Contagious agalactia: costs and control revisited.

The economic costs of contagious agalactia (CA) to the small ruminant dairy industry are not well known but include losses due to mortality, lowered milk production, spoiled products, abortions and animal welfare problems, as well as diagnosis and treatment. This paper reports financial estimates made in southern Europe, including a study on small- and large-scale farming systems in Italy, indicating that the financial losses are high and underestimated. Furthermore, the current control strategies, including chemotherapy and vaccination, in selected countries in Europe are described. In some countries, disease control is hampered by excessively strict veterinary legislation which discourages farmers and private veterinarians from notifying outbreaks because it leads to the prohibition of milk sales and can result in delays in lifting restrictions. In addition, new European Union legislation may downgrade the importance of CA, which will have implications for international research efforts. Finally, a series of recommendations are provided that cover the proper notification and handling of CA outbreaks, including movement control, current diagnostics, treatment, vaccination and disinfection.

Si le coût économique exact de l'agalaxie contagieuse pour le secteur ovin et caprin de production laitière n'est pas connu, on sait néanmoins qu'il recouvre les pertes dues à la mortalité dans les cheptels, à une chute de la production de lait, aux produits altérés, aux avortements et aux problèmes de bien-être animal, en plus des coûts du diagnostic et des traitements. Les auteurs font état d'estimations financières réalisées en Europe méridionale, dont une étude sur les exploitations familiales et les élevages de grande taille en Italie, qui coïncident dans le constat de pertes financières à la fois importantes et sous-estimées. Les auteurs décrivent également les stratégies de lutte mises en place actuellement par plusieurs pays d'Europe, en particulier l'antibiothérapie et la vaccination. Dans certains pays, les efforts de lutte sont entravés par une législation vétérinaire excessivement rigoureuse qui dissuade les éleveurs et les vétérinaires privés de notifier les foyers car cela entraîne l'interdiction de vendre le lait issu des troupeaux infectés et retarde la levée des mesures de restriction. En outre, la nouvelle réglementation de l'Union européenne risque d'abaisser l'importance de l'agalaxie contagieuse, ce qui aura des conséquences sur les efforts mobilisés par la recherche au niveau international. Pour conclure, les auteurs formulent plusieurs recommandations en vue d'une notification et gestion appropriées des foyers d'agalaxie contagieuse, notamment pour ce qui concerne le contrôle des mouvements d'animaux, les méthodes actuelles de diagnostic, le traitement, la vaccination et la désinfection.

Aunque no se conocen bien los costos económicos que la agalaxia contagiosa inflige a la industria lechera de pequeños rumiantes, se sabe que las pérdidas por mortalidad, mengua de la producción lechera, productos echados a perder, abortos y problemas de bienestar animal son un factor importante, sin olvidar los gastos de diagnóstico y tratamiento. Los autores dan cuenta de cálculos económicos realizados en Europa meridional, en particular a raíz de un estudio de pequeñas y grandes explotaciones ganaderas de Italia, que llevaron a la conclusión de que las pérdidas económicas son cuantiosas y están subestimadas. Además, los autores describen los métodos de lucha aplicados actualmente en determinados países de Europa, que incluyen tratamiento medicamentoso y vacunaciones. En algunos países la lucha contra la enfermedad se ve lastrada por una legislación veterinaria demasiado estricta, que no alienta a productores y veterinarios privados a notificar brotes porque ello conduce a la prohibición de las ventas de leche y puede demorar el levantamiento de las restricciones. Por otra parte, hay nuevos textos legislativos de la Unión Europea que quizá vengan a restar importancia a la agalaxia contagiosa, lo que repercutiría en las actividades internacionales de investigación. Por último, los autores formulan una serie de recomendaciones referidas a cuestiones que van desde la correcta notificación y gestión de los brotes de agalaxia contagiosa hasta el control de los desplazamientos, pasando por los procedimientos vigentes de diagnóstico o los métodos de tratamiento, vacunación y desinfección.

Search for OIE-listed ruminant mycoplasma diseases in Afghanistan.

