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401.
This study was undertaken to investigate the occurrence and public health significance of Cryptosporidium species/genotypes and subtypes in a newborn lambs. A total of 175 diarrheic fecal samples from lambs (younger than 21 days) were collected in seven sheep flocks located in western Romania, and were microscopically examined for the presence of Cryptosporidium oocysts after staining with modified Ziehl–Neelsen technique. Twenty-four (13.7%) fecal samples were tested Cryptosporidium positive by microscopy and were subjected for molecular characterization. All positive samples were successfully amplified through a nested polymerase chain reaction (PCR) of the small subunit (SSU) rRNA gene (18S). Cryptosporidium species were determined by restriction fragment length polymorphism (RFLP) analysis of the secondary PCR products using the conventional SspI and VspI restriction enzymes. The identified species were: Cryptosporidium parvum (20/24), C. ubiquitum (2/24) and C. xiaoi (2/24), respectively. PCR-RFLP results for C. ubiquitum and C. xiaoi isolates were confirmed by DNA sequencing. Subsequently, subtyping of seven randomly selected C. parvum isolates, based on sequence analysis of the GP60 gene, revealed the presence of five different subtypes (IIaA17G1R1, IIaA16G1R1, IIdA20G1, IIdA24G1 and IIdA22G2R1) belonging in two zoonotic subtype families (IIa and IId). These findings may suggest the potential role of the newborn lambs as a source for human cryptosporidiosis. This is the first published report about the presence of C. ubiquitum and C. xiaoi in lambs from Romania.  相似文献   
402.
1. The objective of the study was to investigate the effects of breeder age and egg weight on hatching performance and morphological changes in segments of the small intestine of broiler chicks during a 21 h hatch window.

2. Eggs from Ross broiler breeder flocks aged 29 (young) and 48 weeks (old) were classified as light (LE) or heavy (HE) and incubated at the same conditions. At 475 h of incubation, eggs were checked every 3 h to determine time of external pipping and hatching. The first 42 chicks to emerge from each group were weighed and chick length was measured and 14 chicks from each group were sampled to collect residual yolk and intestine segments. The rest of chicks were placed back in the incubator and chick weight and length were measured individually at 9, 15 and 21 h after chicks hatched. At the end of 21 h, 14 chicks from each group were sampled again and the same procedure was followed.

3. The HE chicks pipped and hatched later than LE, regardless of breeder age. From hatch to the end of the hatch window, chick weight, but not yolk-free chick weight, gradually reduced. Relative residual yolk weight of chicks from both egg weights was similar at hatch, however, yolk sac utilisation was higher for LE chicks during the 21 h post-hatch period. At hatch, jejunum and ileum villus development was very similar for HE and LE chicks but greater development was observed for villus area with an increase in the jejunum villus length, width and goblet cell numbers in HE chicks.

4. The longest jejunum villus and the widest duodenum and jejunum villus were obtained for HE chicks from old breeders indicating that HE chicks from old breeders would have a greater surface area for nutrient absorption.  相似文献   

