CowSync Guide › My Herd & genetics

Simulator

Project a sire across your whole herd for several generations, or rank your herd's sires or dams for one animal.

The Genetic Simulator has two jobs, on two tabs:

• Project a Sire: "If I use this bull on my cows for several generations, where does my herd end up?"
• Find Best Matches: "For this one cow, which of my bulls is best?" (or the other way around).

Open it from Breeding → Simulator in the menu. As on the Predictor, choose American EPD, Australian WBV or Akaushi AAkA at the top right first.

Project a Sire

1. Under Simulation Parameters, click Select Sire and pick a bull. A line below tells you how many dams (cows and heifers) in your herd he'll be simulated against.
2. Drag Generations (2 to 5).
3. Drag Heifer Retention (20% to 90%): how many heifers you keep each generation.
4. Under Select For — Breeding Objective, click the one trait you're selecting replacement heifers on (for example Marbling). Each generation keeps the heifers that rank best on it.
5. Click Run Genetic Simulation. Clear starts over.

Reading the result

• Genetic Trajectory chart: pick a Focus Trait to chart. The line is your herd average each generation; the shaded band is where the middle 80% of animals land. The top right shows the Herd average from start to finish and how much it improved.
• One card per generation (Base Herd, Generation 1 and so on) with every trait's average, range, and change from the base herd, plus a BMS Trajectory (expected marble score). The trait you selected for is outlined in gold.
• AI Projection Analysis: a written explanation.
• Report downloads or shares the simulation.

Find Best Matches

1. Under Ranking Parameters, choose Sire for a Dam (pick a cow, rank your bulls) or Dam for a Sire (pick a bull, rank your cows).
2. Pick the animal in Select Dam or Select Sire.
3. Optional: Rank By traits. Leave blank for a balanced, carcass-led score.
4. Poll Preference: Any, Prefer polled or Polled only.
5. Optional: a Goal Description in plain English, like "polled black bulls, heavy on marbling". CowSync reads it when you run and fills in any setting you haven't set yourself.
6. Optional: open Filters (click Expand; Minimize closes it) to only consider animals that match: Coat Color, Strain (Black Wagyu, Red Wagyu / Akaushi), Grade (Fullblood, Purebred, F1 / Crossbred), Born after / Born before year, Registered only, Favorites only, and Trait / Index Minimums (+ Add a trait or index…, then Min and Max).
7. Click Find Her Best Sires or Find His Best Dams.

The results, headed Best Sires for Her or Best Dams for Him, score every herd animal on the calf it would produce, best first, with pages if the list is long. Until you run it, it says No ranking yet. Save any predicted calf to your herd with its add button, and use Report to download the ranking.