BACKGROUND: Little is known about the occurrence of important diseases of ruminants in Afghanistan because of the conflict affecting the country over the last 40 years. To address this discrepancy, ruminant herds in Afghanistan were screened for OIE-listed mycoplasma diseases, contagious bovine (CBPP) and caprine pleuropneumonias (CCPP). RESULTS: Of the 825 samples from 24 provinces tested for serological evidence of CBPP caused by Mycoplasma mycoides subsp.mycoides, 20 (3.4%) had ELISA values greater than the positive threshold of 50% though all were less than 55%. Repeat testing of these suspect sera gave values below 50. A smaller number of sera (330) from cattle in nine provinces were also tested by the rapid latex agglutination test (LAT) for CBPP, 10 of which were considered suspect. However, no positive bands were seen when immunoblotting was carried out on all sera that gave suspect results. Serological evidence of Mycoplasma bovis was detected in half of 28 herds in eight provinces. The cause of CCPP, M. capricolum subsp. capripneumoniae was not detected in any of the 107 nasal swabs and lung tissue collected from goats in seven provinces though sample handling and storage were not optimal. However, strong serological evidence was detected in goat herds in several villages near Kabul some of which were over 50% seropositive by LAT and ELISAs for CCPP; immunoblotting confirmed positive results on a selection of these sera. CONCLUSIONS: The data presented here provide a first assessment of the occurrence of the two OIE listed mycoplasma diseases in Afghanistan. From the results of the testing bovine sera from the majority of provinces there is no evidence of the presence of CBPP in Afghanistan. However the samples tested represented only 0.03% of the cattle population so a larger survey is required to confirm these findings. Serological, but not bacterial, evidence was produced during this investigation to show that CCPP is highly likely to be present in parts of Afghanistan.

Comparison of different NAT assays for the detection of microorganisms belonging to the class Mollicutes.

BACKGROUND: Mollicutes detection can be cumbersome due to their slow growth in vitro. For this reason, the use of DNA based on generic molecular tests represents an alternative for rapid, sensitive and specific detection of these microorganism. For this reason, six previously described nucleic acid testing assays were compared to evaluate their ability to detect microorganisms belonging to the class Mollicutes. METHODS: A panel of 61 mollicutes, including representatives from the Mycoplasma, Acholeplasma, Mesoplasma, Spiroplasma and Ureaplasma genus, were selected to evaluate the sensitivity and specificity of these assays. A total of 21 non-mollicutes, including closely related non-mollicutes species, were used to evaluate specificity. Limits of detection were calculated to determine the analytical sensitivity of the assays. The two best performing assays were subsequently adapted into real-time PCR format, followed by melting curve analysis. RESULTS: Both assays performed satisfactorily, with a 100% specificity described for both assays. The detection limits were found to be between 10-4 and 10-5 dilutions, equivalent to 15 to 150 genome copies approximately. Based on our work, both van Kuppeveld and Botes real-time PCR assays were found to be the best performing tests in terms of sensitivity and specificity. Furthermore, Botes real-time PCR assay could detect phytoplasmas as well. CONCLUSIONS: These assays can be very useful for the rapid, specific and sensitive screening cell line contaminants, clinical samples as well as detecting non-culturable, unknown species of mollicutes or mollicutes whose growth is slow or difficult.

16S rRNA gene mutations associated with decreased susceptibility to tetracycline in Mycoplasma bovis.

Mycoplasma bovis isolates with decreased susceptibilities to tetracyclines are increasingly reported worldwide. The acquired molecular mechanisms associated with this phenomenon were investigated in 70 clinical isolates of M. bovis. Sequence analysis of the two 16S rRNA-encoding genes (rrs3 and rrs4 alleles) containing the primary binding pocket for tetracycline (Tet-1 site) was performed on isolates with tetracycline hydrochloride MICs of 0.125 to 16 µg/ml. Mutations at positions A965T, A967T/C (Escherichia coli numbering) of helix 31, U1199C of helix 34, and G1058A/C were identified. Decreased susceptibilities to tetracycline (MICs, ≥2 µg/ml) were associated with mutations present at two (A965 and A967) or three positions (A965, A967, and G1058) of the two rrs alleles. No tet(M), tet(O), or tet(L) determinants were found in the genome of any of the 70 M. bovis isolates. The data presented correlate (P<0.0001) the mutations identified in the Tet-1 site of clinical isolates of M. bovis with decreased susceptibility to tetracycline.

