tailieunhanh - Mycoplasmoses in poultry

Within the 2001–7 period, the poultry industry reached its peak in 2003; meat yield was 372 700 metric tonnes and egg production was 4 852 million eggs. Poultry live weight per capita per year was kg (equivalent to kg carcass weight per person). The number of eggs per capita is 60 eggs, or kg of eggs per person (Statistical Yearbook of Viet Nam, 2004), which is lower than in China ( kg), Thailand ( kg), Malaysia and the United States of America ( kg) (author’s calculations). In December 2003, poultry industries in Viet Nam became strongly. | Rev. sci. tech. Off. int. Epiz. 1996 15 4 1495-1525 Mycoplasmoses in poultry L. STIPKOVITS and I. KEMPF Summary The most important mycoplasmas isolated from domestic avian species include Mycoplasma gallisepticum MG M. synoviae MS M. meleagridis MM and M. iowae MI . MG causes chronic respiratory disease of chickens and infectious sinusitis in turkeys resulting in economic losses. MS causes infectious synovitis or mild upper respiratory disease. MM infects only turkeys causing airsacculitis and sub-optimal production and hatchability. Ml is associated with reduced hatchability in turkey flocks. Transmission is either direct from bird to bird or through the egg or indirect. Diagnosis is based on isolation and identification of mycoplasmas according to biochemical serological or molecular biology tests or serological examination of host sera by slide agglutination haemagglutination inhibition or enzyme-linked immunosorbent assay ELISA tests. Antibiotics . tetracyclines macrolides quinolones and tiamulin may be used for therapeutic treatment or prophylactic medication. The eradication of mycoplasma infection can be achieved through improvements in hygiene and management practices therapeutic treatment of breeder layers and or of hatching eggs and better monitoring procedures. KEYWORDS Avian mycoplasmas - Diagnosis - Mycoplasma gallisepticum - Mycoplasma iowae - Mycoplasma meleagridis -Mycoplasma synoviae - Poultry - Symptoms. INTRODUCTION Micro-organisms of the class Mollicutes also called mycoplasmas and in earlier texts pleuropneumoniae-like organisms or PPLO contain both deoxyribonucleic acid DNA and ribonucleic acid RNA lack a cell wall carry the smallest prokaryotic genome down to 5 X 108 kilodaltons kDa and have fewer than 300 genes. Mollicutes are divided into two orders Mycoplasmatales with two families Mycoplasmataceae containing two genera Mycoplasma and Ureaplasma and Spiroplasmataceae containing one genus Spiroplasma and Acholeplasmatales with one family