'Cara inchada' of cattle, an infectious, apparently soil antibiotics-dependant periodontitis in Brazil

摘要

Resumo l. Introduction 2. Disease history, clinical signs and pathological alterations of "cara inchada" in cattle (CI) 3. Histopathological findings 4. There is no scientific evidence of a mineral involvement in the etiology of CI 5. Bacterial isolations from periodontal CI-lesions 6. Characterization of anaerobic bacteria isolated from periodontal CI-lesions 7. Cattle affected by CI-periodontitis recovered after their transfer to a CI-free area 8. Panicum maximum-pastures free of weeds appeared to contain a determinant factor for the development of CI-periodontitis 9. Bacteriological monitorship of the regression and cure of CI-periodontitis 10. Confinement of calves affected by CI led to healing of the periodontal lesions 11. Avoidance of burning the cut forest did not help to recover CI-calves from the disease 12. The milk of the mother-cows, kept on CI-prone pastures, seemed to contain the supposed determinant factor for development of the periodontitis in their calves 13. Occurrence of CI in the "Cerrado" (tree-savanna) after its first cultivation for pasture formation 14. Outbreak of CI in the "High Pantanal" of Mato Grosso after the first cultivation of a virgin area with Panicum maximum-grass 15. Renewed outbreaks of CI on farms, when long-standing undisturbed soils were freshly cultivated for pasture improvement or forage production 16. Inefficiency of parenteral administration of antibiotics for the treatment of CI-periodontitis 17. The effect of antibiotics given as additives in mineral mixtures to prevent CI-periodontitis 18. Efficacy of orally administered virginiamycin for the recovery of calves from CI-periodontitis 19. "Cara inchada" and cellular immunity 20. Modification of the soil microflora after the first cultivation of virgin soils or after new cultivation of long-standing undisturbed soils in former CI-prone areas 21. Streptomycin and actinomycin increase the adherence on oral epithelial cells of the Bacteroides melaninogenicus group associated with the periodontal CI-lesions 22. Final considerations Acknowledgements References     ABSTRACT.- D??bereiner J., Dutra I.S., Rosa I.V. & Blobel H. 2000. "Cara inchada" of cattle, an infectious, apparently soil antibiotics-dependant periodontitis in Brazil. Pesquisa Veterin??ria Brasileira 20(2):47-64. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Serop??dica, Rio de Janeiro 2385l-970, Brazil. The objective of this review on the investigation of "cara inchada" in cattle (CI), pursued over the last 30 years, was to elucidate the pathogenicity of the disease and come to proper conclusions on its etiology. CI has been widely considered to be of nutritional origin, caused primarily by mineral deficiency or imbalance. However, the disease consists of a rapidly progressive periodontitis, affecting the periodontal tissues at the level of the premolars and molars during the period of tooth eruption generally starting in young calves. The disease led to great economic losses for farmers in central-western Brazil, after the occupation of new land for cattle raising in the 1960s and 1970s. The lateral enlargement of the maxillary bones of affected calves gave the disease the popular name of "cara inchada", i.e., swollen or enlarged face. The enlargement was found to be due to a chronic ossifying periostitis resulting from the purulent alveolitis of CI. Black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with Actinomyces (Corynebacterium) pyogenes, were isolated in large numbers from the periodontal lesions. B. melaninogenicus could be isolated in small numbers also from the marginal gingiva of a few healthy calves maintained on CI-free farms. "In vitro"-assays showed that streptomycin and actinomycin, as well as the supernatants of cultivates of actinomycetes from soils of CI-prone farms, applied in subinhibitory concentrations to the bacteria tested, enhanced significantly (up to 10 times) the adherence of the black-pigmented B.melaninogenicus to epithelial cells of the bovine gingiva. The antibiotics are apparently produced in large quantities by the increased number of soil actinomycetes, including the genus Streptomyces, that develop when soil microflora are modified by cultivating virgin forest or "Cerrado" (tree-savanna) for the first time for cattle grazing. The epidemiology of CI now provides strong evidence that the ingestion with the forage of such antibiotics could possibly be an important determinant factor for the onset and development of this infectious periodontitis. The antibiotic enhanced adherence of B.melaninogenicus to the sulcus-epithelium of the marginal gingiva, is thought to allow it to colonize, form a plaque and become pathogenic. There is experimental evidence that this determinant factor for the development of the periodontitis is present also in the milk of the mothers of CI-diseased calves. It