Selected infectious and parasitic diseases of animals

animal(s) affected name(s) of disease nature of disease

Diseases of bacterial origin

most mammals, chickens necrobacillosis, calf diptheria, bovine foot rot, necrotic hepatitis, dermatitis caused by Sphaerophorus necrophorus; organism invades tissue and causes tissue death (necrosis) after other wounds or infections have occurred; i.e., disease is known as a secondary infection

cattle, sheep, horses, chickens, humans, many other animals botulism caused by toxins produced by Clostridium botulinum; results from eating toxins released in decayed or spoiled foods; toxins cause rapid paralysis of nerves in throat and all muscles; almost always fatal

swine, cattle, sheep, goats, rabbits, humans, dogs, many other animals listeriosis, circling disease, meningoencephalitis caused by Listeria monocytogenes; symptoms vary in affected animal; organism may affect the central nervous system (brain, spinal cord) or the membranes surrounding it or cause necrosis of heart muscles, localized tissue death in liver, or a septicemia (persistence of bacteria in the bloodstream)

swine, cattle, sheep, goats, horses, turkeys, humans erysipelas, diamond-skin disease caused by Erysipelothrix insidiosa; manifestations include septicemia and pathological discontinuities of tissue (lesions) in skin, heart, joints (in swine); arthritis (in sheep, occasionally in cattle, horses, goats); septicemia and death (in turkeys); skin lesions (in humans)

cattle, sheep, goats, horses, mules anthrax, splenic fever, charbon caused by Bacillus anthracis; spores (inactive forms) of organisms in soil, transmitted through insect bites or food; manifestations include hemorrhage and edema (accumulation of fluid) in tissues

swine, cattle, sheep, horses, mules malignant edema, gas gangrene caused by Clostridium septicum; spores enter from dirt into injured tissue, cause severe gangrene (rotting of dead tissue), swelling; prognosis (outlook) poor

swine, cattle, sheep, goats pyobacillosis caused by Corynebacterium pyogenes; characterized by multiple abscesses (localized collections of pus) throughout the body; may result in debilitation (including arthritis in swine) and death

primarily swine, cattle, goats (secondarily in humans and other animals) brucellosis, Bang's disease, contagious abortion; undulant fever, Malta fever (in humans) caused by Brucella abortus, B. melitensis, B. suis; primarily affects genital organs in both sexes; may cause abortion, sterility, infection of fetus in female, local lesions in various tissues; pasteurization of milk has controlled the disease in humans

swine, cattle, sheep shipping fever, pasteurellosis, hemorrhagic septicemia caused by Pasteurella multocida and P. hemolytica; also in conjunction with viral agents; cause great economic losses throughout the world; manifestations may include acute to chronic respiratory disease; the various causative organisms vary in virulence (degree of pathogenicity); an acute form (i.e., short, severe) affects rabbits

horses, mules, donkeys (humans less susceptible) glanders, farcy, malleus caused by Malleomyces mallei; organisms enter animal through digestive tract, travel via blood to lungs, trachea, and skin, and form ulcers; an acute form causes death, a chronic type may persist for years; human infections occur from exposure of broken skin to affected animals

horses (mules, donkeys less susceptible) strangles, distemper, infectious adenitis caused by Streptococcus equi; most common in young, undernourished horses in crowded conditions; manifested by high temperature, nose infections, and abscesses in lymph glands of neck

horses purpura hemorrhagica, petechial fever cause unknown, but associated with Streptococcus equi; noncontagious, follows acute infections and toxemias; characterized by generalized hemorrhages in tissues and the accumulation of fluid (edema); relapses often occur

primarily horses ulcerative lymphangitis or cellulitis caused by Corynebacterium pseudotuberculosis; chronic disease, develops slowly following the entrance of bacteria through skin; affects hind legs, sometimes severely

horses (males most susceptible); sometimes swine, cattle; rarely dogs or cats tetanus, lockjaw caused by toxins produced by Clostridium tetani; bacteria enter tissue at time of injury, produce toxins in necrotic tissue; affected animals become stiff; death results from suffocation

swine streptococcal infection caused by Streptococcus species; younger pigs more easily infected; symptoms varied (e.g., septicemia, arthritis, uterine inflammation, middle-ear infection, multiple abscesses)

swine, accidentally in other animals salmonellosis, enteritis, swine typhoid caused by Salmonella choleraesuis; may be acute (i.e., have a short, severe course) or chronic (persist for a long time); symptoms include loss of weight, sometimes acute septicemia

swine, cattle actinobacillosis, botryomycosis, big head caused by Actinobacillus lignieresii; organism a normal inhabitant of mouth, enters tissues through ulcers or wounds; symptoms include abscesses

