From third hand information, I gather that these are the Creata/Winner's Choice molds sculpted by Candace Liddy. Circa 1999, Creata stopped producing them (in the middle of "series III"). There apparently was a copyright violation by a company called "Toob". Breyer bought the line (through Candace, bankruptcy?) and began producing them in 2005.
Bay Thoroughbred
Part of the 2005 Breyer Mini Whinnies Mares set. Photo provided by Dorothy Graham.
Chestnut walking Thoroughbred, bay blanket running Appaloosa
Photo provided by Alicia.
Liver Chestnut Ruano Arabian
Part of the 2005 Breyer Mini Whinnies Mares set. Photo provided by Dorothy Graham.
Chestnut Walking Arabian, chestnut rearing Arabian
Photo provided by Alicia.
Chestnut pinto Walking (part) Arabian, dun pinto walking Thoroughbred
Photo provided by Alicia.
Black pinto cutting stock horse
Part of the 2005 Breyer Mini Whinnies Mares set. Photo provided by Dorothy Graham.
Chestnut blanket appaloosa cutting stock horse
Photo provided by Alicia.
Palomino reining stock horse
Part of the 2005 Breyer Mini Whinnies Mares set. Photo provided by Dorothy Graham.
Black pinto American Saddlebred
Part of the 2005 Breyer Mini Whinnies Mares set. Photo provided by Dorothy Graham.
Bay pinto American Quarter Horse
Part of the 2005 Breyer Mini Whinnies Mares set. Photo provided by Dorothy Graham.
Black pinto pulling drafter
Photo provided by Alicia.
Chestnut ruano bay pinto walking Morgan (mold), Golden chestnut pinto prancing Morgan (mold)
Photo provided by Alicia.
Cantering dun (Starlight), standing brown horse (Prancer), black prancing Morgan (Belle)
Image by Breyer. Part of a "Saddle Club" special available in October 2008 (free with purchase of $30+).