Isolation and Characterization of Mycoplasma mycoides Subspecies capri from Milk of Natural Goat Mastitis Cases

The role of Mycoplasma ovipneumoniae and Mycoplasma arginini in the respiratory mycoplasmosis of sheep and goats in Italy: Correlation of molecular data with histopathological features

Mycoplasma infections are commonly found in the respiratory system of small ruminants; the species most commonly detected are Mycoplasma ovipneumoniae and Mycoplasma arginini, associated with the so-called "atypical non-progressive pneumonia". The pathogenic role of M. ovipneumoniae in pneumonia has been demonstrated in sheep but still needs to be verified in goats; on the other hand, the role of M. arginini in sheep is not well understood, while in goats seems to be of low pathogenic value. The present study aims to investigate the aetiology of pneumonia in sheep and goats that died from respiratory disease using anatomopathological, histopathological, and molecular investigations and to clarify the role of respiratory mycoplasmas by the association of molecular data with histopathological features. First, to better understand which histological changes are actually suggestive of atypical pneumonia in sheep and goats, the study identified the histological lesions significantly associated with Mycoplasma spp. infection. Then, the histological score of lesions considered suggestive of atypical pneumonia was used to estimate the pathogenicity of each mycoplasma detected. The results showed that M. ovipneumoniae and M. arginini (alone or in mixed infections) are pathogenic both in sheep, as well as in goats with similar histology and severity of lesions. Moreover, young animals were statistically more susceptible to M.ovipneumoniae and M. arginini infection than adults. Animals appeared more at risk to the development of M. ovipneumoniae and M. arginini infection in summer.

The prevalence and species of Mycoplasma identified from dairy goats in Taiwan

Except for Mycoplasma capricolum subsp. capripneumoniae, which only causes pneumonia, Mycoplasma species can cause otitis, arthritis, septicemia, mastitis, pneumonia and encephalitis in goats. After a mycoplasma outbreak was recorded in Taiwan in 2016, an increasing number of mycoplasma infection cases have been observed. It is important to understand how many Mycoplasma species are currently prevalent in Taiwan. In this study, 57-61 bulk milk samples were collected from dairy goats in Taiwan every year from 2017 to 2020 to identify the presence of mycoplasma DNA fragments by polymerase chain reaction (PCR). The mycoplasma species were identified based on colony characteristics, PCR, and DNA sequences. In total, 39 out of 236 samples (16.52%) tested mycoplasma positive. The annual mycoplasma prevalence rates from 2017 to 2020 were 24.59% (15/61), 8.20% (5/61), 17.54% (10/57) and 15.79% (9/57), respectively. Mycoplasma mycoides subsp. capri (n = 19), Mycoplasma putrefaciens (n = 10), Mycoplasma ovipneumoniae (n = 5) and Mycoplasma bovis (n = 5) were present in Taiwan. No M. capricolum subsp. capripneumoniae was detected. Except for the large drop in 2018, the prevalence of mycoplasma infection declined to a consistent level for the final two years of the study. However, the seasonal pattern is still worth investigating. This is the first survey of mycoplasma infection in goats, and we believe that a larger survey is still needed to understand the pathogenicity and diversity of these mycoplasma isolates.

Antimicrobial susceptibility profiles of Mycoplasma mycoides subsp. capri field isolates from goats in India

Erythromycin and Tylosin (Macrolides) followed by Tetracycline and Doxycycline (Tetracyclines) are found to be the best drugs of choice, under in-vitro antibiotic sensitivity test conducted with Disc diffusion method for the 10 Indian Mmc isolates recovered from goats. These relevant antibiotics may be recommended for use under field conditions. Although we have to keep in mind the gene exchange in Mollicutes along with other mechanisms, which may lead to the variation in their sensitivity to antibiotics in coming time.

