The following information is taken from the website of UC Davis Veterinary Medicine / Veterinary Genetics Lab
Congenital myotonia, characteristic of Fainting Goats, is an heritable neuromuscular disorder characterized by a slow relaxation of skeletal muscles following voluntary contraction. The sudden muscle stiffness often causes the animal to fall over briefly.
Phenotype: Affected goats become stiff and immobile, and often fall over briefly, following sudden forceful movements or when startled.
Mode of Inheritance: Autosomal recessive
Alleles: N = Normal, CM = Myotonia Congenita
Breeds appropriate for testing: Myotonic or Tennessee Fainting Goat and their crosses, Nigerian Dwarf Goat
Explanation of results:
• Goats with N/N genotype will not have this inherited form of neuromuscular disorder and cannot transmit this allele to their offspring.
• Goats with N/CM genotype will not be affected by this inherited form of neuromuscular disorder but are carriers . They may transmit this allele to 50% of their offspring. Matings between two carriers are predicted to produce 25% of affected goats.
• Goats with CM/CM genotype are expected to develop this form of neuromuscular disorder and will transmit this allele to all of their offspring.
Congenital myotonia, characteristic of Fainting Goats, is an heritable neuromuscular disorder characterized by a slow relaxation of skeletal muscles following voluntary contraction. The sudden muscle stiffness often causes the animal to fall over briefly.
Phenotype: Affected goats become stiff and immobile, and often fall over briefly, following sudden forceful movements or when startled.
Mode of Inheritance: Autosomal recessive
Alleles: N = Normal, CM = Myotonia Congenita
Breeds appropriate for testing: Myotonic or Tennessee Fainting Goat and their crosses, Nigerian Dwarf Goat
Explanation of results:
• Goats with N/N genotype will not have this inherited form of neuromuscular disorder and cannot transmit this allele to their offspring.
• Goats with N/CM genotype will not be affected by this inherited form of neuromuscular disorder but are carriers . They may transmit this allele to 50% of their offspring. Matings between two carriers are predicted to produce 25% of affected goats.
• Goats with CM/CM genotype are expected to develop this form of neuromuscular disorder and will transmit this allele to all of their offspring.
A DNA test for Congenital Myotonia became available through UC Davis's Veterinary Diagnostics Laboratory in the fall of 2025, and this inherited disorder was subsequently confirmed in a Nigerian Dwarf doe in Florida who was exhibiting signs of myotonia. She has the CM/CM genotype.
Because of this one doe and her CM/CM status, congenital myotonia quickly became a hot topic for Nigerian Dwarf breeders. Social media was filled with rumors of suspected carriers that resulted in a testing frenzy. CM testing is performed by UC Davis Veterinary Diagnostics Laboratory in California (accredited) and GenSol Diagnostics in Georgia (not accredited).
It is important to note that it has been known that myotonic goats were in the blending of breeds/genetics that contributed to what ultimately became the "purebred" Nigerian Dwarf goat, therefore, finding congenital myotonia carriers in Nigerian Dwarf goats was not surprising.
The goal of some breeders is to breed negative (N/N) does to negative (N/N) bucks, thereby eliminating the possibility of producing a carrier. Other breeders, who do not wish to cull an otherwise valuable animal, plan to breed carriers to negative animals and to test offspring to determine their status before moving them on into breeding programs.
While we have never seen signs of myotonia in any goats in our herd, as we test our animals, their results will be viewable on this page.
We will be doing our testing through UC Davis Veterinary Diagnostics Laboratory.
Because of this one doe and her CM/CM status, congenital myotonia quickly became a hot topic for Nigerian Dwarf breeders. Social media was filled with rumors of suspected carriers that resulted in a testing frenzy. CM testing is performed by UC Davis Veterinary Diagnostics Laboratory in California (accredited) and GenSol Diagnostics in Georgia (not accredited).
It is important to note that it has been known that myotonic goats were in the blending of breeds/genetics that contributed to what ultimately became the "purebred" Nigerian Dwarf goat, therefore, finding congenital myotonia carriers in Nigerian Dwarf goats was not surprising.
The goal of some breeders is to breed negative (N/N) does to negative (N/N) bucks, thereby eliminating the possibility of producing a carrier. Other breeders, who do not wish to cull an otherwise valuable animal, plan to breed carriers to negative animals and to test offspring to determine their status before moving them on into breeding programs.
While we have never seen signs of myotonia in any goats in our herd, as we test our animals, their results will be viewable on this page.
We will be doing our testing through UC Davis Veterinary Diagnostics Laboratory.
OLD MOUNTAIN FARM RENNY QUINN
https://geneticstest.adga.org/PedigreePrint.aspx?RegNumber=D002448487
CASA RAM WS GOLDEN TRAVELER