Global multilocus sequence typing analysis of Mycoplasma bovis isolates reveals two main population clusters.

Mycoplasma bovis is a major bovine pathogen associated with bovine respiratory disease complex and is responsible for substantial economic losses worldwide. M. bovis is also associated with other clinical presentations in cattle, including mastitis, otitis, arthritis, and reproductive disorders. To gain a better understanding of the genetic diversity of this pathogen, a multilocus sequence typing (MLST) scheme was developed and applied to the characterization of 137 M. bovis isolates from diverse geographical origins, obtained from healthy or clinically infected cattle. After in silico analysis, a final set of 7 housekeeping genes was selected (dnaA, metS, recA, tufA, atpA, rpoD, and tkt). MLST analysis demonstrated the presence of 35 different sequence types (STs) distributed in two main clonal complexes (CCs), defined at the double-locus variant level, namely, CC1, which included most of the British and German isolates, and CC2, which was a more heterogeneous and geographically distant group of isolates, including European, Asian, and Australian samples. Index of association analysis confirmed the clonal nature of the investigated M. bovis population, based on MLST data. This scheme has demonstrated high discriminatory power, with the analysis showing the presence of genetically distant and divergent clusters of isolates predominantly associated with geographical origins.

Isolation, molecular characterization and antimicrobial susceptibilities of isolates of Mycoplasma agalactiae from bulk tank milk in an endemic area of Spain.

AIM: To isolate and characterize strains of Mycoplasma agalactiae from bulk tank and silo ewes' milk. METHODS AND RESULTS: Thirteen mycoplasma isolates were obtained from samples of sheep milk taken from bulk tank and large silos and identified as Myc. agalactiae by PCR-DGGE. The isolates were typed by pulsed field gel electrophoresis (PFGE), SDS-PAGE and immunoblot. The in vitro activity of 13 antimicrobials of veterinary interest was tested against these isolates. Results showed that the most effective compounds against Myc. agalactiae in vitro were clindamycin, an antibiotic not previously described as a suitable contagious agalactia (CA) treatment, with Minimum Inhibitory Concentration (MIC) values of <0·12 µg ml(-1) , and quinolones, with MIC values <0·12-0·5 µg ml(-1) , which are used as standard treatments against CA. CONCLUSIONS: Based on the in vitro assay, clindamycin, quinolones, tylosin and tilmicosin would be appropriate antimicrobials for CA treatment. The isolates were mostly resistant to erythromycin, indicating that it would not be a suitable choice for therapy. The isolates showed common molecular and protein profiles by PFGE and SDS-PAGE, with minor differences observed by immunoblot analysis, suggesting a clonal relationship among them. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated the importance of the appropriate selection of antimicrobials for treatment of CA.

Mycoplasma neophronis sp. nov., isolated from the upper respiratory tract of Canarian Egyptian vultures (Neophron percnopterus majorensis).

Six strains with the typical characteristics of mycoplasmas were isolated from the tracheae of six Canarian Egyptian vultures (Neophron percnopterus majorensis). The results of biochemical, serological and molecular genetic studies showed that the isolates were nearly identical and that they could be considered as representing a novel species of the genus Mycoplasma. Colonies possessed the typical fried-egg appearance and electron micrographs revealed a pleomorphic cellular morphology with the lack of a cell wall. The isolates hydrolysed arginine and required sterol for growth but did not ferment glucose or hydrolyse urea. We propose that the isolates be assigned to a novel species,Mycoplasma neophronis sp. nov. The type strain is G.A.(T) ( = DSM 24097(T) = ATCC BAA-2157(T)). The antiserum of strain G.A.(T) has been deposited in the Mollicutes collection at Purdue University (Indiana, USA).

