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51.
Carbendazim, iprodione, prochloraz-Mn, thiabendazole and thiophanate-methyl were tested in vitro and in vivo for their effect on Mycogone perniciosa, the mycoparasite that causes wet bubble disease of white button mushroom. In vitro experiments showed that prochloraz-Mn (ED50 = 0.006–0.064 μg ml−1) and carbendazim (ED50 = 0.031–0.097 μg ml−1) were the most effective fungicides for inhibiting the mycelial growth of M. perniciosa, while iprodione (ED50 = 1.90–3.80 μg ml−1) was the least effective. The resistance factors calculated for the five fungicides were between 1.4 and 2. The results obtained suggest that there is very little risk that M. perniciosa will develop resistance to the fungicides assayed. The in vivo efficacy of fungicides for control of wet bubble was studied in two mushroom cropping experiments, which were artificially infected with two doses of M. perniciosa, 106 and 107 spores m−2, respectively. There was, in the low dose inoculum experiment, a very high degree of effectiveness (96.5–100.0%) with all the fungicides assayed. However, iprodione performed poorly (20.5–24.4%) compared with the other fungicides (88.7–100.0%) in the high concentration inoculum experiment. The most effective treatments for controlling wet bubble did not improve the biological efficiency of Agaricus bisporus.  相似文献   
52.
Equine coital exanthema (ECE) is an acute, venereal disease caused by equid herpesvirus 3 (EHV-3), characterized by the formation of papules, vesicles, pustules, and ulcers on the vaginal and vestibular mucosa as well as on the skin of the penis, prepuce, and perineal region of mares and stallions. The present work describes an outbreak of ECE characterized by typical lesions around the anus and on the perineal skin, discomfort, and anorectal lymphadenopathy, which occurred in a large number of donor and recipient mares at an embryo transfer center in Argentina. We found that the horses' movement pattern, the environmental conditions, and the management procedures could have favored the introduction and/or reactivation from latency and spread of EHV-3. Although this is the first report of an outbreak of ECE in an embryo transfer facility, it reinforces the need to introduce additional hygienic and preventive measures to avoid EHV-3 spread and future ECE outbreaks.  相似文献   
53.
54.
Hatchery vaccination protocols in day-old chicks are designed to provide early priming and protection against several poultry diseases including, but not limited to, Marek's disease (MD), infectious bursal disease (IBD), and Newcastle disease (ND). The constraint of concomitant administration of live MD and IBD vaccines plus ND inactivated oil-adjuvanted vaccines (IOAVs) requires improvements in vaccine technology. Single-needle concomitant subcutaneous (SC) application of IBD/MDV and killed NDV vaccine and the use of viral vectors for expression of immunogenic proteins are a current trend in the industry. The objective of this work was to assess the compatibility of a turkey herpesvirus (HVT)-infectious bursal disease (vHVT-IBD) vector vaccine applied simultaneously with IOAV and to evaluate the consequences for vaccine intake, the need for additional immunizations with the respective vaccines, and protection. Five separate trials were performed using double- and/or single-needle injectors. The levels and persistence of vaccine intake, serologic response, vHVT-IBD virus combination with the MD Rispens strain, and/or live NDV vaccination were also assessed. Histopathology and PCR at injection sites showed adequate vaccine intake detected up to 44 days postvaccination. Serologic evidence of vaccine priming was observed, and all vaccinated groups differed (P < 0.05) from the control at different time points. MD, NDV, and IBD protection results after concomitant double-shot single-needle vaccination were near 85%, 95%, and 100%, respectively. Taken together the results indicate no deleterious effects on the efficacy of the vHVT-IBD vaccine monitored by vaccine intake, serologic and challenge results, and combinations after concomitant live/killed vaccination, suggesting the suitability of its use in hatchery vaccination. All types of injectors used as well as injection techniques, vaccines injected separately or together, gave the same results.  相似文献   
55.
Recombinant adenoviral vectors have emerged as an attractive system for veterinary vaccines development. However, for poultry vaccination a very important criterion for an ideal vaccine is its low cost. The objective of this study was to test the ability of chicken CD154 to enhance the immunogenicity of an adenoviral vector-based vaccine against avian influenza virus in order to reduce the amount of antigen required to induce an effective immune response in avian. Chickens were vaccinated with three different doses of adenoviral vectors encoding either HA (AdHA), or HA fused to extracellular domain chicken's CD154 (AdHACD). Hemagglutination inhibition (HI) assay and relative quantification of IFN-γ showed that the adenoviral vector encoding for the chimeric antigen is able to elicit an improved humoral and cellular immune response, which demonstrated that CD154 can be used as a molecular adjuvant allowing to reduce in about 50-fold the amount of adenoviral vector vaccine required to induce an effective immune response.  相似文献   
56.