Multilocus sequence typing of pathogenic Mycoplasma mycoides subsp. capri reveals the predominance of a novel clonal complex among isolates from goats in India

Mycoplasma mycoides subsp. capri (Mmc) typically causes pneumonia, mastitis, arthritis, keratitis and septicaemia in goats. Mortality associated with Mmc in goat flocks is lower compared to Mycoplasma capricolum subsp. capripneumoniae-associated respiratory infections. Case fatality rates associated with Mmc ranged from 9.8 to 26.8% among several states in India. Molecular epidemiology approaches aimed at genotyping help to identify the diversity of isolates involved in a disease. Ten clinical pathogenic Mmc isolates were analysed by multilocus sequence typing (MLST) for studying genotypic relationships with 50 isolates available from public databases. The MLST analysis indicates high genetic diversity among Mmc isolates. From a total number of 60 isolates, 43 six sequence types (STs) were recognized comprising of six STs from India and 37 STs from other geographical regions. MLST profiles of isolates revealed none of the STs observed in Indian isolates were shared with global isolates. Some of the STs representing Indian isolates (four STs) were clustered into a novel clonal complex 1 (CC1). Maintenance of genetically related STs forming CCs among the goat population in India for longer periods indicates disease causing potentiality of these isolates. Based on various recombination analysis, weak clonal relationship among Mmc isolates were identified. The present study has enlightened further steps in disease investigations and to design future control measures by employing prevalent genotypes as vaccine candidates against Mmc infections.

Isolation and molecular characterization of Mycoplasma spp. in sheep and goats in Egypt

Background and Aim:

Different species of Mycoplasma are associated with many pathological problems in small ruminants including respiratory manifestation, this problem results in significant losses, especially in African countries. This study aimed to (I) study some epidemiological aspects of Mycoplasma species infections in Egyptian sheep and goats at Giza Governorate, (II) diagnosis of Mycoplasma species affections using bacterial isolation and identification, (III) apply the polymerase chain reaction (PCR) for typing of different Mycoplasma species, and (IV) illustrate the phylogenetic tree for the isolated Mycoplasma species and other species from GenBank using the purified PCR product.

Materials and Methods:

A total of 335 samples were collected from sheep and goats from Giza Governorate in Egypt as 142 nasal swabs from clinically affected animals, 167 pneumonic lungs, 18 samples from tracheal bifurcation, and 8 samples by bronchial wash were cultured on pleuropneumonia-like organisms (PPLOs) media for cultivation of Mycoplasma species. PCR and sequencing and phylogenetic analysis were adopted to identify and classify the isolated Mycoplasma species.

Results:

A total of 24 Mycoplasma isolates were isolated on PPLO media, identified by biochemical tests, and confirmed and typed by PCR using specific primers. 10 isolates were confirmed as Mycoplasma arginini, four isolates as Mycoplasma ovipneumoniae by PCR, and 10 isolates as undifferentiated Mycoplasma species. A purified isolate of M. arginini and M. ovipneumoniae was sequenced and phylogenetic analysis was illustrated.

Conclusion:

M. arginini and M. ovipneumoniae are prevalent in Egyptian sheep and goats. Further studies on M. arginini are required due to its high frequency of isolation from pneumonic sheep and goats and also from animals suffer from different respiratory manifestations.

Prevalence and pathogens of subclinical mastitis in dairy goats in China

Subclinical mastitis, a costly disease for the dairy industry, is usually caused by intramammary bacterial infection. The aim of this study was to investigate the prevalence of and pathogens involved in subclinical mastitis in dairy goats in China. A total of 683 dairy goats in the main breeding areas of China were selected, and milk samples were collected. Out of these, 313 (45.82 %) goats were detected distinct or strong positive for subclinical mastitis by using California mastitis test. Among these positive goats, 209 milk samples were used to identify the causing agents by a multiplex PCR assay, and results were listed as follows: coagulase-negative staphylococci (59.52 %), Staphylococcus aureus (15.24 %), Escherichia coli (11.43 %), and Streptococcus spp. (10.95 %). In conclusion, subclinical mastitis is a highly prevalent disease in dairy goats in China, and coagulase-negative staphylococci are the predominant pathogens.