a farming systems study of abortion in dairy cattle on the atherton tableland. 2. the pattern of infectious diseases. | the role of infectious agents on dairy farms on the atherton tableland in tropical north queensland was studied as part of a comprehensive investigation into the causes of bovine abortion. the prevalence of antibody in serums collected from 7 herds whose annual abortion rates ranged from 3% to 21% were as follows: leptospira hardjo 49.9% (426/853), l. pomona 0.4% (3/851), bovine virus diarrhoea (bvd) 33.7% (35/104). infectious bovine rhinotracheitis virus (ibr) 11.5% (12/105), akabane virus 92.2 ... | 1989 | 2505741 |