cattle leptospirosis, hemoglobinuria caused by Leptospira species; symptoms of acute form include abortion, bloody milk, hemoglobin (blood pigment) in urine, kidney disease, and destruction of red blood cells; a milder form also exists

cattle infectious bovine pyelonephritis, infectious cystitis caused by Corynebacterium renale; usually observed in pregnant cattle in winter; a slowly developing disease that affects kidneys and bladder

primarily cattle (rarely humans, swine, sheep, horses) tuberculosis, pearly disease caused by Mycobacterium tuberculosis; a chronic disease characterized by lesions, usually in lungs and lymph nodes, but sometimes in many other organs

cattle (rarely sheep) bacillary hemoglobinuria, red water disease caused by Clostridium hemolyticum; spores eaten with food, develop into active cells, migrate to liver, and produce infarcts (tissue death); usually fatal within 36 hours

cattle, sheep pinkeye, infectious keratitis, keratoconjunctivitis caused by Moraxella bovis (in cattle), Colesiota conjunctivae (in sheep); affects eyes; may result in blindness; a very contagious disease whose spread may be influenced by dust irritation or possibly by viral invasion

cattle, sheep Johne disease, paratuberculosis caused by Mycobacterium paratuberculosis; a chronic disease; causes diarrhea, progressive weight loss

cattle, sheep vibriosis, epizootic abortion caused by Vibrio fetus; a venereal disease (i.e., transmitted by sexual contact) in cattle; transmitted in contaminated food and water in sheep; commonly results in infertility or abortion in cattle, abortion in sheep

cattle, sheep (occasionally swine, goats, deer, horses) blackleg, black quarter, quarter ill caused by Clostridium feseri (chauvoei); spores transmitted from soil to animal through wounds or cuts; symptoms include lameness, gangrene of affected tissues (usually in leg muscles); usually fatal

sheep enterotoxemia, overeating disease, pulpy kidney caused by Clostridium perfringens type D; affected lambs usually fat or feeding on rich clover pasture; usually fatal within a day from acute toxemia (absorption of bacterial toxins)

primarily sheep pseudotuberculosis, caseous lymphadenitis caused by Corynebacterium ovis; organisms transmitted to animal through breaks in the skin; slowly developing abscesses (usually in lungs or lymph nodes) may rupture and spread throughout body

sheep, goats (occasionally cattle) black disease, infectious necrotic hepatitis caused by Clostridium novyi; organisms probably present normally in intestinal tract, associated with fluke (parasitic worm) movements in liver; produce liver damage, toxemia, and death

Diseases of viral origin

mammals rabies, hydrophobia, lyssa, mad dog, le Rage caused by rabies virus; transmitted primarily through the bite of a rabid animal; wild animals (e.g., skunks, squirrels, bats) a reservoir for infection; disease characterized by central-nervous-system symptoms (e.g., rage, excitability, paralysis of jaw with salivation), general paralysis, and death

mammals (especially cattle) bovine warts, papillomatosis caused by papilloma viruses; warts of variable size develop, usually on sides of head and neck of cattle, sometimes on sex organs

many mammals (e.g., swine, cattle, sheep, goats, horses) pox, variola caused by pox virus; often an acute highly infectious disease, characterized by formation of papules (small solid elevations), vesicles (small liquid-containing sacs), and pustules (small pus-filled elevations) on the skin

swine, cattle (also rats, dogs, cats) pseudorabies, Aujeszky disease, mad itch caused by pseudorabies virus; affected animals rub body parts, undergo spasmodic muscle contractions, froth at the mouth, and show nervous irritability; usually fatal

young pigs transmissible gastroenteritis (TGE) caused by TGE virus; acute and fatal to pigs less than two to three weeks old; virus attacks absorptive surfaces of small intestine

swine hog cholera, swine fever, swine pest caused by hog-cholera virus; infectious disease; may be acute or chronic; spread by flies, animal contact, garbage, contaminated pastures; symptoms include high fever, severe hemorrhages in skin and organs

swine vesicular exanthema (VE) caused by VE virus; vesicles form on snout, mouth, abdominal wall; foot lesions occur; highly infectious, spread through animal contact or raw pork scraps in garbage; fatal usually only in young pigs

swine, ferrets, mice swine influenza, hog flu caused by swine-influenza virus; bacterium; Hemophilus suis; acute contagious disease; virus enters animal through lungworm larvae, acute infection occurs if Hemophilus organisms are in lung; symptoms include fever, pneumonia, bronchitis

swine, cattle, horses vesicular stomatitis (VS), mouth thrush caused by VS virus; effects varied; e.g., high fever, salivation, vesicles in mouth region, lack of appetite (in horses); inflammation of mammary glands, vesicles in mouth region, inflammation of feet (in cattle); snout and mouth lesions, severe feet involvement (in swine)

