maternal grandsire for five of the top 15 bulls: Torchlight, Hadley, Monset, Hoedown, and K-Star-Fs Alcatraz.
- HADLEY as sire of Monset and Egan, while also ranking #2 himself in the April 2026 genomic list.
- TROY as sire of Dover and Hokovit Galileo 6.
This concentration implies that herds already heavy in Gameday, Hadley, or Troy on the female side risk accelerating inbreeding if they load their matings with the current Swiss genomic ISET top bulls without a diversification plan.
Outcross Opportunities
Given that concentration, high-value outcross bulls within the April 2026 Swiss genomic ISET list are:
- Lars-Acres CARUTHERS-S (Ice Cube-S x Van Gogh): No Gameday, Ranger, or Troy in his immediate pedigree. He offers elite milk (+2,180 kg), strong fertility (123), and high persistency (120), making him the premier production + fertility outcross bull in the current top 3.
- Race (Ranking x Rover): A German-based sire with Ranking and Rover, offering longevity 136, calving direct 118, and calving maternal 119. He’s particularly attractive for inbreeding-sensitive herds that also want to reinforce survival and calving ease.
- Progenesis TIMEOUT (Peregrine x Dzunda): Avoids the main dominant sires and provides extreme fat percentage (+0.87%) with +139 kg fat. He is a targeted tool for herds where a higher fat test is a major revenue driver and bloodline diversification is a priority.
Volatility, Reliability, and Proof-Run Risk Profile
Genomic Reliability Landscape
The April 2026 Swiss genomic ISET top group operates within a narrow reliability band of roughly 71–75%. This means:
- Every bull in the top 15 sits in the genomic prediction reliability zone, not high-reliability proven territory.
- The observed churn—4 new bulls in the top 10 and 4 drop-outs between December 2025 and April 2026—is exactly what you’d expect at this reliability level.
Bulls like Torchlight (72% reliability), Caruthers-S (71%), and Egan (72%) may move substantially as daughter groups expand. This is why the article positions them as high-impact, high-volatility plays rather than permanent fixtures.
Domestic Daughter-Proven Stability
The domestic Swiss daughter-proven ISET list offers a stability counterweight:
- Topstory (Altazazzle) leads the April 2026 domestic daughter-proven Swiss ISET at +1420 with 91% reliability, +2,360 kg milk, and ITP 124.
- Ranger (Rubels) sits at +1398 with 99% reliability, +1,429 kg milk, +0.42% fat, and ITP 125.
For proof-based programs, these bulls establish a “stability band” about 120–130 ISET points below the genomic leaders, but with reliability in the 90–99% range. For many herds, that gap is an acceptable price for risk reduction.
Interbull Daughter-Proven Re-Ranking
On the Interbull Swiss ISET list:
- Peak Powerhouse rises to +1520 ISET in April 2026, with 82% reliability, +2,530 kg of milk, +135 kg of fat, and +113 kg of protein.
- OCD Trooper Sheepster moves from +1537 in December 2025 to +1467 in April 2026, now #2.
- Progenesis Pattern at +1451 and Progenesis Wesson at +1445 continue to anchor sire-of-sons roles backing bulls like Hadley.
Even in the daughter-proven Interbull set, the April 2026 recalibration reshuffles rankings, though far less dramatically than in the genomic lists.
Strategic Sire Roles and Mating Concepts for Elites
1. Index Leaders for Aggressive Genomic Programs
Use these bulls if your herd prioritizes maximum genetic gain and can tolerate genomic volatility in a 2–3 year semen pipeline.
- Progenesis TORCHLIGHT (+1519, 72% rel, April 2026 Swiss genomic ISET): High-production leader with +1,954 kg milk, +130 kg fat, +88 kg protein, IPL 151, ITP 120. If your herd is targeting rapid index gains and already has solid fertility, Torchlight is a top pick; be cautious in situations where temperament is critical (robot herds, parlors with nervous cows), as his temperament index is 92.
- Cookiecutter HADLEY (+1513, 73% rel, April 2026 Swiss genomic ISET): Balanced high-index sire with +1,891 kg milk, +130 kg fat, +84 kg protein, ITP 121, and good calving maternal (110). If you’re building sire stacks for genomic programs (sons, bull dams), Hadley is a core building block, particularly on outcross cow families.
