Isolation ofMycoplasma gallisepticumfrom geese

Mycoplasma species in the male reproductive organs and the fresh and frozen semen of the Hungarian native goose

The objective of this study was to clarify whether the most common species of Mycoplasma can be detected in the reproductive organs and the cloaca, as well as in the semen of asymptomatic native Hungarian male geese. As it is necessary for the semen of that breed to be preserved pathogen-free in an in vitro gene-conservation programme, the presence of and sources of infection, as well as prevention of the survival of pathogens following semen cryopreservation, are key issues. Ten asymptomatic, 2-year-old ganders were tested. For the detection of mycoplasmas, samples were taken from both fresh and frozen/thawed semen, cloaca, phallus lymph, testes and vas deferens; that is five samples from each of the 10 ganders. The semen was statically frozen using dimethyl-formamide as a cryoprotectant and stored in liquid nitrogen at -196°C. Species-specific PCR systems targeting M. anserisalpingitidis, M. anseris and M. cloacale were used for screening and identification. Results of this study have shown, for the first time, that (1) among the three Mycoplasma species examined, all were detectable in the indigenous Hungarian ganders, with no clinical signs; (2) the pathogens could be detected in the cloaca, in both fresh and cryopreserved semen samples, but remained undetected within the inner reproductive organs; and (3) as pathogens were able to survive the freezing/storing/thawing procedures, the possibility of vertical transmission of the pathogens during artificial inseminations does exist, which causes problems in the in vitro gene-conservation programmes for this breed.

Clinical expression, epidemiology and monitoring of Mycoplasma gallisepticum and Mycoplasma synoviae: an update

Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) are of clinical and economic importance for the global poultry industry. Many countries and integrations are involved in monitoring programs to control both mycoplasma species. This review provides an extensive historic overview of the last seven decades on the development of the knowledge regarding the factors that influence the clinical expression of the disease, the epidemiology and monitoring of both MG and MS. This includes the detection of new virulent strains, studies unravelling the transmission routes, survival characteristics and the role of other avian hosts. Also the role of molecular typing tests in unravelling epidemiology, and factors that complicate the interpretation of test results such as heterologous mycoplasma infections, use of heterologous oil-emulsion vaccines, use of antibiotic treatments, occurrence of MG and MS strains with low virulence, and last but not least the use of live and/or inactivated MG and MS vaccines are discussed.

Mycoplasma anserisalpingitidis sp. nov., isolated from European domestic geese (Anser anser domesticus) with reproductive pathology

In 1983, Mycoplasma sp. strain 1220 was isolated in Hungary from the phallus lymph of a gander with phallus inflammation. Between 1983 and 2017, Mycoplasma sp. 1220 was also identified and isolated from the respiratory tract, liver, ovary, testis, peritoneum and cloaca of diseased geese in several countries. Seventeen studied strains produced acid from glucose and fructose but did not hydrolyse arginine or urea, and all grew under aerobic, microaerophilic and anaerobic conditions at 35 to 37 ˚C in either SP4 or pleuropneumonia-like organism medium supplemented with glucose and serum. Colonies on agar showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. Molecular characterization included analysis of the following genetic loci: 16S rRNA, 23S rRNA, 16S-23S rRNA ITS, rpoB, rpoC, rpoD, uvrA, parC, topA, dnaE, fusA and pyk. The genome was sequenced for type strain 1220^T. The 16S rRNA gene sequences of studied strains of Mycoplasma sp. 1220 shared 99.02-99.19 % nucleotide similarity with M. anatis strains but demonstrated ≤95.00-96.70 % nucleotide similarity to the 16S rRNA genes of other species of the genus Mycoplasma. Phylogenetic, average nucleotide and amino acid identity analyses revealed that the novel species was most closely related to Mycoplasma anatis. Based on the genetic data, we propose a novel species of the genus Mycoplasma, for which the name Mycoplasma anserisalpingitidis sp. nov. is proposed with the type strain 1220^T (=ATCC BAA-2147^T=NCTC 13513^T=DSM 23982^T). The G+C content is 26.70 mol%, genome size is 959110 bp.

