"She's a good doer and we've got her on a good diet and she only has to smell food and she puts weight on but she's looking good."
Werrett said Black Caviar's owners would spend the next few weeks planning her 2014 mating partner.
Connections have engaged breeding experts to assist them with their decision, which Werrett said would be a choice of Australia's top stallions.
"She could go to More Than Ready, go back to Exceed And Excel, go to Snitzel, High Chaparral is in the mix and there's one other," Werrett said.
Belle Couture will join her illustrious half-sister at stud this season following the retirement of the $2.6 million yearling after just four starts.
Belle Couture won a maiden at Caulfield on Easter Monday before injury hampered her in her final two runs at Flemington in May, prompting the early end to the 3-year-old's racing career.
- AAP