2022 Kidding Schedule
Please complete the goat request form to be added to a doe's wish list or to make a reservation.
*May be offered for sale after kidding - please complete the Goat Request Form to be added to the waitlist.
Pricing Calculator
Prices shown are based on the backup buck selection and will be adjusted should does be confirmed pregnant by AI.
Breed Development and Inbreeding
First, all domestic animals have been subject to inbreeding during the period of breed formation. Nigerian Dwarf goats were developed from small goats imported from Africa between the 1930s and 1950s. These were primarily zoo animals per the Livestock Conservancy. Nigerian Dwarf goats were first recognized as a breed by the American Goat Society in 1981. The American Dairy Goat Association did not recognize the breed, by creating a purebred herdbook, until 2005.
There are genetic consequences when forming breeds (inbreeding for specific traits). The most obvious one is the loss of genetic diversity. With inbreeding comes the unintended consequence of an increase in deleterious alleles (variant form of a gene). During breed formation, the priority and focus is selection for breed traits such as stature and milk production. Disease-producing recessive alleles start becoming visible as the breed becomes more homozygous (uniform), those alleles spread throughout the breed, and are ultimately paired to produce the genetic defect, such as carpal hyperextension and split teats.
The next key step in breed development is the active monitoring and selection against genetic disease. Research on dog breeds is far more advanced than in goats. The Australian Shepherd Health & Genetics Institute provides their community with information on genetic databases, disease prevalence, and disease testing. Reputable dog breeders screen their dogs using DNA testing.
As the population of a breed expands to ten generations, inbreeding coefficients and the risk of accidentally pairing deleterious recessive alleles declines. In addition, active monitoring and selection for quality and health helps to purge developing breeds of genetic disease.
Popular sire syndrome moves a breed in the other direction as that sire's lines appear in increasing numbers of pedigrees and push inbreeding coefficients beyond healthy levels. Consequences of inbreeding to concentrate that sire's (or dam's) influence are the increase in genetic load (recessive deleterious alleles) and inbreeding depression (e.g., milk depression).
There are genetic consequences when forming breeds (inbreeding for specific traits). The most obvious one is the loss of genetic diversity. With inbreeding comes the unintended consequence of an increase in deleterious alleles (variant form of a gene). During breed formation, the priority and focus is selection for breed traits such as stature and milk production. Disease-producing recessive alleles start becoming visible as the breed becomes more homozygous (uniform), those alleles spread throughout the breed, and are ultimately paired to produce the genetic defect, such as carpal hyperextension and split teats.
The next key step in breed development is the active monitoring and selection against genetic disease. Research on dog breeds is far more advanced than in goats. The Australian Shepherd Health & Genetics Institute provides their community with information on genetic databases, disease prevalence, and disease testing. Reputable dog breeders screen their dogs using DNA testing.
As the population of a breed expands to ten generations, inbreeding coefficients and the risk of accidentally pairing deleterious recessive alleles declines. In addition, active monitoring and selection for quality and health helps to purge developing breeds of genetic disease.
Popular sire syndrome moves a breed in the other direction as that sire's lines appear in increasing numbers of pedigrees and push inbreeding coefficients beyond healthy levels. Consequences of inbreeding to concentrate that sire's (or dam's) influence are the increase in genetic load (recessive deleterious alleles) and inbreeding depression (e.g., milk depression).
About Inbreeding Coefficients (COIs)
Two common breeding practices are inbreeding and outcrossing. Inbreeding is practiced industry-wide with Nigerian goats. It is not unusual to find animals with Coefficients of Inbreeding (COIs)* as high as 30%-60%. Tracking COIs can be challenging in Nigerians as ADGA Genetics is often missing pedigree data for the breed and thus reports inaccurately low COIs on individual animals.
Inbreeding coefficients are a measure of the increased percentage in homozygous (same) gene pairs in an individual in comparison to the breed average. A goat that is inbred is "more likely to have identical gene pairs, so is more likely to express undesirable characteristics from recessive genes, leading to a decline in performance called inbreeding depression" (Shepard, "Practical Genetics for Dairy Goat Breeding," http://certification.goats.langston.edu/login/index.php, p. 293.).
Depending on the source, the recommended ceiling should be somewhere between 5% and 12.5% after all generations are considered.
Depending on the source, the recommended ceiling should be somewhere between 5% and 12.5% after all generations are considered.
OutcrossingOutcrossing is often used to bring new, desirable traits into a herd or to increase vigor. It increases genetic diversity and thus reduces the likelihood of the resulting individual being subject to disease or genetic abnormalities. Defects may still occur if animals are not carefully screened in advance as outcrossing won't necessarily correct existing genetic flaws.
A disadvantage of outcrossing is that the outcomes are less predictable. Moreover, it may increase the time required to achieve your goals as a breeder. An example of an exceptional outcross is SGCH Dill's XM Keena 4*M EX92 (EEEE), an ADGA Reserve National Champion Doe. |
InbreedingInbreeding is practiced in order to improve predictability of certain traits. For example, to try to ensure that all offspring have strong medial suspensory ligaments.
A disadvantage of inbreeding is that both good and bad traits are transmitted when genetics become concentrated through inbreeding. In addition, inbred animals have been found to be less vigorous. This extends to milk production. In dairy cattle research has found that milk depression begins at 12.5%. Linebreeding (a term sometimes used for lower levels of inbreeding) can produce exceptional animals such as Dill's GA Whiskey Lullaby 4*M EX91 (EEEE) at 14% and SGCH Castle Rock Owl's Clover EX90 (VEEE) at 12%. |
For more information about inbreeding coefficients:
www.instituteofcaninebiology.org/blog/coi-faqs-understanding-the-coefficient-of-inbreeding
www.instituteofcaninebiology.org/blog/coi-faqs-understanding-the-coefficient-of-inbreeding
Langston University Certificated Farm
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