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Florence Tardy - One of the best experts on this subject based on the ideXlab platform.

  • Contagious Agalactia in sheep and goats current perspectives
    Veterinary Medicine : Research and Reports, 2019
    Co-Authors: Florence Tardy
    Abstract:

    : Contagious Agalactia (CA) is a disease caused equally by four Mycoplasma species, in single or mixed infections. Clinical signs are multiple, including mastitis, arthritis, keratoconjunctivitis, pneumonia, and septicemia, non-specific, and expressed differently depending whether sheep or goats are affected, on causative mycoplasmas as well as type of husbandry. CA has been reported worldwide and its geographic distribution maps to that of small ruminant breeding areas. However, as current diagnostic tests are expensive and difficult to implement, it is certainly underdiagnosed and prevalence data are only available for a few countries. CA control relies on vaccines, chemotherapy and good herd management practices. It requires long-term commitment but is often unsuccessful, with frequent clinical relapses. The persistence of the etiological agents, despite their overall susceptibility to antimicrobials, comes from their genetic plasticity and capacity to escape the host immune response. The existence of asymptomatic carriers and the numerous sources of infections contribute to rapid spread of the disease and complicate the control and prevention efforts. Here we review all these aspects in order to highlight recent progress made and identify gaps in knowledge or tools needed for better disease management. Discussion also underlines the detrimental effect of Contagious Agalactia on small ruminant welfare.

  • Contagious Agalactia monitoring in caprine herds through regular bulk tank milk sampling
    Journal of Dairy Science, 2019
    Co-Authors: Florence Tardy, M Treilles, Chloe Ambroset, A Tricot, C Maingourd, J Vialard, Le D Grand
    Abstract:

    ABSTRACT Surveillance and control of Mycoplasma spp. responsible for Contagious Agalactia (CA) in caprine herds are important challenges in countries with a large small-ruminant dairy industry. In the absence of any clinical signs, being able to determine the potential circulation of mycoplasmas within a herd could help to prevent biosecurity issues during animal exchanges between farms and improve health management practices. The objective of this study was to determine whether regular sampling of bulk tank milk was suitable for such surveillance. Twenty farms were sampled once a month for 2 yr and CA-responsible mycoplasmas were detected by real-time PCR on DNA extracted from milk, using 3 different DNA extraction methods. The pattern of mycoplasma excretion in bulk tank milk was assessed over time and several herd characteristics were recorded together with any event occurring within the herds. In general, the results obtained with the different detection methods were comparable and mainly agreed with the culture results. Several patterns of excretion were observed but were not related to herd characteristics (size, breed, and so on). Recurrence of the same (sub)species and same pulsed-field gel electrophoresis subtype during the 2-yr period is indicative of the considerable persistence of mycoplasmas. This persistence was associated with intermittent excretion. In conclusion, bulk tank milk sampling could be valuable for controlling CA in caprine herds provided it is repeated several times, yet to be defined, per year and analyzed using an appropriate methodology and the right cut-off for interpretation.

  • the moderate drift towards less tetracycline susceptible isolates of Contagious Agalactia causative agents might result from different molecular mechanisms
    Veterinary Microbiology, 2018
    Co-Authors: Juan Tataydualde, C Ambroset, Florence Tardy
    Abstract:

    Abstract Contagious Agalactia is a mycoplasmosis that affects small ruminants, is associated with loss of milk production and high morbidity rates, and is highly deleterious to dairy industries. The etiological agents are four mycoplasma (sub)species, of which the relative importance depends on the countries and the animal host. Tetracyclines are non-expensive, broad-spectrum antimicrobials and are often used to control mastitis in dairy herds. However, the in vitro efficiency of tetracyclines against each of the etiological agents of Contagious Agalactia has been poorly assessed. The aims of this study were i) to compare the tetracycline susceptibilities of various field isolates, belonging to different mycoplasma (sub)species and subtypes, collected over the years from different clinical contexts in France or Spain, and ii) to investigate the molecular mechanisms behind the decreased susceptibility of some isolates to tetracyclines. The Minimum Inhibitory Concentrations (MICs) of tetracyclines were determined in vitro on a set of 120 isolates. Statistical analyses were run to define the significance of any observed differences in MICs distribution. As mutations in the genes encoding the tetracycline targets (rrs loci) are most often associated with increased tetracycline MICs in animal mycoplasmas, these genes were sequenced. The loss of susceptibility to tetracyclines after year 2010 is not significant and recent MICs are higher in M. Agalactiae, especially isolates from mastitis cases, than in other etiological agents of Contagious Agalactia. The observed increases in MICs were not always associated with mutations in the rrs alleles which suggests the existence of other resistance mechanisms yet to be deciphered.

