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排序方式: 共有204条查询结果,搜索用时 718 毫秒
41.
Blight LK Ainley DG Ackley SF Ballard G Ballerini T Brownell RL Cheng CH Chiantore M Costa D Coulter MC Dayton P Devries AL Dunbar R Earle S Eastman JT Emslie SD Evans CW Garrott RA Kim S Kooyman G Lescroël A Lizotte M Massaro M Olmastroni S Ponganis PJ Russell J Siniff DB Smith WO Stewart BS Stirling I Willis J Wilson P Woehler EJ 《Science (New York, N.Y.)》2010,330(6009):1316
42.
Canine atopic dermatitis is a multifaceted disease, whose clinical presentation may be affected by numerous factors, including the genetic background of the animal, the environment, the offending allergens and flare factors. In particular, breed-associated differences have often been mentioned but never defined precisely. Using a large data set of atopic dogs, we document in this study the clinical presentation of nine often-affected breeds and demonstrate the existence of substantial differences between the clinical phenotype of each breed and the whole population. Some of the differences may be due to genetic differences while others are most likely to be associated with variations in environmental factors. 相似文献
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44.
Marcin Przybyo Marcus Clauss Sylvia Ortmann Zygmunt M. Kowalski Pawe Grka 《Journal of animal physiology and animal nutrition》2019,103(6):1684-1693
The aim of the study was to determine the effect of fructose supplementation in the diet on feed intake, nutrient digestibility and digesta retention time in Reeves's muntjac (Muntiacus reevesi), a browsing cervid. In Experiment 1, six adult males of Reeves's muntjac were used in a replicated 3 × 3 Latin square design and fed a diet consisting of dehydrated chopped lucerne (ad libitum), high‐fibre pellet (120 g/day) and wheat bran (30 g/day) without (F0) or with addition of 12 and 24 g fructose/day (F12 and F24, respectively). In Experiment 2, the same six adult muntjacs were used in crossover design and fed F0 or F12. Doses of supplemental fructose were set to increase intake of water‐soluble carbohydrates (WSC; ≈40 g/day; ≈8% of WSC in consumed dry matter [DM]) by 25 and 50% relative to F0. Feed intake was controlled daily (Experiment 1 and 2) and total tract digestibility and digesta retention time were determined (Experiment 2). In Experiment 1, DM intake of chopped dehydrated lucerne decreased with fructose supplementation (F0 vs. F12 and F24; p = .01) but was not different between F12 and F24 (p = .76). Total DM intake was also not different between treatments (p ≥ .13). In Experiment 2, DM intake of lucerne, total DM intake and nutrient digestibility was not affected by fructose supplementation (p ≥ .17), but mean retention time of long particles in the whole GIT tended to be longer for F12 compared to F0 (p = .09). Under conditions of the current study, additional fructose intake (resulting in a range of WSC content in consumed DM from 8.6% to 13%) had only minor impact on feed intake and investigated functions of the gastrointestinal tract of Reeves's muntjac. 相似文献
45.
Dinka Grubišić Ljerka Oštrec Tanja Gotlin Čuljak Sylvia Blümel 《Journal of pest science》2007,80(1):21-27
Potato cyst nematodes (PCN) Globodera rostochiensis (Wollenweber, 1923) Behrens, 1975 and Globodera pallida (Stone, 1973) Behrens, 1975 are the most troublesome pests of potatoes worldwide. Since 1968 there have been no investigations
of the presence of PCN in ware potato lands in Croatia although these pests were recognised as an A1 plant-health quarantine
species. After the first discovery of G. rostochiensis in the locality of Belica (Medjimurska County) in 2001, intensive monitoring of the distribution of PCN in Croatia started.
In 2001 G. rostochiensis was detected in 55% of soil samples taken in ware potato lands. In 2002 G. rostochiensis was detected in 4.1% of soil samples and in 0.08% of soil samples in mixed populations with G. pallida. The pathotype Ro1 was found in all tested populations and Ro1 and Pa 2/3 were detected in populations from localities Vidovec,
Ivanovec and Sivice. In 2003 G. rostochiensis was detected in 1.03% of soil samples, and also in 12.8% of soil samples collected in 2004. In 2003 cysts of G. rostochiensis were detected in several seed potato fields. These results indicate the urgent need for the application of further control
measures to determine the presence and distribution of PCN in ware and seed potato lands in Croatia, in order to prevent the
spread of PCN to non-infested areas. Integrated management strategies, neglected until 2001, have now been implemented and
will prevent the build-up of infestation and replace the previous practices of monoculture, the use of short rotations and
growing susceptible cultivars. 相似文献
46.
Sadeghi A Broeders S De Greve H Hernalsteens JP Peumans WJ Van Damme EJ Smagghe G 《Pest management science》2007,63(12):1215-1223
BACKGROUND: To check for correlation between the insecticidal properties and the specificity of lectins, a comparative study was made of the insecticidal activities of two garlic lectins with different biological activities.RESULTS: The insecticidal activity of the garlic (Allium sativum L.) leaf lectin ASAL and bulb lectin ASAII towards the tobacco aphid Myzus nicotianae Blackman was studied using bioassays with transgenic tobacco (Nicotiana tabacum L. cv. Wisconsin 38). Bioassays were started with newborn nymphs of the tobacco aphid. Although during the first 7-8 days when nymphs developed to adults there were no apparent effects, part of the nymphal population was found to develop into winged (alate) forms. Later it became clear that transgenic plants expressing ASAL and ASAII had a significant effect on the reproduction capacity of the resulting adults, with a reduction of up to 40%. Different life table parameters such as prereproductive time, intrinsic rate of natural increase, generation time and doubling time were significantly affected (P < 0.05) in aphids grown on transgenic plant material expressing ASAL and ASAII.CONCLUSION: Bioassays with tobacco plants expressing ASAL and ASAII demonstrated a significant impact on the population growth of M. nicotianae. Therefore, both lectins can be considered as valuable candidate aphid control agents. 相似文献
47.
