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41.
Parentage testing was performed in sixteen litters by canine artificial inseminations with frozen semen from different sires on Days 5 and 7 after the LH surge. It became apparent that only 25% of dams had superfecundation, but 43.8% of dams were whelped after insemination only on Day 5 after the LH surge and 31.3% of dams after insemination only on Day 7. Of the total 87 puppies, 46% were born after insemination on Day 5 after the LH surge and 54% after insemination on Day 7. This result strongly suggested that canine artificial insemination with frozen semen could be sufficiently successful also on Days 5 and 7 after the LH surge.  相似文献   
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The effects of streptozotocin (STZ)-induced diabetes on induction of hepatic preneoplastic lesions by diethylnitrosamine (DEN) were investigated in male Fischer rats. A single dose of STZ was injected intravenously either 2 weeks before or after initiation with DEN. The blood glucose levels were significantly elevated from 1 week after STZ-injection until autopsy. The numbers of GST-P positive foci at 1 week after DEN administration in the STZ-injected rats were similar to those in the non-diabetic rats. In contrast, both the numbers and areas of GST-P positive foci > 2 mm in diameter 8 weeks after DEN administration were increased significantly in the rats treated with STZ after DEN exposure compared with the non-diabetic control rats. The results suggest that hepatic preneoplastic lesions initiated with DEN are promoted by STZ treatment-inducing diabetes.  相似文献   
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Spatial and temporal variation in copepod community structure, abundance, distribution and biodiversity were examined in the western subarctic North Pacific (40–53°N, 144–173°E) during 2001–2013. Continuous Plankton Recorder (CPR) observational data during the summer season (June and July) were analyzed. The latitudinal distribution of warm‐water species in June shifted northward after 2011 while no apparent latitudinal shift of cold‐water and other species was observed. Species number and the Shannon–Wiener biodiversity index (H′) in June tended to increase in the northern area after 2011. The warm‐water species abundance and center latitude of warm‐water distribution were positively correlated with sea surface temperature (SST) across sampling locations, whereas no significant correlations with SST were observed for cold‐water species or other species. Warm SSTs in June after 2011 appeared to cause the northward shift of warm‐water species distribution, which in turn contributed to the higher biodiversity in the northern area. This study demonstrated the rapid response of warm‐water species to warm SST variation, whereas cold‐water and other species did not exhibit such clear responses. These findings indicate that the response of copepods to environmental changes differs among copepod species, highlighting the importance of investigating lower trophic levels to the species level to evaluate individual species’ responses to climate change.  相似文献   
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In the present study, we tried to detect protozoan blood parasites from the liver or blood of 141 Japanese sika deer (Cervus nippon) in Iwate Prefecture of Japan by polymerase chain reaction. Approximately 500-bp amplicons were obtained in 76 (53.9%) of 141 samples by amplification for V4 hyper-variable regions of the 18S rRNA gene, and the amplicons were considered to be DNA of Theileria species. The complete nucleotide sequences (1701-bp) of the 18S rRNA gene were determined in 25 samples and were divided into 8 genotypes that were phylogenetically separated into two distinct lineages showing a monophyletic relation. The two lineages of Theileria were detected in different rates (12 and 88%) from sika deer in Iwate Prefecture.  相似文献   
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ABSTRACT: The effect of reward level (amount of food received in response to one trigger actuation) on the self-feeding activity of juvenile yellowtails was examined. Three groups of 10 juvenile yellowtails (mean bodyweight, 65.6 g) were allocated randomly to three 200 L cylindrical tanks set in the experiment room. Each tank was illuminated by overhead fluorescent lamps with a light : dark photoperiod regimen of 12 h : 12 h (light 06.00–18.00 hours). A rod-type tactile switch was used to activate the self-feeding device. Three levels of reward were set up by installing a different number of identical feeders for each group: one feeder for the low-reward group, three feeders for the medium-reward group and five feeders for the high-reward group. Each feeder delivered 3–7 pellets per actuation. Yellowtails in all groups showed a clearly diurnal feeding pattern that was synchronized to the given photoperiod. Average number of feeder actuations per day was highest (219/day) in the low-reward group. Second highest was the medium-reward group (116/day), and last was the high-reward group (67/day). The resultant average feed intake per day was 27.1 g/day in the low-reward group, 31.5 g/day in the medium-reward group and 28.4 g/day in the high-reward group. Thus, yellowtails appear to have the ability to regulate the amount of feed delivered daily by increasing the number of food demands when the reward is low and decreasing the number of food demands when the reward is high.  相似文献   
48.