  • Unexpected genetic diversity of Mycoplasma Agalactiae caprine isolates from an endemic geographically restricted area of Spain.
    BMC Veterinary Research, 2012
    Co-Authors: J Amores, Florence Tardy, Eveline Sagné, Laurent-xavier Nouvel, Christine Citti
    Abstract:

    Background The genetic diversity of Mycoplasma Agalactiae (MA) isolates collected in Spain from goats in an area with Contagious Agalactia (CA) was assessed using a set of validated and new molecular typing methods. Validated methods included pulsed field gel electrophoresis (PFGE), variable number of tandem repeats (VNTR) typing, and Southern blot hybridization using a set of MA DNA probes, including those for typing the vpma genes repertoire. New approaches were based on PCR and targeted genomic regions that diverged between strains as defined by in silico genomic comparisons of sequenced MA genomes.

  • development of a multiplex real time pcr for Contagious Agalactia diagnosis in small ruminants
    Journal of Microbiological Methods, 2012
    Co-Authors: Claire A M Becker, Francois Poumarat, Fabien Ramos, Eric Sellal, Sandrine Moine, Florence Tardy
    Abstract:

    Contagious Agalactia is an important disease worldwide that affects small ruminants. Clinical manifestations vary from mastitis, pneumonia, arthritis and keratoconjunctivitis to septicemia. Four mycoplasmal etiological agents have been identified: Mycoplasma (M.) Agalactiae, M. mycoides subsp. capri, M. capricolum subsp. capricolum and M. putrefaciens. The current procedure for direct diagnosis, recommended by the World Organization for Animal Health, involves the isolation of one or several causative agents from clinical specimens and further time-consuming identification steps. The present study reports the development of a new multiplex real-time PCR (including an internal positive control) that detects all four pathogens simultaneously and distinguishes M. Agalactiae from the others. First, intra- and inter-species polymorphisms of the two target house-keeping genes, namely polC and fusA, were analyzed to design primers and probes adapted to the diversity of currently circulating strains. The specificity and the sensitivity of the assay were then challenged and the limit of detection was found to be as low as 6 to 12 copies of the target genes. The assay requires further assessment on clinical specimens but its performances (notably low intra- and inter-assay variability) are already very promising for use in large-scale diagnosis and prophylactic surveys of Contagious Agalactia.

Robin A J Nicholas - One of the best experts on this subject based on the ideXlab platform.

  • validation of loop mediated isothermal amplification lamp field tool for rapid and sensitive diagnosis of Contagious Agalactia in small ruminants
    Open Access Journal, 2020
    Co-Authors: Serena Tumino, Robin A J Nicholas, Roberto Puleio, Marco Tolone, Alessio Parco, Giuseppe Arcoleo, C Manno, G R Loria
    Abstract:

    Contagious Agalactia (CA), an infectious disease of small ruminants, caused by Mycoplasma Agalactiae, is responsible for severe losses to dairy sheep production with substantial socioeconomic impacts on small-scale farmers. The diagnosis of CA is still problematic, time-consuming and requires well-equipped labs for confirmation of outbreaks. Therefore, rapid, accurate and cost-effective diagnostic tests are urgently needed. This work aims to validate a novel Loop-Mediated Isothermal Amplification (LAMP) test, based on the p40 target gene, for the detection of M. Agalactiae in dairy sheep in order to confirm its potential practical use as a rapid and cheap field test. The LAMP system proposed in this study consists of a portable device composed of real-time fluorometer with the automatic interpretation of results displayed in a tablet. A total of 110 milk samples (90 positives and 20 negatives) were analysed to optimise the analysis procedure and to investigate the efficacy and robustness of the LAMP method. All samples were analysed using LAMP and conventional real-time PCR to compare the diagnostic sensitivity of the methods. The sensitivity of the LAMP was 10-fold higher than that of real-time PCR, with a detection limit up to 103 CFU/ml. The LAMP assay was able to detect M. Agalactiae in 81 of 90 (90%, 95%CI 0.84–0.96) positive milk samples compared to 69 (77%, 95%CI 0.59–0.95) positive samples detected by real-time PCR; no positive signal occurred for any of the negative milk samples in either test. Therefore, the LAMP assay was found to be more sensitive than real-time PCR, low-cost, easy to perform, fast and not affected by contamination, indicating its potential as an effective diagnostic tool in the field level for the diagnosis of CA.

