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51.
Eighty stone fruit nurseries located in different regions of Poland were examined for the presence of crown gall affected plants. The disease was observed in 39 nurseries, and galls were sampled for bacterial isolation. Out of 1213 isolates, 409 were pre‐identified as Agrobacterium/Rhizobium spp. with 23S rDNA‐based multiplex PCR, and out of these, 315 were pathogenic when tested on sunflowers. Sequence analysis of three housekeeping genes (fusA, recA, rpoD) revealed that 366 strains belonged to Rhizobium rhizogenes, 23 to Agrobacterium tumefaciens species complex, and the rest of the strains were allocated to new phylogenetic lineages. Of these, the most numerous was the lineage allocated in the Pararhizobium genus. Positive results obtained from pathogenicity tests were generally in agreement with results obtained by PCR with primers complementary to T‐DNA except for two strains, which were positive for PCR but negative for the pathogenicity test. All detected Ti plasmids were nopaline‐type. Independent of their pathogenicity, 59% of tested strains were not sensitive to agrocin 84 in in vitro tests. Analysis of biochemical and physiological features distinguished 50 groups with different phenotypic profiles, but the tested traits were not consistent for strains classified to one taxon. This finding shows limited value of biochemical tests in identification procedures. The bacteria causing tumours were heterogeneous and strains classified to different taxa were found even in a single tumour.  相似文献   
52.
53.
Forty-two kiwifruit orchards from Rize and Samsun provinces (Black Sea region, Turkey) exhibiting symptoms of root rot disease were examined between 2009 and 2010. Twenty-four fungal isolates recovered from affected roots were included in this study. Morphological characteristics of all isolates were recorded on potato dextrose agar, malt extract agar and Spezieller Nährstoffarmer agar. The effect of temperature on radial colony growth was also evaluated at 5, 10, 15, 20, 25, 30, and 35 °C. Histone H3 gene (HIS) was amplified with primers CYLH3F and CYLH3R and the amplified fragments were sequenced. The HIS phylogeny grouped all the isolates into six well-supported clades which were in agreement with phenotypical characteristics. Isolates were identified as “Cylindrocarponpauciseptatum, Cylindrocladiella parva, Ilyonectria liriodendri, I. torresensis, I. robusta and I. europaea, I. liriodendri being the most frequent species. All of them are reported for the first time on kiwifruit in Turkey, with the exception of I. liriodendri. Pathogenicity tests with selected isolates showed that 10 out of 11 isolates tested were able to induce typical root rot disease symptoms, affecting plant development and leading to the death of some plants. This study shows the high diversity of root rot pathogens found in kiwifruit trees in the Black Sea region of Turkey, being the first step towards a better understanding and management of the disease in local conditions.  相似文献   
54.
BackgroundThe predominant infectious bronchitis virus (IBV) strains detected in chickens in Malaysia are the Malaysian variant (MV) and QX-like, which are associated with respiratory distress, nephropathy, and high mortality. On the other hand, the antigenic relatedness and efficacy of IBV vaccines against these 2 field IBV strains are not well characterized.ObjectivesThis study aimed to determine the antigen relatedness and efficacy of different IB vaccine strains against a challenge with MV and QX-like strains.MethodsThe antigen relatedness and the ability of different IB vaccine strains in conferring protection against MV and QX-like were assessed based on the clinical signs, macroscopic lesions, and ciliary activity.ResultsThe MV strain IBS037A/2014 showed minor antigenic subtype differences with the vaccine virus Mass H120 and 4/91 strains but showed major antigenic subtype differences with the K2 strain. The Malaysian QX-like strain IBS130/2015 showed major antigenic subtype differences with the MV strain IBS037A/2014 and the vaccine strains except for K2. Chickens vaccinated once with Mass (H120) or with non-Mass (4/91 and K2) developed antibody responses with the highest antibody titer detected in the groups vaccinated with H120 and 4/91. The mean ciliary activities of the vaccinated chickens were between 56 to 59% and 48 to 52% in chickens challenged with IBS037A/2014 and IBS130/2015, respectively. The vaccinated and challenged birds showed mild to severe lesions in the lungs and kidneys.ConclusionsDespite the minor antigenic subtype differences, a single inoculation with Mass or non-Mass vaccines could not protect against the MV IBS037A/2014 and QX-like IBS130/2015.  相似文献   
55.

