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991.
992.
SIMULATED NATURAL INFECTION OF CHICKENS WITH AUSTRALIAN LENTOGENIC NEWCASTLE DISEASE VIRUS AND SUBSEQUENT CHALLENGE WITH VIRULENT VIRUS 总被引:1,自引:0,他引:1
A. J. Turner M.V.Sc. Ph.D. R. P. Hanson Ph.D. J. Spalatin V.M.D. 《Australian veterinary journal》1976,52(11):524-528
A total of 291 eight-week-old chickens were exposed to chickens infected with either of two Australian lentogenic strains (V4 and AVL NDV-1) of Newcastle disease virus (NDV). At 3 weeks after exposure, all chickens exposed to V4 infected chickens had developed haemagglutination-inhibition (HI) antibody. All chickens exposed to AVL NDV-1 virus infected chickens had developed HI antibody 5 weeks later. This sudden late appearance of HI antibody, to titres higher than those observed with V4 chickens, was explained by V4 virus being introduced to the AVL NDV-1 group of chickens. When groups of these chickens were challenged with Roakin virus (mesogenic NDV) at 3 weeks and Fontana 1083 virus (viscerotropic velogenic NDV) and Texas GB virus (neutrotropic NDV) at 3, 5, 10 and 21 weeks only three chickens developed clinical illness one of which died. These chickens were one AVL NDV-1 chicken contact challenged with Fontana 1083 virus at 3 weeks, one V4 chicken oronasally challenged with Texas GB virus at 5 weeks and one V4 chicken challenged oronasally with Fontana 1083 virus at 10 weeks. Susceptible non-vaccinated chickens died soon after challenge. Challenge by oronasal infection with 10(7.0) ELD50 of virus or contact with susceptible infected chickens enabled virulent virus to be isolated from most chickens and was accompanied by a large anamnestic increase in serum HI antibody. 相似文献
993.
Indicators of success for smart law enforcement in protected areas: A case study for Russian Amur tiger (Panthera tigris altaica) reserves 下载免费PDF全文
Michiel H. H. HÖTTE Igor A. KOLODIN Sergei L. BEREZNUK Jonathan C. SLAGHT Linda L. KERLEY Svetlana V. SOUTYRINA Galina P. SALKINA Olga Y. ZAUMYSLOVA Emma J. STOKES Dale G. MIQUELLE 《Integrative zoology》2016,11(1):2-15
Although considerable conservation resources have been committed to develop and use law enforcement monitoring and management tools such as SMART, measures of success are ill‐defined and, to date, few reports detail results post‐implementation. Here, we present 4 case studies from protected areas with Amur tigers (Panthera tigris altaica) in Russia, in which indicators of success were defined and evaluated at each. The ultimate goal was an increase in tiger numbers to 1 individual/100 km2 at each site. We predicted that improvements in law enforcement effectiveness would be followed by increases in prey numbers and, subsequently, tiger numbers. We used short‐term and long‐term indicators of success, including: (i) patrol team effort and effectiveness; (ii) catch per unit effort indicators (to measure reductions in threats); and (iii) changes in target species numbers. In addition to implementing a monitoring system, we focused on improving law enforcement management using an adaptive management process. Over 4 years, we noted clear increases in patrol effort and a partial reduction in threats. Although we did not detect clear trends in ungulate numbers, tiger populations remained stable or increased, suggesting that poaching of tigers may be more limiting than prey depletion. Increased effectiveness is needed before a clear reduction in threats can be noted, and more time is needed before detecting responses in target populations. Nonetheless, delineation of concrete goals and indicators of success provide a means of evaluating progress and weaknesses. Such monitoring should be a central component of law enforcement strategies for protected areas. 相似文献
994.
995.
The effects of passive immunization with immunoglobulin Y (IgY) on the pathogenesis of Marek's disease (MD) were examined in an experimental line of White Leghorn chickens highly susceptible to MD. Purified IgY with anti-MDV antibody activity, when injected into chicks, delayed the development of MDV viremia and lesions until 9 days postinoculation (PI) with Marek's disease virus (MDV). The blastogenic response of spleen cells to concanavallin-A was depressed at 6 days PI in the birds without passive immunization, whereas it was not totally depressed until 17 days in birds passively immunized with IgY anti-MDV antibody. 相似文献
996.
V Kati L Scarabel D Thiery‐Lanfranchi V Kioleoglou S Liberopoulou C Dlye 《Weed Research》2019,59(5):367-376
The issue of cross‐ or multiple resistance to acetolactate synthase (ALS) inhibitors and the auxinic herbicide 2,4‐D was investigated in Papaver rhoeas L., a common and troublesome weed in winter cereals, in a broad‐scale study across four European countries. A combination of herbicide sensitivity bioassays and molecular assays targeting mutations involved in resistance was conducted on 27 populations of P. rhoeas originating from Greece (9), Italy (5), France (10) and Spain (3). Plants resistant to the field rate of 2,4‐D were observed in 25 of the 27 populations assayed, in frequencies ranging from 5% to 85%. Plants resistant to ALS‐inhibiting herbicides (sulfonylureas) were present in 24 of the 27 populations, in frequencies ranging from 4% to 100%. Plants resistant to 2,4‐D co‐occurred with plants resistant to sulfonylureas in 23 populations. In four of these, the probability of presence of plants with cross‐ or multiple resistance to 2,4‐D and sulfonylureas was higher than 0.5. ALS genotyping of plants from the field populations or of their progenies, identified ALS alleles carrying a mutation at codon Pro197 or Trp574 in 2,4‐D‐sensitive and in 2,4‐D‐resistant plants. The latter case confirmed multiple resistance to 2,4‐D and ALS inhibitors at the level of individual plants in all four countries investigated. This study is the first to identify individual plants with multiple resistance in P. rhoeas, an attribute rarely assessed in other weed species, but one with significant implications in designing chemical control strategies. 相似文献
997.
