Nikki Fideldy (Student Name)
Livestock Production 220 (Class Name)
Benjamin Williams (Teacher Name)
February 1, 2011 (Due Date)
Neuropathic Hydrocephalus (NH)
About two years ago, June 12, 2009, Neuropathic Hydrocephalus was recognized as a
genetic defect. Neuropathic Hydrocephalus,
also referred to as “water head”, is a lethal
genetic defect in Black Angus cattle. Calves
will have 25-35 pound birth weights with
evidence that points toward early abortions
due to the defect. The skull is extremely
enlarged and has been known to be
volleyball to basketball sized. The American
Angus Association explains that “the bones
of the skull are malformed and appear as
loosely organized bony plates that fall apart
when the cavity is opened”. Research has
found that the cranial cavity is filled with
fluid but no recognizable brain tissue is
evident. While looking at the spinal canal, researches noticed it to be dilated with no observable
spinal tissue evident.
A (normal)
A (normal)
NH is a result of a recessive
A (normal)
AA (Free/non- AA (free/nonmutation on a single cattle chromosome.
carrier)
carrier)
Cattle who exhibit NH will be homozygous
a (recessive
Aa (carrier)
Aa (carrier)
for the mutated gene. An Angus or Angusdefect)
cross cow, heifer, bull or steer that has the
recessive NH mutation is known as a NH carrier. One major problem is a NH carrier looks
perfectly normal. There is no way you can identify an
animal as a NH carrier by its looks.
Thankfully there are testing procedures that
identify NH carriers. “The type of DNA sample required
to perform the test varies from lab to lab but includes; hair
root samples, blood-spot or FTA cards, whole blood in
“purple-top” tubes, tissue samples from ears and semen
samples” (American Angus Association, November
2010). One NH testing laboratory approved by the
American Angus Association is Pfizer Animal Genetics.
Pfizer Animal Genetics is a business unit of Pfizer Animal
Health, a world leader in discovering and developing innovative animal vaccines and
prescription medicines making Pfizer Inc. the world’s largest research-based pharmaceutical
company. Nigel Evans, Vice President of Animal Genetics, says “by collaborating with industry
partners, we are able to offer NH-defect testing and can work with producers to help reduce the
impact of this genetic defect”.
Works Cited
American Angus Association. The American Angus Association, 2011. Web. 25, Jan. 2011.
Pfizer Inc. Pfizer Animal Genetics, 2009. Web. 25, Jan. 2011.