Atypical actinobacillosis affecting hind limbs and lungs in a single beef cattle herd

Abstract

Actinobacillosis usually is a sporadic infection that affects the tongue in cattle (“wooden tongue”) with possible spread to the digestive tract. Two 4‐year‐old Rouge‐des‐Prés cows from a single French beef herd were referred for chronic (2‐6 months) swelling and cutaneous nodules in the distal hind limbs. In addition to cutaneous signs, physical examination disclosed cachexia, lameness, lymphadenitis of the hind limbs, and pneumonia in both cows. Cytologic examination of direct skin smears was inconclusive, and no parasites were observed in examination of multiple skin scrapings. Histopathological examination of skin and lung biopsy specimens identified chronic, diffuse, severe pyogranulomatous dermatitis, associated with Splendore‐Hoeppli phenomenon and intralesional Gram‐negative bacteria. Cultures from skin, lymph nodes, and lungs (both cows were euthanized for welfare reasons) identified a Pasteurellaceae organism, confirmed as Actinobacillus lignieresii by partial sequencing of the rpoB gene. This report emphasizes that actinobacillosis can appear as a small outbreak in cattle with cutaneous and respiratory signs.

Actinobacillus lignieresii‐associated myocellulitis of the nasal planum in a Jersey cow

“…Actinobacillosis can be treated with antibiotics but requires prolonged treatment and lesions may regress slowly due to the accompanying fibrosis. Cutaneous actinobacillosis has been successfully treated with procaine dihydrostreptomycin in combination with procaine penicillin or streptomycin for 2–4 weeks 10 or long‐acting oxytetracycline (20 mg/kg intramuscularly, every 72h) for 6 days 3 . Treatment with antibiotics could also have been instituted in the present case, but, due to the advanced stage of the lesion and the reduced milk yield, it was decided to cull the cow.…”

“…Cutaneous actinobacillosis has been successfully treated with procaine dihydrostreptomycin in combination with procaine penicillin or streptomycin for 2-4 weeks 10 or long-acting oxytetracycline (20 mg/kg intramuscularly, every 72h) for 6 days. 3 Treatment with antibiotics could also have been instituted in the present case, but, due to the advanced stage of the lesion and the reduced milk yield, it was decided to cull the cow. Actinobacillosis of the head mostly remains a localised infection and such cases are therefore considered fit for human consumption after condemnation of the affected tissue and the draining lymph nodes.…”

“…In addition to this classical form of actinobacillosis, other manifestations have also been reported, such as oropharyngeal granulomas, infection of the skin and lymphatic system of the limbs, sometimes with distant dissemination to, for example, the lungs, and peritonitis. [1][2][3] Lymphatic actinobacillosis is endemic in some parts of the world. [4][5][6] This manifestation is due to bacterial penetration of the oropharyngeal mucosa with a primary localisation of the bacteria in the lymphatic system causing lymphangitis and lymphadenitis of the head and neck lymph nodes, possibly with extension to adjacent tissues and fistulation to the skin surface.…”

“…The excessive formation of fibrotic connective tissue makes the texture of the tongue firm, giving rise to the common term ‘wooden tongue’. In addition to this classical form of actinobacillosis, other manifestations have also been reported, such as oropharyngeal granulomas, infection of the skin and lymphatic system of the limbs, sometimes with distant dissemination to, for example, the lungs, and peritonitis 1–3 . Lymphatic actinobacillosis is endemic in some parts of the world 4–6 .…”

Actinobacillosis outbreak in cattle with clinical manifestation of hippopotamus-like face

“…In this case, however, the swelling is very firm, and occurring mainly over the scapula and its surroundings, and the histological lesion is characterized by extensive fibrosis in the subcutaneous tissue (Riet-Correa et al 1992). Other diseases such as nocardiosis, which causes pyogranulomatous lesions in the skin and actinomycosis characterized by pyogranulomatous osteomyelitis, especially in the mandible (Relun et al 2019), should also be differentiated from actinobacillosis.…”