Development of a method for detecting Coxiella burnetii in cheese samples     

Hirai A  Nakama A  Chiba T  Kai A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(2):175-180

Coxiella burnetii is the causative agent of Q fever, and the main route of infection in humans is inhalation of contaminated aerosols. Although oral transmission by contaminated raw milk or dairy products is also a possible route of human infection, there have been few studies investigating the presence of C. burnetii in dairy products. We developed a new method of extracting DNA from cheese and detecting C. burnetii DNA in cheese samples with a nested PCR assay. The limit of detection was 6.0 × 10(2) C. burnetii particles per gram. We subsequently used this method to examine the presence of C. burnetii in cheese at commercial markets in Tokyo from June 2005 to December 2008. Twenty-eight of 147 cheese samples were found to be positive for C. burnetii DNA. However, when we assessed the viability of C. burnetii by inoculating mice with DNA-positive samples, all of the samples were found to be negative. Thus, the viability of C. burnetii appears to have been lost in these cheese samples.  相似文献   

Vertical Transmission of Brucella abortus Causes Sterility in Pregnant Mice     

Hashino M  Kim S  Tachibana M  Shimizu T  Watarai M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1075-1077

The mechanisms of abortion and sterility induced by bacterial infection are largely unknown. In the present study, we found that Brucella abortus, a causative agent of brucellosis and facultative intracellular pathogen, caused sterility in pregnant mice. We have recently established a mouse model for abortion induced by B. abortus infection and high rates of abortion are observed for bacterial infection on day 4.5 of gestation, but not for other days. Infected newborn (first generation) mice showed poor growth compared with uninfected newborn mice and bacterial replication in the spleen of the former was observed over a long period. When infected first generation female mice were mated to infected first generation male mice, the number of fetuses was significantly less than that in uninfected first generation mice. These infected second generation mice also showed poor growth. These results suggest that vertical transmission of B. abostus causes sterility in pregnant mice and our mouse model would be useful for the investigating of brucellosis.  相似文献   

Estimation of glomerular filtration rate in calves using the contrast medium iodixanol     

Imai K  Yamagishi N  Okura N  Fukuda T  Hirata T  Okada K  Sato S  Furuhama K 《Veterinary journal (London, England : 1997)》2012,193(1):174-179

To develop a simple procedure for estimating glomerular filtration rate (GFR) in calves, a three-sample method using iodixanol was first compared to that using the standard agent inulin. Iodixanol and inulin were co-administered intravenously to calves at 40 mg I/kg and 40 mg/kg, respectively, and blood was collected 30, 60, 120, and 180 min later. Serum iodixanol and inulin concentrations were separately determined by high performance liquid chromatography and colorimetry. Serum urea nitrogen (UN) and creatinine concentrations were also measured. GFR estimated by iodixanol was consistent with that using inulin in clinically healthy calves. Based on GFR estimations in healthy calves and those renal-loaded with iodixanol, it was found that the serum creatinine concentrations became elevated when GFR decreased to 60% of the reference value. In contrast, serum UN concentrations fluctuated widely, presumably due to extra-renal factors. When GFR was estimated using the three-sample method and compared with the single-blood-sample method, 62/69 (90%) of samples tested were within the agreement plots. The results demonstrated that the single-blood-sample method using iodixanol may be useful in monitoring GFR in calves.  相似文献   

Efficacy of a single intravenous dose of the neuraminidase inhibitor peramivir in the treatment of equine influenza     

Yamanaka T  Bannai H  Nemoto M  Tsujimura K  Kondo T  Muranaka M  Hobo S  Minamijima YH  Yamada M  Matsumura T 《Veterinary journal (London, England : 1997)》2012,193(2):358-362

Equine influenza A virus (EIV) of the H3N8 subtype is an important pathogen causing acute respiratory disease in horses. Peramivir is a selective inhibitor of the influenza virus neuraminidase (NA). The characteristics of peramivir are not only its capacity for parenteral administration, but also its strong affinity for NA and slow off-rate from the NA-peramivir complex, suggesting that it could lead to a prolonged inhibitory effect and thus allow a lower dosing frequency. The aims of this study were to evaluate the inhibitory efficacy of peramivir against the NA activities of EIV in vitro and the treatment efficacy of a single intravenous dose of peramivir in horses experimentally infected with EIV. Peramivir inhibited the activities of NA from the seven contemporary EIV strains in vitro, with 50% inhibitory concentrations ranging from 0.10 to 0.20nmol/L. Horses treated with a single IV dose of peramivir (3000mg/600mL/animal, 7.8-9.3mg/kg of bodyweight) showed significantly milder clinical signs (pyrexia, nasal discharge and cough) with a shorter duration than control horses injected with normal saline. Moreover, the mean duration of virus shedding for the horses treated with peramivir was significantly shorter than for the control horses. These findings suggested that a single IV administration of peramivir had good potential for the treatment of equine influenza, and may help to limit the spread of the disease in the horse population.  相似文献   