403.
Control of regular cropping in apple is considered critical for fruit growers to ensure their economical sustainability. Irregular flowering can be mitigated by plant growth regulators thanks to their promotion or inhibition effects. In this study, responses of GA4+7 and ethephon on alternate bearing in ‘Golden Delicious’/M9 were examined. GA4+7 and ethephon were applied on the same trees during three consecutive years (2010–12). Flowering, yield, shoot growth, and also some fruit quality parameters were assessed. GA4+7 appeared to be more effectual to regulate alternate bearing. The alternate bearing index calculated with yield in successive years was high in control (0.91), moderate in ethephon (0.71), and low in GA4+7 treated trees (0.41). Modified alternate bearing index, based on cluster number, indicated moderate intensity in GA4+7 (0.53) and high intensity in the others. Although GA4+7 reduced crop density at about 50%, there was little variation in yield per tree and crop efficiency due to increasing of fruit size. GA4+7 did not increase shot length after establishment of equilibrium between vegetative and generative growth in 2012. Ethephon slightly reduced vegetative growth and relatively increased fruit size due to the decrease of fruit set.  相似文献   
404.
In this selection survey that was performed to select the types with superior properties among the population of seedling walnut trees in Çank?r? location, fruit samples were collected individually from 67 trees. Than these types were evaluated for fruit and tree properties and eight walnut types with fruit weight between 11.90 and 15.83 g, interior weight between 6.66 and 8.82 g, the interior ratio between 53.06 and 60.41?%, shell thickness between 1.21 and 1.50 mm were selected as promising. For these types the shell color was determined as dark in two types and tawny in six types. The inner color was found to be light yellow in four types and dark yellow in four types. The selected types were in a good condition for full and sound interior ratio. Seven types gave 100?% full and sound inner. Whereas one type gave 20?% empty fruit. Four types showed homogamous blooming, one types showed protandrous blooming and three types displayed protogynous blooming. The total oil content of selected types varied from 43.16 to 58.68?%. The range of fatty acid contents in the fruits of these types were also determined between 50.83 and 60.77?% for linoleic acid, between 16.14 and 26.44?% for oleic acid, between 5.42 and 7.29?% for palmitic acid, between 11.08 and 14.25?% for linolenic acid and between 1.70 and 2.55?% for stearic acid.  相似文献   
405.
A series of experiments were conducted in which label rate (0.3 g per kg of wheat) with diatomaceous earth (DE) formulation Protect-It. Exposure studies were carried out at two levels of relative humiditiy (40% and 55%), two levels of insect density (10 or 20 adults per vial), and three levels of exposure periods. Test insects were placed in vials containing 40 g of soft white winter wheat mixed with either 0 or 0.3 g Protect-It per kg of wheat. After relating exposure periods for both insect density and relative humidity levels, highest mortality was only 16%. Mortality, regardless of the dose rate applied (0 and 0.3 g) were not significantly increased as the exposure period increased. Regardless of relative humidity (r.h.) (40% and 55%r.h.), mortality in control were not significantly increased as the exposure period increased for the same insect density. However, significant differences among the three exposure periods in 10 adults’ density in 0.3 g DE application. Mortality was significantly increased in 10 adults’ density. In this case mortality of R. dominica adults increased with the increasing of the exposure intervals. As for 20 adults’ density, mortality in 0.3 g DE application was not significantly changed along with the exposure intervals. After insects were exposed for 1, 2, or 3 week, dead and live insects were removed, and the wheat in the vial were returned to relating humidity box and kept for 8 week until F1 adults emerged. Then, the number of F1 adult was counted. The mean numbers of F1 adults on untreated wheat at all density and r.h. combinations, regardless of exposure periods were significantly higher than that of 0.3 g DE- treated wheat (Fig. 3). At each density and treatment, the mean number of F1 adults at 55% r.h. were higher that that of 40%r.h. The comparison between adult densities at each r.h. and treatment showed that adult densities influenced the F1 production of R. dominica and F1 adults were always higher at 20 adults’ density. The mean number of F1 adults at each density, regardless of treatment progressively increased as the exposure period increased. Fewer progeny were produced at 10 adults’ density compared to 20 adults’ density for same exposure periods. The highest reproduction occurred in 3 week of exposure period for both insect densities. Regardless of adult densities, the mean number of F1 adults was significantly increased as the exposure period increased (Fig. 5) for both control and 0.3 g DE treatment. Reduction of F1 adults at 0.3 g DE application compared to control were found to be 76.88, 74.78 and 67.63% for 1, 2 and 3 week of exposure period, respectively.  相似文献   
406.
The ethanol and methanol extracts of Arbutus unedo leaves were screened for antioxidant activity. The antioxidant activity was determined by an improved assay based on the decolorization of the radical monocation of [2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS). The ethanol and methanol extract of A. unedo leaves displayed potent antioxidant activity.  相似文献   
407.
408.
Summary Soxhlet and supercritical fluid extracts of freshly cut oriental beech (Fagus orientalis) have been obtained using acetone. While the yield of the Soxhlet extract was 2.54% the yield of the supercritical acetone extract obtained at 240°C and 6.0–6.5 MPa was 9.55% (dry wood basis). The fatty acids present in the extracts were separated by chemical and Chromatographic methods and analysed by combined gas chromatography and mass spectrometry. Linoleic acid was the major fatty acid in both extracts.  相似文献   
409.
This study was carried out to determine the development, survival and reproduction responses of Adalia fasciatopunctata revelierei (Mulsant) (Coleoptera: Coccinellidae) feeding on Hyalopterus pruni (Geoffroy) (Homoptera: Aphididae), using 20, 40, 80, 160 and 250 prey densities. All experiments were conducted at 25±1°C, 60±5% relative humidity, 16:8 light:dark under laboratory conditions. The average daily prey consumption of A. fasciatopunctata revelierei immatures and adults increased with increasing prey densities. Predation was not different for the larval stages at 80, 160 and 250 prey densities. The longevities of adult females were 35.67, 35.33, 49.00, 58.33 and 57.16 days when 20, 40, 80, 160 and 250 H. pruni were provided, respectively. The mean daily and total fecundity of A. fasciatopunctata revelierei increased with increasing prey densities. Females of A. fasciatopunctata revelierei feeding on H. pruni laid 89 eggs at 20 prey density and 301.67 eggs at 160 prey density. The search rate of females was higher than that of all larval instars; and the search rate of the fourth-instar larvae was higher than that of younger instars. Handling time decreased with development from larval stages to adult.  相似文献   
410.
Journal of Plant Diseases and Protection - In a walnut orchard in Turkey’s Mersin province in the summer of 2021, phytoplasma related symptoms such as abnormal formations in flowers...  相似文献   
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