- DG CAARMA (+1482, 72% rel, April 2026 Swiss genomic ISET): If you need maximum production in high-input housed systems, Caarma’s +2,212 kg milk, +131 kg fat, +94 kg protein, and IPL 153 are unmatched in the current top 10. Only use him where you can pair him with cows carrying strong udder and fertility genetics, as his udder (103) and fertility (98) are weak points.
2. High-Reliability Anchors
Use these bulls to stabilize your herd or proof program if your genomic lineup already carries significant risk.
- Topstory (+1420, 91% rel, April 2026 domestic Swiss ISET): If your herd wants a reliable ceiling with strong production and type, Topstory is a prime choice—+2,360 kg milk, good solids, and ITP 124. He is particularly useful on donor cows where embryos will be marketed into more conservative, proven-biased markets.
- Ranger (+1398, 99% rel, April 2026 domestic Swiss ISET): If your conception rate or herd economics can’t tolerate volatility, Ranger is the “do-no-harm” reliability anchor—high milk, strong fat %, and proven type and fitness. He suits both commercial and seedstock herds that want proven stability over cutting-edge rankings.
- Peak POWERHOUSE (+1520, 82% rel, April 2026 Interbull Swiss ISET): If your herd can use foreign-proven sires, Powerhouse is a natural transition bull between genomic leaders and domestic proofs. He fits high-output, housed Holstein herds that already employ Interbull genetics and want a high-index but more reliable anchor.
3. Health/Fertility Specialists and Corrective Sires
Use these bulls if your main herd problem is fertility, longevity, or calving, and you can accept a small ISET discount.
- Sous-Moron BOSTON (+1475, 72% rel, April 2026 Swiss genomic ISET): If your herd’s reproduction KPIs are weak, Boston’s longevity 130, fertility 125, and calving maternal 122 offer a powerful corrective profile while still keeping you in the top-10 ISET band. He’s ideal to stabilize high-output but fragile cow families.
- Race (+1489, 71% rel, April 2026 Swiss genomic ISET): If cow survival and calving ease are your primary constraints, Race’s longevity 136, calving direct 118, and calving maternal 119 make him the go-to bull. He’s well-suited to heifers and to herds that have seen too many difficult calvings from extreme-production sires.
- Swissgen POMPON (+1390, 71% rel, April 2026 Swiss genomic ISET): If your herd has had mastitis or reproductive issues, Pompon’s fertility 130 and longevity 133 warrant a place as a bench bull even at a slightly lower ISET. He’s particularly valuable as a “health anchor” in multi-bull programs.
4. Type/Show-Leaning Sires With Index Discipline
Use these bulls if you run type- or show-focused herds but refuse to walk away from the index.
- Les Verdaux EGAN (+1474, 72% rel, April 2026 Swiss genomic ISET): For type herds that still want multi-trait strength, Egan’s ITP 133, Format 125, Feet/Legs 123, and Udder 122 make him the most attractive type sire in the current genomic elite. He suits herds that already have an adequate frame and want to stamp udders and legs.
- Eichhof DOVER (+1472, 72% rel, April 2026 Swiss genomic ISET): If your classification targets focus on udders and balanced frames, Dover’s ITP 130, Udder 118, and Format 120 make him one of the safest type-balanced sires in the top 10. Robot herds with heavy classification programs can particularly benefit from his combination of udder quality and acceptable milking speed.
5. Outcross Sires for Inbreeding Management
Use these bulls if your mating program shows heavy saturation with Gameday/Hadley/Troy.
- Lars-Acres CARUTHERS-S (+1505, 71% rel, April 2026 Swiss genomic ISET): If more than roughly 30% of your current matings trace back to Gameday or Ranger within three generations, Caruthers-S should move to the top of your diversification list. He offers elite milk, strong fertility, and high persistency without stacking the dominant Swiss sire lines.
- Progenesis TIMEOUT (+1476, 71% rel, April 2026 Swiss genomic ISET): If your fat test limits milk price and you need to drive percentages without doubling down on Gameday, Timeout’s +0.87% fat and +0.27% protein make him a targeted outcross specialist. Use him on cows with solid milk volume but less extreme components.
