unit 1- equine Neuro diseases

rabies

• occurs through bite of infected animal (bat, raccoon, skunk, fox)

• clinical signs: depends on individual, can be aggressive, can be paralyzed, begins with high fever, hindlimb ataxia, hyperesthesia, death within 3-10 days

• EUTH!

• DX: necropsy, fluoresce the antibodies in the brain tissue

• TX: none

• yearly rabies vx (2ml), booster after exposure if vaccinated and quarantine for 90 days

• ZOONOTIC

viral equine encephalitis

• sleeping sickness

• 4 strains- eastern, western, Venezuelan, west nile

• caused by mosquitos

• all strains are rapidly progressive and highly fatal

• clinical signs for 3: profound depression, fever, ataxia, head pressing, dementia, multiple cranial nerve abnormalaties, sensitivity around head and neck

• west nile signs: weakness, ataxia, muscle fasciculations (muscle twitching), cranial nerve deficits, sensitivity around head and neck

• DX: serology, necropsy, fluoresce of antibodies in brain

• TX: supportive care, hydration, nutrition, clean and dry environment

• there IS a vx for eastern, western, and west nile (2-3 times a year in the south)

• west Nile is ZOONOTIC

equine protozoal myelitits (EPM)

• common cause of neuro diseases in equines

• caused by Sarcocystis neurona (possums)

• infection by fecal-oral transmission

• signs depend on where protozoan goes in the CNS

• clinical signs: ataxia, weakness, muscle atrophy, cranial nerve deficits

• DX: signs, antibodies found in the cerebral spinal fluid

• TX: ponazeril, the sooner the better

herpes (EHV)

• respiratory disease

• can cause abortions, neonatal abnormalaties, and neurologic diseases

• very contagious, spread from nasal secretions (direct or indirect)

• clinical signs: neurologic form causes ascending paralysis of hindlimbs, urinary incontinence, poor tail tone, penile prolapse, recumbency, weakness, incoordiantion

• DX: PCR for the virus

• TX: anti-viral meds, 2-3 months to recover

• EUTH!! never go back to fully normal

wobbler syndrome

• spinal cord disease from compression of the cervical spinal column

• type 1- malformation of vertebrae (6m- 3 y/o)

• type 2- occur in older horses due to arthritic changes

• males are x4 more likely, thoroughbreds more common

• clinical signs: ataxia of hindlimbs, symmetric incoordination

• DX: rads, myelography

• TX: sx

botulism

• rapidly progressive, fatal

• caused by chlostridium botulinum- neurotoxin, or infected wounds or contaminated feed

• states like PA, OH, and KY

• clinical signs: profound weakness, muscle twitches, dysphagia, death

• DX: PE, rule out other diseases

• TX: supportive care, EUTH!

• vx in endemic areas

tetanus

• highly fatal

• caused by chlostridium tetani

• invades wounds or cuts

• clinical signs: stiff gait, hyperexcitability, seizure, coma, death

• DX: rule out other diseases

• TX: tetanus anti-toxin, tetanus toxoid vx given annually