Porcine Pathogens Flashcards
Actinobacillus pleuropneumonia
inject with enrofloxacin
Adenovirus
diarrhea and GI disease in piglets
Ascaris suum
nematode, treat with ivermectin . Primarily found in the small intestine of pigs. If there is a large enough burden of the worms, they can cause obstruction of the intestine, migrate into the bile ducts and cause icterus. Migration through the liver causes fibrosis or “white spots.” Pulmonary edema can also be a sequela of the larvae, causing abdominal breathing or “thumps.” Common in outdoor swine due to high environmental contamination. Susceptible to avermectin and piperazine
Atrophic rhinitis (AR)
caused by Bordetella bronchiseptica and Pasteurella multocida type D. Pigs become infected from the sow shortly after birth. Best way to control/eliminate AR is to select breeding stock that is negative for AR. Antibiotic treatment and flunixin will not reverse the condition and will probably not have any effects when nasal deviation is already present. If problem severe throughout herd, depopulation and restocking is an option. Can vaccinate with bacterin vaccines or purchase genetic stock free of AR
Brachyspira hyodysenteriae
Swine Dysentery - grower/finish pigs - diarrhea
Brachyspira pilosicoli
associated with spirochaetal colitis
Brucella suis
Commercial herds in US are free, by feral swine have tested positive for Burcella suis. Often occurs in healthy appearing animals, abortions occur at any stage in gestation. There are usually few fetal or placental lesions, but the fetus may by autolyzed.
Classical Swine Fever
Considered a foreign animal disease in the U.S. Pestivirus from the family Flaviviridae. Animals exposed to BVD (does not usually cause disease in pigs, but pigs exposed to the virus seroconvert) can cross-react to CSF assay.
Colibacillosis
Enteric E. coli
Edema disease cause
Enterotoxigenic E. coli (F18), fatal disease of rapid growing weaners pigs
Enterotoxigenic E. coli
produces a heat stable toxin called Stx2e *Shiga toxin 2e). When absorbed into the blood, this toxin destroys endothelial cells in small vessels, resulting in blood clots, hemorrhagic, ischemic necrosis, and edema in vital organs, including the brain. Presentation: weaner pigs with anorexia, diarrhea, and edema of the eyelids, forehead and lips, dyspnea and open-mouthed breathing, some weak and circling. Do not have fever. Treatment: Ceftiofur in sick animals and gentamicin in the water
Eperythrozoonosis
Eperythrozoon (mycoplasma) suis bacteria
Erysipelas
diamond-shaped skin lesions and necrosis of the ears and tail
Erysipelathrix rhusiopathrix
bacteria; cause of erysipelas, treat with penicillin
Exudative Epidermitis
“Greasy pig disease” caused by bacteria Staphylococcus hyicus
Fasciola hepatica
liver fluke - parasitic trematode, snail intermediate host (Galba truncatula), Oxfendazole treatment
Glasser’s Disease
Caused by Haemophilus parasuis. Usually characterized by sudden death but can often also lead to painful joints, pneumonia, and occasionally neurologic signs. Lesions show fibrinopurulent pleuritis, pericarditis, and peritonitis. Meningitis is usually responsible for the cause of neurologic signs and seizures. This disease most commonly affects piglets from 2 weeks to 4 months of age. Morbidity rate can reach up to 50-70% and mortality rate up to 10%.
PM: lesion polyserositis
Treatment: inject pigs with ceftifur
Greasy pig disease
exudative dermatitis caused by Staphylococcus hyicus. Causes dark, greasy, brown skin lesions in the axilla, groin, head, and face.
Haematopinnus suis
louse
Haemophilus parasuis
bacteria “glassers” Characterised by sudden death but can often also lead to painful joints, pneumonia, and occasionally neurologic signs. Lesions show fibrinopurulent pleuritis, pericarditis, and peritonitis. Meningitis is usually responsible for the cause of neurologic signs and seizures. Most commonly affects piglets from 2 weeks to 4 months of age.
Resistant to penicillin (used to be drug of choice) and all other choices are not permitted for use in food animals in the USA (ampicillin, ceftifur, enrofloxacin, florfenicol, spectinomycin, tetracyclines, tiamulin, tilmicosin, and potentiated sulfas)
Hemorrhagic Bowel Syndrome (HBS)
Present with sudden death, necropsy - grossly distended intestines with diffuse hemorrhagic tissue. Contents will be hemorrhagic and liquid (would be clotted if acute ileitis)
Isospora suis
causes coccidiosis in pigs Several anti-coccidial agents can be considered although efficacy may vary. Ponazuril, Sulfamethazine, amprolium, and decoquinate. Agents reduce parasite burdens and shedding, but are frequently con completely effective at eradicating the parasite.
Lameness differentials for young pigs
Mycoplasma hyorhinis, Streptococcus suis, Erysipelothrix rhusiopathiae, and Haemophilus parasuis
Lawsonia intracellularis
a proliferative enteritis of grower/finisher pigs - intracellular organism
Leptospirosis
most important problem: reproductive failure. Acute leptospirosis in young pigs causes fever, anorexia, hemolytic anemia, hemoglobinuria, jaundice, and failure to grow. Chronic infections in dam cause reproductive failure as late term abortions, mummies, or weak piglets that die in a few days. Dams usually recover, conceive again, and carry their litters to full term.
