Prey selection of common minke (Balaenoptera acutorostrata) and Bryde's (Balaenoptera edeni) whales in the western North Pacific in 2000 and 2001

A study of common minke and Bryde's whales was conducted in the western North Pacific in the 2000 and 2001 summer seasons to estimate prey selection of cetaceans as this is an important parameter in ecosystem models. Whale sighting and sampling surveys and prey surveys using quantitative echosounder and mid‐water trawl were carried out concurrently in the study. Biomasses of Japanese anchovy, walleye pollock and krill, which were major prey species of common minke and Bryde's whales, were estimated using an echosounder. The results suggested that common minke whale showed prey selection for Japanese anchovy while they seemed to avoid krill in both the offshore and coastal regions and walleye pollock in the continental shelf region. Selection for shoaling pelagic fish was similar to that in the eastern North Atlantic. Bryde's whale showed selection for Japanese anchovy in August 2000 and July 2001, while it showed prey selection for krill in May and June in 2001.     

Characterization of Aerococcus viridans isolated from milk samples from cows with mastitis and manure samples

Thirty-eight Aerococcus viridans isolates were obtained from milk from 478 cows with clinical mastitis in a farm during the periods between November 2011 and February 2012, and between December 2012 and March 2013. Additional isolates were obtained from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding materials. The processed manure was later used to cover the floor of the stalls in barns as bedding materials. The temperatures recorded in the composted and processed manure were not as high as those generally observed during satisfactory composting. To reveal the association of A. viridans in manure-related products with intramammary infection in cows, isolates were characterized by their DNA fragment patterns as determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility testing. Isolates obtained from milk, processed manure and bedding materials had identical DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to clindamycin, whereas virtually all the isolates were susceptible to 12 other antimicrobials including cefalosporins that have been used to treat bovine mastitis in Japan. In vitro, three A. viridans isolates from milk and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high temperature (50°C). The results suggest that the processed manure and bedding materials in this farm were possible sources of A. viridans that caused infection in the cows with mastitis.     

Empirical Percentile Growth Curves with Z-scores Considering Seasonal Compensatory Growths for Japanese Thoroughbred Horses

Percentile growth curves are often used as a clinical indicator to evaluate variations of children’s growth status. In this study, we propose empirical percentile growth curves using Z-scores adapted for Japanese Thoroughbred horses, with considerations of the seasonal compensatory growth that is a typical characteristic of seasonal breeding animals. We previously developed new growth curve equations for Japanese Thoroughbreds adjusting for compensatory growth. Individual horses and residual effects were included as random effects in the growth curve equation model and their variance components were estimated. Based on the Z-scores of the estimated variance components, empirical percentile growth curves were constructed. A total of 5,594 and 5,680 body weight and age measurements of male and female Thoroughbreds, respectively, and 3,770 withers height and age measurements were used in the analyses. The developed empirical percentile growth curves using Z-scores are computationally feasible and useful for monitoring individual growth parameters of body weight and withers height of young Thoroughbred horses, especially during compensatory growth periods.     

T4-type bacteriophage communities estimated from the major capsid genes (g23) in manganese nodules in Japanese paddy fields

The present study compared the capsid gene ( g23 ) of T4-type bacteriophages (phages) in Mn nodules with those in the plow layer soil and subsoils of two Japanese paddy fields by applying the primers MZIA1bis and MZIA6 to DNA extracts from the nodules and soils. The deduced amino acid sequences of the g23 genes in the Mn nodules were similar to those in the plow layer soil and in the subsoils. This result indicated that similar T4-type phage communities developed at these sites and that the diversity of T4-type phage communities was wide enough to cover those in the plow layer soil and in the subsoils. The majority of g23 clones formed several clusters with the clones and phages obtained from far-apart paddy fields, and the sequences of two clones were completely identical to a phage and a clone from other paddy fields at the nucleotide or amino acid level, indicating horizontal transfer of g23 genes between those paddy fields. A clone with a long nucleotide residue (686 bp) and a distribution remote from the other clones in the phylogenetic tree indicated that there were many uncharacterized, novel g23 genes in the paddy fields.     

IMPACT OF TISSUE INHOMOGENEITY ON DOSE DISTRIBUTION IN THE CANINE CARPAL AND TARSAL REGIONS FOR COBALT AND 6 MV PHOTONS

We quantified the effect of tissue inhomogeneity on dose distribution in a canine distal extremity resulting from treatment with cobalt photons and photons from a 6 MV accelerator. Monitor units for a typical distal extremity treatment were calculated by two methods, using equally weighted, parallel-opposed fields. The first method was a computed tomography (CT)-based, computerized treatment plan, calculated without inhomogeneity correction. The second method was a manual point dose calculation to the isocenter. A computerized planning system was then used to assess the dose distribution achieved by these two methods when tissue inhomogeneity was taken into account. For cobalt photons, the median percentage of the planning target volume (PTV) that received <95% of the prescribed dose was 4.5% for the CT-based treatment plan, and 26.2% for the manually calculated plan. For 6 MV photons, the median percentage of the PTV that received <95% of the prescribed dose was <1% for both planning methods. The PTV dose achieved without using inhomogeneity correction for cobalt photons results in potentially significant under dosing of portions of the PTV.     

Methanogenic archaeal communities developed in paddy fields in the Kojima Bay polder, estimated by denaturing gradient gel electrophoresis, real-time PCR and sequencing analyses

Methanogenic archaeal communities inhabiting the paddy field soils in the Kojima Bay polder were investigated using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), real-time PCR and sequencing analyses. Soil samples of the plow and subsoil layers were collected in 2006 from four paddy fields that were reclaimed between 1692 and 1954. The DGGE band patterns of the targeted 16S rRNA genes amplified from the extracted DNA from the samples were different from the patterns from the paddy field soils in diluvial and alluvial areas. The numbers of targeted 16S rRNA genes, which were involved with methanogenic archaeal and other archaeal sequences, were approximately 10⁷–10⁸ and 10⁶ g⁻¹ dry soil in the plow and subsoil layers, respectively. Sequences of methanogenic archaeal 16S rRNA genes belonging to Methanocellales (Rice cluster I), Methanosarcinales and Methanobacteriales were obtained from the major DGGE bands. Whereas sequences in Methanomicrobiales, which were predominant methanogens in the diluvial and alluvial paddy fields, were not recovered. Known halophilic and methylotrophic methanogens, which are characteristic of saline and marine environments, were not detected. These results indicate that distinctive methanogenic archaeal communities have developed in the paddy field soils in the Kojima Bay polder.