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Simple diagnosis by ethanol immersion (SDEI) to detect Glomerella cingulata was used to detect three other fungi that also cause latent infection of strawberry plants. Signs on strawberry leaves with asymptomatic latent infection by Colletotrichum acutatum became visible using SDEI. Salmon-pink conidial masses were produced in the acervuli on the treated leaves 5 days after incubation at 28°C. In the case of Dendrophoma obscurans, pycnidia with amber conidial masses formed 5 days after incubation at 28°C. The pycnidia were observed mainly on the ribs, and conidial masses exuded from the ostiole. These macroscopic conidial masses were similar to those of G. cingulata and C. acutatum. When water was dripped onto a lesion caused by D. obscurans, the pycnidia exuded white filamentous conidial masses, making the distinction of D. obscurans from G. cingulata or C. acutatum. On petioles with latent infection by Fusarium oxysporum f. sp. fragariae, white aerial hyphae grew out from the vascular tissues on the cut surface 3 days after incubation at 28°C and were easily observed by eye or with a loupe. Thus, SDEI was also useful for diagnosing latent infection of strawberry plants by C. acutatum, D. obscurans, and F. oxysporum f. sp. fragariae.  相似文献   
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Dwarf Lulu cattle, the only Bos Taurus type of cattle in Nepal, are raised under severe environments in the mountainous zone of that country. In the present study, the body measurement traits, cytogenetic and molecular genetic characteristics of the Lulu cattle are investigated. Blood samples were collected from 31 animals in four villages (altitudes 2590–3550 m) in the southern part of Mustang. The Lulu cattle had a normal karyotype with 2n = 60, XY or XX. Only one male examined had a large submetacentric X‐chromosome and a small submetacentric taurine type Y‐chromosome. The mitochodrial DNA (mtDNA) genotypes were analyzed by PCR mediated restriction fragment length polymorphisms, displacement (D)‐loop region PCR mediated single strand conformation polymorphisms, and D‐loop region sequences. Many base substitutions were found in the D‐loop region, suggesting that the Lulu cattle originated from at least 10 maternal lines. Three types of mtDNA from these cattle were found, the Bos taurus type (n = 23), the Bos indicus type (n = 6), and the Bos grunniens type (n = 2). In the village at the lowest altitude, four of the five cows were of the Bos indicus type. These results indicated that mtDNA types of the Lulu cattle mostly belong to Bos taurus, but have been hybridized with Bos indicus cattle in lower‐elevation regions in their maternal lineage.  相似文献   
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MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has antiviral activity. MX has at least two isoforms, known as MX1 and MX2, in mammals. Moreover, bovine MX1 has been found to have alternative splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is temporarily produced from the conceptus before implantation and induces MX expression in the endometrium. However, the expression dynamics of MX after implantation are not clear. In the present study, we investigated the expression of MX1-a, MX1B and MX2 in the endometrium and placenta before and after implantation along with the expression of IFN-α, type I receptors (IFNAR1 and IFNAR2) and interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P). Although all the MX expressions were significantly higher in the IC and C at days 14–18, presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC. RT-PCR indicated IFNAR1, IFNAR2, IRF3 and IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the MX genes are affected by the type I IFN pathway during pregnancy and are involved in an immune response to protect the mother and fetus.  相似文献   
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Epidemiological and bacteriological survey of buffalo mastitis in Nepal   总被引:2,自引:0,他引:2  
A total of 355 Murrah cross buffaloes, consisting of 23 subclinical and 332 clinical mastitis cases brought to the Veterinary Teaching Hospital, Chitwan, Nepal from 2002 to 2005, were analyzed to determine the organisms involved, the seasonal occurrence of mastitis, and antibiotic susceptibility of mastitis pathogens. Coagulase negative Staphylococci (CNS) such as Staphylococcus albus and S. epidermidis were the predominant organisms associated with subclinical cases, and CNS and Coliforms in clinical cases. The maximum number (16%) of clinical cases of mastitis were observed in the month of July, when temperature and humidity are highest. The incidence of clinical mastitis was higher in animals during 1st calving and during the 1st month of parturition. Resistance to antibiotics was determined for 55, 23 and 149 isolates of Staphylococcus spp., Streptococcus spp. and Coliforms, respectively. In vitro drug sensitivity testing revealed that enrofloxacin had the highest average sensitivity (91%) for all types of bacteria. The effectiveness of other drugs detected were gentamicin (87%), tetracycline (83%) and chloramphenicol (82%). The antibiogram showed that both gentamicin and enrofloxacin are slowly becoming resistant. Mastitis pathogens have developed resistance to ampicillin and penicillin.  相似文献   
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Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is widely used as a flame retardant and is known to exhibit anti-androgenic effects in vitro and in vivo. To assess the reproductive toxicity potency of TDCIPP, we investigated the effects of 7 days of TDCIPP oral administration on epididymal sperm motion and concentration in adult male Wistar–Imamichi rats. Thirty-five days after the final administration, sperm parameters were evaluated by computer-assisted sperm analysis. Results showed that sperm swimming progression and vigor and sperm concentration in TDCIPP-treated rats were unexpectedly higher than those in control rats. TDCIPP did not significantly affect the percentage of motile sperms or sperm swimming pattern. These results contribute to the understanding of the biological effects of TDCIPP.  相似文献   
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Beneficial utilization of yuzu (Citrus junos) peel was investigated to improve the commercial value of cultured yellowtail fish. The antioxidant effects of grated yuzu peel from pomace (yuzu paste) on prevention of dark muscle discoloration during storage in sliced yellowtail fish were tested. Four diets were prepared, containing 0, 10, 50, and 100 g yuzu paste in a 1,450-g diet (wet basis). Fish were fed one of the four diets for 10 weeks. Growth performance was not significantly different among the dietary groups, but fish fed a diet containing 100-g yuzu paste showed the least average body weight and a significant increase in fecal amount and fat levels in the feces, which suggest low digestibility and low absorption. Dark muscle discoloration was significantly reduced in all yuzu dietary groups compared to the control group during storage at 4°C. The optimal supplementation of yuzu paste in the fish diet is very effective at maintaining fish flesh freshness as a finishing diet without causing additional phosphorus or nitrogen pollution of the sea and inhibiting fish growth. This study provides a new way to utilize waste yuzu peel, which also helps reduce waste from yuzu processing.  相似文献   
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