Assié S, Seegers H, Makoschey B, Désiré-Bousquié L, Bareille N
UMR 1300 Unit of Bio-aggression, Epidemiology and Risk Analysis, Veterinary School, INRA, BP 40706, F-44307, Nantes, Cedex 03, France.
Vet Rec. 2009 Aug 15;165(7):195-9. doi: 10.1136/vr.165.7.195.
The incidence of clinical respiratory disease in 698 young beef bulls kept in 68 pens, and their exposure to respiratory pathogens after their arrival at 51 fattening operations in western France were assessed. Antibodies against bovine respiratory syncytial virus (BRSV), bovine herpesvirus type 1 (BHV-1), Mannheimia haemolytica and Mycoplasma bovis were measured by ELISA. The incidence risk of respiratory disease was 18.5 per cent during the first six weeks. Cases occurred in 37 of the 68 pens, and in these pens 30.9 per cent of the bulls were affected. Their exposure to BHV-1 was very limited. When they arrived a high proportion of the bulls were seropositive to M haemolytica and a high proportion seroconverted to BRSV, M haemolytica and M bovis within the first six weeks. The risk of incidence of respiratory disease was lower in the pens in which the bulls had been vaccinated against M haemolytica. Higher proportions of the bulls were affected in pens in which small proportions of the bulls were seropositive to M haemolytica or BRSV on arrival, and in pens in which high proportions of the bulls were exposed to M haemolytica or BRSV during the first six weeks.
对饲养在68个栏中的698头年轻肉用公牛的临床呼吸道疾病发病率，以及它们抵达法国西部51个育肥场后接触呼吸道病原体的情况进行了评估。通过酶联免疫吸附测定法（ELISA）检测了针对牛呼吸道合胞病毒（BRSV）、牛疱疹病毒1型（BHV - 1）、溶血曼氏杆菌和牛支原体的抗体。在前六周，呼吸道疾病的发病风险为18.5%。68个栏中有37个栏出现了病例，在这些栏中，30.9%的公牛受到影响。它们接触BHV - 1的情况非常有限。到达时，很大比例的公牛对溶血曼氏杆菌血清呈阳性，并且很大比例的公牛在头六周内血清转化为对BRSV、溶血曼氏杆菌和牛支原体呈阳性。在已接种抗溶血曼氏杆菌疫苗的栏中，呼吸道疾病的发病风险较低。在到达时对溶血曼氏杆菌或BRSV血清呈阳性的公牛比例较小的栏中，以及在头六周内很大比例的公牛接触过溶血曼氏杆菌或BRSV的栏中，受影响的公牛比例较高。
