Cancer Study Seeks Participants
The University of California at Davis seeks participants for a planned study on squamous cell carcinoma in the Nigerian Dwarf. Squamous is very common in Nigerians and typically appears in light-pigmented animals in the perineal area under the tail. As a result it is sometimes referred to as “tailfold cancer” or “under-the-tail cancer.”
Perineal squamous is believed to be caused by an accumulation of ultraviolet damage. Animals are generally between the ages of 4 and 9 years old when the cancer first appears as it takes a certain amount of time for the damage to become cancerous. However it is not unheard of for Nigerians to develop squamous at age 3 and even younger. UV damage is most harsh when the animal has unpigmented skin; pigment protects the skin from damage, and squamous is unlikely (but not impossible) in animals with black or fully pigmented tails.
Haflinger, Belgian, and paint horses, as well as Hereford cattle and a number of other cattle breeds, have an apparent genetic predisposition to squamous. In Haflingers the predisposition to cancer (ocular squamous) has been shown to be strongly linked to a missense mutation identified by UC-Davis. This mutation interferes with the horse’s ability to repair UV-damage. UC-Davis developed a test for this mutation, which is recessive. That test enables breeders to identify carrier and affected horses and to prevent subsequent generations from receiving two copies of the affected gene. In affected Haflingers with the mutation, ocular SCC appears at a younger age than in the general population.
Very little research on squamous has been done in goats but in one of the few academic studies, research suggested a predisposition to squamous in dwarf goats (Nigerians, specifically.) Four of the nine goats in the study were Nigerian. Another goat was a pygmy (the Nigerian breed branched off from the pygmy breed in the 1980s) and three were “Tennessee Meat” goats. The Tennessee meat goat is a trademarked fullblooded myotonic (aka fainting) goat developed for its heavy muscling by Onion Creek Ranch.
The Nigerian Dwarf is believed to have incorporated myotonic genetics into the breed in the past. The Nigerian, the Fainting Goat (myotonic) and the Angora are the only breeds with blue eyes.