cattle sporadic bovine encephalomyelitis (SBE), Buss disease caused by SBE virus; weakens calves; an infection of brain and membranes of brain and spinal cord; recovery often occurs

cattle infectious bovine rhinotracheitis (IBR), red nose, pinkeye, dust pneumonia caused by IBR virus; acute infection followed by secondary bacterial infections (Pasteurella multocida, Spherophorus necrophorus) in lungs, sex organs, eye; nostrils swell, become red

cattle, buffalo, deer malignant catarrhal fever (MCF), head catarrh, snotsiekte, epitheliosis caused by MCF virus; numerous symptoms include rapid weight loss, eye lesions, nasal discharge, muscular twitching, convulsions; usually fatal

cattle, sheep bluetongue, soremuzzle, catarrhal fever caused by bluetongue virus; virus transmitted through gnats (small flies); a serious problem in sheep; numerous symptoms; recovery very slow; usually less than 10 percent mortality of a flock

sheep (also transmissible to cows) ovine virus abortion (OVA), enzootic abortion caused by OVA virus; causes economic losses through abortion, weak lambs, and poor breeding efficiency

sheep, goats, humans contagious ecthyma (CE), sore mouth, doby mouth, orf, pustular dermatitis caused by CE virus; udder, lips, and nose of sheep affected; secondary bacterial invasion may result in death, but animals usually recover

horses equine infectious anemia (EIA), swamp fever, malarial fever caused by EIA virus; transmitted by mosquitoes, lice, flies, and hypodermic needles; either acute, chronic, or latent (not manifest); varied symptoms include intermittent fever, loss of weight, jaundice, hemorrhages, anemia, and fluid in body cavities

horses equine viral arteritis (EVA), infectious arteritis caused by EVA virus; an acute contagious disease similar to EVR in symptomatology but causes damage to small arteries

horses, mules, humans, laboratory animals equine encephalomyelitis (EE), sleeping sickness, viral encephalitis caused by EE virus; many viral strains transmitted by an insect (usually mosquitoes or mites or ticks); disease causes inflammation of brain cells; the many symptoms include death; inapparent infections occur in chickens, pigeons, and pheasants

horses (also guinea pigs, mice, hamsters) equine viral rhinopneumonitis (EVR), equine virus abortion caused by EVR virus; disease highly contagious; symptoms include high fever, mild upper-respiratory involvement, and usually abortion with liver damage of fetus in pregnant mares

Diseases of fungal origin

many domestic, laboratory, and wild mammals histoplasmosis, reticuloendothelial cytomycosis caused by Histoplasma capsulatum; chronic; may resemble tuberculosis; granulomas (tumours) in lungs, liver, and spleen; intestinal involvement in dogs results in diarrhea

swine, cattle, sheep, horses, fowl, dogs, cats ringworm, tinea, trichophytosis caused by Trichophyton and Microsporum species; infectious skin disease caused by invasion of hair follicles; characterized by round crusty lesions, inflammation

swine, cattle, horses (humans secondarily) actinomycosis, lumpy jaw, wooden tongue caused by Actinomyces bovis; cattle manifest a bonelike swelling on upper or lower jaw; swine manifest a tumourlike enlargement of udder caused by infections from teeth of suckling pigs

cattle, horses, cats, dogs, humans cryptococcosis caused by Cryptococcus neoformans; usually caused by inhalation of contaminated dust; lungs affected primarily; disease may spread to almost any organ

cattle, sheep, dogs, humans coccidioidomycosis coccidioidal granuloma, San Joaquin Valley fever caused by Coccidioides immitis; in the acute respiratory form, symptoms include cough, with recovery in two weeks; in the more serious chronic form, gradual loss in weight, abscesses, and granulomas in various tissues, including skin, occur

primarily horses and humans sporotrichosis caused by Sporotrichum schenckii; occurs first as ulcers on skin, invasion of the lymph glands occurs, may spread throughout circulatory system

Diseases of rickettsial origin

swine eperythrozoonosis, ictero-anemia, yellowbelly caused by Eperythrozoon suis; organisms cause red-blood-cell destruction; both acute and mild forms; many animals with a mild form act as carriers

cattle anaplasmosis, South African gall sickness caused by Anaplasma marginale; infectious disease spread either by bloodsucking ticks, mosquitoes, or flies or by mechanical transmission (e.g., resulting from dehorning, vaccination); symptoms usually include extreme anemia from destruction of red blood cells; recovered animals are immunological carriers

