Understanding the language of equine pedigrees is crucial for anyone involved in breeding, purchasing, or researching horses. This terminology, while sometimes nuanced, provides a clear framework for tracing lineage and understanding genetic influence. This guide breaks down essential terms, clarifying their meaning and application in the world of horse ancestry.
Key Pedigree Terms and Their Meanings
The terminology used in pedigree analysis can seem complex, but it’s built upon logical relationships. Here’s a breakdown of fundamental terms:
- Sire and Dam: In equine lineage, the sire is the father, and the dam is the mother.
- To Produce vs. To sire: A mare (female horse) produces foals, while a stallion (male horse) sires foals. Stallions do not “produce” offspring.
- Out of and By: A horse is always described as being out of its dam (mother) and by its sire (father). For example, a horse named “Hollywood Dun It” is by “Hollywood Jac 86” (his sire) and out of “Blossom Berry” (his dam).
- Half-sister or Half-brother: This designation applies only to horses that share the same dam (mother). Horses that share the same sire but have different dams are not considered half-siblings in pedigree terms.
- Brother or Sister: When used in a pedigree, “brother” or “sister” signifies a full sibling, meaning the horses share both the same sire and dam. For instance, stating “Dry Doc, brother to Doc O’Lena” confirms they are full biological brothers.
- Broodmare Sire or Dam’s Sire: This refers to the sire of a horse’s dam, making them the horse’s maternal grandfather.
- Tail Male Line: This traces a horse’s male ancestry exclusively through its sire. For example, the tail male line of “Hollywood Dun It” would be listed as: Hollywood Dun It, by Hollywood Jac 86, by Easter King, by King, by Zantanon, by Little Joe, by Traveler.
- Tail Female Line: This traces a horse’s female ancestry exclusively through its dam. For example, the tail female line of “Hollywood Dun It” would be listed as: Hollywood Dun It, out of Blossom Berry, out of Regina Bella, out of Tina Regina, out of Little Dunny 2, out of Anna’s Little Dunny, out of Anna Wilkens.
- First Dam, Second Dam, Third Dam, etc.: The first dam is the horse’s mother. The second dam is the mother of the horse’s dam (maternal grandmother). The third dam is the mother of the second dam (maternal great-grandmother), and so on. This always refers to the tail female line.
- Top Side: This is informal terminology for the sire’s side of a pedigree chart.
- Bottom Side: This is informal terminology for the dam’s side of a pedigree chart.
- Blue Hen: This term describes a mare that has had a significant and enduring, multi-generational impact on a breed, often through both male and female descendants. Notable examples in the Quarter Horse breed include “Royal Blue Boon” in cutting disciplines and “Do Good” in racing.
Understanding Breeding Practices
Beyond basic lineage, specific terms describe breeding strategies and their outcomes:
- Inbreeding: This involves breeding closely related individuals.
- Inbreeding Quotient: This is a numerical representation of how often a specific horse appears in a horse’s pedigree. In a genetic pedigree, the first generation comprises the sire and dam. For example, if “Leo” is described as “2×2 to Joe Reed,” it means “Joe Reed P-3” appears twice in Leo’s second generation (grandparents). Leo’s sire is by “Joe Reed P-3,” and Leo’s dam is also by “Joe Reed P-3.” Learn more about linebreeding here.
- Linebreeding: This refers to breeding individuals that are distantly related, typically ancestors beyond the fourth generation.
- Outcross: This is the breeding of two unrelated individuals or individuals whose common ancestor is many generations back in their pedigrees. Learn more about outcrosses and hybrid vigor here.
- Nick: A “nick” occurs when specific bloodlines consistently produce outstanding performers when crossed together. These successful crosses often persist through several generations, where a stallion’s sons and grandsons may perform well with another stallion’s daughters and granddaughters. Learn more about nicking here.
Reading a Pedigree Chart
Pedigree charts are conventionally structured to present information clearly. A common format, such as “Freightrain B-Sinuous by Mr Jess Perry,” indicates the sire (“Freightrain B”), the dam (“Sinuous”), and the dam’s sire (“Mr Jess Perry”). Remember that a horse is “by” its sire and “out of” its dam. In Quarter Horse pedigrees, the sire’s lineage is typically displayed at the top, and the dam’s lineage at the bottom. The pedigree reads from left to right, with each successive generation branching outward. The dam’s mother is known as the second dam, and her mother is the third dam, and so forth.
For comprehensive pedigree information, the American Quarter Horse Association offers free pedigree records. Additionally, detailed pedigree research reports from QData are available.
