Mycoplasmosis in Poultry PDF

Mycoplasmosis in Poultry By: Magdy Elkady Professor of poultry diseases Dean of Faculty of Veterinary Medicine Beni-suef University  CHRONIC RESPIRATORY DISEASE (CRD) It is a term of respiratory affection in poultry in which airsacuilitis ,perihepati...

Mycoplasmosis in Poultry By: Magdy Elkady Professor of poultry diseases Dean of Faculty of Veterinary Medicine Beni-suef University  CHRONIC RESPIRATORY DISEASE (CRD) It is a term of respiratory affection in poultry in which airsacuilitis ,perihepatitis and peritonitis are the predominant lesions Mycoplasma gallisepticum (MG) is the primary cause of CRD as it open the gate for other bacterial complication specially E.COLI leading to previous mentioned lesions. Also, CRD may be it self complication after respiratory viral infection (AI,ND,IB) or bad managemental conditions at this case called CCRD (complicated CRD) Magdy Elkady TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY. DISEASE CONDITION. CL. SIGNS AND P.M. ECONOMIC LOSSES. PREVENTION AND CONTROL. CONCLUSIONS Magdy Elkady TOPICS INTRODUCTION. Magdy Elkady  Avian Mycoplasmosis Mycolasmosis is considered one of the most costliest problems confronting the poultry industry all over the world. Usually complicated by other respiratory infections, (E. coli, viruses) M. gallisepticum infections are also known as: 1. Chronic respiratory disease (CRD) of chickens. 2. Infectious sinusitis of turkeys. Magdy Elkady TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. Magdy Elkady  Etiology  Mycoplasma: the smallest free-living organisms (bacteria-like)  Class mollicutes  Order mycoplasmatales  Family mycoplasmataceae including: 1. M. gallisepticum 2. M. Synoviae 3. M. meleagridis 4. M. iowae. Citti & Blanchard, 2013. Trend Microbiol. 21(4):196–203 Magdy Elkady 7  Characteristics  Unlike other bacteria, Mycoplasma lacks a cell wall:  Plasticity  Able to pass through 0.2 micron filters  Pleomorphic (coccoidal and filamentous)  Poorly stained by bacterial stains  Antibiotic resistance, e.g., penicillins Magdy Elkady 8 TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS Magdy Elkady  Variant/Atypical strains of Mg and Ms  Atypical MG and MS strains resulting after treatments characterized by: Reported in both chickens and turkeys. Reduced virulence rarely show obvious clinical disease Spread slowly; low transmissibility (mainly egg transmission) Antigenically different from known standard strains Difficult to isolate Irregularly detected serologically (SPA, HI and ELISA). Confirmed by the in-vivo bioassay technique in SPF chickens Magdy Elkady (need 4-6 weeks). 10 TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY Magdy Elkady Pathogenesis Magdy Elkady 12  Epidemiology: Species Affected  So far, at least 25 species have been reported in birds  The 4 most important spp. are MG, MS, MM, and MI Exp: experimental infection only ?? : questionable Magdy Elkady 13 Epidemiology: Transmission Magdy Elkady 14 Epidemiology: Survival  Can reproduce and survive only within a host or under certain culture conditions  Susceptible to heat and drying, and to most disinfectants But… survival outside the host is longer than originally Magdy Elkady believed 15 Epidemiology: Incubation Period  Experimentally infected poultry develop symptoms after 6 -21 days.  In natural infections, the incubation period is variable; infected birds may be asymptomatic for days or months until stressed e.g,: Viral infections Vaccination with live viruses Cold weather Crowding These can trigger disease outbreaks in infected flocks. Magdy Elkady 16 TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY. DISEASE CONDITION. Magdy Elkady  Mycoplasma Disease Conditions  Mycolasmosis induce variable disease conditions including: M.Gallisepticum (Mg) M. Synoviae (Ms) M. meleagridis M. iowae (Mi) (Mm) - CRD in chickens - Arthritic form - Airsacculitis in - Moderate - IS in turkeys (Infectious synovitis) young poults airsacculitis - Keratoconjunctivitis - Respiratory form - Poor growth, - Leg and joint /Chickens and game - Subclinical infection feathering abnormalities: birds (airsacculitis) in - Skeletal - Chondrodystrophy - Salpingitis/chickens boilers deformities and - Reduced - Egg production - Atrophy of bursa and Perosis hatchability in losses thymus - Ascites Turkeys - Bursal atrophy Magdy Elkady 18  Mycoplasmosis prevalence Breeders East Europe: West Europe: MG:15-30% MG 0-10% MS:15-50% MS: 0-70% Asia MG: 0-80% MS: 5-50% Latin America: MG: 15-30% MS: 25-60% Mid-East & Africa: MG: 30-40% Survey of Elanco's TC, 1998 MS: 20-60% Magdy Elkady TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY. DISEASE CONDITION. CL. SIGNS AND P.M. Magdy Elkady Clinical Signs  Infected chickens usually develop respiratory symptoms that may include: 1. Depression. 