Evaluation of a rapid coliform detection kit from clinical mastitis milk using colloidal gold nanoparticle-based immunochromatographic strips

The accurate identification of mastitis‐causing bacteria assists in effective management by both dairy farmers and veterinarians and can be used to implement the selective use of antimicrobials for treatment. The purpose of this study was to evaluate the ability of our developed anti–ribosomal protein-L7/L12 antibody–coated immunochromatographic strip (ICS) test to detect coliforms in milk by comparing the results with the bacteriological culture method. We investigated the performance of the ICS test as compared with the bacteriological culture method using 308 milk samples from clinical bovine mastitis. First, to determine the optimal ICS test cutoff point for detecting coliform mastitis, we developed a receiver-operating characteristic curve. The result showed that the cutoff point was at 0.5 of our index. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value of the ICS test were 81.3%, 84.8%, 69.2%, and 91.54%, respectively. As the clinical signs increased in severity, the F-measure, a weighted harmonic mean of the sensitivity and overall PPV performance, increased. Because it is especially important to treat clinical mastitis appropriately in the early stages of detection, the ICS test, which can be used by both dairy farmers and veterinarians on dairy farms, is considered to be a useful tool for detecting coliform mastitis, which often presents with severe signs

Report of the Dry Valley Drilling Project, 1973-74

The Japanese researches participated in the Dry Valley Drilling Project (DVDP) in the McMurdo Sound region during the 1973-1974 summer season. This project was jointly organized by New Zealand, the United States of America and Japan, and started in the austral summer of 1971-1972 with preliminary investigations-the first phase-such as seismic soundings and aeromagnetic survey, which have been completed during the season. In the first phase, the Japanese researchers undertook electrical soundings, and in the second phase-1972-1973-carried out petrographic and chemical analyses of core samples taken from No. 1 and No. 2 bore holes on Ross Island. In the survey of the Dry Valley for the third phase, the Japanese researchers took special interest in the geochemical problems. The survey party consisted of four geochemists, a geologist and a geomorphologist. A technician for thin-sectioning and a field assistant were also included in order to make the best use of instruments such as an X-ray diffractometer, a thin-sectioner, polarized microscopes, etc. which were contributed by the Japanese to the Thiel Earth Science Laboratory in the McMurdo Station. From the latter part of October, 1973, five members including a technician and a field assistant examined core samples from No. 3 hole and carried out field works at the Lake Vanda (No. 4), Don Juan Pond (No. 5) and Lake Vida (No. 6) drilling sites. During the drilling at Lake Vida in the middle of December, three new members joined the party to work in rotation with members who had arrived earlier. They examined core samples from hole No. 6 and worked in the field at the Lake Fryxell and New Harbour sites. The Japanese were particularly interested in the hydrogeochemistry of the lakes the mineralogy of the salt deposits and secondary minerals and the isotope geology of volcanic core samples. Accordingly, the field work comprised the following tasks : 1) visual observations and descriptions of core samples, 2) collection of core samples to be chemically pre-treated, 3) identification of secondary minerals in core samples, 4) survey of the salt deposits in the vicinity of the drilling sites, 5) check of sequential changes in the chemical properties of the saline lakes, and 6) survey of bedrock geology. Some of the members also worked as site geologists

Thioester Synthesis through Geoelectrochemical CO2 Fixation on Ni Sulfides

Thioester synthesis by CO dehydrogenase/acetyl-CoA synthase is among the most ancient autotrophic metabolisms. Although the preceding prebiotic CO2 fixation routes to thioesters are often suggested, none has any experimentally supported evidence. Here we demonstrate that, under an electrochemical condition realizable in early ocean hydrothermal systems, nickel sulfide (NiS) gradually reduces to Ni0, while accumulating surface-bound CO due to CO2 electroreduction. The resultant partially reduced NiS facilitates thioester (S-methyl thioacetate) formation from CO and methanethiol even at room temperature and neutral pH. This thioester formation can further be enhanced up to a selectivity of 56% by NiS coprecipitating with FeS or CoS. Considering the central role of Ni in the enzymatic process mentioned above, our demonstrated thioester synthesis with the partially reduced NiS could have a direct implication to the autotrophic origin of life.<br /

Fertility risk factors in transferring Japanese Black embryos into dairy heifers: An epidemiological study

The aims of this study were 1) to summarize the current status of Japanese Black (JB) embryo transfer into Holstein heifers, which is carried out on a commercial basis in Japan, and 2) to reveal fertility risk factors, including those from the environment (year and season of transfer), recipient (age, number of transfers, clinical status of the ovaries) and embryo (quality, stage, state, genetic background). We used data from 4467 JB fresh or frozen embryo transfers into Holstein heifers conducted by Zen-noh Embryo Transfer Center during 2016–2018, and the differences in fertility risk due to factors related to the environment, recipient, and embryo were statistically evaluated. Differences in fertility risk due to each variable were observed, leading to significant differences in fertility with respect to year of transfer, embryo quality, embryo state, and embryo breed. These results suggest that the fertility of JB embryos might depend on differences in genetic background. There have been no previous reports of differences in embryo fertility due to the differences among JB\u27s bloodline combinations. In the future, overall reproductive efficiency must be monitored, including the effects of different bloodline combinations on the success of embryo recovery and transfer