A Novel Mycoplasma sp. Associated with Phallus Disease in Goose Breeders: Pathological and Bacteriological Findings

In April 2014, poor fertility in a major commercial goose breeder operation in California triggered the submission of six live affected Toulouse ganders ( Anser anser ) to the California Animal Health and Food Safety Laboratory, Turlock branch (University of California-Davis). Toulouse were principally affected among all breeds, and their egg fertility dropped from 65.7% to less than 33.9% in the first 40 days of the 2014 breeding season. The flock consisted of 410 adult birds, 90 males and 320 females, between 2 and 5 yr of age. Inspection of the flock revealed that 44.4% of the Toulouse ganders had severe phallic deformities that prevented them from mating. At postmortem examination, severe yellowish fibrocaseous exudate disrupted the architecture of the phallus and occasionally produced fistulating tracts through the wall of the organ. Microscopically, multifocal lymphoid nodules were noted in the mucosa and submucosa of the phallus and were associated with extensive granulomatous reaction, intralesional bacteria, and spermatozoa. Mycoplasma spp. were isolated from the phallus of affected and nonaffected birds, and PCR protocols targeting the 16S-23S ribosomal RNA intergenic spacer regions and the RNA polymerase beta subunit gene were performed to identify the isolates. Three distinct species were identified on sequencing and analysis using the National Center for Biotechnology Information basic local alignment search tool: Mycoplasma cloacale , Mycoplasma anseris , and an unknown novel Mycoplasma sp. Additionally, Pasteurella multocida , in combination with other bacteria, was also isolated from the phallic lesions and identified as serotype 3 with a DNA profile of 1511 (National Veterinary Service Laboratory). This is the first report of these Mycoplasma spp. and other bacteria associated with reproductive disease in ganders in the United States.

Pathogenicity of Mycoplasma imitans in mixed infection with infectious bronchitis virus in chickens

Mycoplasma imitans (Mim) has been isolated from ducks, geese and partridges, and is closely related to Mycoplasma gallisepticum (Mg). The pathogenicity of Mim for chicks was investigated in single and mixed infections with infectious bronchitis virus (IBV) by giving IBV strain M41 at 1-day-old and Mim 2 days later. Single infections with IBV or Mim were also performed. No clinical signs or gross lesions were seen in chicks infected with Mim or uninfected control chicks, but they were seen in the other two groups. Clinical scores were consistently higher in birds with mixed infections than those infected with IBV alone, and were significantly higher (P < 0.05) between days 7 and 14. More birds developed sinusitis, tracheitis and airsacculitis (with greater severity) in the mixed than the single IBV infections. Mim was recovered more frequently and in greater numbers from the respiratory tract of birds with mixed than single infections. It was recovered from the lower trachea, air sacs and lungs only in mixed infections. Seroconversion to Mim occurred by day 14 in mixed infections, but not until day 21 in single infections. It appears that Mim can act synergistically with IBV in young chickens in a similar manner to Mg, although Mg may act as a primary pathogen under some circumstances.

Identification and functional characterization of Toll-like receptor 2-1 in geese

Background

Toll-like receptor 2 (TLR2), an important pattern recognition receptor, activates proinflammatory pathways in response to various pathogens. It has been reported in humans and chicken, but not in geese, an important waterfowl species in China. Since some vaccines stimulate robust immune responsesl in chicken but not in geeeses we speculated that their immune systems are different.

Results

In this study, we cloned the goose TLR2-1 gene using rapid amplification of cDNA ends (RACE)and showed that geese TLR2-1 encoded a 793-amino-acid protein, containing a signal secretion peptide, an extracellular leucine-rich repeat domain, a transmembrane domain and a Toll/interleukin-1 receptor signaling domain deduced from amino acid sequence. TLR2-1 shared 38.4%–93.5% homology with its homologues in other species. Tissue expression of geese TLR2-1 varied markedly, and was higher in kidney, cloacal bursa, skin and brain compared to other organs/tissues. HEK293 cells transfected with plasmids carrying goose TLR2-1 and NF-κB-luciferase responded significantly to stimulation with Mycoplasma fermentans lipopeptide. Furthermore, geese infected with Mycoplasma gallisepticum (MG) and Salmonella enteritidis (SE) showed significant upregulation of TLR2-1 in both in vivo and in vitro.

Conclusion

Geese TLR2-1 is a functional homologue of TLR2 present in other species and plays an important role in bacterial recognition in geese.

