Ovine Viruses

  1. Border Disease
    4 Syndromes
    • Early embryonic mortality
    • Abortion and stillbirth
    • Congenital malformations
    • Birth of small, weak lambs w/immunosuppression
  2. Border Disease
    Who does it affect?
    • Newborn sheep
    • Congenital infection of BDV during first half of gestation
    • Recovered lambs are PI (congenital/horizontal transmission)
    • Cross species infection (cattle)
    • Pestivirus (like BVDV, Hog cholera; family Flaviviridae)
  3. Border Disease
    Clinical Signs
    • Tremors, ataxia, hairy birth coat, low birth weight, facial bone malformations, short-boxy stature, eye abnormalities
    • No efficacious vaccines
  4. Poxviridae
    • Worldwide
    • Contagious Pustular Dermatitis (Contagious Ecthyma)
    • -Parapoxvirus, 6 serotypes
    • -Milker's nodule/ORF (in humans)
    • Transmitted by direct and indirect contact; suckling lambs
  5. Poxviridae
    Contagious Pustular Dermatitis
    Signs and lesions, Diagnosis
    • Pustular and scabby lesions on muzle and buccal commissures, ears, vulva, prepuce, and lips
    • Systemic signs are rare (gastroenteritis or bronchopneumonia)
    • Diagnosis: clinical signs and/or EM
  6. Poxviridae
    Sheep Pox and Goat Pox Viruses
    Genus, survival, economic importance, etc
    • Genus: Capripox, 1 serotype
    • Survival in scabs for 3 months, contagious
    • Limits trade
    • European breeds more susceptible
    • 50-100% mortality (systemic disease)
    • Only sheep and goats; wild ungulates not affected
  7. Poxviridae
    Sheep and Goat Pox
    Clinical signs/lesions
    • Fever, lacrimation, salivation, nasal discharge
    • Depression and anorexia
    • Eruptions on hairless skin: groin, scrotum, below tail, eyelids, lips, cheeks, nostrils, udder, vulva
    • Swollen LN
    • Macules>papules>pustules>scabs
    • Lambs - malignant form w/high mortality; lesions in oral cavity, digestive, and resp tracts
    • Nodular form: stone pox
  8. Poxviridae
    Sheep and Goat Pox
    • Contagious ecthyma
    • Bluetongue
    • Mycotic dermatitis
    • Sheep scab, Mange, Photosensitization, Peste de petits ruminants
    • Parasitic pneumonia, Caseous lymphadenitis, Insect bites
  9. Poxviridae
    Sheep and Goat Pox
    • Clinical: suspect in animals with characteristic full-thickness skin lesions, fever and lymphadenitis
    • Lab: VI, EM, VN, IFA
    • Histopath: epidermal/epithelial hyperplasia and intracytoplasmic inclusion bodies
  10. Poxviridae
    Sheep and Goat Pox
    Prevention and Control
    • Non-endemic Areas: import restrictions and quarantine
    • Prevent intro of infected animal products (meat, hair, wool, hides)
    • Outbreak in non-endemic area:
    • -quarantine, slaughter infected and exposed, clean and disinfect
    • -ring vaccination
    • No carrier state
    • Isolate infected herds and sick animals for at least 45 days after recovery
    • Vax: live and inactivated
  11. Bluetongue Virus
    Genetics, Serotypes, Transmission, Hosts
    • Family: Reoviridae, genus Orbivirus
    • DS-RNA
    • Closely related to Epizootic hemorrhagic disease virus of deer
    • 24 serotypes worldwide, 6 in US
    • Non-contagious: insect-borne
    • Ruminants - sheep are primary host, can also infect cattle, goats, and deer
    • Lost trade and animal testing
  12. Bluetongue Virus
    • Biting midges (biological vector)
    • -genus Culicoides
    • -principal vector
    • Ticks, sheep keds (mechanical vector)
    • In utero
    • Mechanical
    • Venereal?
  13. Bluetongue Virus
    Clinical Signs in Sheep
    • Incubation: 6-8 days
    • Depression, fever, oral hyperemia
    • Ulcers of lips, gums, dental pad
    • Cyanosis of tongue
    • Coronitis, laminitis
    • Abortions
    • Morbidity 80-100%
    • Mortality 0-50%
  14. Bluetongue Virus
    • Hemorrhages in heart, LN
    • Congenital hypoplasia of cerebellum in aborted lambs
  15. Bluetongue Virus
    • Clinical Signs
    • History
    • -season when insects are active
    • -wasting foot rot
    • Laboratory: VI (do not freeze samples), ELISA, PCR, IFA, VN, serology, complement fixation, examination of proteins (differentiate from related diseases)
Card Set
Ovine Viruses
Ovine Viruses