Newcastle disease virus in double-crested cormorants in Alabama, Florida, and Mississippi.
In order to understand the epidemiology of Newcastle disease (ND) outbreaks in double-crested cormorants (Phalacrocorax auritus), a study was conducted on wintering migratory cormorants (P. a. auritus) in Alabama and Mississippi (USA) and non-migratory cormorants (P. a. floridanus) that breed in Florida (USA). Antibodies against ND virus were detected by the hemagglutination-inhibition method in sera from 86 of 183 (47%) migratory cormorants over-wintering in eight roosting sites in Alabama and Mississippi between November, 1997 and April, 1999. Titers ranged from 5 to 40. Antibody prevalences in sera collected from females in early winter (November and December) (26%) and late winter (February and March) (56%) were significantly different (P = 0.0007). None of 45 serum samples from 1- to 7-wk-old nestlings from 11 colonies in Florida during the 1997-98 and 1998-99 breeding seasons was positive. However, antibodies were detected in yolk samples from 98 of 126 (78%) eggs collected in these same colonies. Titers ranged from 4 to 256. The prevalence of antibodies in eggs collected from fresh-water colonies (63% prevalence, n = 30) and salt-water colonies (82% prevalence, n = 96) was significantly different (P = 0.041). ND virus was not isolated from tissues of 18 cormorants and cloacal and tracheal swabs from 202 cormorants collected in Alabama and Mississippi; virus was also not isolated from cloacal and tracheal swabs from 51 nestlings from Florida.
Farley
J M
JM
Department of Pathobiology, College of Veterinary Medicine, P.O. Box 110880, University of Florida, Gainesville, Florida 32611, USA.
Romero
C H
CH
Spalding
M G
MG
Avery
M L
ML
Forrester
D J
DJ
D000407:Alabama / Q000453:epidemiology; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D001717:Birds; D004531:Eggs / Q000821:virology; D005260:Female; D005431:Florida / Q000453:epidemiology; D006385:Hemagglutination Inhibition Tests / Q000662:veterinary; D008297:Male; D008922:Mississippi / Q000453:epidemiology; D009521:Newcastle Disease / Q000097:blood / Q000453:epidemiology* / Q000276:immunology; D009522:Newcastle disease virus / Q000276:immunology* / Q000302:isolation & purification; D012621:Seasons; D016036:Seroepidemiologic Studies
D000914:Antibodies, Viral