Occurrence and survival of coliform bacteria, Escherichia coli and Salmonella in various manure and compost

pp. 865–874
Occurrence and survival of fecal-contamination indicator bacteria (coliform bacteria, Escherichia coli and Salmonella ) in various manure and compost samples collected from 23 composting facilities mostly in Kyushu were investigated by using selective media. Coliform bacteria were detected on desoxycholate agar from 11 (38%) of 29 product samples (15 cow dung manure, 4 poultry manure, 2 biosolid compost and 8 food waste compost) at a range of 10² to 10⁶ cfu g¹ dry matter. From positive samples, 21 isolates of possible coliform bacteria were purified. Among them, species of coliform bacteria ( E. coli , E. vulneria , Pantoea sp. and Buttiauxella agrestis ) were identified whereas isolates of Serratia marcescens , not coliform bacteria, were also obtained, suggesting that careful observation was necessary to avoid false positive counting due to the presence of a red colony of S. marcescens that resembled coliform bacteria. Isolates of E. coli were tested for slide aggregation with a set of antiserum against pathogenic E. coli serotypes and negative reaction was obtained for all the isolates tested. Direct detection of E. coli on Chromocult coliform agar and Salmonella on MLCB agar resulted in none and 2 (17%) of 12 samples tested, respectively. The fate of fecal-contamination indicator bacteria as above was followed during compost production on 7 cases at 6 compost facilities and 4 patterns were observed: fecal-contamination indicator bacteria 1) decreased and finally disappeared, 2) decreased once but re-growth was occurred on products, 3) decreased to some extent but remained in products, 4) was not detected throughout production. These results suggest that some fecal-contamination indicator bacteria may survive compost production and appropriate temperature control would be significant for hygiene control of manure and compost.     

Inactivation of Escherichia coli in soil by solarization

Contamination of agricultural soil by fecal pathogenic bacteria poses a potential risk of infection to humans. For the biosafety control of field soil, soil solarization in an upland field was examined to determine the efficiency of solarization on the inactivation of Escherichia coli inoculated into soil as a model microorganism for human pathogenic bacteria. Soil solarization, carried out by sprinkling water and covering the soil surface with thin plastic sheets, greatly increased the soil temperature. The daily average temperature of the solarized soil was 4–10°C higher than that of the non-solarized soil and fluctuated between 31 and 38°C. The daily highest temperature reached more than 40°C for 8 days in total in the solarized soil during the second and third weeks of the experiment. Escherichia coli in the solarized soil became undetectable (< 0.08 c.f.u. g⁻¹ dry soil) within 4 weeks as a result, whereas E. coli survived for more than 6 weeks in the non-solarized soil. Soil solarization, however, had little influence on the total direct count and total viable count of bacteria in the soil. These results indicate that soil solarization would be useful for the biosafety control of soil contaminated by human pathogens via immature compost or animal feces.     

A porcine lymphoma-derived cell line co-expressing IgM,IgG and IgA

A cell line (PL38PB) was established from blood samples of a 6-month-old pig that was diagnosed with lymphoma with CD5 expression. Histopathological examination revealed neoplastic lesions in the spleen, liver and lymph nodes. Tumor cells were immunohistochemically positive for CD20 and immunoglobulin heavy chains (μ, γ and α). Membranous CD5 and cytoplasmic Immunoglobulin M (IgM), ​Immunoglobulin G (IgG) and ​Immunoglobulin A (IgA) were detected in PL38PB cells by flow cytometry. In addition, the cytoplasm of PL38PB cells were positive for IgM, IgG and IgA by immunofluorescent. However, no Ig secretion was detected in culture supernatant by Ouchterlony gel diffusion method. Results suggest that PL38PB cells express three Ig isotypes that are produced but not secreted.     