- Beyond HI-POWER (+1469, 74% rel, April 2026 Swiss genomic ISET): If you need a non-Gameday, non-Ranger bull that still offers high index plus good longevity (125) and calving maternal (125), Beyond Hi-Power is a logical option.
6. Herd-Type Calibration
- High-input, housed herds: If your herd runs TMR, high stocking density, and high output per stall, bulls like Torchlight, Hadley, DG Caarma, and Caruthers-S should dominate the genomic segment, anchored by Ranger and Peak Powerhouse on the proven side. You gain maximum production; you give up some reliability and, for certain bulls, some fertility or udder.
- Grazing or low-input systems: If cows must walk, maintain condition on grass, and conception is critical, emphasize Boston, Race, and Pompon, and lean harder on proven Topstory and Ranger. You gain robustness and survival; you give up some index speed and peak milk.
- Robot herds: If milking speed and udder quality drive your economics, prioritize Dover, Egan, and Monset, and use Torchlight and DG Caarma more selectively where robot hardware and cow temperament can support them. You gain structural reliability in the parlor; you give up some upside in raw production.
7. 30-Day Action Plan
Within the next 30 days:
- Audit your bloodlines. Pull your current mating list and mark all matings where the dam traces to Gameday, Hadley, Troy, or Ranger within three generations. If more than ~30% of your matings fall into that category, prioritize Caruthers-S, Race, or Timeout for the next round of matings to widen your sire base.
- Re-evaluate December favorites. Specifically review any planned matings using Beautyman, Logic, Lebron, or Fireking based primarily on their December 2025 Swiss genomic ISET positions. Check whether their April 2026 ISET and trait profiles still fit your index thresholds and herd goals; if not, redirect those matings toward Monset, Dover, Boston, or Egan, depending on whether you prioritize type, balance, or health/fertility.
Key Takeaways:
- The April 2026 Swiss ISET recalibration (SD reset to 100, more weight on fat/protein, mastitis replacing SCC) compressed the genomic top 10 into a 47‑point band and pushed average milk and fat kilos higher.
- Progenesis Torchlight is the new Swiss genomic ISET #1 at +1519 (April 2026), with four new bulls entering and four dropping out of the top 10, signaling a genuinely high‑churn, medium‑reliability (≈71–75%) leaderboard.
- DG Caarma and Caruthers-S define the new production ceiling (> 2,200 kg milk, 130 kg fat), while Monset, Dover, and Egan become the key “balanced platform” sires, trading 15–40 ISET points for stronger type and fitness.
- Proven anchors Topstory (+1420, 91% rel), Ranger (+1398, 99% rel), and Interbull leader Peak Powerhouse (+1520, 82% rel) set the stability band roughly 100 ISET points below the genomic leaders—critical for herds that can’t afford big re‑ranking swings.
- With Gameday showing up as MGS in 5 of the top 15 genomic bulls, portfolios already heavy in that line should lean hard on Caruthers-S, Race, Timeout, and Pompon to manage inbreeding while still staying in the Swiss ISET money zone.
Full Lists:
- SWITZERLAND – ISET – Genomic 04/26
- SWITZERLAND – ISET – Interbull Dtr proof – 04/26
- SWITZERLAND – ISET – Domestic dtr proven 04/26
Methodology Note
This analysis uses only the official Swiss ISET lists supplied for December 2025 and April 2026, including:
- Swiss genomic ISET lists for December 2025 and April 2026.
- Domestic Swiss daughter-proven ISET list April 2026.
- Interbull daughter-proven ISET lists December 2025 and April 2026 (Swiss ISET scale).
Comparisons are based on the main ISET values, ranks, reliabilities, and trait/sub-index columns that appear in both runs. New entrants are defined as bulls present in the April 2026 top group but not in the December 2025 top group; dropouts are bulls present in the December 2025 top group but not in the April 2026 top group. The April 2026 Swiss evaluation introduced a recalibrated ISET with standard deviation reset to 100, increased weighting for fat and protein production, and mastitis resistance in place of somatic cell count; this affects absolute index values but not the underlying ranking order. All interpretations treat rankings as snapshots tied to this specific proof run; bulls with genomic-level reliabilities (around 70–75%) remain subject to re-ranking as daughter data accumulates.
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