Diseases of protozoal origin

most animals (including humans) toxoplasmosis caused by Toxoplasma gondii; transmission not clear but probably occurs by contaminated food or direct contact; symptoms include weakness, respiratory problems, lack of coordination, nodules throughout body, enlarged lymph nodes, and tissue death; treatment difficult

swine, cattle, sheep, goats coccidiosis caused by Eimeria zürnii, E. bovis, and ten other species; causative organisms found in most mature animals; symptoms result in loss of large amounts of blood and dehydration; mortality may be as high as 50 percent

cattle trichomoniasis caused by Trichomonas fetus; transmitted by sexual contact or by artificial insemination, symptoms include abortion, failure to conceive, inflammation of uterus; no symptoms apparent in infected bull that acts as a carrier

cattle Texas fever, cattle-tick fever, babesiasis, piroplasmosis, red water caused by Babesia bigemina; organism, which destroys red blood cells, is transmitted by ticks (Margaropus species) and mechanical means (i.e., surgical instruments, needles); symptoms include high fever, severe anemia, hemoglobin in urine; chronic forms occur; some animals act as carriers

horses dourine, equine syphilis, breeding disease caused by Trypanosoma equiperdum; transmitted by sexual contact or bloodsucking flies; affects sex organs, causes plaquelike areas on skin, paralysis of muscles, loss of condition

horses, mules, donkeys equine piroplasmosis, equine malaria, babesiasis caused by Babesia caballi, B. equi; acute cases may die quickly; animals with less-acute forms have varied symptoms (e.g., intermittent fever, jaundice, internal hemorrhages); anemia results from invasion of red blood cells by causative organisms; B. equi more pathogenic than B. caballi

Diseases of nematode (roundworm) origin

swine lungworms caused by Metastrongylus species; common symptoms include coughing and lung irritation

swine kidney worms caused by Stephanurus dentatus; mature worms live in urinary tract; larvae migrate to liver, produce lesions and weight loss

swine intestinal roundworm caused by Ascaris suum; migrations of organisms through lungs cause hemorrhages and pneumonia, may interfere with bile flow and food absorption

swine intestinal threadworm caused by Strongyloides; migration of large numbers of larvae cause tissue damage

cattle stomach worms caused by Ostertagia and Trichostrongylus species; symptoms include anemia, stunted growth, and diarrhea

cattle nodular worm caused by Oesophagostomum radiatum; nodules form in tissues; poor intestinal absorption caused by larvae (immature forms of organism) and nodules results in diarrhea

cattle verminous pneumonia caused by Dictyocaulus viviparus; ingested infective larvae migrate to lungs, produce coughing, discomfort, and pneumonia

sheep lungworms caused by Dictyocaulus filaria, Muellerius capillaris; symptoms include formation of lung nodules, collapse of portions of lungs

sheep hookworms caused by Bunostomum trigonocephalum; bloodsucking hookworms cause anemia, intermittent diarrhea

sheep filarial dermatitis caused by Elaeophora schneideri; symptoms include skin lesions

horses oxyuriasis (pinworms) caused by Oxyuris equi; worms cause irritation in the area around the anus

horses ascariasis (intestinal roundworms) caused by Parascaris equorum; larval forms cause damage; symptoms include defective intestinal absorption

horses strongylosis caused by Strongylus species; large numbers of worms weaken foals (newborn horses); migrating larvae may cause formation of clots in blood vessels and lameness

horses habronemiasis (summer sores) caused by Habronema species; habronema larvae may enter skin wounds, causing granulation; eye and stomach inflammations also occur

Diseases of platyhelminth (flatworm) origin

sheep tapeworm caused by Moniezia expansa; results in poor growth

sheep fringed tapeworm caused by Thysanosoma actinoides; causes digestive disturbances

horses tapeworm caused by Anaplocephala perfoliata; symptoms may include inflammation of gut and ulceration

Diseases of acanthocephalan (spiny-headed-worm) origin

swine spiny-headed worm caused by Macracanthorhynchus hirudinaceus; nodules form on small intestine; may result in peritonitis (inflammation of lining of internal organs)

Diseases of arthropod origin

cattle scabies (mange) caused by Chorioptes bovis, Psoroptes equi, Sarcoptes scabiei (mites); contagious skin diseases

cattle grubs caused by Hypoderma bovis (heel fly); migrating larvae produce tissue damage, cysts, and hide damage

cattle lice caused by Linognathus vituli, Solenopotes capillatus, Haematopinus quadripertusis (bloodsucking lice), Bovicola bovis (biting louse); symptoms include dermatitis and anemia

sheep screwworm infestations caused by many fly larvae (e.g., Cochliomyia hominivorax, Chrysomyia bezziana); flies lay eggs in open wounds; developing larvae (screwworms) burrow into tissue and destroy it

sheep psoroptic mange (sheep scab) caused by Psoroptes communis (mite); all parts of skin inflamed, particularly those covered with wool