  • Effect of Mycoplasma Agalactiae mastitis on milk production and composition in Valle dell Belice dairy sheep
    Italian Journal of Animal Science, 2019
    Co-Authors: Marco Tolone, Robin A J Nicholas, Roberto Puleio, Serena Tumino, Anna Maria Sutera, Silvio Borrello, Maria Luisa Scatassa, Baldassare Portolano, Guido Ruggero Loria
    Abstract:

    Contagious Agalactia (CA), a disease caused by Mycoplasma Agalactiae and other pathogenic mycoplasmas, is a well-known multietiological syndrome affecting dairy breeds of sheep and goats in...

  • can vaccines for Contagious Agalactia reduce disease progression in infected animals a preliminary study
    Veterinary Record Case Reports, 2018
    Co-Authors: G R Loria, Roberto Puleio, Stefano Agnello, Gavino Marogna, Robin A J Nicholas
    Abstract:

    A flock of sheep in Central Sicily was affected by a severe outbreak of Contagious Agalactia (CA) caused by Mycoplasma Agalactiae, affecting nearly 30% resulting in a large drop in milk production. Many ewes had warm and swollen udders that often became sclerotic and was accompanied by keratoconjunctivitis and arthritis in both adults and young. As antibiotic treatment appeared ineffective, the whole flock was given two doses of an inactivated vaccine against M Agalactiae two weeks apart. A small group was selected for close examination and additional tests. A fortnight after the last vaccination mycoplasma excretion fell in all but one of the selected ewes and was undetectable in all but two animals two weeks after that. In nearly all the selected ewes, there was an improvement in milk quality and udder condition. This work provided preliminary evidence for the continued use of CA vaccines to slow or prevent disease progression.

  • Severe otitis and pneumonia in adult cattle with mixed infection of Mycoplasma bovis and Mycoplasma Agalactiae
    Veterinary Record Case Reports, 2016
    Co-Authors: Salvatore Catania, Federica Gobbo, Eliana Schiavon, Robin A J Nicholas
    Abstract:

    Respiratory disease and otitis were seen on a northern Italian farm in weaned bulls obtained from multiple sources. Mycoplasma bovis was consistently identified in nasal swabs, tonsil, ears, eyes and lung samples from affected animals. Unusually the closely related Mycoplasma Agalactiae , the main cause of Contagious Agalactia (CA) in small ruminants, was also isolated. It was identified by molecular methods in bulls but only from eye, ear and brain samples. Outbreaks were reduced by retaining the bulls on their original farms for weaning, then moving them directly to the fattening areas on the farm. This prevented the spread of mycoplasma from infected to uninfected calves from different sources. As no small ruminants were within close proximity and the area is free of CA, it is possible that M Agalactiae may be more prevalent in cattle than previously thought.

  • a comparison of the efficacy of commercial and experimental vaccines for Contagious Agalactia in sheep
    Small Ruminant Research, 2013
    Co-Authors: Annalisa Agnone, Robin A J Nicholas, Marco Pio La Manna, Guido Sireci, Roberto Puleio, Antonella Usticano, Umit Ozdemir, Valeria Chiaracane, Francesco Dieli, Vincenzo Di Marco
    Abstract:

    Abstract An effective vaccine that improves the control of Contagious Agalactia in Mediterranean regions would be beneficial for poorer farmers who use traditional husbandry methods for sheep and goat production. However while there is little published data on the efficacy of commercially available vaccines for Contagious Agalactia, evidence from the field suggests that some provide inadequate protection. This paper compares four different vaccine formulations, including a widely used commercial vaccine, using clinical signs and mycoplasma excretion as measures of protection in sheep. Results showed that protection afforded by the vaccines, following contact challenge with experimentally infected ewes, varied considerably. A live attenuated vaccine, presently forbidden in the European Union, conferred the best clinical protection, despite a lack of serological response, followed by a vaccine prepared by inactivating the mycoplasmas with saponin. A commercial vaccine inactivated with formalin provided no protection against this disease.

