A bleeding calf syndrome of unknown cause, resulting in high case fatality rates, has been detected in several European countries. The syndrome, first detected in Germany in 2007, affects calves from two to four weeks of age and has been reported in Belgium, England, France, Germany, Italy, the Netherlands, Scotland, and Wales (ProMED 20091006.3465). The syndrome affects beef and dairy calves of various breeds and crosses.
As of March 2009, more than 100 cases had been reported in Germany (ProMED 20090329.1214). Scotland has reported 40 cases from 20 farms, mostly in beef herds. Thirty-seven cases from 31 farms have been identified in England and Wales, almost exclusively in dairy herds (SAC and Surman). Because blood count changes were detected in asymptomatic calves at affected German farms, researchers concluded in an October 2009 report that the undiagnosed problem may be wider spread than originally thought (Friedrich et al.). Of the asymptomatic calves with blood count changes, some proceeded to develop clinical signs of the bleeding calf syndrome, but others remained clinically asymptomatic.
Two published case studies indicate that mortality ranges from 3 to 5 percent of calves born on an affected farm (SAC and Penny). The case fatality rate is reported as approximately 95 percent (Surman). Antimicrobials, clotting agents, and supportive treatment have been relatively unsuccessful. In one case report, two of three calves that received transfusions died in spite of supportive therapy (SAC). In a media report, a farmer indicated that vitamins and blood-clotting agents were not effective (ProMED 20090329.1214).
Read the full USDA report, including clinical signs, laboratory findings, potential causes and more.