Antigen-specific histamine release in dogs with food hypersensitivity

An in vitro evidence of IgE-mediated hypersensitivity to food allergens was detected by positive results of antigen-specific histamine release in dogs with food hypersensitivity. Eight dogs were diagnosed to have food hypersensitivity based on identification of offending food allergens with food elimination followed by oral food provocation. The percentages of histamine release against the stimulation of offending food allergens in the cases ranged from 2.1% to 70.9%. Six of the 8 cases showed histamine release higher than those of healthy control dogs. Four dogs showed relatively high histamine release at the percentage beyond 10% that was compatible with a positive value of histamine release in humans with food hypersensitivity. These findings would suggest that IgE-mediated hypersensitivity against food allergens could be involved in canine food hypersensitivity.     

Maximum permissible load for Kiso horses trotting over a short,straight course

This study aimed to determine the load‐bearing capacity of trotting Kiso horses using gait analysis. Ten Kiso horses with a height at withers of 128 cm were included. Their riders were fitted with a marker (70 mm in diameter placed on their chest) recorded by two digital DVD cameras while trotting along a short, straight course. In total, eight tests were performed for each horse: the first with a 70 kg load; six with randomly loaded weights ranging 80–130 kg; and then a final test again with a 70 kg load. Three‐dimensional movement of the marker was analyzed using a motion capture system. The time series of vertical displacement of the marker underwent spectrum analysis by the maximum entropy method, and the autocorrelation coefficient was calculated. The first two peaks of the autocorrelation were defined as symmetry and regularity, and their sum was defined as stability. Regularity in the 120 kg test (0.54) was lower than that in the first 70 kg test (0.61), and stability in the 120 kg test (1.31) was lower than that in the first 70 kg test (1.42). We concluded that the maximum permissible load for a trotting Kiso horse is < 120 kg, which represents 31% of its bodyweight.     

Concentration of cephalothin in body fluids and tissue samples of Thoroughbred horses

Cephalothin (CET) concentrations in body fluids (plasma, synovial fluid, pleural fluid, peritoneal fluid, and aqueous humor) and tissue samples (bone, lung, jejunum, hoof, and subcutaneous tissue) were investigated to consider the treatment of infectious diseases in horses. CET 22 mg/kg body weight was intravenously administered to 12 horses. Samples were collected from four different horses at 1, 3, and 5 hr after administration. The CET concentration in body fluids other than aqueous humor was maintained above the MIC₉₀ values of Streptococcus zooepidemicus and Staphylococcus aureus until 5 hr, but it was not maintained above that of S. aureus in bone. CET (22 mg/kg twice a day) is effective for septic arthritis, pleuritis, and peritonitis caused by gram-positive bacteria but ineffective for osteomyelitis.     

Potassium distribution in black heartwood of sugi (Cryptomeria japonica) I: Localization in axial parenchyma cells

This is the first report to ascertain potassium location in black heartwood of sugi (Cryptomeria japonica). The objective of this study was to understand the distribution of potassium in sugi black heartwood in connection with anatomical morphology. Scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDXA) was used to investigate the distribution of inorganic elements, especially potassium. In black heartwood, potassium was detected in all tissues (tracheids, ray parenchyma, and axial parenchyma), but its concentrations were different in each xylem tissue. Potassium was particularly accumulated in the droplets in axial parenchyma cells. In addition, calcium was also detected in all tissues. Phosphorus sometimes existed in the granules in ray parenchyma cells. From optical microscopy, the axial parenchyma cells were observed to be arranged in a tangential direction on transverse section and the droplets in these cells were distributed in areas of high ash and green moisture content. For red heartwood, potassium detected by SEM-EDXA was far lower in all tissues than in the black heartwood, while the trend for calcium was the converse. Potassium in axial parenchyma cells was more abundant in black heartwood than in typical pale red heartwood.     