Double-stranded RNA and type I interferon-like activity induce an antiviral state in vertebrate cells and in several fish cell lines by increasing the expression of proteins that inhibit virus replication. We compared the protection induced by the polyinosinic:polycytidylic acid (poly I:C) or poly I:C plus transfection agents against the infectious pancreatic necrosis virus (IPNV) and the infectious hematopoietic necrosis virus (IHNV) in BF-2 cells, with that induced in RTG-2, CHSE-214, or SAF cells. In addition, we examined the reduction in the infective titers of these viruses and the correlation with Mx protein expression as IFN marker. Furthermore, the suitability of BF-2 cells for the evaluation and optimization of immune responses in an IPNV-IHNV co-infection was assessed. The results demonstrated strong anti-IPNV and anti-IHNV activity (around 90% of infected cells surviving) in BF-2 cells transfected with poly I:C, in which a loss of 1log(10) or 3log(10) of the IPNV or IHNV infective titers, respectively, was observed. No antiviral activity was evident in the cells incubated with poly I:C alone. The protection recorded in the co-infection experiments was comparable with those of the single infections. The SAF cell line exhibited the lowest antiviral capacity (45%), which was also increased after transfection with poly I:C. In addition, medium from transfected BF-2 provided protection against IPNV (1log(10) loss of infective titer) and IHNV (2log(10) loss of infective titer) in new monolayers, indicating that these cells secreted the factors that induce antiviral activity. A correlation between antiviral activity and Mx protein expression was observed in all the cells. These results indicate that poly I:C transfection could improve IFN-like production in these cell lines. However, the antiviral effectiveness of poly I:C differed between cell lines. On the basis of our findings, we conclude that the BF-2 cell line is a useful model in which to study the role of IFN-induced cytokines in resistance against single or double infections with salmonid fish viruses. 相似文献
48.
49.
Koslowsky S Staubach C Kramer M Wieler LH 《Berliner und Münchener tier?rztliche Wochenschrift》2004,117(5-6):214-225
Using a geographic information system (GIS), by analysis of the relationship between the spatial distribution of cattle density and the risk factors temperature, altitude and rainfall, we defined geographical habitats enabling optimal development and competence of Culicoides spp. to transmit Bluetongue-Virus (BTV): Risk zones (low, high, highest risk) were identified mainly in Baden-Württemberg, Hessen and Rheinland-Pfalz if persistently infected ruminants are imported into these zones in summer (June to August mainly), based on the current climatic conditions, BTD outbreaks are considered a real possibility. Overwintering of the virus seems unlikely. However, global warming will lead to a steady increase of the size of the risk zones. In addition, the possibility of primary outbreaks increases. The reason for this is not only the expected northern shift of Culicoides imicola, but in addition an increasing vector competence of domestic Culicoides species. We therefore recommend the storage of vaccines as well as conducting ecological studies analysing the presence of Culicoides vectors. Using the data from these studies, it will be possible to produce updated quantitative risk assessment via GIS. 相似文献
50.
Five hundred sixty-nine Salmonella were isolated out of 4745 samples from poultry products, poultry, and poultry environment in 1999 and 2000 from the Pacific northwest. These Salmonella were identified to their exact source, and some were serogrouped, serotyped, phage typed, and tested for antibiotic sensitivity. Food product samples tested included rinse water of spent hens and broilers and chicken ground meat. Poultry environment samples were hatchery fluff from the hatcheries where eggs of grandparent broiler breeders or parent broiler breeder eggs were hatched and drag swabs from poultry houses. Diagnostic samples were of liver or yolk sac contents collected at necropsy from the young chicks received in the laboratory. Of these samples tested, 569 were Salmonella positive (11.99%). Ninety-two Salmonella were serogrouped with polyvalent somatic antisera A-I and the polymerase chain reaction. Somatic serogroups B and C comprised 95.25% of all the Salmonella. Out of a total of 569 positive samples, 97 isolates of Salmonella were serotyped. A total of 16 serotypes and an unnamed Salmonella belonging to serogroup C1 were identified. The Salmonella serotypes were heidelberg (25.77%); kentucky (21.64%); montevideo (11.34%); hadar and enteritidis (5.15% each); infantis, typhimurium, ohio, and thompson (4.12% each); mbandaka and cerro (3.09% each); senftenberg (2.06%); berta, istanbul, indiana, and saintpaul (1.03% each); and an unnamed monomorphic Salmonella (2.06%). Ninety-two Salmonella were tested for drug sensitivity with nine different antimicrobials. All of the 92 Salmonella were resistant to erythromycin, lincomycin, and penicillin except one sample (S. berta), which was moderately sensitive to penicillin. All of the tested Salmonella were susceptible to sarafloxacin and ceftiofur. The percentages of Salmonella susceptible to sulfamethoxazole-trimethoprim, gentamicin, triple sulfa, and tetracycline were 97.83%, 92.39%, 86.96%, and 82.61%, respectively. 相似文献