Inf. diseases II - Swine diseases (diarrhea 1/2) Flashcards
Primary bacterial causes of swine diarrhea. (6)
e. coli
salmonella spp.
clostridium perfringens
brachispyra hyodysentery
lawsonia intracellularis (ileitis)
brachispyra pilosicoli
Primary viral causes of swine diarrhea. (3)
T.G.E. (transmissible gastroenteritis(corona))
rotavirus
circovirus (PCVII)
Primary protozoal causes of swine diarrhea. (2)
coccidia
balantidium coli (ciliated protozoan)
Primary parasitic causes of swine diarrhea. (2)
ascaris suum (round worms)
*esophagostomum
e.coli can cause what two types of disease:
edema disease (ED)
postweaning diarrhea (PWD)
EDEMA DISEASE (ED) is a disease of
weaner and grower pigs,
caused by E. coli,
characterized by subcutaneous and sub-serosal edema, progressive ataxia, recumbency and death.
EDEMA DISEASE (ED) is a disease of weaner and grower pigs, caused by E. coli, characterized by (4)
subcutaneous and sub-serosal edema, progressive ataxia,
recumbency and death.
ED and PWD can occur separately or at the same time
POSTWEANING DIARRHEA (PWD) is a disease of the
post weaning period,
caused by E. coli,
characterized by diarrhea, dehydration and often death.
POSTWEANING DIARRHEA (PWD) is a disease of post weaning period, caused by E. coli, characterized by (3)
diarrhea, dehydration and often death.
ED and PWD can occur separately or at the same time.
Edema disease strains of e.coli produce what
verocytotoxins
These destroy the walls of blood vessels.
Strains: O138, O139, O141
Postweaning disease is caused by
A specific serotype of enterotoxigenic E. coli
Strains: O8, O141, O147, O149, O157
ED and PWD target demographics
ED: 4-12 week weaners
PWD: 3-10 days after weaning
Morbidity of ED and PWD.
ED: morb 50%
PWD: morb 80-90%
Mortality rate of ED and PWD.
ED: mort. almost 100%
PWD: mort. 30%
Which one spreads between pens, ED or PWD.
ED: Does not spread to others pens in the same farm.
PWD: Does spread to other pens in the same farm (within a short period).
ED frequently occurs at what stage?
Sporadic dz
Frequently occurs within 1 week after the change of diet, weaning, vaccination, pen change, regrouping.
(PWD on the other hand is an endemic dz)
ED: Outbreak duration average
8 days (<15 days)
Transmission of ED and PWD.
Excretion: feces
Ingestion
Route: fecal-oral
Clinical signs of ED. (3)
Incoordination of the hindlimbs, falling (CNS signs due to cranial pressure) – earliest and most obvious sign!
Edema of eyelids and conjunctiva, face is next.
Death in 6-36 hours.
Clinical signs of PWD. (5)
Sudden death of one or two pigs in good condition.
Severe diarrhea – watery and yellow
Fever, dehydration
Anorexia, weight loss
Death in a few days.
Post mortem signs of ED. (3)
Facial edema
Full stomach
Mesenteric edema
NOTE:This is the only disease with both neuro signs as well as mesenteric edema.
Post mortem signs of PWD. (4)
Dehydration
Serofibrinous peritonitis
Fluid-filled intestines
Mesenteric edema
Material for diagnosis of ED and PWD. (2)
Feces
Biopsy (intestines, mesenteric LNs)
Lab analyses for diagnosis of ED and PWD. (2)
Bacteriology – isolation of E. coli
Histology
Treatment for ED.
no Tx
Toxins already in bloodstream and there is no effective Tx.
Treatment for PWD. (3)
antimicrobials (5-7 days)
ABs in water (or food)
Electrolytes
Prevention of ED and PWD. (4)
Good animal husbandry & minimized stress.
Diet: less protein (21%->17%), more fiber
Feeding probiotics
Good vaccination schedule
Name 2 types of spirochetoses to affect swine more commonly.
swine dysentery (Brachyspira hyodysenteriae)
porcine colonic spirochetosis (Brachyspira pilosicoli)
SWINE DYSENTERY (SD) is a disease of
growing pigs,
caused by Brachyspira hyodysenteriae, characterized by mucohemorrhagic diarrhea.
SWINE DYSENTERY (SD) is a disease of growing pigs, caused by
Brachyspira hyodysenteriae,
characterized by mucohemorrhagic diarrhea.
SWINE DYSENTERY (SD) is a disease of growing pigs, caused by Brachyspira hyodysenteriae, characterized by
mucohemorrhagic diarrhea.
Causative agent of swine dysentery.
Brachyspira hyodysenteriae
Previously known as Serpulina hyodysenteriae
Gram–, anaerobic, beta-hemolytic spirochete
Brachyspira hyodysenteriae survives in what conditions? Eliminated by?
Survives in feces
< 48 days at 0-10°C
7 days at 25°C
24h at 37°C
Eliminated by drying and disinfection.
Phenolic and sodium hypochlorite disinfectants are most effective.
Swine dysentery is most common in what age group?
Most common in 7-16-week-old age group, may also affect older and adult pigs.
Describe the spread of swine dysentery.
Spread within group is slow (7-14 days), may spread to other pens of pigs over a 2-3 week period.
Tends to be persistent in herds, has cyclic occurrence (3-4 week cycle).
Morbidity of swine dysentery.
Morbidity 10-75%
Mortality of swine dysentery.
Mortality <50% (if not treated)
Transmission of swine dysentery.
