Mycoplasma

Question 1

Characteristics

Answer 1

No cell wall
Fastidious bacteria - require a rich growth medium containing serum (difficult to isolate)

Question 2

Habitat

Answer 2

Mucous membranes

Question 3

Effects

Answer 3

On respiratory(most common), arthritis or genitourinary tract disease

Question 4

Important disease in poultry

Answer 4

MG - Mycoplasma gallisepticum

Causes Pleuropneumonia–like Organism (PPLO) infection, chronic respiratory disease, infectious sinusitis

Question 5

Important disease in SWINE

Answer 5

M. hyopneumoniae

Causes porcine enzootic pneumonia

Question 6

Colony morphology

Answer 6

Use dissecting microscope, no stain***

Fried egg and dense Centre

Question 7

Mycoplasma gallisepticum infection

Culture condition

Answer 7

Mycoplasma medium/agar
- In enriched broth medium containing 10-15% serum (have antibody against the bact) and antibiotics (to suppress other bact growth (penicilin or ampiciliin)
- Incubation at pH 37C, 4-5 days

Question 8

Mycoplasma gallisepticum

Transmission & Epidemiology

Answer 8

Through eggs

Dormant in infected chick for days to months, only developed and showed clinical signs when stressed, through aerosol

Once infected, become carrier

Question 9

Mycoplasma gallisepticum infection

Site of infection

Answer 9

Epithelium of the upper air passages

Also in lower respiratory tract (severe and acute cases)

Question 10

Mycoplasma gallisepticum infection

Clinical and post mortem findings

Answer 10

Respiratory distress (can observe) , mild sinusitis & tracheitis (do pm)
High morbidity and low mortality
Nasal and eye discharge
Low egg production rate
Reduce weigh gain***
Airsacculitis (severe air sac thickening and turbid, with exudative accumulations), fibrinopurulent pericarditis,
and perihepatitis

Question 11

Mycoplasma gallisepticum infection

Treatment

Answer 11

Antibody
- chlortetracycline, erythromycin, oxytetracycline, or a fluoroquinolone such as enrofloxacin.
- in feed or water for 5-7 days

Maintain seronegative stock in breeders

Vaccine
- consists of a mild strain of M. gallisepticum (F-strain)
- usually given at ~10-14 week of age, only in layers or parent stocks .

Question 12

Mycoplasma hyopneumoniae

porcine enzootic pneumonia
General facts

Answer 12

High morbidity and low mortality

Commonly complicated by other opportunistic bacterial or viral infection (secondary)

Question 13

Mycoplasma hyopneumoniae

Clinical signs

Answer 13

Pneumonia
Sporadic dry nonproductive cough
Fever, dyspnea(difficulty in breathing) and impaired growth

Question 14

Mycoplasma hyopneumoniae

Transmission

Answer 14

• Transmitted from older to younger pigs by contact
• Mechanical transmission by man or other animals
• spread on the wind for
  several miles

Question 15

Mycoplasma hyopneumoniae
porcine enzootic pneumonia

Virulence factor and function

Answer 15

cytadhesin (protein)

Attaches to cilia of resp. epithelial cells, resulting in damage to and subsequent loss of cilia

Question 16

Mycoplasma hyopneumoniae
porcine enzootic pneumonia

PM lesions

Answer 16

Typical lesion are located in the apical and cardiac lobes of the lung, and consist of well-demarcated, dark red to purple areas in acute disease, or tan to gray areas in chronic disease.

Question 17

Mycoplasma hyopneumoniae
porcine enzootic pneumonia

Prevention, treatment & control

Answer 17

• Selection of stock from herd free (serological test)
• Continual antimicrobial therapy with tylosin, chlortetracycline, or
  lincomycin.
• Optimizing environmental conditions (air, ventilation, temperature)**
• All-in/all-out pig flow

Question 18

Mycoplasmosis

Answer 18

Diene’s stain - mycoplasma colony retain blue color

Serology - ELISA
PCR - detect in urt