Herd risk factors for serological evidence of Aujeszky's disease virus infection of breeding sows in northern Germany (1990-1991).
The distribution of herd risk factors with respect to serological evidence of Aujeszky's disease virus (ADV) infection in breeding sows was studied using samples collected in the early phase of an area-wide eradication programme in two districts of Northern Germany (Schleswig-Flensburg and Nordfriesland). The odds of seropositivity in breeding females were 6.5-times higher for herds that purchased replacement gilts compared with herds that introduced gilts from their own inventory. Herds in which confirmed clinical Aujeszky's disease (AD) had occurred during the 1980s had 4.2-times higher odds of seropositive test results compared with herds without clinical outbreaks of AD. The log-odds of a herd having seropositive females increased, in a curvilinear pattern, with increasing herd size. The slope of the log-transformed herd-size line suggested that wind-borne transmission may have been an important route for among-herd transmission of ADV. It was concluded that, in areas with endemically-infected swine herds, the expected level of ADV infection will be highest in regions with large herds and previous clinical outbreaks of AD. This should be taken into account in the design of future area-wide AD-eradication campaigns.
Leontides
L
L
Department of Animal Science and Animal Health, Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
Ewald
C
C
Willeberg
P
P
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D016022:Case-Control Studies; D005260:Female; D005858:Germany / Q000453:epidemiology; D011558:Herpesvirus 1, Suid / Q000276:immunology*; D016017:Odds Ratio; D011557:Pseudorabies / Q000453:epidemiology*; D012044:Regression Analysis; D012307:Risk Factors; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology*
D000914:Antibodies, Viral