Roger D Ayling - One of the best experts on this subject based on the ideXlab platform.

  • species of mycoplasma causing Contagious Agalactia in small ruminants in northwest iran
    Veterinaria Italiana, 2018
    Co-Authors: Afshin Hajizadeh, Rainak Ghaderi, Roger D Ayling
    Abstract:

    Contagious Agalactia (CA) is a serious disease of small ruminants that occurs in many countries, and is usually characterized by mastitis, arthritis, keratoconjunctivitis, pleuropneumonia, and septicemia. Mycoplasma Agalactiae (Ma) is the main causative agent in sheep and goats but other pathogens including Mycoplasma mycoides subsp. capri (Mmc, which incorporates the former M. mycoides subsp. mycoides Large Colony type), Mycoplasma capricolum subsp. capricolum (Mcc), and Mycoplasma putrefaciens (Mp) might be involved. They are all usually associated with infections in goats and may cause similar clinical signs. A total of 116 sheep and 16 goats suffering from the acute form of the disease were included in this study. They were recruited following a number of outbreaks suspected to be CA in the Ardebil province of Iran. Milk, lachrymal or synovial fluid were collected exclusively from the affected animals in order to identify the pathogen involved. Of the 132 collected samples, 33 (25%) were positive for Mycoplasma species by culture in PPLO broth and agar. The polymerase chain reaction followed by denaturing gradient gel electrophoresis (PCR/DGGE) method identified 18 (12 sheep and 6 goats) of the 33 Mycoplasma positive samples with mixed Mycoplasma population. In particular, 25 Ma (47.2%), 23 Mp (43.4%), 4 Mcc (7.5%), and 1 Mmc (1.9%) were identified. This confirms that the several Mycoplasma species rather than the Ma only are in circulation, and are able to cause CA in sheep and goats in Iran. This is the first report on the isolation and identification of Mp, Mmc and Mcc in infected small ruminant flocks in Iran.

  • immunoproteomic characterisation of mycoplasma mycoides subspecies capri by mass spectrometry analysis of two dimensional electrophoresis spots and western blot
    Journal of Pharmacy and Pharmacology, 2015
    Co-Authors: Colin P Churchward, R S Rosales, R A J Nicholas, Adriana Gielbert, Mercedes Dominguez, Roger D Ayling
    Abstract:

    Objectives Mycoplasma mycoides subspecies capri is one of the causative agents of Contagious Agalactia in goats. The disease is characterised by mastitis, pneumonia, arthritis, keratitis and in acute cases septicaemia. No vaccine is currently available that has been demonstrated to prevent disease. Methods This study used two-dimensional electrophoresis to separate proteins from whole-cell preparations and tandem mass spectrometry to identify them. Key findings In total, 145 spots were successfully identified corresponding to 74 protein identities. Twenty of these proteins were found to be immunogenic by western blot analysis using a pooled serum sample from experimentally infected goats. Conclusions Six proteins were found to have a less than 95% amino acid similarity to a closely related Mycoplasma species showing that they warrant further evaluation in development of diagnostic tests. These proteins were a dihydrolipoamide acetyltransferase component of the pyruvate dehydrogenase complex, phosphoglycerate kinase, pyrimidine-nucleoside phosphorylase, 30S ribosomal protein S6, ribulose-phosphate 3-epimerase and D-lactate dehydrogenase.

  • vntr analysis reveals unexpected genetic diversity within mycoplasma Agalactiae the main causative agent of Contagious Agalactia
    BMC Microbiology, 2008
    Co-Authors: Laura Mcauliffe, G R Loria, Colin P Churchward, J R Lawes, Roger D Ayling, Robin A J Nicholas
    Abstract:

    Background Mycoplasma Agalactiae is the main cause of Contagious Agalactia, a serious disease of sheep and goats, which has major clinical and economic impacts. Previous studies of M. Agalactiae have shown it to be unusually homogeneous and there are currently no available epidemiological techniques which enable a high degree of strain differentiation.