The pharmacokinetics properties of marbofloxacin were studied in adult Eurassian Griffon vulture after single-dose intravenous (IV) administration of 2 mg/kg. Drug concentration in plasma was determined by high-performance liquid chromatography and the data obtained were subjected to compartmental and non-compartmental kinetic analysis. Marbofloxacin presented a volume of distribution at steady-state (Vdss) of 1.51 ± 0.22 L and total plasma clearance (Cl) of 0.109 ± 0.023 L/h kg. The permanence of this drug was long in vultures (T1/2λ = 12.51 ± 2.52 h; MRT = 13.54 ± 2.29 h). The optimal dose of marbofloxacin estimated is 2.73 mg/kg per day for the treatment of infections in vultures with MIC90 = 0.2 μg/mL.  相似文献   
57.
In order to describe the normal bacterial flora in vaginas of Criollo Limonero cows, 51 healthy multiparous cows, at least 90-day postpartum, were selected. Duplicated swabs (N = 102) were taken from the vaginal fornix of cows to perform aerobic and anaerobic cultures as well as conventional biochemical tests. Out of 102 swabs, bacterial growth was obtained in 55 (53.9%) while the remaining 47 (46.1%) did not exhibited any bacterial growth. Of the 55 bacterial growths, 23 (41.8%) were aerobic whereas 32 (58.1%) were anaerobic. Likewise, 29 (52.72%) of bacterial growths were pure and 26 (47.27%) were mixed. Under both aerobic and anaerobic conditions, Gram positive bacteria were predominant (81.82% and 73.08%, respectively) over Gram negative bacteria (18.18% and 26.92%, respectively). Isolated bacteria were Arcanobacterium pyogenes (22.92%), Staphylococcus aureus (15.63%), Staphylococcus coagulase negative (17.71%), Erysipelothrix rhusiopathiae (6.25%), Bacteroides spp. (13.54%), and Peptostreptococcus spp. (7.29%). In conclusion, normal vaginal bacterial flora of Criollo Limonero cows was predominantly Gram positive and included A. pyogenes, S. aureus, coagulase negative Staphylococcus, E. rhusiopathiae, Bacteroides spp., and Peptostreptococcus spp. In Criollo Limonero cattle, adaptive aspects such as development of humoral and physical mechanisms for defense, and bacterial adaptation to host deserve research attention.  相似文献   
58.
Veterinary inspection in slaughterhouses allows for the detection of macroscopic lesions reminiscent of bovine tuberculosis, but the presence of Mycobacterium bovis must be confirmed by laboratory methods. This study aimed at comparing the performances of the standard diagnostic tools used to identify M. bovis in tissue specimens sampled from suspicious animals. During a two years period, 1390 cattle were inspected at the Machachi abattoir in the Mejia canton - Ecuador. A total of 33 animals with granulomatous lesions were detected, representing 2.33% (16/687) and 2.42% (17/703) animals examined in 2007 and 2008, respectively. Ninety-four tissue specimens were sampled and screened for the presence of mycobacteria. Acid-fast bacilli were identified in one third of the suspicious cattle (11/33) and suggestive microscopic lesions in 27.3% (9/33) of the samples examined by direct microscopy and histopathology, respectively. Culturing on Stonebrink medium and 16S-rRNA-based polymerase chain reaction (PCR) yielded 36.4% (12/33) and 27.3% (9/33) of positives, respectively. Compared to culture, other diagnostic procedures displayed a lower sensitivity, with 56.5% for PCR, and 43.5% for direct microscopy and histopathology; however, the specificity was higher (94.4% for PCR and microscopy, and 97.2% for histopathology). We conclude that reliable post-mortem laboratory testing either requires the combination of a set of available diagnostic tools or necessitates the development of improved new-generation tools with better sensitivity and specificity characteristics.  相似文献   
59.
Tropical Animal Health and Production - Currently for the reduction of methane (CH4) emissions are using fodder rich in condensed tannins, however, not yet known exactly how they act in the rumen...  相似文献   
60.
The amount and composition of crop residues added to soil in agroecosystems can influence decomposition processes and soil organic matter levels. This study aimed to evaluate residues (quantity and quality) of different corn cultivars commonly used in Brazilian cropping systems. The experiment was conducted for two seasons (2005/2006 and 2006/2007) in Rolândia, Paraná State, Brazil. Ten corn cultivars that represent five degrees of breeding development (i.e., landrace, commercial variety, double cross, triple cross, and single cross hybrids) were evaluated. At harvest, carbon (C) and nitrogen (N) of non-yield residue and grain were determined. Except for grain C, other measures (grain N concentration, residue C and N concentration, and C:N ratio) varied among cultivars. In general, the hybrids had higher residue C and lower residue N concentrations than the landraces and commercial varieties. Findings suggest that breeding selection may have altered residue production and composition, which may influence soil C dynamics.  相似文献   
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