By a process of elimination, the only subject left to discuss is mixed-sex inbreeding (male-female or female-male). An example is Union Rags. I have already discussed his 3×4 male-male duplication to Northern Dancer.
He is also 4×3 to Mr. Prospector and 5×5 to Native Dancer. The former is though a female on top (She’s a Talent as the second dam of Dixie Union) and a male on the bottom (Gone West as the broodmare sire). The latter is also through a female on top (Natalma as the dam of Northern Dancer) and a male on bottom (Raise a Native as the sire of Mr. Prospector).
For the sake of this discussion multiple inbreeding is not counted. Mixed-sex inbreeding is either through a male on top (sire’s side of the pedigree) and a female on bottom (dam’s side of pedigree) or vice versa, female on top (sire’s side of pedigree) and male on bottom (dam’s side of pedigree). Some people also refer to this as balanced-sex inbreeding.
As usual, some pretty good stakes winners are inbred in this fashion, most of them to Mr. Prospector. The following stakes winners are inbred male-female to Mr. Prospector:
Roman Ruler (2,521 Performance Points, Fusaichi Pegasus–Silvery Swan, Silver Deputy, 2×4 through Fusaichi Pegasus and Silver Valley, sold for $500,000 as a yearling in 2003).
Diabolical (2,467, Artax–Bonnie Byerly, Dayjur, 4×4 through Conquistador Cielo and Gold Beauty, sold for $62,000 as a yearling in 2004 and $300,000 as a two-year-old in 2005).
Capt. Candyman Can (2,192, Candy Ride–Stormy Way, Storm Creek, 5×4 through Fappiano and Shawnee Creek, sold for $25,000 as a yearling in 2007).
Miraculous Miss (2,032, Mr. Greeley–No Small Miracle, Silver Deputy, 3×4 through Gone West and Silver Valley, sold for $65,000 as a yearling in 2004 and $350,000 as a two-year-old in 2005).
The following stakes winners are inbred female-male to Mr. Prospector:
Awesome Gem (4,451, Awesome Again–Piano, Pentelicus, 4×4 through Prime Prospect and Fappiano, sold for $150,000 as a yearling in 2004 and $150,000 as a two-year-old in 2005).
Kodiak Kowboy (4,063, Posse–Kokadrie, Coronado’s Quest, 4×4 through Silver Valley and Forty Niner, sold for $40,000 as a weanling in 2005 and $70,000 as a yearling in 2006).
General Quarters (2,227, Sky Mesa–Ecology, Unbridled’s Song, 4×5 through Preach and Fappiano, sold for $20,000 as a yearling in 2007),
Rail Trip (2,234, Jump Start–Sweet Trip, Carson City, 4×3 through Hopespringsforever and Carson City, sold for $200,000 as a yearling in 2006).
Dakota Phone (2,083, Zavata–World of Gold, Spinning Gold, 5×4 through She’s a Talent and Fast Gold, sold for $67,000 as a two-year-old in 2007).
The following stakes winners are inbred to Northern Dancer, the first two male-female and Flat Out female-male:
Informed Decision (5,014, Monarchos–Palangana, His Majesty, 4×3 through Dixieland Band and Countess North, sold for $150,000 as a yearling in 2006 and $320,000 as a two-year-old in 2007).
Spaghetti Mouse (2,154, Archers Bay–Desert Mouse, With Approval, 5×5 through Vice Regent and Cool Mood, sold for $15,372 as a yearling in 2003).
Flat Out (2,112, Flatter–Cresta Lil, Cresta Rider, 4×3 through Wild Applause and Cresta Rider, sold for $11,000 as a weanling in 2006 and $85,000 as a yearling in 2007).
Among the four sires I surveyed (Northern Dancer, Mr. Prospector, Hail to Reason, and Secretariat), 6,199 sales foals of 2003-2007 were inbred in this mixed-sex fashion. That is about 8.8% of all 70,714 foals.
Those 6,199 foals were not cheap. They sold for a gross of $407,973,062, an average of $65,813 (compared to the overall average of $54,140), a maverage of 182.98 (compared to the overall maverage of 163.11), and a Price Index of 1.12.
A total of 256 stakes winners (including the dozen listed above) were included in these 6,199 foals. That is 4.13%, well above the overall figure of 3.4%. However, those 256 stakes winners averaged only 580 Performance Points apiece, below the overall average of 610.
So taking both quantity and quality of stakes winners into account, these 6,199 foals had a PPI (result) of 1.16 (1.1551, to be precise), just slightly above their Price Index of 1.12. So they sold for prices about 12% above average and produced results about 15.5% above average, a slightly positive result.
Female-male predominated over male-female, with 3,411 foals of the former persuasion and 2,788 foals of the latter persuasion. The latter was more expensive than the former. The 2,788 male-female foals sold for a gross of $200,966,012, an average of $72,083, a maverage of 190.51, and a Price Index of 1.17. The 3,411 female-male foals sold for a gross of $207,007,050, an average of $60,688, a maverage of 176.83, and a Price Index of 1.08.
The two groups were very close in terms of absolute results. Male-female had 119 stakes winners from 2,788 foals (4.27%), averaging 564 Performance Points apiece, for a PPI (result) of 1.16. Female-male had 137 stakes winners from 3,411 foals (4.02%), averaging 601 Performance Points apiece, for a PPI (result) of 1.15.
So male-female sold for prices about 17% above average and achieved results about 16% above average, a very slightly negative result. Female-male sold for prices about 8% above average and achieved results about 15% above average, a slightly more positive result.
Here are the individual results for the four sires in abbreviated fashion:
Sire Foals Price Index PPI (result)
Northern Dancer 2,829 0.96 0.91
Mr. Prospector 2,210 1.35 1.69
Hail to Reason 834 1.11 0.77
Secretariat 326 1.02 0.60
So Mr. Prospector had pretty good results (Price Index of 1.35 and PPI of 1.69). Northern Dancer was slightly negative (Price Index of 0.96 and PPI of 0.91). Hail to Reason was worse than Northern Dancer (Price Index of 1.11 and PPI of 0.77). Secretariat was worse than Hail to Reason (Price Index of 1.02 and PPI of 0.60). Note that not one of the dozen best stakes winners in this group listed above was inbred to Hail to Reason or Secretariat.
So it is difficult to assess mixed-sex inbreeding as an overall proposition. As usual, it depends on the sire. Also as usual, with an overall Price Index of 1.12 and PPI of 1.151, you get pretty much what you pay for, as the old expression goes.