Hamid - Skin diseases of cattle in the tropics a guide to diagnosis and treatment

Mohamed E. Hamid

Faculty of Veterinary Medicine, University of Khartoum, Khartoum North, Sudan

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ISBN: 978-0-12-811054-6

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M.E. Hamid, Current address: College of Medicine, King Khalid University, Abha, Saudi Arabia

Skin Diseases of Cattle in the Tropics: Guide to Diagnosis and Treatment is a clinical and practical guide to help field veterinarians, veterinary students, and technicians to make appropriate and differential diagnoses. It provides quizzes of clinical cases and demonstrates more than 100 images of characteristic lesions and laboratory findings of major skin diseases and diseases with skin manifestations prevalent in tropical areas notably the Sub-Saharan African countries. This self-learning and easy-to-use instructional guide, the only one of its kind in the field of veterinary medicine, provides, firstly, the condition (as a quiz); followed by its laboratory diagnosis; then answers to the quiz and a summary of the disease.

The book was proposed in order to make the subject accessible for practicing veterinarians and useful for those who have neither seen nor had the chance to see such diseases in the field or clinics. Such diseases are important not only in the tropics but can be encountered in many countries in subtropical and temperate zones.

The motive to write this title was the many photos of typical diseases I have witnessed and then treated during more than 20 years service at the University of Khartoum Veterinary Clinic (Shambat), during my stay at South Darfur State as a Visiting Assistant Professor, and during field tours with veterinary students to more than 13 states in central, east, and west Sudan between 1985 and 2003 and from visits to Ethiopia, Chad, Kenya, Egypt, the Kingdom of Saudi Arabia, and the Republic of South Africa.

A number of scientific photos have been obtained with courtesy from published or unpublished work of colleagues. Acknowledgments of these sources are provided where relevant. To all who provided such indispensable materials I am very grateful. I appreciate particularly the helpful thoughts of Drs Mohamed Ahmed Hamad, Mohamed Mahmoud Sirdar, Adam Daoud, Mohamed Awad Musa, Kamal Siddig, Hussein Ahmed, Mukhtar T. Abu Samra, Khitma H. Al Malik, Jeruesha Nichols, and Helder Cortes.

A list of references and websites are listed to guide readers to more in-depth knowledge of skin diseases in bovine. Also, the index is complete and contains multiple entries for a single entity when needed.

Clinical Presentations, Laboratory Diagnosis and Disease Summaries

Outline

Dermatophilosis (Streptothricosis) is an acute or chronic bacterial infection of the epidermis affecting animals and human. It is characterized by an exudative dermatitis with heavy scab formation and causes significant economic loss especially in cattle in tropical areas. Etiology: Dermatophilus congolensis, a gram-positive facultative anaerobic actinomycete bacterium which is spread by contact with infected animals, via contaminated environmental objects, and probably ticks. The disease is diagnosed by demonstrating branching gram-positive filaments in scabs; or isolating the organism in blood agar containing selective antibiotics and increased carbon dioxide tension. The disease is treated by topical (sulfur lime) or systemic antibiotics (gentamycin or penicillin G or tetracycline) and prevention can be achieved by managing ectoparasites and isolating or culling of infected animals.

Dermatophilosis; streptothricosis; dermatitis; scab; Dermatophilus congolensis; actinomycete bacterium

What is your diagnosis?

A chronic skin infection in a zebu cow showing exudative dermatitis with heavy scab on the head, neck, and back. Note the enlargement of the superficial lymph nodes. Usually there is little effect on general health of the animal. Early stages show raised clusters of hairs tangled jointly as a wetted paintbrush (typical lesions). When these lesions merge, crusts (scab) are formed which develop to become wart-like lesions ranging from 0.5 to 2 cm in diameter.