Studies on mycoplasma infection of laying 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.

Multilocus sequence typing of the goose pathogen Mycoplasma anserisalpingitidis

Mycoplasma anserisalpingitidis infection is associated with the inflammation of the genital tract and cloaca, embryo lethality, and decreased egg production in geese, leading to serious economic losses. M. anserisalpingitidis has been detected mainly in Central and Eastern Europe, especially in Hungary, but the pathogen was identified recently in China, predicting it's worldwide occurrence. In this study, a novel multilocus sequence typing (MLST) scheme was developed to analyse phylogenetic relationships between M. anserisalpingitidis field isolates and clinical specimens originating from different geographical locations. Five loci (atpG, fusA, pgiB, plsY, and uvrA) were selected for the final MLST study. The examined 89 M. anserisalpingitidis samples yielded 76 unique sequence types with a 0.994 Simpson's index of diversity. The samples were originated from Hungary, Poland, Ukraine, China, and Vietnam. Phylogenetic analysis revealed the existence of three distinct clades (A-C) and six subclades within clade C. Generally, samples originating from the same geographical locations or livestock integration clustered together. Isolates in clade A showed the closest relationships to the M. anatis outgroup due to sequence similarity of the plsY locus. The highest genetic distance was observed in 5C among the subclades of clade C, containing the Asian and some Hungarian field isolates. The developed MLST assay revealed high diversity of the investigated M. anserisalpingitidis samples. The method proved to be a valuable and cost-effective tool for sequence typing of this waterfowl Mycoplasma species, enabling the better understanding of its phylogeny and providing a robust assay for future molecular epidemiological investigations.

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.

Detection of Mycoplasma anatis, M. anseris, M. cloacale and Mycoplasma sp. 1220 in waterfowl using species-specific PCR assays

Mycoplasma anatis, M. anseris, M. cloacale and M. sp. 1220 colonise geese and ducks, and could be associated with infections of avian respiratory and nervous systems, cause mild to severe inflammation of cloaca and genital tracts, and embryo lethality. Co-occurrence of these Mycoplasma species in waterfowl is frequently detected and the identification of these mycoplasmas to the species level at a regular microbiology laboratory is difficult due to their similar morphological, cultural and biochemical properties. Moreover, species differentiation is only possible based on the sequence analysis of the product of a genus-specific PCR assay. Therefore, the aim of the current study was to develop an effective and robust method for the identification of these species in avian clinical specimens. Polymerase chain reaction (PCR) assays using species-specific primers, which target housekeeping genes in order to identify these species, were designed in the present study. The developed PCR assays can precisely identify these four mycoplasmas to the species level directly from DNA samples extracted from clinical specimens, and no cross-amplification was observed among these species and with other well-known avian mycoplasmas. The average sensitivity of the assays was 10¹−10² genomic equivalents per reaction. These conventional PCR assays can be run simultaneously at the same PCR cycling program, and the species can be differentiated directly (without sequence analysis) by gel electrophoresis due to the specific sizes of the amplicons. In conclusion, the presented species-specific assays were found to be suitable for routine use at regular veterinary diagnostic laboratories and promote the rapid, simple and cost-effective differentiation of these waterfowl Mycoplasma species.

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.

Trichodinosis associated with pathology of the reproductive tract in waterfowl

Trichodinid ciliophorans are opportunistic parasites of many species of fish, amphibians, and molluscs, but yet never reported in association with lesions in birds. Postmortem and histopathological evaluation of a commercial adult Toulouse gander and female goose, and a wild Mallard drake revealed the presence of severe pathological parasitic colonization of their reproductive tracts. Histopathological findings included moderate to severe granulocytic inflammation, acanthosis, accentuation of the rete pegs, and proliferative hyperplastic squamous metaplasia of the mucosa of the ejaculatory ducts and groove, sulcus spermaticus, glandular part of the phallus (cavum penis), and oviduct in association with large numbers of ciliated protozoa anchored to the tissues or free in the lumen. These protozoa had characteristic morphological features analogous to the family of Trichodinidae. The source of this parasitism could not be determined. To our knowledge, this is the first report of trichodinosis associated with pathology in birds.

