Pig Diseases Flashcards
HIGH morbidity, LOW mortality – concurrent illness exacerbates disease ▪ Uncomplicated infection: short course, low mortality
o Lethargy, resp illness, high fever, prostration, coughing, anorexia, conjunctivitis, oculonasal discharge o IMPORTANT: dz in pigs/waterfowl can mutate – be major zoonotic problem
Swine Influenza
ALL age groups – nearly 100% mortality in piglets <1wk old
No other dz spreads so rapidly or causes such high mortality – seldom die if >1month
Watery diarrhea, vomiting, wet/dirty appearance to litter from profuse diarrhea
Tx: symptomatic
Prevention: feed feces and intestinal contents from infected piglets to sows who are >14 days from farrowing
Porcine Epidemic Diarrhea and Transmissible Gastroenteritis (TGE) – coronavirus
Piglets <4 weeks old o Vomiting and wasting disease (VWD) and encephalitic forms
Hemagglutinating Encephalomyelitis Virus (HEV)
STILLBORN PIGS – most common cause o 3 overlapping syndromes – affects ALL ages
▪ Repro impairment/failure – abortions, mummies, stillbirths, early embryonic death ▪ Resp Disease – wean pigs get cough (thumps), purple ear tips from vasculitis
● Nursery pigs – interstitial pneumonia ▪ High pre-weaning mortality – diarrhea, recurrent fevers
Tx: NONE – may have to depopulate or close herd and follow titers
Prevention: vaccine
PRRS – Porcine Respiratory and Reproductive Syndrome – arterivirus
5 days old – often in association w/ E. coli
Rotavirus
Aka blue eye paramyxovirus
Blueye – tublavirus
REPORTABLE – US is currently free of this
Closely related to pestivirus – BVD, border disease virus o Virus affects stem cells in bone marrow neutropenia, thrombocytopenia – become immune suppressed and
susceptible to enteric bacterial infections
Oral ulceration, vomit, diarrhea, oral petechiation, paresis/paralysis, fever, shivering, conjunctivitis
Can cross placenta – repro failure – severe systemic infection and abortion
Hog Cholera – togavirus (Classical Swine Fever)
Fever, inappetence, hemorrhage of ear skin, acute death
DDx: classical swine fever, erysipelas
45
carried by warthogs, transmitted by soft ticks
Necropsy: petechial hemorrhages on internal organs
African Swine Fever
Swine and sea lions/seals/marine mammals o Sea lions off coast of CA – not present in US pigs o REPORTABLE
Vesicular Exanthema – calicivirus (aka San Miguel Sea Lion Disease in sea lions)
PIG – primary host
▪ Erradicated from pigs in US, can devastate non-immune herd ▪ Resp, repro, CNS (not GI) – clinical signs depend on age group
● Young neonates <3wks: NEURO, CNS signs, tremors, incoordination, blindness, opisthotonos,
hypersalivation, ataxia, nystagmus, paddling, DEATH 100% mortality
o DDx for tremors: organophosphates, circovirus, hog cholera, NOT PRRS o Some are born mummified
● Wean pigs: NEURO and RESP – similar signs as young neonates + resp signs, lower mortality ● Grower/Finisher pigs: RESP – cough, sneezing, nasal discharge ● Older pigs at breeding age: resp signs, REPRO FAILURE (abortion, resorption, mummification)
o Ruminants
▪ 1st sign = paresthesia (MAD ITCH) at inoculation site, ataxia, proprioceptive deficits, circling, nystagmus,
strabismus – sometimes see aggression, depression death in 2 days
● Often have pigs housed nearby – pigs are 1˚ host!
