Chapter 16

Classic shape of Campylobacter

Comma-shaped, “seagull wing,” spiral rods

Gram reaction of Campylobacter

Gram-negative

Is Campylobacter motile?

Yes, highly motile; darting corkscrew motion

Type of shape of Campylobacter

Helical, curved, pleomorphic; paired forms look like gull wings

Clinical signs of Campylobacter in animals

Diarrhea (sometimes bloody), fever, abdominal pain, infertility, abortion in cattle

Clinical signs of Campylobacter in humans

Vomiting, diarrhea (bloody), fever, abdominal pain; may be asymptomatic

Treatment for Campylobacter

Antibiotics and supportive fluids

Does Campylobacter grow at 37°C?

It grows at room temperature; does not grow at 42°C; 37°C is possible but not optimal for all species

What signs does Helicobacter cause?

Gastritis, vomiting, melena, “coffee-ground” vomit, anemia; may develop ulcers; many animals asymptomatic

Why is Helicobacter important in human medicine?

H. pylori discovered as major cause of gastric ulcers and stomach cancer; changed ulcer treatment

Animal species affected by Helicobacter

Dogs, cats, ferrets, humans

What do we see in ferrets with Helicobacter?

Ulcers, anorexia, teeth grinding, melena, dehydration; possible sudden death from perforation

What is Helicobacter linked to in dogs and cats?

Gastritis, vomiting; H. heilmannii linked to gastric lymphoma

Why does stomach pH matter in Helicobacter infections?

High acid → ulcers; Low acid → gastric cancer risk

How do we diagnose Helicobacter?

Endoscopic gastric biopsy, impression smear, culture; urease-positive testing

Animals affected by Lawsonia intracellularis

Pigs, hamsters, horses (not zoonotic)

Is Lawsonia intracellularis zoonotic?

No, not zoonotic

How is Lawsonia transmitted?

Fecal-oral route

Lesions in pigs (acute form)

Thickened ileum, hemorrhage, bloody diarrhea, dehydration, anemia, shock

Lesions in pigs (chronic form)

Mild diarrhea, poor weight gain for 4–6 weeks

Signs in hamsters with Lawsonia

Wet tail: diarrhea, dehydration, rapid weight loss, thickened intestines

Treatment for Lawsonia

Antibiotics, IV fluids, nutritional support, plasma transfusion (severe)

Is there a Lawsonia vaccine?

Yes, available for pigs

Stain used to identify Lawsonia

Warthin-Starry silver stain (deep brown)

Shape of Leptospira

Thin, tightly coiled spiral rods

Gram reaction of Leptospira

Gram-negative (stains poorly)

Is Leptospira motile?

Yes, highly motile with internal flagella

Where is Leptospira found?

Urine of infected wildlife; contaminated ponds, streams, puddles; survives in water for weeks–months

How do we diagnose Leptospira?

Serology (titers), fluorescent antibody testing, dark-field microscopy; culture difficult

How does Leptospira cause disease?

Enters skin/mucosa → bloodstream → kidneys, liver, spleen, CNS → organ failure

What are serovars?

Different antigenic varieties; vaccines are serovar-specific; no cross-protection between many

Wildlife reservoirs for Leptospira

Raccoons, skunks, rodents, feral swine; water sources

What does Leptospira cause in dogs?

Vomiting, diarrhea, PU/PD, icterus, lethargy, dehydration; kidney/liver failure; some become carriers

Is Leptospira zoonotic?

Yes — major zoonotic pathogen; waterborne outbreaks common

Is there a Leptospira vaccine?

Yes — canine vaccine for serovars Canicola, Grippotyphosa, Icterohaemorrhagiae, Pomona

What is the problem with the Leptospira vaccine?

Limited cross-protection; higher risk of reactions; does not cover Autumnalis

Clinical signs of Leptospira in cattle

Abortion, stillbirth, decreased milk; calves: renal signs, dehydration, fever, icterus

Tests for Leptospira

Serology, FA testing, dark-field microscopy; urine morphology preserved with formalin

Can we culture Leptospira?

Very difficult; requires special conditions; dark-field microscopy preferredand may not yield successful results.

Shape of Borrelia

Loosely coiled spirochete

Size of Borrelia

Very small; cannot be seen with standard light microscopy

Is Borrelia motile?

Yes; highly motile with internal flagella bundles

Vector for Borrelia

Ixodes scapularis and Ixodes pacificus ticks

Stages of Lyme disease in humans

Localized rash → early disseminated disease → chronic disseminated disease

Tick attachment time for transmission

24–48 hours

Clinical signs in dogs with Lyme disease

Shifting-leg lameness, fever, lethargy, anorexia, lymph node enlargement; kidney signs rare

Testing for Lyme disease

Initial ELISA or IFA, confirmed with Western Blot

Treatment for Borrelia infection

28-day doxycycline; amoxicillin if GI upset; early treatment prevents long-term damage