The aim of this study was to determine the occurrence of on-farm risk factors and health effects associated with contamination of dairy feeds with aflatoxins (AFs), zearalenone (ZEN), trichothecenes (T-2), deoxynivalenol (DON), and fumonisins (FB) in Jordan. A pre-tested and validated questionnaire was used to determine on-farm practices and health effects associated with high levels of mycotoxins. A total of 88 feed samples were collected from the 37 farms participating in the study and analyzed using commercially available ELISA kits. The mean total AF concentration exceeded the European Union (EU) limit in alfalfa (4%) and total mixed ration (TMR) (3%) samples. Similarly, levels exceeding EU limits were observed for T-2 in alfalfa (29%), TMR (30%), and corn silage (4%). The average concentrations of ZEN and FB were 300 ppb and 11,638 ppb, respectively, which were below the EU maximum limits in all feed samples examined. Intensive management system (OR?=?7.70), imported feed (OR?=?3.40), feed storage on the farm for more than 1-month duration (OR?=?7.90), and not using antitoxins (OR?=?2.30) were significantly (P?<?0.05) associated with high levels of mycotoxins in feed samples. A significant correlation (P?<?0.05) was evident between the presence of mycotoxins in dairy feed and feed refusal (R?=?0.70), low milk production (R?=?0.50), diarrhea problems (R?=?0.60), infertility (R?=?0.50), and repeated breeder problems (R?=?0.80). Results show that mycotoxin contamination in dairy feeds is a problem in Jordan, and appropriate measures need to be undertaken to reduce risks to human and animal health and improve production.

  相似文献   
56.
The objectives of this study were to determine the pharmacokinetics of toltrazuril and its metabolites in pregnant and nonpregnant ewes following a single oral dose and to determine the plasma concentrations of these compounds in milk, allantoic fluid, and newborn plasma. Eighteen healthy ewes were randomly divided into three groups (n = 6 each): pregnant ewes at 12–13 weeks of gestation (group A), nonpregnant ewes (group B), and pregnant ewes at 1–2 weeks before expected lambing date (group C). Ewes in all groups received a single oral dose of toltrazuril at 20 mg/kg body weight. In groups A and B, blood samples were collected at 1, 3, 5, 7, 9, 12, 15, 18 hr, every 6 hr to day 3, every 12 hr to day 7 and thereafter every 24 hr to day 14 post-toltrazuril administration. In group C, parturition was induced 24–36 hr after toltrazuril administration then milk, allantoic fluid, and newborn plasma samples were collected immediately after birth. Drug metabolites were assayed using ultra high-performance liquid chromatography–ultraviolet detection method (UHPLC-UV). The maximum concentration (Cmax), area under the plasma concentration-time curve (AUC0–t), AUC to 24 and 48 hr (AUC0–24), and (AUC0–48) were significantly higher in pregnant ewes. Longer apparent half-life (T1/2), significantly higher apparent volume of distribution (Vd/F) and total clearance (Cl/F) were observed in nonpregnant ewes. The time to maximum plasma concentration (Tmax), mean residence time (MRT) and elimination rate constant (Kel) were similar in both groups. The AUC0–24 and AUC0–48 were significantly higher in nonpregnant ewes. The AUC0–t was significantly higher in pregnant ones. The ratio of plasma toltrazuril concentrations in ewes and toltrazuril concentrations in newborn lambs' plasma, allantoic fluid, and milk were 68%, 2.3%, and 5.3%, respectively. Results of this study showed that toltrazuril is well absorbed after a single oral dose in ewes with widespread distribution in different body tissues.  相似文献   
57.
The objective of the present study was to model in 3D the detailed morphometric features of the thoracic and pelvic limb bones of the gazelle (Gazella subgutturosa), whose natural habitat is only in the Sanliurfa province, by using multidetector computerized tomography (MDCT) images. Materials from 14 (7 male and 7 female) dead gazelles were collected from the Harran University Veterinary Medicine Faculty clinics during or after treatment. MDCT images of the gazelles were taken and saved as DICOM (Digital Imaging and Communications in Medicine) files. MIMICS 20.1 software was used to generate a 3D reconstruction of the data, and morphological and morphometrical evaluation was performed. In respect of morphological features, the combined metacarpus (Mc) III and metacarpus Mc IV were the main weight-bearing metacarpal bone, while Mc II and Mc V were rudimentary. On the femur, the lateral condyle was bigger than the medial condyle at the caudodistal end and the medial wing of the trochlea femoris was larger than the lateral. As with the thoracic limb, the combined metatarsus (Mt) III and metatarsus Mt IV were the main weight-bearing metacarpal bone and they displayed a synostosis structure. There was no secondary metatarsus in the gazelles’ pelvic limb. Based on digital measurements, the tibia was the longest bone of the gazelles’ skeletal system, and there was a statistically significant sexual dimorphism throughout the skeleton at the levels of p < .05, p < .01 and p < .001. As a result, the present study's findings are useful as reference data for further studies on anatomy, surgery and archaezoology, while also being useful for classifying species and for forensic sciences.  相似文献   
58.