Wakita Y Kawano J Shimizu A Hajek V Tomisaka E Yasuda R Matsuo E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(7):603-605
The development of a PCR assay based on the 16S ribosomal RNA gene (rDNA) sequence was carried out for the identification of Staphylococcus intermedius. Sixty-six strains of S. intermedius, 70 of Staphylococcus aureus and 2 of Staphylococcus hyicus were examined for the assay. The 16S rDNA, of which the PCR target fragment makes up 901 bp corresponding to the sequence data of the gene, was detected in all strains of S. intermedius, but it was not detected in any strains of either S. aureus or S. hyicus. These results suggest that the PCR allows a simple and precise identification of S. intermedius. 相似文献
998.
Al. Polizu Stefania Floru Al. V. Alexandri 《Plant foods for human nutrition (Dordrecht, Netherlands)》1968,15(3):299-307
Résumé On présente des données sur la persistence du DDT sur tomates, poivrons, et aubergines en plein champ, et sur tomates en serre, à la suite de l'application des traitements par concentrés émulsifiables. Dans le cas des tomates on a constaté que le dépôt résiduel est audessous de 1 ppm apres un intervalle de 11 jours depuis l'application du traitement en champ. En serre, et pour la même quantité de substance toxique, la persistence se maintient jusqu'à 36 jours.Le dépôt initial sur aubergines est plus élevé que dans le cas des tomates, atteignant jusqu'à 1 ppm. après environ 22 à 29 jours. Chez les poivrons, le résidu initial est très grand par rapport aux deux premières légumes et atteint 19 ppm. 22 Jours après le traitement celui-ci varie entre 0,8–1,3 ppm.Ensuite, on a étudié la dynamique de la répartition dans le temps de la substance toxique par unité de surface. Les résultats obtenus démontrent l'uniformité des traitements; la diminution de la quantité de substance toxique dans le temps est due autant au facteur croissance qu'aux conditions de climat.
avec 4 figs. 相似文献
Summary The paper deals with data on the persistence of DDT on tomatoes, sweet peppers and eggplants in the field, and on tomatoes in the greenhouse, following the application of emulsions. It is shown that in tomatoes, residual deposits are below 1 ppm 11 days after treatments in the field. In the greenhouse, the persistence is long-lasting, attaining up to 36 days when the same amount of toxicant is applied.In eggplants, the initial deposit is higher than in tomatoes attaining about 1 ppm after 22–29 days. In sweet peppers, the initial amount of residue is very large as compared to the first two vegetables and attains 19 ppm; 22 days after the treatement it ranges between 0.8–1.3 ppm.Besides, the dynamics of toxicant distribution with time, per area unit was studied. The data obtained demonstrate the uniformity of the treatments, and that the diminution of the amount of toxicant with time is due to both the growth factor and the climate conditions.
Zusammenfassung In diesem Beitrag werden Daten betreffs der Karenzzeit der DDT-Rückstände auf Tomaten, Paprika und Eierfrüchten nach Behandlung des Feldbestandes und auf Tomaten, die im Treibhaus mit DDT-Emulsionen behandelt wurden, wiedergegeben. Aus unseren Untersuchungen geht hervor, daß der Rückstandswert auf Tomaten 11 Tage nach der Behandlung des Feldbestandes weniger als 1 ppm beträgt. Im Treibhaus hingegen erstreckt sich die Karenzzeit (Verweildauer) bis auf 36 Tage unter Anwendung derselben Wirkstoffmenge.Auf den Eierfrüchten ist der anfängliche Rückstandswert größer als auf den Tomaten und erreicht nach ungefähr 22–29 Tagen Werte unter 1 ppm. Im Falle der Paprikaschoten sind die Rückstandswerte anfangs sehr hoch im Gegensatz zu den vorher genannten Gemüsesorten und zwar erreichen sie 19 ppm. Nach 22 Tagen verzeichnen wir hier Werte von 0,8–1,3 ppm.Anschließend verfolgten wir die Dynamik der Wirkstoffverbreitung im Verhältnis der Zeit zur Oberflächeneinheit.Die erzielten Ergebnisse deuten sowohl auf eine uniform durchgeführte Behandlungsweise hin als auch auf die Tatsache, daß der zeitliche Rückgang der Rückstandsmenge von Wachstum und Klimabedingungen abhängig ist.
avec 4 figs. 相似文献
999.
1000.
Castillo VA Gómez NV Lalia JC Cabrera Blatter MF García JD 《Research in veterinary science》2008,85(1):26-34
The treatment of pituitary-dependent hyperadrenocorticism (PDH) in dogs has for a long time been focused on inhibiting the adrenal gland using drugs such as o-p'-DDD, Ketoconazole and Trilostane, without attacking the primary cause: the corticotrophinoma. Corticotroph cells can express the D2 dopaminergic receptor; therefore cabergoline (Cbg) could be effective as a treatment. Follow-up over 4 years was carried out in 40 dogs with PDH that were treated with Cbg (0.07 mg/kg/week. Out of the 40 dogs, 17 responded to Cbg (42.5%). A year after the treatment, there was a significant decrease in ACTH (p<0.0001), alpha-MSH (p<0.01), urinary cortisol/creatinine ratio (p<0.001), and of the tumor size (p<0.0001) evaluated by nuclear magnetic resonance. Dogs responding to Cbg lived significantly longer (p<0.001) than those in the control group. To conclude, Cbg is useful in 42.5% of dogs with PDH, justifying its use as a treatment. 相似文献