Canine parentage testing based on microsatellite polymorphisms.   总被引:4,自引:0,他引:4  
To establish an accurate method for parentage testing in dogs, microsatellite DNA repeat length polymorphisms were examined. We selected twenty microsatellite markers reported previously and examined their application for parentage testing in Beagles and Labrador Retrievers. Heterozygosity (He), Polymorphism Information Content (PIC), the probabilities of Paternity Exclusion (PE) and the combined PE were calculated from allelic frequencies of the markers. All markers amplified by polymerase chain reactions were polymorphic and many markers showed high He and PIC in the both breeds. The final combined PEs in Beagles and Labrador Retrievers were 0.999994 and 0.999920, respectively. The results suggest that the twenty markers can be applied for routine parentage testing in dogs.  相似文献   
49.
One calf died (No. 1) and another was euthanized following astasia (No. 2). Histopathological examination revealed suppurative meningoencephalitis in these calves. Klebsiella pneumoniae antigens were detected in lesions. Thymocytes were decreased in the thymus cortex in both cases. 16S rRNA gene sequencing of the No. 1 isolate and bacterial extracts from formalin fixed paraffin embedded sections of No. 2 revealed that both samples were K. pneumoniae. The No. 1 isolate showed multidrug resistance against penicillin antibiotics, fosfomycin, streptomycin, macrolide antibiotics, tetracycline antibiotics, and clindamycin. Immunosuppression is a significant septicemic K. pneumoniae infection risk factor. Our study provides new aspects regarding K. pneumoniae infections in cattle, bacterial meningoencephalitis differentiation, and K. pneumoniae and bacterial meningoencephalitis treatments.  相似文献   
50.
BACKGROUND: Trichoderma asperellum SKT-1 is a microbial pesticide of seedborne diseases of rice. To investigate the mechanisms of disease suppression in SKT-1, the ability to induce systemic resistance by SKT-1, or its cell-free culture filtrate (CF), was tested using Arabidopsis thaliana Col-0 plants. RESULTS: Both SKT-1 and its CF elicit an induced systemic resistance against the bacterial leaf speck pathogen Pseudomonas syringae pv. tomato DC3000 in Col-0 plants. Involvement of plant hormones in the induced resistance by SKT-1 and CF was assessed using Arabidopsis genotypes such as the jasmonic acid (JA)-resistant mutant jar1, the ethylene (ET)-resistant mutant etr1, the plant impaired in salicylic acid (SA) signalling transgenic NahG and the mutant npr1 impaired in NPR1 activity. In soil experiments using SKT-1, no significant disease suppression effect was observed in NahG transgenic plants or npr1 mutant plants. Expression levels of SA-inducible genes such as PR-1, PR-2 and PR-5 increased substantially in the leaves of Col-0 plants. Expression levels of JA/ET-induced genes such as PDF1.2a, PR-3, PR-4 and AtVsp1 were also induced, but the levels were not as high as for SA-inducible genes. In a hydroponic experiment using CF from SKT-1, all Arabidopsis genotypes showed an induced systemic resistance by CF and increased expression levels of JA/ET- and SA-inducible genes in leaves of CF-treated plants. CONCLUSION: The SA signalling pathway is important in inducing systemic resistance to colonisation by SKT-1, and both SA and JA/ET signalling pathways combine in the signalling of induced resistance by CF. These results indicate that the response of A. thaliana is different from that found in root treatments with barley grain inoculum and CF from SKT-1. Copyright © 2011 Society of Chemical Industry  相似文献   
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