Occurrence of Nervous Coccidiosis in Calves
No CommentsNervous coccidiosis is one of several neurological syndromes
that can occur in young calves. Normally
calves that exhibit clinical enteric coccidiosis may experience this
neurological syndrome (Hauptmeier, L. D., Iowa Beef Center Report, April 1997).
As with enteric coccidiosis, the nervous coccidiosis form
appears most often in fall and early winter when calves are stressed due to
weaning, comingling, shipping, etc. To
our knowledge, research scientists have not been able to experimentally
reproduce this syndrome.
Clinical signs of nervous coccidiosis vary widely. Some calves may show slight muscle incoordination
while others may have continuous seizures.
Some calves may get up and appear normal between seizures. Stress or handling will often trigger the
reoccurrence of seizures. The diagnosis of nervous coccidiosis can be confirmed
by finding the aberrant oocyst in a cross section of the spinal cord.
The condition is a result of the oocysts moving from their
normal habitat in the intestine and migrating into the spinal cord. The varied neurological conditions observed
depend on what area of the spinal cord the oocysts invade.
Nervous coccidiosis is most often associated with enteric
coccidiosis but you may not see the classical signs of coccidiosis which
include loose stools, bloody diarrhea, etc.
The mortality rate of nervous coccidiosis can be as high as 90%.
The most logical approach to prevent nervous coccidiosis is
the prevention of all coccidiosis through good management practices outlined in
www.coccidiosistreatment.com and starting all calves on a coccidiostat such as
Rumensin® when calves are started on feed.

