Unit 5 - Asporogenous Gram Positive Rods (Cram 1/2)

Which two asporogenous bacteria must be stained with acid fast?

1. Nocardia

2. Mycobacterium

What is the bacterial morphology of Listeria?

Small coccoid rods in chains

What are the cultural characteristics of Listeria?

Grow in a wide temperature range, small, smooth, and transparent colonies, tumbling motility in 2–4 hour old broth

What climate do Listeria bacteria prefer?

Cold or tempered climates

Where in the environment can Listeria be isolated from?

Soil, plants, decaying vegetation, and silage

What four conditions does Listeria monocytogenes cause in ruminants?

1. Encephalitis (neural form)

2. Abortion

3. Septicemia

4. Endophthalmitis (ocular form)

What condition does Listeria monocytogenes cause in cattle?

Mastitis (rare)

What two conditions does Listeria monocytogenes cause in dogs, cats, and horses?

1. Encephalitis (rare)

2. Abortion

What three conditions does Listeria monocytogenes cause in pigs?

1. Abortion

2. Septicemia

3. Endophthalmitis

What condition does Listeria monocytogenes cause in birds?

Septicemia

What is the name for the condition caused by Listeria monocytogenes when it effects the young of many species, and causes necrotic foci in the liver and other organs?

Visceral/ septicemic Listeriosis

What disease is caused by Listeria monocytogenes and results in inflammation and tiny abscesses of the brain, spinal cord, and meninges?

Meningoencephalitis/Circling Disease

What is the source of infection for meningoencephalitis?

Contaminated, moldy silage

What are the six clinical signs of meningoencephalitis?

1. Paralysis of the ear, eye, and jaw muscles

2. Head pressing

3. Animal may crowd in the corner

4. Circling movements

5. Convulsions

6. Death

Which Listeria effects sheep and cattle and causes abortion?

Listeria ivanovii

Which Listeria effects sheep and causes a rare meningoencephalitis?

Listeria innocua

When doing a post mortem on a suspected meningoencephalitis case, lesions in which four organs should be samples?

1. Liver

2. Kidney

3. Spleen

4. Central nervous system

What are two treatments for a Listeria monocytogenes infection?

1. Penicillin

2. Good silage

Is Listeria monocytogenes zoonotic?

Yes, but rarely

What percent of healthy pigs may be carriers of Erysipelas?

Up to 50%

What is the bacterial morphology of Erysipelas bacteria?

Slender rods or short filaments

What are the two serotypes of Erysipelas bacteria?

1. Smooth colonies = acute infection

2. Rough colonies = chronic infection

How do humans get Erysipelas infections?

Fish

What bacteria causes diamond skin disease in pigs?

Erysipelothrix rhusiopathiae

What three conditions does Erysipelothrix rhusiopathiae cause in pigs?

1. Chronic erysipelas

2. Acute septicemia

3. Diamond skin disease

What age of pigs does acute septicemia cause by Erysipelothrix rhusiopathiae effect?

Suckling piglets

Why is chronic erysipelas referred to as a sequelae to acute septicemia?

This means that piglets that survived the acute form may develop this chronic form

What three symptoms does chronic erysipelas caused by Erysipelothrix rhusiopathiae cause?

1. Cardiac dysfunction

2. Arthritis

3. Reduced farrowing rates

How do you determine if a pig has diamond skin disease if no diamond shaped lesions appear?

Improvement with penicillin within 24 hours

What condition does Erysipelothrix rhusiopathiae cause in lambs?

Non–suppurative polyarthritis

What condition does Erysipelothrix rhusiopathiae cause in sheep?

Post–dipping lameness

What condition does Erysipelothrix rhusiopathiae cause in turkeys?

Turkey erysipelas

Why do turkey farmers test their tom's semen before artificial insemination?

Toms can excrete turkey erysipelas in their semen and hens can die within 5 days if artificially inseminated with it

What is the condition of lesions on the human hand caused by Erysipelothrix rhusiopathiae called?

Erysipeloid

What is the bacterial morphology of Corynebacteria?

Small, pleomorphic, irregular rods, palisades, may be clubbed at one or both ends

What are the cultural characteristics of Corynebacteria?

Small, whitish colonies, beta hemolysis

What is the habitat of Corynebacteria?

Manure, and skin and mucous membranes (without causing disease)

What is the main symptom of a Corynebacteria infection?

Pyogenic (large amounts of foul smelling pus)

What bacteria causes CL disease?

Corynebacterium pseudotuberculosis

What does CL disease stand for?

Caseous lymphadenitis

What does caseous mean?

Pus that is cheese–like

What are the two forms of caseous lymphadenitis?

1. Abscesses of the lymph nodes close to the skin surface

2. Abscesses in internal organs and internal lymph nodes

What two species does caseous lymphadenitis effect?

1. Sheep

2. Goats

In an animal with caseous lymphadenitis, how do the Corynebacterium pseudotuberculosis bacteria infect the lymph nodes?

When they are phagocytosed they are transported to nearby lymph nodes

What are the two ways caseous lymphadenitis is treated?

1. Cull infected animals

2. Prevention through hygiene/vaccination

What bacteria is spread through the prepuce (smegma) and semen of asymptomatic male cattle and pigs?

Corynebacterium renale

What two conditions does Corynebacterium renale cause in cattle and occasionally pigs?

1. Pyelonephritis

2. Cystitis

What is the layperson's term for a Corynebacterium renale infection in male sheep?

Pizzle rot

What kind of diet will predispose male sheep to pizzle rot?

High protein diet (causes prepuce ulcerations from increased ammonia)

What bacteria was previously known as Corynebacterium equi?

Rhodococcus equi

What are the cultural characteristics of Rhodococcus equi?

Mucoid, salmon colour colonies on blood agar plate

What disease is caused by a Rhodococcus equi infection in foals 2–4 months old?

Suppurative bronchopneumonia

What sounds will you hear when auscultating a foal with suppurative bronchopneumonia?

Loud, moist rales (rattling/whistling)

What procedure is preformed when diagnosing suppurative bronchopneumonia

Broncho alveolar lavage (BAL)