Evidence for estrogen receptor expression during medullary bone formation and resorption in estrogen-treated male Japanese quails (Coturnix coturnix japonica)     

Shinji Hiyama  Toshie Sugiyama  Seiji Kusuhara  Takashi Uchida 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(3):223-227

The temporal expression of estrogen receptor (ER)-α and ER-β mRNA was examined in male Japanese quails. Femurs of quails receiving 17β-estradiol underwent RTPCR and histochemical analysis 1 to 15 days after treatment. Untreated quails were used as controls (day 0). Between days 0 and 5, cells lining the bone endosteal surface differentiated into osteoblasts, which in turn formed medullary bone. Expression of ER-α was already observed on day 0 and increased slightly during bone formation whereas ER-β was hardly detected throughout this process. After osteoclasts appeared on the medullary bone surface, this type of bone disappeared from the bone marrow cavity (days 7~15). ER-α expression simultaneously decreased slightly and ER-β levels remained very low. These results suggest that estrogen activity mediated by ER-α not only affects medullary bone formation but also bone resorption.  相似文献   

Effects of single-tree selection harvesting on hymenopteran and saproxylic insect assemblages in the canopy and understory of northern temperate forests     

Sandy M. Smith  Nurul Islam  M. Isabel Bellocq 《林业研究》2012,23(2):275-284

Insects respond to changes in microhabitat caused by canopy disturbance, and thus can be used to examine the ecological impacts of harvesting. Single-tree selection harvesting is the most common silvicultural system used to emulate local small-scale natural disturbance and maintain uneven-aged forest structure in temperate forests. Here, we test for differences in richness, abundance, and composition of hymenopteran and saproxylic insect assemblages at four different taxon levels (selected insect orders; and all hymenopteran families, and braconid subfamilies and morphospecies) between the canopy and understory of unharvested and single-tree selection harvested sites in a northern temperate forest from central Canada. Harvesting had no effect on insect assemblage richness, composition or abundance at the three highest taxon levels (order, family and subfamily). Similarly, richness and abundance at the lowest-taxon level (braconid morphospecies) were similar, although composition differed slightly between unharvested and harvested stands. Insect assemblages were vertically stratified, with generally higher abundance (for Diptera, Hymenoptera, some hymenopteran families and braconid subfamilies) and richness (for braconid morphospecies) in the understory than the canopy. In particular, composition of the braconid morphospecies assemblage showed relatively low similarity between the understory and canopy. Single-tree selection harvesting appears to influ-ence wood-associated insect taxa only subtly through small changes in community composition at the lowest taxon level, and thus is recommended as a conservative approach for managing these northern temperate forests.  相似文献   

Diameter and death of whorl and interwhorl branches in Atlas cedar (<Emphasis Type="Italic">Cedrus atlantica</Emphasis> Manetti): a model accounting for acrotony     

François Courbet  Jean-Christophe Hervé  Etienne K. Klein  Francis Colin 《Annals of Forest Science》2012,69(2):125-138

• Introduction   

Branch size and branch status (dead or alive) are important characteristics closely related to tree growth and wood quality. The aim of this study was to design models for the diameter and status of branches in Atlas cedar (Cedrus atlantica Manetti).  相似文献   

Modeling of light transmission under heterogeneous forest canopy: an appraisal of the effect of the precision level of crown description     

David Da Silva  Philippe Balandier  Frédéric Boudon  André Marquier  Christophe Godin 《Annals of Forest Science》2012,69(2):181-193

• Context  

Light availability in forest understory is essential for many processes; it is, therefore, a valuable information regarding forest management. However, its estimation is often difficult and direct measurements are tedious. Models can be used to compute understory light, but they often require a lot of field data to accurately predict light distribution, particularly in the case of heterogeneous canopies.  相似文献   

A review of decision-making approaches to handle uncertainty and risk in adaptive forest management under climate change     

Rasoul Yousefpour  Jette Bredahl Jacobsen  Bo Jellesmark Thorsen  Henrik Meilby  Marc Hanewinkel  Karoline Oehler 《Annals of Forest Science》2012,69(1):1-15

• Context  

This review paper provides an overview of approaches to which we may resort for handling the complex decision problems involving uncertainty and risk that climate change implies for forest managers. Modelling approaches that could support adaptive management strategies seem to be called for, not only as climate change denotes increased economic uncertainty but also because new and more reliable information becomes available as time passes and climate changes.  相似文献   

Drought and frost resistance of trees: a comparison of four species at different sites and altitudes     

Katline Charra-Vaskou  Guillaume Charrier  Rémi Wortemann  Barbara Beikircher  Hervé Cochard  Thierry Ameglio  Stefan Mayr 《Annals of Forest Science》2012,69(3):325-333

Context   

Drought and frost resistances are key factors for the survival and distribution of tree species.  相似文献