المحاضرة الثانيةInfectious disease

م.م اسعد جاسب العتابيكلية الطب البيطري - جامعة الكوفة

Equine viral Rhinopnemonitis

Mild infectious respiratory disease in young horses characterized by

1)upper respiratory infection in young horses

2)Abortion in mares

3)septicemia and viremia in neonatal foals

4)Nervous signs in adult horses

Etiology

Caused by 4 herpes viruses

1)EHV.4 cause outbreak infection

2 )EHV.1 subtype one cause abortion and subtype 2 cause respiratory signs

3 )EHV.2

4 )EHV.3

1st tow viruses occur in horses and most common

Epidimiology

Disease was reported in many eurepian countries and USA ,in Iraq has not been diagnosed and reported

1

Source of infection

nasal discharge and aborted fetus main source of infection ,the virus can survive outside animal body about 14-45 days

Transmition

1 )Inhalation 2) ingested of contaminated food and water

Pathogenesis

Infection of respiratory tract and proliferation of virus in mucosa

Rhintis and pyrexia

Invasion of virus

Lung pneumonia placenta endometritis

Fetus tissue damage

In placenta cause either still birth or weak then dieه

Clinical signs

There are 4 syndrome associated with the disease in horses

1)upper respiratory infection in young horses

Incubation period 2-20 days, fever but appetite is normal ,congictivitis, Rhinitis serous discharge and cough.

The course of disease 2-5 days ,the disease usually unapparent,in some horses slight enlargement of submandibular L.N and in others diarrhea

and edema

2) Abortion in mares occur during last of pregnancy and no retained placenta

3)septicemia and viremia in neonatal foals

2

The foals normal or weak and may dead about few days

4)Nervous signs in adult horses or paralysis syndrome in adult there is ataxia, paresis, recumbence, and death ,this syndrome occur in outbreak

Complications

The main complications secondary bacterial invasion result in pneumonia

D. Diagnosis

1)strangles

2)catarrhal Rhinitis

3 )Equine viral arteritis

4)Equine influenza

5)purpura hemorrhagica

Diagnosis

1)clinical signs

2)Necropsy and histology

Sever pulmonary congestion, focal hepatic necrosis, intraneuclear inclusion bodies and pneumonia.

3 )Viral isolation from aborted fetus using tissue culture and immunofloracent tech.

4)Serology. By using direct florescent Ab test and Eliza

5)Hematology: Leukopenia

Treatment

There is no specific treatment but adminsteration of antibiotic for 2nd bacterial invasion and treatment should be continuous 4-6 days

3

Control

)Isolation of all infected animals1

2)aborted fetus should be disposed

3)vaccination for suckling foals and mares by using-:

killed vaccine and live attenuated vaccine (hamster adapted and cell culture adapted).

4