The relative responsiveness and construct validity of the Spanish version of the DASH instrument for outcomes assessment in open carpal tunnel release.

The objective of this study was to evaluate the responsiveness and construct validity of the Spanish version of the DASH as outcome measure for carpal tunnel surgery. The study population was 42 patients with the diagnosis of carpal tunnel syndrome (CTS) based on clinical and electrophysiological criteria. The clinical design was a classic Cohort study with measures the day before and 12 weeks after open carpal tunnel release. The Spanish version of the DASH was compared to the physical exam measures as dexterity time, grip and pinch strength, range of motion of the wrist (ROM) and two-point discrimination (2PPD). The responsiveness was evaluated based on the effect size (ES) and the standardised response means (SRM). The Spanish version of the CTS questionnaire (CTQ) and the Spanish version of the 36-item short-form health survey (SF-36) were self-administered to the same study population and followed the same clinical design. The hypothesis that the DASH instrument should present a responsiveness level higher than the SF-36 and lower than the CTQ was established to demonstrate the construct validity. The DASH instrument showed an ES of 0.68 and an SRM of 1.00. Responsiveness of traditional physical exam measures were lower, running from 0.35 (SRM) for dexterity time to 0.00 (ES) for key pinch strength. The SF-36 presented a responsiveness level (range from 0.07 to 0.14) lower that the DASH. The CTQ showed the highest level of responsiveness (ES = 1.41 and 0.7) (SRM = 1.75 and 0.51). In conclusion, The DASH instrument is more sensitive in detecting clinical change than the physical exam measures for use in clinical outcome studies of CTS done at 12 weeks after surgery. The Spanish DASH showed a responsiveness lower than the CTQ and higher than the SF-36 as a proof of a good construct validity.

In vitro susceptibilities of field isolates of Mycoplasma agalactiae.

In order to determine how widespread antibiotic resistance has become to standard treatments, the in vitro susceptibilities of 28 Mycoplasma agalactiae Spanish field isolates to 16 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials based on minimum inhibitory concentration (MIC)(90) values were fluoroquinolones, tetracyclines and macrolides. Two strains were tetracycline resistant. Streptomycin, erythromycin and nalidixic acid resistance was observed in all strains.

In vitro susceptibilities of Mycoplasma putrefaciens field isolates.

MICs were determined for 15 antimicrobial agents against 37 Mycoplasma putrefaciens isolates. The most effective antimicrobial drug classes were the fluoroquinolones, the tetracyclines, the lincosamide lincomycin, and the macrolides. The susceptibility profile of the isolates correlated with the geographic origin. This is the first report of decreased susceptibility to the macrolides, lincomycin, and the tetracyclines in M. putrefaciens strains.

Application of flow cytometry for the determination of minimal inhibitory concentration of several antibacterial agents on Mycoplasma hyopneumoniae.

AIM: In this study, flow cytometry was evaluated for the determination of the minimal inhibitory concentrations (MICs) of nine antibacterial agents (enrofloxacin, ciprofloxacin, oxytetracycline, chloramphenicol, tylosin, lincomycin, gentamycin, spectinomycin and streptomycin) against M. hyopneumoniae. METHODS AND RESULTS: Flow cytometry was able to detect Mycoplasma hyopneumoniae inhibition at 12 h postincubation, whereas the results obtained by the traditional method were only obtained at 48 h, when a visible change in the medium had occurred. At 48 h, both methods gave the same result for eight antibacterial agents, whereas flow cytometry gave slightly higher MIC values for one antibacterial agent (tylosin). This was attributed to the fact that the M. hyopneumoniae growth that had occurred in those tubes was not enough to visibly change the colour of the medium. A good relationship was found between the flow cytometry and the traditional method. CONCLUSION: Flow cytometry was found to be a good method for the determination of antimicrobial MICs in M. hyopneumoniae. SIGNIFICANCE AND IMPACT OF THE STUDY: The flow cytometric method allows the determination of the response of M. hyopneumoniae to each of the antibacterial agents in near real time, and has potential for the identification and study of resistant subpopulations.