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.

Pathological and immunological studies on goose embryos and one-day-old goslings experimentally infected with a Mycoplasma strain of goose origin

Goose embryos and one-day-old goslings were inoculated either on the 10th or 20th day of incubation into the yolk sac or into the air sac or intranasally, with Mycoplasma strain 1220 isolated from a goose. Subsequently morphological, immunological and microbiological * changes were determined. Infection during incubation resulted in an acute serous inflammation of the chorioallantoic membrane, a diffuse, heterophil granulocytic interstitial hepatitis and a bronchopneumonia. One-day-old goslings developed lympho-histiocytic infiltrations of the productive type in the interstitium of the lungs, the walls of the major bronchi, the mucous membrane of the nasal conchae and in the visceral pleura. Blood lymphocytes of 28-day-old embryos infected at 10 days of incubation recognised and specifically reacted with the antigen in immunorosette formation and lymphocyte transformation tests. However, after hatching the antigen-recognising capacity of lymphocytes decreased, and had become considerably reduced by day 30 after hatching. No antibodies were demonstrable in the indirect haemagglutination test.

Occurrence of mycoplasmas in geese affected with inflammation of the cloaca and phallus

The spread of inflammation of the cloaca and phallus in goose flocks was investigated. In the flocks surveyed, 57.5 to 71.8% of the initial gander stock and 39.8 to 100% of the replacement ganders were affected. Based on the results of several hundred attempts at mycoplasma isolation, a relationship was found between mycoplasma infection and the occurrence of inflammation of the cloaca and phallus in the flocks. Mycoplasmas were frequently isolated from the mucous membrane of the phallus, the pallic lymph, and the inner organs of ganders in the affected flocks, but not from birds in unaffected flocks. Two biochemically (glucose-splitting and arginine-hydrolysing) and three serologically distinct types of mycoplasmas have been isolated. One of them proved to be identical to strain 46, identified by J.M. Bradbury as M. cloacale, and two strains may represent new Mycoplasma species since they differ serologically from all previously known Mycoplasma spp. In the diseased flocks, the strain designated 1220 (8390) and the antibodies produced against it were of most frequent occurrence. At the peak of egg production, mycoplasmas were isolated from 92.1% of the phallic lymph samples, and 94.6% of the test sera were positive for antibodies to strain 1220 (8390).

Additional data on Mycoplasma disease of goslings

Epidemiological, pathomorphological, histological and microbiological studies on 272 gosling from 51 flocks showed that disease occurred generally at 3 to 4 weeks of age with morbidity of 15 to 25% and mortality of 3 to 8%. It was characterized by respiratory and nervous symptoms accompanied by serous-fibrinous inflammation of the mucosal membrane of the respiratory tract, pericardium and cerebral membranes. Mycoplasmas of 1220 type were isolated from trachea and airsac walls of 50% of the samples tested, but no adeno or reoviruses could be detected in homogenates of trachea and airsac wall, and no serological response indicative of Derzsy's disease could be demonstrated. E. coli, Ps. aeruginosa, S. typhimurium and Sir. pyogenes were occasionally cultured from the heart and liver of goslings. Cloacal and oviduct swabs and phallus lympha samples from five parent goose flocks also frequently revealed 1220 type mycoplasmas.

Phallus-inflammation of ganders: clinical observations and comparative bacteriological examinations of healthy and altered organs

The examination of acute or chronically altered phallus-tissues of ganders revealed microorganisms belonging to the genera Mycoplasma, Bacteroides, Clostridium, Streptococcus, Micrococcus, Staphylococcus, Lactobacillus, Corynebacterium, Escherichia, Campylobacter, Proteus, Pseudomonas and Candida and to the family Pasteurellaceae, isolated in different frequencies. Bacteriologic examinations of the phallus-tissues and cloacal mucous membranes of healthy juvenile ganders showed microorganisms of the same genera or family, except Mycoplasma and Candida spp. Pathogenesis and possibilities of treating phallus-inflammations in ganders are discussed.