Funguses (also called fungi) are parasitic, spore-producing organisms. They obtain their nourishment by absorbing food from the hosts on which they grow. Many species of fungus exist in the environment, but only a very few cause infections. The primary source of most infections is soil. Fungal infections can be acquired by inhalation, ingestion, or through the skin (for example, through a cut or wound).
Some fungal infections can cause disease in otherwise he
Clostridium perfringens is a bacterium that is widely distributed in the soil and the gastrointestinal tract of animals. It has the ability to produce poisonous substances (toxins) outside of the bacterial cell. Inflammation of the intestines (enteritis) and absorption of toxins (known as enterotoxemia) occur when these poisonous substances are released. Five types of Clostridium perfringens have been identified, but only one, Type A,
Canine ehrlichiosis is usually caused by the rickettsia Ehrlichia canis, although other types of Ehrlichia are sometimes involved. (Rickettsiae are a specialized type of bacteria that live only inside other cells.) Carried by ticks, the organism infects a certain type of white blood cell (called monocytes) and causes fever and other signs. A related organism, Ehrlichia ewingi, targe
Canine herpesviral infection is a severe, often fatal, disease of puppies. In adult dogs, it may be associated with upper respiratory infection, eye disease, an inflammation of the vagina marked by pain and a pus-filled discharge (in females), or inflammation of the foreskin of the penis (in males).
The disease is caused by a canine herpesvirus that occurs worldwide. Transmission usually occurs by contact between susceptible puppies or dogs and the infected o
Canine distemper is a highly contagious, whole body, viral disease of dogs. It is characterized by fever, loss of white blood cells, nasal discharge, digestive signs, and inflammation of the lungs and brain. The disease is seen worldwide in Canidae (dogs, foxes, wolves), Mustelidae (including ferrets, mink, and skunks), and several other species of wild animals.
Most cases of canine distemper d
Botulism is a motor paralysis caused by eating food containing the toxin (a poisonous substance) produced by Clostridium botulinum bacteria. This bacterium grows rapidly in decomposing animal tissue and sometimes in plant material. It results in rapid death due to the paralysis of vital organs. Botulism is an intoxication, not an infection.
There are 7 types of Clostridium botulinum; the C
Anthrax is an often fatal infectious disease that can infect all warm-blooded animals, including dogs and humans. Underdiagnosis and unreliable reporting make it difficult to estimate the true rate of occurrence of anthrax worldwide; however, anthrax has been reported from nearly every continent. Throughout the past hundred years, animal infections have been seen in nearly all states, with the highest frequency in the Midwest and West. Presently, anthrax is found mos
Amyloidosis is a condition that occurs when amyloid, a substance composed of abnormally folded protein, is deposited in various organs of the body. Some types of amyloidosis are hereditary in dogs. (Chinese Shar-Peis are known to be at risk for hereditary amyloidosis.) Others occur as a result of diseases, such as heartworm infection, various cancers, or other severe inflammatory or immune-related conditions. However, the cause is often unknown.
Actinomyces bacteria normally live in the mouth and in the nasal passages near the throat. Several species are associated with diseases in dogs.
Actinomyces bovis has been identified infrequently in infections in dogs and other mammals. Disease occurs when this bacterium is introduced to underlying soft tissue through penetrating wounds of the mouth (such as those that occur from carrying sharp objects in the mouth or r
Actinobacillosis is caused by bacteria in the genus Actinobacillus. Several different forms of disease occur, depending on the particular species of Actinobacillus involved and the type of animal infected. Soft tissue infections are common, and lymph node involvement is frequently a step in the spread of the disease throughout the animal’s entire body. Bony tissue close to infected muscles or other tissue may also