2. Rales. 3. Coughing. 4. Sneezing. 5. Nasal discharges. 6. Dyspnea. 7. Decreased weight gain, feed efficiency 8. Decreased egg production. Magdy Elkady 21 Clinical Signs Conjunctivitis Sinusitis Depression Drop in egg Conjunctivitis22 production Corneal opacity Magdy Elkady Clinical Signs Magdy Elkady PM Lesions Eyelid, Infraorbital sinus, nares Trachea exudates Air sac Lungs Magdy Elkady PM Lesions Heart Keel, Pectoral muscles Image sources Cornell University College of Veterinary Medicine http://www.vet.cornell.edu/news/poultry.cfm Magdy Elkady TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY. DISEASE CONDITION. CL.SIGNS AND P.M. ECONOMIC LOSSES. Magdy Elkady Economic Losses  Mycoplasmosis is the most economically significant pathogen of poultry causing significant economic losses on poultry farms from: 1. Direct Losses: Chronic respiratory disease (CRD). Reduced feed efficiency. Decreased growth rate 10-25 % Carcasses downgrades 5-10% Decreased egg production 8-20% 2. Indirect Losses: Immunosuppression Disease condition aggravation Magdy Elkady Elkady MF. Avian Mycoplasmosis 27  Direct economic losses MG in U.S. Commercial Layers Infected Farms: – Multi-age : 75% – Single age: 15% Losses in US $ Total No. of layers in U.S. 174, 900, 000 mil. Percentage infected 37% No. 20 eggs Average egg loss per hen Money (0.05$/egg) $1.00 · Total annual losses $97,160,000 Magdy Elkady Elkady MF. Avian Mycoplasmosis 28  Mycoplasma effect on hatchability Breeder/layer Production effect Egg drop (acute) 10-20% Egg drop (chronic effect) 5-10% Embryo mortality increase / hatchability drop 5-10% Often there is impaired hatchability, due to late term embryo death, in eggs from infected flocks. Embryo mortality is highest after eggs are transferred to the hatcher and at pipping.  Mycoplasma Iowae (Turkey embryo) Magdy Elkady  In Egypt….. MG in Egyptian Commercial Layers Losses in LE Total number of layers 20 000 000 layer Percentage of infections 85% No. 15 eggs Average egg loss/hen Money (0.35 LE/egg) 5.25 Total annual losses 89 250 000 LE  Drop in egg production is associated with:  Downgraded eggs: Increased egg shell damage: 8% cracked eggs vs. 2% from non-infected flocks.  Increased embryo and chick mortality (5-10%). Magdy Elkady Elkady MF. Avian Mycoplasmosis 31  Mycoplasma Indirect Losses Immunosuppression Destroying receptors on macrophages Decreased phagocytosis Destroying receptors on lymphoblasts and lymphocytes Preventing differentiation to Th,Tc and plasma cells Magdy Elkady 32 Mycoplasma Indirect economic Losses Aggravation of disease conditions  Mycolasmosis Increased sensitivity to Other pathogens  Enhance lesions and increase mortality when co-infected with E.coli 40 35 30 25 20 15 10 5 0 MG+E.coli E.coli MG Control Air sac Lesions Mortality Magdy Elkady 33 Mycoplasma Indirect Losses (Co-infection) Aggravation of disease conditions  Mycolasmosis Increased sensitivity to Other pathogens  increase egg production losses when co-infected with E.coli 70 MG E.Coli 60 50 Egg Production % 40 30 % 20 10 0 0 10 20 30 40 50 60 70 80 90 100 110 120 Negative Control MG Inf. MG+E.coli inf. Magdy Elkady 34 Co-Infection Mycoplasmosis and IBV The multiplication of M. gallisepticum was greatly enhanced in the tracheas of chickens which had been previously or simultaneously infected with avian infectious bronchitis virus (Chu and Uppal 1975). M. gallisepticum was found in all farms infected with IBV (Sid et al., 2015). Magdy Elkady  Experimental co-infection Magdy Elkady (S.Umar etal,..2017) 36 TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY. DISEASE CONDITION. CL.SIGNS AND P.M. ECONOMIC LOSSES. PREVENTION AND CONTROL Magdy Elkady  Prevention and Control Prevention Mainly in Breeder Biosecurity flocks Vaccination Control Mainly in broiler Treatment flocks Magdy Elkady Prevention: Vaccination  Vaccination is the preferred method of control to maintain MG- and MS-free flocks.  Vaccination should be considered only in situations where: 1. Field exposure is inevitable (e.g. multi-age systems. 