ACTINOBACILLOSIS is a well-recognised clinical entity in cattle caused by Actinobacillus lignieresii , manifesting as a chronic pyogranulomatous inflammatory condition usually involving the tongue (wooden tongue), skin (cutaneous form), regional lymph nodes and less frequently the oesophagus, rumen and reticulum (Ryecroft and Garside 2000, Milne and others 2001, Brown and others 2007). It has been rarely recorded as a postoperative complication of caesarean section (de Kruif and others 1992). There are a small number of reports of respiratory-tract involvement including the nares, the nasal cavity, nasopharynx, trachea and lungs (Gorrie 1961, Carbonell 1976, Bertone and Rebhun 1984, Rebhun and others 1988, Brown and others 2007, Angelo and others 2009). This short communication describes a small outbreak of actinobacillosis in adult suckler cows presenting primarily with respiratory signs in the UK. The herd was an organic 100 cow beef suckler unit of Stabiliser and Stabiliser cross cows with a conventional system of management. The first cases were seen in July and September 2010 involving two adult cows. In January/February 2011, a third cow and a bulling heifer were similarly affected. Clinical signs in order of appearance were stertorous respiratory noise, nasal discharge (blood, pus and/or clear mucus), excess salivation, parotid lymph node swelling, submandibular oedema, clear ocular discharge, tongue rolling and excessive …