Immunopathological investigations on bovine digital epidermitis

Abstract

Paraffin-embedded fragments of bovine digital skin lesions were sectioned and stained with Warthin-Starry, haematoxylin and eosin, Grocott's methenamine silver and immunohistochemical techniques. Microorganisms observed in the silver-stained sections were classified into four major morphological groups. Spirochaetes were the most prevalent organisms, but bacillary and coccoid elements were also present in most sections. Immunohistochemical probing demonstrated that approximately 80 per cent, 46 per cent and 41 per cent of the digital and interdigital dermatitis sections stained positively with polyclonal antisera to Treponema pallidum, Campylobacter jejuni and Fusobacterium necrophorum, respectively. An unidentified branching filamentous organism (presumed to be an actinomycete) was consistently present in the sections of samples from mild interdigital lesions.

Evidence of Multiple Treponema Phylotypes Involved in Bovine Digital Dermatitis as Shown by 16S rRNA Gene Analysis and Fluorescence In Situ Hybridization

“…In periodontal disease, T. denticola is considered a key organism together with other proteolytic gram-negative bacteria, especially Porphyromonas gingivalis (33). In DD lesions, Treponema species are also suspected to be strongly implicated in disease progression, along with other bacterial morphotypes, including bacilli and cocci, which have been observed scattered between the spirochetes (10,39). Until now, however, no specific species or phylotypes have been identified as the major pathogens in DD.…”

“…A bacterial etiology of DD is supported by the observation that cattle infected with DD respond to antibiotic treatment and that virus isolation from affected tissues has been unsuccessful (13). The disease appears to be polymicrobial; a variety of bacteria has been cultivated from DD lesions (19,32), and although spirochetes seem to be the predominating group, various rods and cocci can also be recognized in microscopic sections of DD specimens (10,39). A recently discovered species, Guggenheimella bovis, has been suggested as a potential pathogen but has until now been isolated only from a few DD-infected animals (30,35).…”

Genetic Heterogeneity among Strains ofTreponema phagedenis-Like Spirochetes Isolated from Dairy Cattle with Papillomatous Digital Dermatitis in Japan

“…Pulsed-field gel electrophoresis and PCR-based random amplified polymorphism DNA methods revealed considerable diversity among strains isolated not only from different cattle but also from the same individuals. These findings may provide further evidence for the role of these treponemes in the pathogenesis of persistent PDD.Papillomatous digital dermatitis (PDD) is an infectious foot disease in cattle that was first reported in Italy in 1974 (4) and is now recognized throughout the world (3,8,31). In Japan, PDD in dairy cattle is now found in most regions (24,26,37) since the first case was reported in 1992 (20).…”

“…Papillomatous digital dermatitis (PDD) is an infectious foot disease in cattle that was first reported in Italy in 1974 (4) and is now recognized throughout the world (3,8,31). In Japan, PDD in dairy cattle is now found in most regions (24,26,37) since the first case was reported in 1992 (20).…”

Treponemes Detected in Digital Dermatitis Lesions in Brazilian Dairy Cattle and Possible Host Reservoirs of Infection

“…A lthough bovine digital dermatitis (BDD) has been known to occur in Brazil since the early 1990s (1), there have been no attempts to describe the possible pathogens involved, apart from reports of histopathological (2) and electron microscopic (3) findings. Treponema species are difficult to culture, so molecular approaches are useful for detecting and identifying these spirochetes (4,5).…”