Mycoplasma infection of ducks and geese

Production of ducks and geese in certain parts of the world is very important. Mycoplasma diseases cause significant losses to the duck and goose industry. This review summarizes the epidemiological, clinical, and pathomorphological characteristics of mycoplasma diseases of ducks and geese and the involvement of the various mycoplasma species in their pathogenesis. The role of mycoplasma infections in the development of clinical signs, pathological lesions, and mortality of challenged birds is demonstrated in challenge experiments. Transmission of mycoplasma in the ovary and eggs resulting in the reduction of egg production and an increase of embryo mortality has been shown in challenge experiments as well as in field studies. The susceptibility of many mycoplasma isolates of the most important mycoplasma species of duck and goose origin were tested and showed relatively high average minimum inhibitory concentrations of lincomycin, tilosin, oxytetracycline, chlortetracycline, and enrofloxacin but not for tiamulin. The successful treatment of mycoplasma infections with antibiotics in ducks and geese should be selected based on the minimum inhibitory concentration values against the mycoplasmas isolated from the flock.

Salpingitis in geese associated with Mycoplasma sp. strain 1220

An outbreak of disease in a White Rhine laying goose flock was characterized by increased water uptake, increased mortality, production of eggs with abnormal shells, a 25% drop in egg production and 40% embryo mortality. Affected dead or sacrificed birds had sero-fibrinogranulocytic peritonitis and salpingitis, infiltration of the lamina propria in the uterus and heterophil granulocytes in the isthmus and magnum of the oviduct. Mycoplasmas, mainly identified as Mycoplasma sp. strain 1220, were isolated from the airsac, liver, ovary, magnum and peritoneum of some affected geese. Strain 1220 was originally isolated from a Hungarian gander with phallus inflammation and, according to detailed biochemical and serological examinations, it is expected to represent a new avian species within the genus Mycoplasma.

Real-time polymerase chain reaction for the qualitative and quantitative detection ofMycoplasma gallisepticum

The aim of this study was to evaluate the sensitivity and the detection limit of a real-time polymerase chain reaction (Q-PCR) developed for the qualitative and quantitative detection of Mycoplasma gallisepticum. No cross-reactivity was observed with DNA from other important avian mycoplasmas, including Mycoplasma synoviae and Mycoplasma meleagridis. However, the Q-PCR could not distinguish between M. gallisepticum and Mycoplasma imitans. The Q-PCR had detection limits 10 to 1000 times lower than a conventional commercial PCR method and than culture. The Q-PCR was used quantitatively by incorporating a set of external M. gallisepticum DNA standards, derived from a M. gallisepticum log-phase culture of a known concentration. The number of colony-forming unit equivalents per millilitre in tracheal swabs from experimentally infected birds could be determined from a single sample. The method had good reproducibility and correlated well with standard counting techniques using culture. It can be concluded that the Q-PCR described is suitable for qualitative and quantitative detection of M. gallisepticum in clinical samples.

A putative transposase gene in the 16S–23S rRNA intergenic spacer region of Mycoplasma imitans

Examination of the nucleotide sequences of the 16S–23S intergenic transcribed spacer (ITS) region ofMycoplasma imitansandMycoplasma gallisepticumidentified a putative transposase gene located only in the ITS ofM. imitans, which can be used as a genetic marker to distinguish these two species. The relative size of the PCR products of the ITS region allowed a clear distinction to be made between strains ofM. imitansandM. gallisepticum, both of which could be readily discriminated from the type strains of all the other recognized avianMycoplasmaspecies. In addition, the putative transposase gene assigned in the ITS ofM. imitanswas shown to include a sequence homologous to that of the P75 gene ofM. gallisepticum. This is believed to be the first description of an insertion element in the rRNA operon region of a mycoplasma species.

Isolation of mycoplasmas from clinically healthy adult breeding geese in Germany

Cloacal swabs from adult breeding geese of both sexes from six separate farms were culturally examined for mycoplasmas. Geese from these flocks did not show any clinical signs of illness, increased mortality or drop in egg production during the reproductive season. The results revealed the presence of mycoplasmas in all the flocks tested. Mycoplasma (M.) cloacale was found in 6 flocks, M. anseris in 4 flocks, Mycoplasma species 1220 in 3 flocks and non-identifiable Mycoplasmas in 2 flocks. More than one Mycoplasma species was simultaneously isolated from 14 out of 37 geese.