Treatment: Tetracylines
Metastrongylus spp.
lungworm - earth worms intermediate host
Microsporum nanum
dermatophyte - ringworm in pig
Mycoplama hyonoviae
bacteria causes arthritis and it typically seen in older pigs
Mycoplasma hyorhinis
Diagnosed by PCR. can cause arthritis in swine and is found in younger pigs while M. hyosynoviae is found in older pigs. Mycoplasmas are difficult to culture and require special media, PCR testing is a more sensitive and quicker technique.
Mycoplasma hyponeumonia
attach to and disrupt pulmonary mucociliary apparatus and thus preventing it from functioning properly. This, in turn, makes the lungs much more susceptible to other bacterial infections.
Mycoplasma suis
commonly causes anemia, primarily lives on the surface of erythrocytes and causes anemia in pigs of all ages.
Oesophagostomum ssp
nematode, susceptible to avermectin and piperazine
found in lumen of large intestine
Most infections are asymptomatic, but heavily infected pigs may show anorexia, emaciation, and GI disturbances
Paramyxovirus
“blue eye”
Parvovirus
Parvovirus infections in gilts usually results in an inapparent infection. Bred gilts returning to heat most consistent sign. A transient leukopenia may occur, but the first noticed sign is usually the return to heat of a bred gilt. This is likely due to embryo resorption. Other signs may include mummified fetuses, weak piglets, small litters, or still births. Abortions are rare because the endometrium is not affected, so there is no PGF2-alpha released.
Picronavirus
non-enveloped upper respiratory virus
Pityriasis rosea
non-contagious, unknown etiology, resolves on its own
Do not need to treat
Porcine Circovirus Associated Disease (PCVAD)
High mortality
Diagnosis required 3 parts: 1. At least a doubling of mortality (clinical history). 2. Demonstration of lymphoid depletion (histopathology). 3. High number of PCV2 antigen in the lesion (immunohistochemistry on tissue).
This disease causes illness in piglets, with clinical signs including progressive loss of body condition, visibly enlarged lymph nodes, difficulty in breathing, and sometimes diarrhea, pale skin, and jaundice
Porcine Reproductive and Respiratory Syndrome (PRRS)
Cause of abortion - can vaccinate
Test for virus via serum PCR, sow usually abort shortly after infection and should still be viremic.
Proliferative enteropathy (PHE)
caused by Lawsonia intracellularis. Due to its acute nature, PHE does not always allow for gross evidence of proliferation. Lesions located in the small intestines, as well as indications of red clotted blood, is almost pathognomonic for this condition.
pseudorabies
“Aujeszky’s disease” - Respiratory infection is usually asymptomatic in pigs more than 2 months old, but it can cause abortion, high mortality in piglets, and coughing, sneezing, fever, constipation, depression, seizures, ataxia, circling, and excess salivation in piglets and mature pigs. Mortality in piglets less than one month of age is close to 100%, but it is less than 10% in pigs between one and six months of age. Pregnant swine can reabsorb their litters or deliver mummified, stillborn, or weakened piglets
Rotavirus
small intestinal diarrhea
Salmonella enterica (formerly choleraesuis)
rectal strictures
Samonella typhimirin
associated with button ulcers in the colon
Spirochaetal colitis
diarrhea 2-6 weeks post-weaning, similar presentation to Lawsonians. Last 7-10 days but some become chronic.
No diagnosis but want to rule out Lawsonians on PM
Stephanurus dentatus
kidney worm, earthworm intermediate host
Diagnosis on urinalysis. The parasites are often in or near the kidney, in the ureters, or in perirenal fat. Posterior ataxia or paralysis can occur due to larvae migrating along the spinal cord. Diagnosis is usually made on necropsy of by finding ova in the urine.
Streptococcus suis
Infections usually affect nursing or recently weaned pigs. Clinical signs can be associated with polyarthritis, bronchopneumonia, sepsis, or meningitis. Morbidity and mortality vary greatly and are improved with treatment.
Stronguloides ransomi
threadworm in pigs, transmitted in colostrum, susceptible to ivermectin and benzimidazoles.
Reside in the small intestine of suckling piglets. Pigs may not show any clinical signs with only light infections. Heavy infection can cause diarrhea, anemia, emaciation, and death. Diagnosis can be made by fecal flotation, by an intestinal mucosal scraping, or necropsy.
Swine Pox
1-2 cm round papules, pustules, vesicles, and scabs on the ventral abdomen. Young and growing pigs most severely affected. Often transmitted by biting insects, particularly lice. Usually does not require treatment, unless lesions become secondarily infected.
Transmissible Gastroenteritis
Coronavirus
Trichinella spiralis
ingestion of encysted larvae in muscle (rodents, raw garbage, or cannibalism). Worm can infect most mammals. Humans can get infection from eating inadequately cooked pork.
Trichuris suis
whipworm found in the cecum and large intestine, clinical signs of loose stool with mucous and some blood in finishing pigs. Causes hemorrhagic to mucohemorrhagic enteritis. Susceptible to avermectin or piperazine.
Vesicular exanthema
also affects sea lions
Currently only a concern among California pig farms, indistinguishable fro FMD and Vesicular stomatitis
Transmission from seafood, once on farm, transmission via pig to pig contact
Vesicular stomatitis
Rhabdovirus, infects insects, cattle, horses and pigs.
Clinically indifferent from FMD
No treatment, rely on biosecurity
Vitamin A deficiency
A shortage in the diet can lead to head tilt, incoordination, reduced weight gains, and weak rear limbs in young pigs, especially an increase in middle ear infections, as also seen in turtles. In sows, it can cause embryonic mortality and congenital defects in their offspring.
Zearalenone
Mycotoxin that can be found in feed. Causes prolonged heat cycles due to high estrogens and is most common cause of cystic ovarian disease.