2. Potential exposure of neighboring poultry. Magdy Elkady Elkady MF. Avian Mycoplasmosis 39  Live vaccines  The objective is to infect the flock with a mild, immunogenic MG strain at an age and time when little or no significant damage occurs. Vaccine Criteria Dosage Age of Route strain vaccination The F avirulent strain for Single dose : Drinking water, strain chickens virulent for 10 log 5 Spray, Eye drop. turkeys. CFU/dose Respiratory reaction Spreads slowly and 12-16 weeks of 5 -7 days after spary laterally spread by 4 age. vaccination wks after vaccination If early field exposure Strains ts- ≥ 10 log 7.7 Eye drop. expected at 2-4 11 avirulent strains but (CCU)/dose No post-vaccination weeks of age. spread from vaccinated reaction 6/85 strain to unvaccinated birds 10 log 7–8 Fine spray. does not occur or occurs CFU/dose No post-vaccination very poorly reaction Magdy Elkady Elkady MF. Avian Mycoplasmosis 40 Effects of Mycoplasma live vaccines F strain is unsuitable for use in turkeys because it is too virulent Respiratory signs and air sacculitis may occur after aerosol vaccination or in the presence IBV, NDV Egg production was significantly less (by 5.76% and 5.80% in two trials) after F-strain vaccination but no obvious effect on oviduct structure and function Egg quality parameters were unaffected. Magdy Elkady Elkady MF. Avian Mycoplasmosis 41 Inactivated vaccines  Bacterins provide protection against egg-production drops that occur after MG exposure on multi-age layer sites.  Reduce the level of egg transmission in breeder pullets.  Vaccination with one or two doses of bacterin: Delayed the onset and Reduced the rate of transmission of M. gallisepticum through the egg Field observations: continued use of bacterin on multiple- age farms had failed to eliminate the infection. Magdy Elkady Elkady MF. Avian Mycoplasmosis 42 Treatment  The (semi) permanent use of antibiotics (Tylan®, Lincospectin®, Baytril®) can reduce the damage of a M.G. infection, but it will never really solve the problem, because the flocks are still infected.  In broilers, at the first 4 days of life, then at 19th day for 2 successive days.  In breeders, following any respiratory vaccination, especially ND for 2 successive days. As soon medication stops the disease increases again Magdy Elkady Elkady MF. Avian Mycoplasmosis 43 Limitations of Treatment 1. Mycoplasma develops resistance against the antibiotics 2. Expensive 3. Medication can not fully prevent an infection. 4. This system can be useful for a relatively short period of time, but in the meantime other control systems have to be developed. Magdy Elkady Elkady MF. Avian Mycoplasmosis 44 Egg transmission Treatment  MG positive flock depopulation. The only completely safe procedure to prevent further spread (Not always practical)  Treatment of the hatching egg 0.2 mg tylosine tylan® (or baytril®) Manual or automatic Injection Egg dipping in a 2500 ppm containing tylan solution, using the temperature-difference method or the pressure difference method. Magdy Elkady Elkady MF. Avian Mycoplasmosis 45  General Control strategy No one control strategy fits every country and all bird species. Magdy Elkady Control in an applied term 1 2 3 4 5 Diagnostics Control on Biosecurity & infected Depopulation Vaccination surveillance birds Magdy Elkady Everybody must follow all rules NO EXCEPTIONS! Magdy Elkady  Biosecurity Measures Sanitation and Traffic control Magdy Elkady Developing your biosecurity own program Magdy Elkady  Breaking the cycle Infection Susceptible Site host contamination Transmission Vaccination, Biosecurity Medication, Management Magdy Elkady  Surveillance Molecular diagnosis. – PCR Conventional diagnosis. – Isolation of the virus. – Antigen detection. Magdy Elkady  Dead birds disposal Magdy Elkady Magdy Elkady TOPICS INTRODUCTION. ETIOLOGY AND CHARACTERISTIC. STRAINS. PATHOGENESIS AND EPIDEMIOLOGY. DISEASE CONDITION. CL.SIGNS AND P.M. ECONOMIC LOSSES. PREVENTION AND CONTROL CONCLUSIONS Magdy Elkady  Conclusions Mycolasmosis is a significant disease problems facing the poultry industry all over the world Delicate organism does not mean easy control Mycoplasma is capable to cause immunesuppression Medication only will never really solve the mycoplasmosis problem Strict hygienic system is an essential mean of control Use both live and killed vaccine (depending only on bacterin do not eliminate the infection. Un supervised use of live mycoplasma vaccines can trigger disease outbreaks esp. in presence of other respiratory diseases Magdy Elkady Thank you for attention Magdy Elkady