Grok says:
Roughly 1.3–1.5 million head of cattle (order-of-magnitude estimate; range ~1–2 million depending on assumptions), if treating the volume as equivalent total boneless/retail beef yield per animal. Far more if limited only to typical trim/ground-beef portions from each carcass.

michiganfarmnews.com

300,000 metric tons = 300 million kg ≈ 661 million pounds.

hoosieragtoday.com

Key yields (U.S./typical commercial figures; actuals vary by breed, finish, sex, and processing):Average dressed (hot carcass) weight recently ~880–900 lb (live weights often ~1,400+ lb; dressing percentage commonly ~60–64% for fed cattle).

beefmagazine.com

Boneless, closely trimmed retail/packaged meat (steaks, roasts, ground, etc.): typically ~40% of live weight or ~55–70% of carcass weight, or about 400–550+ lb per animal for a typical finished steer/heifer (e.g., ~470–500 lb from a 1,200 lb animal; ~500–570 lb from larger ones).

howmuchblog.com

Using ~450–500 lb of usable boneless beef per head gives ~1.3–1.5 million head for the full 661 million lb.Caveats for ground beef specifically:In normal fabrication, ground beef (from trimmings + lower-value cuts) is often only ~15–40% of take-home yield (~60–200 lb per animal, commonly cited around 65–190 lb depending on cut sheet and leanness).

cattledaily.com

Ground beef is typically a blend: fatty trim (~50% lean) from fed steers/heifers + leaner trim (~90% lean) from cull cows/bulls (and imports). One fed animal might contribute ~150 lb of 50s trim; matching lean often requires additional animals or imports.

wlj.net

If grinding everything usable from each animal, the lower end of the range applies. If using only typical ground portions, the number of head rises substantially (potentially 3–10× higher). Imported product for “ground beef” is often lean trimmings or processing beef rather than finished consumer ground product from whole animals.
Other variables: cow vs. steer/heifer yields differ (cows lower dressing % and muscle); bone-in vs. boneless; fat trim level/leanness of the grind; and cooler shrink/cutting losses.

These are approximate industry averages from extension services, USDA data, and beef production sources. Exact numbers depend on the specific animals and how the beef is processed into ground product.

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