  • VNTR analysis reveals unexpected genetic diversity within Mycoplasma Agalactiae, the main causative agent of Contagious Agalactia
    BMC Microbiology, 2008
    Co-Authors: Laura Mcauliffe, Colin P Churchward, J R Lawes, Roger D Ayling, Guido Loria, Robin A J Nicholas
    Abstract:

    Background Mycoplasma Agalactiae is the main cause of Contagious Agalactia, a serious disease of sheep and goats, which has major clinical and economic impacts. Previous studies of M. Agalactiae have shown it to be unusually homogeneous and there are currently no available epidemiological techniques which enable a high degree of strain differentiation. Results We have developed variable number tandem repeat (VNTR) analysis using the sequenced genome of the M. Agalactiae type strain PG2. The PG2 genome was found to be replete with tandem repeat sequences and 4 were chosen for further analysis. VNTR 5 was located within the hypothetical protein MAG6170 a predicted lipoprotein. VNTR 14 was intergenic between the hypothetical protein MAG3350 and the hypothetical protein MAG3340. VNTR 17 was intergenic between the hypothetical protein MAG4060 and the hypothetical protein MAG4070 and VNTR 19 spanned the 5' end of the pseudogene for a lipoprotein MAG4310 and the 3' end of the hypothetical lipoprotein MAG4320. We have investigated the genetic diversity of 88 M. Agalactiae isolates of wide geographic origin using VNTR analysis and compared it with pulsed field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD) analysis. Simpson's index of diversity was calculated to be 0.324 for PFGE and 0.574 for VNTR analysis. VNTR analysis revealed unexpected diversity within M. Agalactiae with 9 different VNTR types discovered. Some correlation was found between geographical origin and the VNTR type of the isolates. Conclusion VNTR analysis represents a useful, rapid first-line test for use in molecular epidemiological analysis of M. Agalactiae for outbreak tracing and control.

  • Ovine mycoplasmal infections
    Small Ruminant Research, 2008
    Co-Authors: Robin A J Nicholas, Roger D Ayling, Guido Ruggero Loria
    Abstract:

    Abstract Compared to other ruminants like cattle and goats, sheep are not as prone to the same range or severity of mycoplasmal infections. The main mycoplasmal diseases of sheep are Contagious Agalactia (CA), caused by Mycoplasma Agalactiae, atypical pneumonia, caused by M. ovipneumoniae and infectious keratoconjunctivitis (“pink-eye”), caused by M. conjunctivae: all are important diseases, but rarely life-threatening in their own right. However, recent isolations of mycoplasmas from mixed flocks of sheep and goats in the Middle East require a reassessment of the ovine mycoplasmal flora. There have been sporadic isolations of many other mycoplasmas, including the human organism, M. fermentans, but their link to disease has not been proven. This review paper summarises ovine mycoplasmas and the diseases that they cause or are associated with.

Patricia Assunção - One of the best experts on this subject based on the ideXlab platform.

  • mechanisms involved in quinolone resistance in mycoplasma mycoides subsp capri
    Veterinary Journal, 2015
    Co-Authors: Nuno T Antunes, Patricia Assunção, José B. Poveda, Maria M Tavio
    Abstract:

    Abstract Mycoplasma mycoides subsp. capri is a causative agent of Contagious Agalactia in goats. In this study, M. mycoides subsp. capri mutants were selected for resistance to fluoroquinolones (norfloxacin, enrofloxacin and ciprofloxacin) by serial passes in broth with increasing concentrations of antibiotic. Mutations conferring cross-resistance to the three fluoroquinolones were found in the quinolone resistance determining regions of the four genes encoding DNA gyrase and topoisomerase IV. Different mutations in the DNA gyrase GyrA subunit suggest a different mechanism of inhibition between norfloxacin and the other tested fluoroquinolones. The presence of an adenosine triphosphate-dependent efflux system was suggested through the use of the inhibitor orthovanadate.

