Is the effectivity of copper ions treatment of milk enough to block Mycobacterium avium subsp. paratuberculosis infection in calves?

Milk is an important transmission route of Mycobacterium avium subsp. paratuberculosis (MAP) for dairy calves. Given its resistance to pasteurization, alternative milk treatments are needed to control MAP transmission via milk. The present study reports the evaluation of a novel milk decontamination treatment based on copper ions as a means of preventing infection in dairy calves. Ten newborn calves were assigned to one of two experimental groups (n=5) which were studied for 1 year. The first group was fed milk naturally contaminated with MAP and the second one received the same milk but after being treated with copper ions. In both groups, milk MAP load was estimated. The progression of the infection was monitored monthly and at the end of the study, calves were euthanised, and tissue samples were examined both grossly and by histopathology. The treatment of milk with copper ions significantly reduced the number of viable MAP. Faecal shedding of MAP was observed in both study groups, but the calves fed naturally contaminated milk began to shed MAP earlier. Only calves fed copper-treated milk showed histopathological evidence consistent with MAP infection. The latter offers more questions than answers, and maybe the presence of a more tolerant and virulent MAP strain could be the final answer to this situation

In vitro inactivation of <i>Mycobacterium avium</i> subsp. <i>paratuberculosis </i>(MAP) by use of copper ions

Abstract Background Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of paratuberculosis, a contagious infectious disease that affects domestic and wild ruminants causing chronic inflammation of the intestine. MAP has proven to be very resistant to both physical and chemical processes, making it difficult to control this pathogen. Based on the recognized antimicrobial properties of copper, the objective of this study was to evaluate the effectiveness of copper ions to reduce MAP numbers and/or MAP viability in a fluid matrix. Besides, methicillin-resistant Staphylococcus aureus (MRSA), and Escherichia coli were used as controls of the effectiveness of copper ions. MAP-spiked PBS was subjected to copper ions treatment at 24 V for 5 min and the PBS suspensions were sampled before and after treatment. MAP viability and quantification were determined using three complementary techniques: a phage amplification assay, MGIT culture and qPCR. Results Moderate numbers (103 CFU ml−1) of the two control bacteria were completely eliminated by treatment with copper ions. For MAP, copper ions treatment reduced both the viability and numbers of this pathogen. Phage assay information quickly showed that copper ions (24 V for 5 min) resulted in a significant reduction in viable MAP. MGIT culture results over time showed statistically significant differences in time-to-detection (TTD) values between PRE and POST treatment. MAP genome equivalent estimates for PBS suspensions indicated that MAP numbers were lower in samples POST-treatment with copper ions than PRE-treatment. Conclusions The use of copper ions resulted in a significant reduction of MAP in a liquid matrix, although some MAP survival on some occasions was observed

The TESS-Keck Survey. VIII. Confirmation of a Transiting Giant Planet on an Eccentric 261 Day Orbit with the Automated Planet Finder Telescope

We report the discovery of TOI-2180 b, a 2.8 $M_{\rm J}$ giant planet orbiting a slightly evolved G5 host star. This planet transited only once in Cycle 2 of the primary Transiting Exoplanet Survey Satellite (TESS) mission. Citizen scientists identified the 24 hr single-transit event shortly after the data were released, allowing a Doppler monitoring campaign with the Automated Planet Finder telescope at Lick Observatory to begin promptly. The radial velocity observations refined the orbital period of TOI-2180 b to be 260.8$\pm$0.6 days, revealed an orbital eccentricity of 0.368$\pm$0.007, and discovered long-term acceleration from a more distant massive companion. We conducted ground-based photometry from 14 sites spread around the globe in an attempt to detect another transit. Although we did not make a clear transit detection, the nondetections improved the precision of the orbital period. We predict that TESS will likely detect another transit of TOI-2180 b in Sector 48 of its extended mission. We use giant planet structure models to retrieve the bulk heavy-element content of TOI-2180 b. When considered alongside other giant planets with orbital periods over 100 days, we find tentative evidence that the correlation between planet mass and metal enrichment relative to stellar is dependent on orbital properties. Single-transit discoveries like TOI-2180 b highlight the exciting potential of the TESS mission to find planets with long orbital periods and low irradiation fluxes despite the selection biases associated with the transit method.Comment: Published in A