In vitro susceptibilities of field isolates of Mycoplasma mycoides subsp. mycoides large colony type to 15 antimicrobials.

In vitro susceptibilities of 16 Mycoplasma mycoides subsp. mycoides large colony type field isolates to 15 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials were fluoroquinolones, tetracyclines and macrolides, with MIC values under 2 microg/ml. Resistance to nalidixic acid, gentamicin, streptomycin and spectinomycin was observed.

Characterisation of protein and antigen variability among Mycoplasma mycoides subsp. mycoides (LC) and Mycoplasma agalactiae field strains by SDS-PAGE and immunoblotting.

Mycoplasma mycoides subsp. mycoides (LC) (Mmm LC) and Mycoplasma agalactiae are the most important mycoplasma species involved in the contagious agalactia syndrome. A total of 25 field strains from Spain and the two type strains were analysed by SDS-PAGE and immunoblotting. Two polyclonal antisera (PAbs) raised against a pool of strains of each mycoplasma species were used. The results revealed a high degree of protein variability among the field strains. The type strain of Mmm LC appeared to be representative of the field strains of this species, whereas this was not the case with the M. agalactiae type strain. Whereas M. agalactiae is known to possess a gene family regulating surface antigen diversity, there is a need to study the mechanisms used byMmm LC to generate antigenic variability in more detail.

Use of flow cytometry for enumeration of Mycoplasma mycoides subsp. mycoides large-colony type in broth medium.

AIMS: The potential of using flow cytometry (FC) in combination with a fluorescent dye (SYBR green-I) for rapidly estimating Mycoplasma mycoides subSPS. mycoides large-colony type (MmmLC) in broth culture was examined. METHODS AND RESULTS: The FC analysis was performed by staining the MmmLC cells with a fluorescent dye, SYBR green-I (SYBR), and the results were compared with plate count method (colony forming units, - CFUs). There was a good correlation (linear regression, r(2) = 0.93) between mycoplasma counts determined by FC (cells ml(-1)) and by traditional plate count method (CFU ml(-1)). The lowest bacterial concentration detected by FC and traditional plate count was of the order of 10(4) cells ml(-1) and 10(3) CFU ml(-1), respectively. FC method allowed results in 20-30 min, whereas at least 24 h were necessary to obtain results with the traditional plate count method (CFU). CONCLUSION: Growth rates of MmmLC in broth medium determined by FC were highly reproducible and correlated well with mycoplasma counts assessed by the plate count method. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings suggest that FC could be a good alternative to replace other time-consuming techniques that are currently used to enumerate mycoplasma in broth medium, such as plate count method (CFU).

Microbiological survey for Mycoplasma spp. in a contagious agalactia endemic area.

In this work, we report a microbiological survey for Mycoplasma spp. undertaken between 2001 and 2002 in 28 goat herds in Gran Canaria, Spain, an area where contagious agalactia is endemic. All herds were randomly selected and represented approximately 15.5% of the total goat population of the island. A variable number of milk, articular and auricular swab samples were collected from each flock and cultured in specific mycoplasma culture media. There was a total of 38.5% positive flocks from which 37 mycoplasma isolates were obtained. In contrast with previous data obtained in Spain, our results showed that the large colony variant of M. mycoides subsp. mycoides (Mmm LC) was the most commonly isolated agent associated with contagious agalactia. This species was isolated from 90% of the positive herds and accounted for 54.1% of all isolations. M. agalactiae was isolated from 40% of the positive herds (27% of all isolations) and in six herds M. arginini was isolated (18.7% of all isolations). No M. capricolum or M. putrefaciens strains were isolated. Mycoplasmas were isolated from 21 milk samples, 15 ear canals swabs and one articular sample. The association of several species was reported in several herds. These results are at variance with previous serological studies, which indicated a higher disease prevalence, and suggest that it could be necessary to use detection techniques such PCR to confirm the existence of contagious agalactia in goats.