Bovine respiratory syncytial virus seroprevalence and risk factors in endemic dairy cattle herds.
The herd seroprevalence of bovine respiratory syncytial virus (BRSV) was studied in 59 dairy cattle herds using serology on random selected animals stratified by two age classes (heifers, cows). Risk factors for primary infections in heifers were investigated using a questionnaire on management conditions and data on bovine viral diarrhoea (BVD) status. At least one seropositive cow was present in all the herds. In 25% of the herds all individual were seropositive and 22% of herds had all heifers seronegative. Analysis of the influence of risk factors retained summer pasture and BVD status. In particular, absence of summer pasture and the BVD positive status of heifers were associated with an increased risk of BRSV infection in heifers group.
Luzzago
Camilla
C
Università degli Studi di Milano, Dipartimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Via Celoria 10, 20133, Milano, Italia. camilla.luzzago@unimi.it
Bronzo
Valerio
V
Salvetti
Stefano
S
Frigerio
Michela
M
Ferrari
Nicola
N
D000367:Age Factors; D000818:Animals; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000150:complications / Q000453:epidemiology; D002417:Cattle; D003612:Dairying; D005260:Female; D030243:Hemorrhagic Syndrome, Bovine / Q000150:complications / Q000453:epidemiology; D018357:Respiratory Syncytial Virus Infections / Q000453:epidemiology / Q000209:etiology / Q000662:veterinary*; D018112:Respiratory Syncytial Virus, Bovine / Q000276:immunology*; D012307:Risk Factors; D016036:Seroepidemiologic Studies