Читать книгу Raising Goats For Dummies - Cheryl K. Smith - Страница 63

The G-6-S gene mutation was first discovered in 1987. Further investigation showed that about 25 percent of Nubians carry the gene, which results from a single mutation. It affects only Nubians and Nubian crosses. Carriers (N/G genotype) aren’t affected but can transmit the gene to 50 percent of their offspring. Carriers can make great pets, packers, and brush control goats.

Goats with the gene mutation lack the enzyme G-6-S, which causes a variety of symptoms that vary in severity. Failure to grow is the main sign. In some cases, a kid starts out smaller than normal and continues to grow slowly; in others a kid grows normally for three months or so and then stops growing. Other goats seem to grow to a normal size but are found to actually be small in comparison to other goats in that bloodline. Other signs include a lack of muscle mass, a “slab-sided” appearance or a “blocky” head. They seem to have compromised immune systems, experience reproductive problems and, in some cases, become deaf or blind. The longest a goat with G-6-S has been known to survive is less than four years. Death is usually caused by heart failure. Because goats with this defect can live long enough to breed, they continue to pass on the gene. Many Nubian breeders now test all breeding stock for the defect.