● NO TREATMENT – animals die, prevention = remove the pigs
● DDx for clinical signs: rabies (Negri bodies), Polioencephalomalacia, salt poisoning, lead
poisoning, hypomagnesemia, meningitis
o Horses
▪ VERY RARE – depression, inability to swallow
o NO TREATMENT – older pigs recover on their own prevent w/ vaccination
Pseudorabies – herpesvirus (Aujesky’s Disease)
Peudorabies
Herpesvirus
TGE
Coronavirus
PRRS
Arteivirus
BRED SOW RETURNS TO HEAT – embryo resorption, unapparent infection in sow
▪ Mummified fetus, weak piglets, small litters, stillbirths ▪ Abortions – RARE – endometrium is not affected so no PGF2a released
o VACCINATE o DDx for fetal loss: parvo, toxoplasma, brucella, pseudorabies, PRRS, eperythrozoonosis, erysipelas, lepto
Parvovirus
G-, curved bacteria in enterocytes – proliferative enteropathies
▪ Aka Porcine Proliferative Enteritis – FINISHING PIGS (40-80lb)
o Soft buttery (yellow) stool, sometimes acute hemorrhagic diarrhea, gradual wasting, lethargy o Common – weaned and older pigs – persistent diarrhea, weight loss (similar to Johne’s in cows) o Necropsy: thickened inflamed ileum – proliferative ileitis w/ edematous mesentery
Lawsonia intracellularis
Porcine Proliferative Enteritis
Lawsonia intracellularis
Mucohemorrhagic diarrhea – large bowel diarrhea, fibrinonecrotic typhlitis and colitis
▪ Small intestine unaffected
o Bloody diarrhea and death – grower/finisher pigs
Serpulina/Brachyspira hyodysenteriae – SWINE DYSENTERY
SWINE DYSENTERY
Serpulina/Brachyspira hyodysenteriae
RECTAL STRICTURES w/ chronic infection, “button” ulcers in large intestine
WEANERS and GROWERS – uncommon in piglets (passive immunity from colostrum)
Salmonella
3 Forms – GROWER and FINISHERS pigs
▪ Peracute – pigs found suddenly dead ▪ Acute – pigs are lethargic, painful in joints, anorexia, develop diamond skin lesions ▪ Chronic – arthritis progresses to vertebral joints and limbs joints may fuse – painful swollen joints
o Lesions: red/purple skin lesions in diamond shapes
Erysipelothrix rhusiopathiae – DIAMOND SKIN DISEASE
Enterotoxigenic E. Coli
Enteric colibacillosis- nursing
EDEMA DISEASE- weaned
Lesions: edema, pericardial/pleural effusion (Shiga toxin 2e) – destroys endothelial cells in vessels blood clots,
hemorrhage, ischemia necrosis, edema of vital organs (including brain)
Enterotoxigenic E. Coli – Enteric colibacillosis, EDEMA DISEASE
Most common cause of diarrhea in NURSING piglets (<5 days old) – piglets huddled and shivering ▪ See w/ rotavirus – watery diarrhea, dehydration, acidosis, death ▪ Prevention: vaccinate, NEVER MIX PIGS OF DIFFERENT AGES TOGETHER
F18 - shigatoxin
Enteric colibacillosis
FATAL dz of rapidly growing WEANED pigs – pigs on high protein, high energy diet ▪ Fever, anorexia, SQ emphysema, dyspnea, open mouth breathing, convulsions, diarrhea, swollen eyelids
(eyelid edema, forehead, lips), circling, acute death
F 18 Shiga toxin
Edema Disease
ABORTION – any stage of gestation – placentas and aborted fetuses have NO GROSS LESIONS
Transmission: venereal, aborted fetuses
ZOONOTIC – highly pathogenic in humans!!
Brucellosis
Mycobacterium avium
swine tuberculosis
NURSING and WEANED pigs – polyarthritis, bronchopneumonia, sepsis, meningitis (NOT colitis)
Varying morbidity/mortality – improved w/ tx
Streptococcus suis
Clostridium perfringens type C
hemorrhagic/necrotic enteritis- 1-5 days old
1-5 days old
Vaccinate sows
Diagnosis: lesions, bacterial isolation, typing
Acute outbreaks: type c antitoxin to piglets, can give antibiotics
Clostridium perfringens type C – hemorrhagic/necrotic enteritis
VERY UNCOMMON IN PIGS – no effective drugs
Cryptosporidium parvum
5-21 days old -diarrhea
Rotavirus
Diarrhea in unweaned pigs, double circle in egg shed in feces
Isospora suis
Can effect all ages but usually in older pigs, found in feces
Trichuris suis
Housing stress, type of feed, concurrent disease
Common in GROWING SWINE – pale MM, dark feces
Necropsy: clotted blood in stomach (pars esophagea portion) and duodenum
Gastric Ulcers
OESOPHAGOSTOMUM infection – vomiting w/o diarrhea
▪ Tachycardia, restlessness, colic signs
Intussusception
Inguinal MALES after castration, heritable!
