ABSTRACT
Mycoplasma capricolum subsp. capripneumoniae (Mccp) is the cause of contagious caprine pleuropneumonia (CCPP) in goats. Inactivated vaccines and capsular polysaccharide (CPS) indirect hemagglutination reagents are available for prevention and serological detection, but high culture costs and complex antigen quantification have been plagued by production staff. In order to solve these problems in production practice, a sugar fermentation medium with an initial pH value of 7.8, which could improve the production of two antigens simultaneously, was screened out by changing the initial pH value based on previous Mccp metabolomics analysis. Since phenol red can be identified by UV absorption spectrum and cetyltrimethylammonium bromide (CTAB) can bind to anionic capsular polysaccharide, a UV spectrum measurement method for analyzing the culture stage reached by Mccp and a CTAB precipitation test for relative quantification of capsular polysaccharide antigen content in the fermentation broth were established. The UV spectrum observation method can guide the production of Mccp according to the growth curve of Mccp, which greatly reduces the monitoring time of the traditional CCU method and improves the accuracy of the original eye-observation method. The established CTAB precipitation test can complete the monitoring of CPS content within 5 hours, which greatly reduces the time required compared with the traditional differential technique, and its accuracy was verified by the phenol-sulfuric acid method. The optimized culture medium and the two correlation comparison methods established in this study can effectively reduce the production cost of Mccp and improve the production efficiency. The two assays have been used in the research at our laboratory, which provides experimental data for further improvement of the production process of CCPP inactivated vaccine and capsular polysaccharide as well as rapid quantification.
Subject(s)
Humans , Animals , Goats , Cetrimonium , Mycoplasma , PolysaccharidesABSTRACT
Abstract Objective: The aim of the study was detection of two major causative agents of pleuropneumonia, Mycoplasma capricolum subsp. capripneumoniae (Mccp) and Mannheimia haemolytica, in goats. To the best of our knowledge, this study is the first investigation of Mccp in Iran. Methods: 50 grossly suspected lungs to pleuropneumonia and 10 healthy samples were collected from Shiraz abattoir. Results: Histopathological evaluation of tissue samples showed various diagnosed pneumonias including 40% bronchointerstitial pneumonia (20 samples), 34% interstitial pneumonia (17 samples), 10% fibrinopurulent bronchopneumonia (5 samples), 12% purulent bronchopneumonia (6 samples) and 4% chronic pneumonia (2 samples). In molecular study, all 50 suspected samples and 10 healthy ones by PCR showed no Mccp positive sample, but the detection rate of M. haemolytica in suspected samples was 14% and in healthy lungs was zero. Conclusions: It may be concluded that goats referred to Shiraz abattoir is free of Mccp. Further sampling and molecular testing at the level of suspected herds to CCPP can be useful.
Resumen Objetivo: El objetivo del estudio fue la detección de dos agentes causantes principales de pleuroneumonía, Mycoplasma capricolum subsp. Capripneumoniae (Mccp) y Mannheimia haemolytica, en cabras. Hasta donde sabemos, este estudio es la primera investigación de Mccp en Irán. Métodos: 50 pulmones muy sospechosos de pleuroneumonía y 10 muestras sanas se obtuvieron del matadero de Shiraz. Resultados: La evaluación histopatológica de muestras de tejido mostró varias neumonías diagnosticadas, incluyendo 40% de neumonía broncointersticial (20 muestras), 34% de neumonía intersticial (17 muestras), 10% de bronconeumonía fibrinopurulenta (5 muestras), 12% de bronconeumonía purulenta (6 muestras) y 4% neumonía crónica (2 muestras). En un estudio molecular, las 50 muestras sospechosas y 10 sanas por PCR no mostraron una muestra positiva de Mccp, pero la tasa de detección de M. haemolytica en muestras sospechosas fue del 14% y en pulmones sanos fue cero. Conclusiones: se puede concluir que las cabras referidas al matadero Shiraz están libres de Mccp. La realización de muestreo adicional y pruebas moleculares a nivel de rebaños sospechosos para CCPP puede ser útil.