A review of cardiac blackleg in cattle, and report of 2 cases without skeletal muscle involvement in Argentina

Abstract

Blackleg is an infectious disease caused by Clostridium chauvoei. Cardiac blackleg has been reported in ruminants as an uncommon presentation of the disease; its pathogenesis is not understood completely. We include here a literature review of cardiac blackleg and a description of 2 cases in 12–15-mo-old feedlot steers in Argentina. Fourteen of 1,190 steers died suddenly over a period of 10 d. Postmortem examinations were performed on 5 of these animals. Grossly, severe, diffuse, fibrinous pericarditis and pleuritis, multifocal necrohemorrhagic myocarditis, diffuse pulmonary congestion, mild splenomegaly, and moderate congestion of meningeal vessels were observed. No significant gross lesions were observed in the skeletal muscles of any animal. Histology was performed on 2 of the steers. The main microscopic features were necrotizing myocarditis with myriad intralesional gram-positive rods with subterminal spores plus fibrinosuppurative pericarditis and pleuritis. C. chauvoei was detected by immunohistochemistry and PCR in the myocardium of both animals. These findings confirm a diagnosis of cardiac blackleg in these 2 steers and presumptively in the other affected animals.

Prevalence of Cardiac Lesions in Cases of Bovine Blackleg in Tennessee (USA), 2004–2018

“…Lastly, cardiac lesions in the absence of skeletal muscle lesions were observed in 4 cases in the current study. A similar observation was made in 2 cases of bovine blackleg in Trenque Lauquen, Argentina [11]. Such an occurrence is usually rare but should be further explored in future studies.…”

“…The pathogenesis of blackleg in cattle has been recently and thoroughly reviewed [1,2,11]. Cardiac lesions may be the result of hematogenous dissemination of the bacteria and/or toxins to the heart.…”

“…Prior to that study, cardiac lesions were considered a less common occurrence [2,9,10]. Cardiac lesions in the absence of skeletal lesions were reported in 2 cases of bovine blackleg in Trenque Lauquen (Argentina) [11]. In recent outbreaks of bovine blackleg, cardiac lesions were only reported in 11 of 43 cattle (25.6%) in an Irkutsk (Russia) farm [12] and in 13 of 15 cattle (88.6%) in a Punjab (Pakistan) farm [13].…”

Ethno-medicinal Approach to Cure Animal Diseases

“…The animal's skeletal muscles were free of any detectable gross lesions. Two of the steers had underwent histology (Morrell et al 2022). There was fewer animal than human reports, at a coarser spatial scale, but in places where there were clusters of human cases.…”

Development and Testing of Latex Antigen for Serological Diagnosis of Emphysematous Carbuncle in Animals

“…Whereas serological methods are used in very rare cases and are used to identify common clostridium antigens. Thus, in the report of Morrell et al (2022), it is indicated that the test with labelled fluorescent antibodies (FAT) is not specific for C. chauvoei and will be positive in the presence of C. septicum, C. novyi, or C. sordelii. Therefore, microbiological confirmation of the pathogen is a prerequisite in cases where the serological method is used.…”