Coolmore Stud resident Pierro was Australia’s busiest stallion last year with a book consisting of 220 mares.

Lonhro’s champion son finished ahead of Arrowfield Stud’s Snitzel (214) and Yarraman Park’s I Am Invincible (211) among interim figures released by the Australian Stud Book on Friday.

Fellow Hunter Valley sires Smart Missile (210), Sebring (192) and Fastnet Rock (189) were next on the leader-board ahead of Eliza Park International’s freshman Fiorente (Monsun).

The Melbourne Cup winner was Victoria’s busiest stallion with 186 mares.  EPI Queensland sire Love Conquers All was the Sunshine State’s most popular horse with 181.

Zoustar followed Fiorente among first-season sires with 185 mares at Widden Stud.  He will transfer to Victoria this year to stand an alternate season at Woodside Park Stud.

Jacqueline Stewart, Keeper of the Australian Stud Book, estimated mares covered during the most recent breeding season would be down 5% to 19,177.  The number of stallions standing in Australia also fell from 621 to an estimated 563.

“I believe the decrease is a marginal in the context of current economic conditions and worldwide trends,” Stewart said.  “The Australian breeding industry is remarkably resilient and the rationalisation in the numbers of stallions and broodmares is not symptomatic of any inherent frailties in the breeding industry.”