  • Survey of antibodies to Mycoplasma Agalactiae and Mycoplasma mycoides subsp. mycoides (large colony type) in dromedaries (Camelus dromedarius) in close contact with an infected goat population
    Journal of Arid Environments, 2009
    Co-Authors: Patricia Assunção, Ana S Ramirez, F Fabelo, Carlos Poveda, Carlos Gutiérrez, José B. Poveda
    Abstract:

    Given recent evidence of a possible role of camelids in the epidemiology of diseases caused by mycoplasma species in other ruminants, we examined the prevalence of the mycoplasmas most commonly responsible for Contagious Agalactia (CA) in small ruminants among the dromedaries (Camelus dromedarius) of Lanzarote. On this island, one of the most arid regions of Spain in which CA is considered endemic, dromedaries and infected small ruminants such as goats and sheep, live in close contact. Specific IgG antibodies against Mycoplasma Agalactiae and Mycoplasma mycoides subsp. mycoides (large colony biotype) were determined using two indirect enzyme immunoassays in 28% of the island's dromedary population. None of the serum samples tested were found to have antibodies against the two mycoplasma species, suggesting that the camels are not potential carriers of the main causative agents of CA.

  • effects on goat milk quality of the presence of mycoplasma spp in herds without symptoms of Contagious Agalactia
    Journal of Dairy Research, 2009
    Co-Authors: Antonio Sanchez, Patricia Assunção, A Contreras, J C Corrales, Aldo Gutierrez, Carlos Poveda, José B. Poveda
    Abstract:

    This study was designed to assess the possible effects of mycoplasmas on the quality of milk produced by goat herds in a Contagious Agalactia (CA) endemic area with absence of classical symptoms. Several factors related to milk quality (percentages of fat, total protein, lactose and total solids, standard plate counts (SPC) and presence of Staphylococcus aureus) were compared in mycoplasma-infected and non-infected herds. To define the CA status of 26 herds on the island of Lanzarote (Spain), where CA is endemic, 570 individual milk samples and 266 bulk tank milk (BTM) samples were microbiologically analysed for the presence of Mycoplasma spp. A herd was considered infected by mycoplasmas when at least a sample (individual or BTM) was positive. BTM samples were also used to determine milk quality parameters. Mycoplasma infection was confirmed in 13 herds. A total of 31, 10 and 11 strains of Mycoplasma mycoides subsp. mycoides LC (MmmLC), Mp. Agalactiae and Mp. capricolum subsp. capricolum were isolated. No significant differences were observed between the least square means of the variables fat, total protein, lactose and total solids or SPC recorded for the infected v. noninfected herds. The Staph. aureus status of a herd was also found to be independent of the presence of Mycoplasma spp. Our findings indicate that neither the presence of mycoplasmas in a goat herd with absence of classical symptoms seem to compromise the quality of the BTM.

  • field trial of two dual vaccines against mycoplasma Agalactiae and mycoplasma mycoides subsp mycoides large colony type in goats
    Vaccine, 2007
    Co-Authors: Patricia Assunção, Sebastiana Tola, Carlos Poveda, P Saavedra, J B Poveda
    Abstract:

    Two vaccines against Mycoplasma Agalactiae and Mycoplasma mycoides subsp. mycoides (LC type) were developed using inactivated strains selected in previous characterization studies. The vaccines differed in terms of the adjuvants used: aluminium hydroxide (vaccine A) or aluminium hydroxide plus purified saponin (vaccine B). These vaccines were tested on 60 pregnant goats and 60 seronegative kids that were challenged by placing in a herd with a history of caprine Contagious Agalactia (CCA). Our findings indicate the effectiveness of the vaccines in preventing the appearance of new clinical signs such as mastitis, abortion, pneumonia and polyarthritis in CCA affected herds.

  • Contagious Agalactia in small ruminants
    Small Ruminant Research, 2007
    Co-Authors: J C Corrales, Patricia Assunção, José B. Poveda, A Sanchez, A Esnal, A Contreras
    Abstract:

    Contagious Agalactia (CA) is an infectious syndrome caused by several species of mycoplasma and classically characterized by the triad of mammary, joint and eye symptoms, although further symptoms may also appear. CA is the most serious disease of whatever they affect in small dairy ruminants and so there is an urgent need for administrative bodies and farmers to join forces and design serious strategies with the final aim of completely eradicating the disease. CA is endemic in the Mediterranean and certain Asian and African regions, while in America it is described as sporadic. The emergence of CA in a non-infected herd is almost always linked to the introduction of carriers of CA or to contact with infected herds. It normally implies the rapid spread of clinical problems in the herd coinciding with the period of parturitions and the start of lactation. In endemic areas, this disease provokes subclinical or mild clinical symptoms, and the lack of an established, systemized diagnostic procedure implies, that many infected herds pass unnoticed and may act as a permanent source of infection. Enzyme-linked immunosorbent assay (ELISA) techniques are recommended for the detection of antibodies, but the systematic vaccination of herds in endemic areas prevents the use of serology to detect infected herds. Then, culture and polymerase chain reaction (PCR) techniques must be used. In clinical outbreaks, control measures should be directed towards limiting the economic losses of the herd and avoiding the spread of the disease by isolating the infected herd, antibiotic treatment, selective culling, disinfection measures and the classic prevention measures for mastitis (correct functioning and maintenance of milking equipment, the milking routine, teat dipping, etc.). In chronically infected herds, control measures should be directed to restrict disease spread by way of prevention measures for mastitis, detection and culling of animals with lesions, the administration of antimycoplasma drugs to all animals at the end of lactation, adequate management of replacement animals and, perhaps, vaccination.

A Contreras - One of the best experts on this subject based on the ideXlab platform.

  • multilocus sequence typing of mycoplasma mycoides subsp capri to assess its genetic variability in a Contagious Agalactia endemic area
    Veterinary Microbiology, 2016
    Co-Authors: Juan Tataydualde, A Paterna, A Contreras, Angel Gomezmartin, J C Corrales, Antonio Sanchez
    Abstract:

    Abstract Mycoplasma mycoides subsp. capri (Mmc) is one of the main causative agents of caprine Contagious Agalactia. Besides, the absence of accurate control methods eases its dispersion between different herds within endemic areas of this disease. In this context, there is a need to implement molecular typing schemes which offer valuable information useful to establish control measures and enables the surveillance of this pathogen. The aim of this study was to assess the genetic variability of different strains of Mmc from a Contagious Agalactia endemic area through multilocus sequence typing (MLST). For this purpose, five house-keeping genes ( fusA , glpQ , gyrB, lepA, rpoB ) from 39 field isolates were analysed. These isolates were obtained from different geographic areas of Spain, between the years 2004 and 2015. The results obtained in this study suggest that the selected MLST scheme could be a useful technique to monitor the genetic variability of Mmc in endemic areas. Despite the significant differences found between the assessed field isolates, they could be classified according to their geographical origin. Moreover, it was also possible to detect genetic differences between Mmc strains coming from the same herd at the same sampling time, which may need to be taken into consideration when designing or arranging prophylactic strategies.

  • the diagnosis of mastitis and Contagious Agalactia in dairy goats
    Small Ruminant Research, 2014
    Co-Authors: A Paterna, A Contreras, Angel Gomezmartin, J Amores, Juan Tataydualde, J C Corrales, A Sanchez
    Abstract:

    Abstract This article reviews the diagnosis of mastitis in dairy goats. The benefits and shortcomings are discussed of both indirect diagnostic methods, such as the California mastitis test and somatic cell counts, and direct strategies, such as bacteriologic isolation and PCR identification. The important role of mycoplasmas in causing mastitis in regions where Contagious Agalactia is endemic makes their detection mandatory in routine diagnostic practice, despite complicating and lengthening protocols. In this context, we discuss both the conditions to be met prior to sampling and the analytical conditions of the sample along with the features of each diagnostic method.

  • controlling Contagious Agalactia in artificial insemination centers for goats and detection of mycoplasma mycoides subspecies capri in semen
    Theriogenology, 2012
    Co-Authors: Angel Gomezmartin, A Contreras, J Amores, J C Corrales, A Sanchez, A Paterna
    Abstract:

    Abstract Many goat artificial insemination (AI) centers in Spain have adopted new measures to control Contagious Agalactia (CA). To avoid the introduction of male goats carrying mycoplasma organisms subclinically in their external ear canal (auricular carriers) in these centers, two ear swabs and a blood sample are obtained from all candidate animals for polymerase chain reaction (PCR), culture (swabs) and serologic tests to detect the presence of mycoplasmas. In addition, the semen produced at these centers is routinely cultured and PCR tested also to detect the presence of mycoplasmas. One y after the introduction of this program, we tested 48 ear swabs and 24 blood samples from 24 candidates for admission to these AI Centers. Three of these ear swab samples (3/48, 6.25%) scored positive for the presence of mycoplasmas; Mycoplasma Agalactiae (Ma) was detected in two samples and Mycoplasma mycoides subsp. capri (Mmc) in one. All animals were serologically negative for Ma. Also, out of 173 semen samples obtained from 137 admitted animals (2 and 3 samples were obtained in 16 and 10 bucks, respectively), one (1/173, 0.56%) was positive for Mmc. Our findings suggest that ear swab and semen samples are useful tools to control CA at AI Centers. The introduction of this program has also resulted in the first detection of Mmc in semen from a naturally infected goat, confirming the ability of this mycoplasma to colonize the reproductive tract of male goats. These results highlight the need to improve control measures in semen producing centers to minimize the risk of CA transmission.

  • presence of Contagious Agalactia causing mycoplasmas in spanish goat artificial insemination centres
    Theriogenology, 2011
    Co-Authors: J Amores, Angel Gomezmartin, J C Corrales, A Sanchez, A Contreras
    Abstract:

    Abstract Male goats admitted to artificial insemination centres come from herds that have shown no clinical symptoms of Contagious Agalactia (CA) for the last 6 mo. However, prior reports suggest that this control measure may not be completely effective. This study was designed to detect the presence of CA-causing mycoplasmas in 9 Spanish centres, comprising 159 goats (147 males and 12 teaser does) of 8 different breeds. A microbiological study was conducted during 8 mo on 448 samples (318 ear swabs, 119 semen samples and 11 milk samples). In 86 samples (84 swabs, 1 semen sample and 1 milk sample), CA-causative mycoplasmas were detected by PCR or culture, and 52 animals (49 goat males and 3 teaser does) tested positive. Most of these positive animals were auricular carriers (n = 50), mainly of Mycoplasma mycoides subsp. capri (Mmc), although some M. Agalactiae (Ma) and, interestingly, M. capricolum subsp. capricolum (Mcc) carriers were also identified. At least 1 animal infected by CA-causing mycoplasmas was detected in 8 of the 9 centres (88.8%) although in most (66.7%) no infected animals or only 1 or 2 positive animals were identified. Our results indicate the presence of CA carriers as asymptomatic animals in reproductive programmes. These findings have already prompted efficient measures to detect and avoid the entry of these carriers in Spanish centres. We recommend similar measures for all centres in areas where CA is endemic.

  • effects on goat milk quality of the presence of mycoplasma spp in herds without symptoms of Contagious Agalactia
    Journal of Dairy Research, 2009
    Co-Authors: Antonio Sanchez, Patricia Assunção, A Contreras, J C Corrales, Aldo Gutierrez, Carlos Poveda, José B. Poveda
    Abstract:

    This study was designed to assess the possible effects of mycoplasmas on the quality of milk produced by goat herds in a Contagious Agalactia (CA) endemic area with absence of classical symptoms. Several factors related to milk quality (percentages of fat, total protein, lactose and total solids, standard plate counts (SPC) and presence of Staphylococcus aureus) were compared in mycoplasma-infected and non-infected herds. To define the CA status of 26 herds on the island of Lanzarote (Spain), where CA is endemic, 570 individual milk samples and 266 bulk tank milk (BTM) samples were microbiologically analysed for the presence of Mycoplasma spp. A herd was considered infected by mycoplasmas when at least a sample (individual or BTM) was positive. BTM samples were also used to determine milk quality parameters. Mycoplasma infection was confirmed in 13 herds. A total of 31, 10 and 11 strains of Mycoplasma mycoides subsp. mycoides LC (MmmLC), Mp. Agalactiae and Mp. capricolum subsp. capricolum were isolated. No significant differences were observed between the least square means of the variables fat, total protein, lactose and total solids or SPC recorded for the infected v. noninfected herds. The Staph. aureus status of a herd was also found to be independent of the presence of Mycoplasma spp. Our findings indicate that neither the presence of mycoplasmas in a goat herd with absence of classical symptoms seem to compromise the quality of the BTM.