Screening of therapeutic targets for canine mast cell tumors from a variety of kinase molecules

Options of systemic treatment for canine MCT have been still limited and most canine cases with MCTs eventually undergo relapses even after achievement of a remission. Thus additional therapies are required to establish for the tumor. To identify the novel candidate therapeutic targets for canine MCT, the mRNA expression and phosphorylation statuses of several receptor or non-receptor kinases as well as the inhibitory effect of 95 specific inhibitors on the growth were assessed in three canine MCT cell lines (HRMC, VIMC1 and CMMC1). Among the 14 targets, the mRNAs of 11, 7 and 7 kinases were amplified in HRMC, VIMC1 and CMMC1, respectively. The mRNAs of VEGFR3, PDGFRα, SRC, YES, LCK and FYN were detected in all cell lines. The phosphorylation of 12, 8 and 7 kinases was observed by using specific antibody arrays in HRMC, VIMC1 and CMMC1, respectively. DTK, EPHB6, AMPKα1, CREB, STAT5a and STAT5b were phosphorylated in all cell lines. The 10, 9 and 17 inhibitors exhibited the biological activity against the growth of HRMC, VIMC1 and CMMC1, respectively. Only three inhibitors such as SB218078 (for Chk1), PDGF RTK inhibitor IV (for PDGFR) and radicicol (for Hsp90) suppressed the growth of all three cell lines. The present study indicated that several kinases, such as Chk1, PDGFR and Hsp90, could be used as therapeutic targets in the treatment for canine MCT. Further studies and clinical trials are warranted to apply the inhibitors for the treatment of the tumor.     

Decreased gallbladder emptying in dogs with biliary sludge or gallbladder mucocele

Biliary sludge in dogs is dismissed commonly as an incidental finding. On the other hand, gallbladder mucocele is reported increasingly in dogs and can lead to biliary obstruction or gallbladder rupture. Cholestasis is suspected to play a role in development of sludge and mucoceles, though there are no data in dogs to support this. We investigated gallbladder emptying, a key factor in biliary flow, in dogs with mobile sludge, immobile sludge, or gallbladder mucocele and in healthy controls. Gallbladder ejection fraction estimated by ultrasonography was used as the index of gallbladder emptying. The ejection fraction at 60 min after eating was significantly decreased in all three abnormal groups. Moreover, all dogs with sludge or a mucocele had gallbladder distension. These changes were the greatest in the mucocele group. Thus, biliary stasis occurs not only in dogs with gallbladder mucocele but also in dogs with biliary sludge. Cholestasis may play a role in the pathogenesis or progression of these diseases in dogs.     

Development of an efficient method for recovery of Puumala and Puumala-related viruses by inoculation of Mongolian gerbils

Puumala (PUU) virus and PUU-related viruses are difficult to isolate in cell culture. To determine whether animal inoculation would be a better alternative for virus recovery, the Sotkamo strain of PUU virus was inoculated into several animal species. Newborn Mongolian gerbils (MGs), mice, and rats were infected with the Sotkamo strain by intracerebral (ic), intraperitoneal (ip), and subcutaneous (sc) inoculation. Antibodies to PUU appeared in MGs at 30 days post-infection (dpi), and in mice and rats at 15 dpi. Interestingly, virus appeared at 7 dpi in lung and brain of MGs inoculated via ic and ip routes. Virus was detected in all tested tissues of MGs at 15 dpi, with a peak level of 1.36 x 10 (5) focus forming units (FFU)/g in brain tissue. The virus titer declined with the onset of the antibody response and became undetectable by 75 dpi, when the antibody titer reached the maximum level. The appearance of the virus in mice and rats was delayed as compared to MGs, and the virus titer was apparently lower, at approximately 4 to 8 x 10(3) FFU/g, at 15 dpi. In addition, lung homogenates of antibody-positive Clethrionomys (C.) rufocanus (captured in Tobetsu, Hokkaido, Japan) were inoculated into MGs by the ic route. PUU-related viral RNA was detected at 16 dpi in the brains of MG inoculated with the lung homogenate, and antibodies were detected at 45 dpi. These findings indicate that newborn MG inoculation is an efficient method to recover PUU and PUU-related viruses.