This document discusses Mycoplasma gallisepticum infection in poultry farms. Some key points: - M. gallisepticum is a highly successful pathogen that causes chronic respiratory disease in chickens and turkeys. Once infected, the infection remains for life. - It is transmitted both horizontally between flocks through contact/aerosols and vertically from parent to offspring through eggs. - Clinical signs include coughing, sneezing, and reduced egg production. Post-mortem lesions include sinusitis, tracheitis, and airsacculitis. - Diagnosis involves isolation of the bacteria or serological tests like ELISA. Treatment includes antibiotics like tetracyclines and tylos

1. MEMBER IN INTERNATIONAL NETWORK FOR POULTRY DEVELOPMENTFAO
FAO IRAQ
Prevalence of Mycoplasma gallisepticum
Infection in Poultry Farms
Dr. Majed H. Mohammed Ph.D.
Virology and Moleculat Cell Biology
majed.mohammed@uod.ac

2. Background
• Mycoplasmas are highly versatile and successful
pathogen
• Chronic Respiratory Disease: Once infected,
infection remains for life
• Mycoplasma lack a cell wall: resistant to
penicillin group of antibiotics
• Antimicoplasmal drugs are bacteriostatic
• Antibodies can not eliminate infection
• Field infection (MG/MS) level is high due to
vertical transmission and low level of biosecurity
• Raising mycoplasma clean flocks is not
practicable

3. Major pathogenic species
M. gallisepticum - Chickens, Turkeys
M. synoviae - Chickens, Turkeys
M. meliagridis - Turkeys
M. iowae - Turkeys
Smallest self replicating prokaryotes
Lack of cell wall, bounded by cell membrane
Fragile – easily killed out side its host by
disinfectants

4. • Costliest Disease in Poultry
• Mortality
• Reduced feed conversion
• Loss of weight
• Complications with – IB, ND, E coli
• Drop in egg production
• Reduced hatchability & chick viability
• Cost of eradication and control programs
Economic significance

5. Transmission
• Horizontal
– Within a flock - contact or aerosols
– Between flocks - windborne
• Vertical
– Parent to the chick through egg

6. Some possible egg-borne infections

7. Target organs:
– Respiratory system
– Synovial membranes
– Reproductive system
Incubation period:
– Chronic slow spreading
– Varies from 6-21 days

8. Clinical Signs
• Coughing, sneezing, Nasal discharge
• Foamy secretions in the eye
• Open mouthed breathing
• Tracheal rales
• Reduced feed consumption
• Loss of weight – more stunted chicks
• Drop in egg production – layer, breeder
• Reduced hatchability, chick viability
• Lameness
• Morbidity – up to 100%
• Mortality – up to 30%

9. Gross Lesions
• Sinusitis and conjunctivitis
• Tracheitis with excessive
mucus
• Airsacculitis
• Pneumonia
• Synovitis
• Osteomyelitis
• Salpingitis

10. The most characteristic signs in adult flocks
are tracheal rales, nasal discharge, coughing

11. Frothy exudate
in Air sac
Accumulation of
Cheesy mass in thoracic air sac

12. Foamy lesions
develop on air sacs
Within one weak later become 8-10 folds
thicker than normal

13. Secondary E.coli infection leads to severe
fibrinopurelent or Caseous exudates on
pericardium and liver capsule (fibrinous
pericarditis and fibrinous perihepatitis)

14. Complicated Chronic Respiratory Disease
Air-saculitis, Pericarditis, perihepatitis

15. Catarrhal inflammation of the nasal passages,
sinuses, trachea, and bronchi .

16. Diagnosis of maycoplasma
• Isolation: Laborious process (slow growth – complex
nutritional requirement) tubes should be incubated at 37 C
for at least 14 days before being discarded as negative.
• Identification: Biochemical & Serological (growth
inhibition test, agar gel precipitation test, ELISA, FAT, HI,
Agglutination test).

17. • Routine monitoring of flocks for MG and MS infection is usually
by the RSA, (Rapid Sera Agglutination also known as the Plate
test, SPA) or ELISA test. Testing is usually recommended to be
every 3 weeks in high risk areas
• Yolk samples from eggs can be tested in ELISA format tests and
may be useful, especially if access to the parent flock is not
possible or is a problem from a biosecurity point of view
Monitoring by serology

18. Serum separation for ELISA
Collection of choanal swab

19. • In the field, many cases of M. gallisepticum infection are complicated by
other diseaseproducing bacteria. Therefore, effective treatment must also
attack the secondary invaders.
• Most strains of mycoplasma M. gallisepticum are sensitive to a number of
antibiotics, but are resistant to penicillins or other antibiotics which act by
inhibiting cell wall
• A combination of colistin and tylosin with other anti-bacterials generally
helps and effect will be better if bronchodilators are also used in drinking
water for 3-5
• tetracyclines, tylosin, tiamulin, quinolones (enrofloxacin) and tilmicosin
but most of these are bacteriostatic rather than bacteriosidal.
tetracyclines, tylosin, tiamulin, quinolones (enrofloxacin) and tilmicosin
but most of these are bacteriostatic rather than bacteriosidal.
Treatment

20. The avian respiratory system is
involved in the following
functions:
absorption of oxygen (O2)
release of carbon dioxide (CO2)
release of heat (temperature
regulation)
detoxification of certain chemicals
rapid adjustments of acid/base
balance

21. Use of vaccines:
(a) Killed vaccines:
(b) Live vaccines: These are of three types: F strain vaccine, 6/85
strain vaccine, and ts-11 vaccine
Management: Because M. gallisepticum can be transmitted by
egg, maintaining chicken flocks free of M. gallisepticum is
possible only by starting with breeding stocks that are free of the
infection.
Prevention and Control

22. biosecurity is extremely important in the control of disease
Suggestions and Comments
Biosecurity – Preventing disease in poultry

30. The use of anolyte in poultry
The addition of neutral anolyte into the drinking
water ...
improves feed conversion
promote immunity
increases the resistance to disease
permits an increase in the vitality
reduces mortality by 50 to 70%
allows a higher life weight at lower feed consumption
reduced the use of antibiotics
eliminates E-coli, salmonella, coccidiosis
improving the quality of the feed of the animals
Minimizes the impact of mortality during epidemics
reduced the amount of small eggs increases the
quality and the uniformity of the calibration of eggs