Umbilical FEMALES
Hernias
12-14 week older pigs – unknown etiology, possibly heritable
Raised circular lesions on ventral abdomen – NO TREATMENT NEEDED – resolves on its own
Pityriasis rosea
Exudative epidermatitis – aka GREASY PIG DISEASE (scabs, excoriations)
Piglets <8wks old – brown exudative spots on skin of head, axillae, groin – brown, crusty
Morbidity/mortality high in younger pigs, rarely affects adults
Bacterial culture
Tx- antibiotics in older, cull in younger
Staphylococcus hyicus
Poxvirus
Swine pox
Transmitted by biting insects (esp. lice!) – control is eliminate hog lice/insect vectors o 1-2cm round papules, pustules, vesicles, scabs on ventral abdomen
Swine pox, poxvirus
Caused by bites from pen-mates or from violent head-shaking (from mites/lice in ear)
Aural hematoma
Semi-lethal hereditary defect: causes macules and papillomas around coronary band
Dermatosis vegetans
Zinc Deficiency! Supplement zinc in diet
▪ Starter diet = 125 ppm zinc + 0.9% Ca
▪ Grower diet = 75 ppm zinc + 0.6% Ca
▪ Finisher diet = 50 ppm zinc + 0.5% Ca
May resemble “greasy pig disease” (Staph hyicus) which is seen more in younger suckling pigs, tx = abx
Parakeratosis
Snorting, sneezing, snuffling, coughing, epistaxis, nasal discharge, turbinate atrophy, facial distortion
Common in piglets: 3-8 weeks old
Tx: antibiotics / Prevention: vaccination
Atrophic Rhinitis – Bordetella bronchisepticum (nonprogressive), Pasteurella multocida (progressive)
Snout necrosis when it enters nasal/oral mucosa
Necrotic Rhinitis – Fusobacterium necrophorum (G+)
Necrotic Rhinitis
Fusobacterium necrophorum (G+)
Mycoplasma hyopneumoniae
ENZOOTIC PNEUMONIA
Coughing in feeder pigs (persistent dry cough, fever, inappetence, ↓ weight gain/retarded growth
Necropsy: purple/grey consolidation in cranioventral lungs with catarrhal exudate in airways
Prevention: vaccination, address air quality and ventilation
Dx: lesions and PCR assay
Mycoplasma hyopneumoniae – ENZOOTIC PNEUMONIA
ACTINOBACILLUS PLEUROPNEUMONIAE (G-)
Pleuropneumonia
High morbidity and mortality
Sudden onset respiratory distress w/ open mouth breathing, frothy pink oral/nasal discharge (blood) o Pigs <6 months old who commonly have concurrent infections (Mycoplasma, Pasteurella, PRRS, influenza)
Dx - bacterial culture
▪ DDx – influenza affects ALL ages, no pink discharge o Necropsy: fibrinonecrotic hemorrhagic lung lesions
▪ Necrohemorrhagic fibrinosuppurative pleuropneumonia
Adults get bloody, dark lungs
Tx with antibiotics
Control at elimination of bacterial at breeding stock level
Pleuropneumonia – ACTINOBACILLUS PLEUROPNEUMONIAE (G-)
DDx for lameness
DDx for lameness: Strep suis, Erysipelas, Mycoplasma hyorhinis, Haemophilus parasuis
Multiple pigs from herd present lame – usually fast growing well-muscled pigs, lame at 4-8 months old
Lesion: defects in articular cartilage – medial femoral condyle, humeral condyle, humeral head, glenoid of scapula,
distal ulna, lumbar vertebrae
Cull affected animals – replace w/ normal animals for breeding - Cross Breeding DOES NOT HELP
Tx: symptomatic, doesn’t cure dz
Osteochondrosis dessicans
Painful joints, pneumonia, sometimes neuro – swollen painful joints, shifting leg lameness
Affects pigs 2-4 months old
Necropsy: fibrinopurulent pleuritis and peritonitis (polyserositis), sometimes pericarditis/meningitis o Tx: penicillin
Glaesserella parasuis – GLASSER’S DISEASE
Presents similar to Glasser’s Disease – polyarthritis, polyserositis, fever, pneumonia, 2-4 month old pigs
LOW mortality
Mycoplasma hyorhinis