Excretion: feces
Direct contact:
Fomites
Ingestion
Route: fecal-oral
Swine dysentery sheds for how long? Carriers?
Recovered pigs can become carriers -> shedding of the organism for 50-90 days.
IP of swine dysentery
average 10-14 days (2 days to 3 months)
Clinical signs of swine dysentery
Depression
Loss of appetite
Moderate fever
Mucohemorrhagic diarrhea
Blood in feces 2-3 days after the initial onset.
Death is due dehydration and toxemia.
Some days to weeks after initial onset of signs
Recovery in 3-4 weeks if not treated
Post mortem lesions characteristic to swine dysentery. (4)
Weight loss, dehydration
Colitis and typhlitis (Typhlitis is an inflammation of the cecum)
Material for diagnosis of swine dysentery. (1)
swab from colon
Lab analyses for diagnosis of swine dysentery. (3)
Isolation of organism in culture
Histology
Serology (ELISA)
Tx for swine dysentery.
ABs
E.g. macrolides (tylosin, lyncomycin)
Mass medication of affected group by
Treatment by water.
Prevention of swine dysentery.
Good biosecurity and animal husbandry.
Options for Eradication of swine dysentery from herd by (3)
Test & slaughter
Stamping out
Partial stamping out and treatment
Typical target demo for Porcine colonic spirochetosis. At what life stage?
Pigs 4-12 week of age, typically 7-14 days after weaning
Clinical signs of Porcine colonic spirochetosis
mucoid non-bloody diarrhea, reduced feed conversion, depression and reduced growth rate
Death is rare
Diagnosis of Porcine colonic spirochetosis.
Histology: dense mat or false brush border of spirochete cells attached to the colonic epithelium.
Porcine proliferative enteritis is also known as….? (3)
Porcine Intestinal adenomatosis
Proliferative hemorrhagic enteropathy
Ileitis
PORCINE PROLIFERATIVE ENTERITIS (PPE) is an enteric disease of
growing-finishing and young breeding pigs, caused by Lawsonia intracellularis.
PORCINE PROLIFERATIVE ENTERITIS (PPE) is an enteric disease of growing-finishing and young breeding pigs, caused by
Lawsonia intracellularis.
Describe Lawsonia intracellularis. (4)
Obligate intracellular, Gram– rod
Bacteria is free in the cytoplasm of the affected enterocytes.
Pathogenesis of Porcine proliferative enteritis
hyperplasia of epithelial cells of the intestinal crypts (ileum and colon)
This is reversible
Survival of Lawsonia intracellularis in the environment.
Can survive in +5°C environment for 2 weeks.
Host range for Lawsonia intracellularis. (4)
horses, sheep, dogs, emus and ostriches
Reservoir: birds and rodents
Lawsonia intracellularis commonly affects what age of pig?
Most commonly affects 12-20 week old growing pigs.
Predisposed: large white pigs (Landrace, Estonian large white and Duroc).
Reservoir: birds and rodents
Porcine proliferative enteritis trends in what manner? (2)
Sporadic disease all year around
Self-limiting (about 10 weeks)
Morbidity of Porcine proliferative enteritis.
Morbidity
Herd morbidity 20-75% (<100%)
Morbidity in herds 5-20% (gilts <50%)
Mortality of Porcine proliferative enteritis.
Mortality <10%
Transmission of Porcine proliferative enteritis.
Excretion: feces. Up to 10 weeks
Ingestion
Route: fecal-oral transmission
IP of Porcine proliferative enteritis.
2-3 weeks
4 forms of Porcine proliferative enteritis:
porcine intestinal adenomatosis (PIA),
porcine hemorrhagic enteritis (PHE),
necrotic enteritis (NE) and
subclinical ileitis
Describe the porcine intestinal adenomatosis (PIA) form of Porcine proliferative enteritis.
affects pigs aged 6-20 weeks
no diarrhea, mortality low
post mortem: thickened ileal wall
Describe the porcine hemorrhagic enteritis (PHE) form of Porcine proliferative enteritis.
affects pigs aged over 28 weeks old
diarrhea is dark-red or black
mortality is increased
post mortem: blood clots in ileal lumen
Describe the necrotic enteritis (NE) form of Porcine proliferative enteritis.
affects post-weaning aged pigs
diarrhea normal colored
mortality is increased
is one of the most common forms of porcine proliferative enteritis
Describe the subclinical ileitis form of Porcine proliferative enteritis.
affects post-weaning aged pigs
diarrhea normal colored
mortality is normal
is one of the most common forms of porcine proliferative enteritis
General clinical signs of Porcine proliferative enteritis. (4)
Reduction in growth rate
Fever
Weight loss
Diarrhea
Only the hemorrhagic form includes hematochezia and quick death.
Post mortem signs of Porcine proliferative enteritis.
Thickened ileal wall
Hemorrhagic enteritis (blood clots) – PHE!
Material for diagnosis of Porcine proliferative enteritis. (2)
fecal matter
biopsy (ileum)
Lab diagnoses for diagnosis of Porcine proliferative enteritis. (4)
Hard to cultivate (requires cell culture)
PCR (Sensitivity of the method is not ideal.
Positive results are only present in animals with active lesions)
Serology (ELISA)
Histology
Tx of Porcine proliferative enteritis.
ABs: Lincomycin, macrolides
Treat the whole herd, not just the sick!
Prevention of Porcine proliferative enteritis. (2-3)
Good biosecurity and animal husbandry.
Vaccination
In Estonia: Enterosol Ileitis – PO