In the daytime, the CO2 concentration in the air close to the water surface of a ponded paddy field was lowest and it increased with the distance above the water surface, while an inverse relation was observed in the nighttime. On the other hand, the pH of the ponded water changed significantly throughout a day and was expected to affect atmospheric CO2 in the vicinity of the water surface, because the solubility of CO2 in water depends on the pH. In this study, we investigated the relationship between the changes in the pH of the ponded water and the response of the CO2 concentration in the air above the water. The pH of the ponded water of the paddy field increased in the daytime and decreased in the nighttime, so that the water was alkaline in the daytime and weakly acidic in the nighttime. We found that the daily changes in the atmospheric CO2 concentration gradient almost corresponded to the daily changes in pH. The increase of the pH of the ponded water in the daytime was due to the absorption of dissolved CO2 by photosynthetic bacteria and micro-algae within the ponded water. Furthermore, we compared the pH with RpH, defined as the pH at which the CO2 concentration of the water is in equilibrium with that of the air, to determine whether CO2 was absorbed by or emitted from the ponded water. In the daytime, the pH value of the ponded water was higher than that of the RpH, and the water could therefore absorb CO2 , whereas during the nighttime, since the pH value of the ponded water was lower than that of the RpH, the water was expected to emit CO2. These results show that the ponded water absorbed CO2 from the air above the water surface in the daytime and emitted CO2 in the nighttime.  相似文献   
59.
In the present study, the comparative effects of osmotic and ionic stresses on rice growth and yield were investigated. The treatments consisted of 3-level combinations of osmotic stress and times: medium (-0.25 MOPa),and high stress (-0.52 MPa)'app0ied at the vegetative stage (7-21 d after transplanting, DAT)and reproductive stage (35-63 DAT, starting when the rice plant reached panicle initiation). NaCl and polyethylene glycol (PEG) were used as sources of osmotic stress. Both sources applied at the vegetative and reproductive stages delayed flowering, maturity and reduced the total biomass compared with the controD.Na+ concentration in the plant increased with NaCl addition but not with PEG, indicating that the plants were also subjected to ionic stress besides osmotic stress. There was no significant difference in biomass accumulation and yield between the PEG- and NaCl-treatments,imdicating that the salinity effect was mainly due to osmotic stress.  相似文献   
60.
The objective of this study was to determine the effect of foliar salicylic acid (SA) applications on growth, chlorophyll, and mineral content of cucumber grown under salt stress. The study was conducted in pot experiments under greenhouse conditions. Cucumber seedlings were treated with foliar SA applications at different concentrations (0.0, 0.25, 0.50, and 1.00 mM). Salinity treatments were established by adding 0, 60, and 120 mM of sodium chloride (NaCl) to a base complete nutrient solution. The SA was applied with spraying two times as before and after transplanting. Salt stress negatively affected the growth, chlorophyll content and mineral uptake of cucumber plants. However, foliar applications of SA resulted in greater shoot fresh weight, shoot dry weight, root fresh weight, and root dry weight as well as higher plants under salt stress. Shoot diameter and leaf number per plant increased with SA treatments under salt stress. The greatest chlorophyll content was obtained with 1.00 mM SA treatment in both saline and non-saline conditions. Leaf water relative content (LWRC) reduced in response to salt stress while SA raised LWRC of salt stressed cucumber plants. Salinity treatments induced significant increases in electrolyte leakage. Plants treated with foliar SA had lower values of electrolyte leakage than non-treated ones. In regard to nutrient content, it can be interfered that foliar SA applications increased almost all nutrient content in leaves and roots of cucumber plants under salt stress. Generally, the greatest values were obtained from 1.00 mM SA application. Based on these findings, the SA treatments may help alleviate the negative effect of salinity on the growth of cucumber.  相似文献   
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