Dermatophilus congolensis

Dermatophilus congolensis
This micrograph demonstrates a clustering of Dermatophilus congolensis bacteria using a Giemsa stain.
Scientific classification
Kingdom: Bacteria
Phylum: Actinobacterias
Class: Actinobacterias
Order: Actinomycetales
Family: Dermatophilaceae
Genus: Dermatophilus
Species: D. congolensis
Binomial name
Dermatophilus congolensis
van Saceghem, 1915

Dermatophilus congolensis is a gram positive bacterium and is the etiologic agent of a disease called Dermatophilosis (sometimes called Mud fever) in animals and humans, a dermatologic condition that manifests itself with the formation of crusty scabs that contain the microorganism. Some people erroneously call it mycotic dermatitis.[1] Rainscald is another condition often seen in animals, which is also caused by Dermatophilus congolensis bacteria.

Contents

Morphology

D. congolensis is facultative anaerobic actinomycete bacteria. It has two morphologic forms: filamentous hyphae and motile zoospores. The hyphae are characterized by branching filaments (1-5 µm in diameter) that ultimately fragment by both transverse and longitudinal separation into packets of coccoid cells. The coccoid cells mature into flagellated ovoid zoospores (0.6-1 µm in diameter).[1] With the microscope one can observe the characteristic "tramcar line"-like D. congolensis colonies together with gram positive thin filaments and coccoid forms.[2]

Cultivation

D. congolensis is a carboxiphylic germ, so they need carbon dioxide to properly grow on laboratory media. The germ grows well on sheep-blood enriched agarose media; the media must then be incubated at a 37 degrees Celsius temperature and a 5-10% CO2 atmosphere. The bacteria colonies become visible in 24–48 hours. Initially they are small, with a ~1 mm diameter and with a grey-yellow colour. After 3–4 days the isolated bacterial colonies can reach a 3 mm diameter, they have a rough surface and a yellow-golden pigmentation. Around the colonies circular hemolysis zones can be seen.[2]

Pathogenesis

D. congolensis causes severe skin infections in animals and humans. More frequently cattle, horses, sheep and goats are affected. Humans can also get this skin disease if elementary hygiene measures are not respected after dealing with infected animals. This dermatologic condition is known by many names: cutaneous streptothrichosis (on cattle, goats, and horses), "rain-scald" (on horses), "lumpy wool" (on sheep), "strawberry foot rot".[1]

The pathogenic factors are very diverse, but the most important ones are the ones of enzymatic nature (adenase and lecitinase).

References

  1. ^ a b c Merck Veterinary Manual
  2. ^ a b Gheorghe Rapuntean, Sorin Rapuntean (editors) (2005). Bacteriologie Veterinara Speciala (I ed.). Editura AcademicPress, Cluj-Napoca, Romania. ISBN 973-7950-95-X. 

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Dermatophilus congolensis — A species of motile, nonacid fast, aerobic to facultatively anaerobic, Gram positive bacteria that is the etiologic agent of dermatophilosis; also causes proliferative dermatitis. [ …   Medical dictionary

  • Mud fever — Dermatophilus congolensis, a causative agent of mud fever Mud fever is a group of diseases of horses causing irritation and dermatitis in the lower limbs of horses. Often caused by a mixture of bacteria, typically Dermatophilus congolensis, and… …   Wikipedia

  • dermatophilosis — An infectious exudative dermatitis of cattle, sheep, goats, horses, and other animals (occasionally humans) caused by the bacterium Dermatophilus congolensis; severe (sometimes fatal) d. is seen in cattle in Africa and the Caribbean, invariably… …   Medical dictionary

  • ACTINOMYCÈTES — Les Actinomycètes sont des Bactéries dont la croissance donne lieu à des colonies constituées d’hyphes, c’est à dire de filaments qui irradient, par croissance centrifuge, tout autour du germe qui leur a donné naissance. Cela explique leur… …   Encyclopédie Universelle

  • Horse markings — These young horses, though all the same color, exhibit uniquely different markings, which can be used to identify individual horses …   Wikipedia

  • Rainscald — (also called rain rot or dermatophilosis ) is caused by the same bacteria that can contribute to Mud fever Dermatophilus congolensis . It is a skin infection that can appear on horses backs, if they re left out in wet weather. It is more commonly …   Wikipedia

  • Renitello — Rénitello Rénitello Région d’origine Région Madagascar Caractéristiques …   Wikipédia en Français

  • Rénitello — Espèce Vache (Bos taurus) Région d’origine Région Madagascar …   Wikipédia en Français

  • actinomycete — actinomycetous, adj. /ak tin oh muy seet, muy seet , ak teuh noh /, n. Bacteriol. any of several rod shaped or filamentous, aerobic or anaerobic bacteria of the phylum Chlamydobacteriae, or in some classification schemes, the order… …   Universalium

  • Strahlenpilze — Strahlenpilze,   Aktinomyzeten, Streptomyzeten, Sammelbezeichnung für eine große Gruppe v. a. im Boden lebender Bakterien; Strahlenpilz ist ebenso Bezeichnung für die zu dieser Gruppe gehörende Ordnung Actinomycetales. Auf Nährböden wachsen die… …   Universal-Lexikon


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.