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21.
22.
Efficacy of an orally administered modified-live porcine-origin rotavirus vaccine against postweaning diarrhea in pigs 总被引:3,自引:0,他引:3
K H Hoblet L J Saif E M Kohler K W Theil S Bech-Nielsen G A Stitzlein 《American journal of veterinary research》1986,47(8):1697-1703
A commercially available, porcine-origin rotavirus vaccine was evaluated for efficacy against postweaning diarrhea due to rotavirus infection in pigs. Weight gains were compared at 5 intervals after weaning. Visual scoring was used to evaluate fecal consistency. Rectal swab specimens were cultured for hemolytic E coli and evaluated for rotaviral antigen by use of enzyme-linked immunosorbent assay. Milk from dams and sera from pigs and dams were evaluated for rotavirus-neutralizing antibodies by use of a plaque-reduction test. Significant differences between vaccinates and controls were not found in the determinants evaluated. Selected rotavirus-positive fecal and rectal swab specimens were examined for double-stranded (ds) RNA by use of direct electropherotyping, and the results were compared with the dsRNA pattern of rotavirus propagated from the vaccine. Only electropherotypes typical of field strain virus were found in the fecal and rectal swab specimens evaluated. Sera from guinea pigs and from a gnotobiotic pig immunized against the field strain rotavirus neutralized Ohio State University strain rotavirus (homologous to the vaccine rotavirus strain), but did not neutralize the Gottfried strain of rotavirus. This indicated that, although the dsRNA electropherotypes of the field and vaccine strains of the virus were different, the serotypes were similar, if not identical. 相似文献
23.
24.
An avidin-biotin-enhanced enzyme-linked immunosorbent assay (AB-ELISA) and an avidin-biotin-enhanced dot-immunobinding (AB-DIB) assay for detecting antibody to Bordetella avium in turkey sera were developed and compared with the microagglutination (MA) test. Whole-cell antigen, biotin-labeled goat anti-turkey IgG conjugate, and horseradish-peroxidase-labeled streptavidin were used in the AB-ELISA and AB-DIB assay. The AB-ELISA and AB-DIB assay were sensitive, specific, and reproducible. These assays were superior to the MA test for measuring acquired and maternal antibodies against B. avium. All MA-positive sera were positive by two assays, but some sera negative by MA test had titers in the AB-ELISA and AB-DIB assay. AB-ELISA and AB-DIB titers showed a positive correlation (r = 0.866), and AB-ELISA was more sensitive than the AB-DIB assay. 相似文献
25.
Khalid A. ABDOUN Emad M. SAMARA Aly B. OKAB Ahmed A. AL‐HAIDARY 《Animal Science Journal》2012,83(7):556-561
It was the aim of this study to investigate the regional variations in surface temperature and sweating rate and to visualize body thermal windows responsible for the dissipation of excess body heat in dromedary camels. This study was conducted on five dromedary camels with mean body weight of 450 ± 20.5 kg and 2 years of age. Sweating rate, skin and body surface temperature showed significant (P < 0.001) circadian variation together with the variation in ambient temperature. However, daily mean values of sweating rate, skin and body surface temperature measured on seven regions of the camel body did not significantly differ. The variation in body surface temperature compared to the variation in skin temperature was higher in the hump compared to the axillary and flank regions, indicating the significance of camel's fur in protecting the skin from daily variation in ambient temperature. Infrared thermography revealed that flank and axillary regions had lower thermal gradients at higher ambient temperature (Ta) and higher thermal gradients at lower Ta, which might indicate the working of flank and axillary regions as thermal windows dissipating heat during the night. Sweating rate showed moderate correlation to skin and body surface temperatures, which might indicate their working as potential thermal drivers of sweating in camels. 相似文献
26.
Seed presoaking improves wheat germination under marginal moisture conditions. The duration of seed presoaking was studied at The University of Arid Agriculture, Rawalpindi, using 10 wheat varieties. Seed presoaking beyond 12 h does not improve germination further, and beyond 21 h, germination rate is drastically reduced. 相似文献
27.
Mohammed F. Aldawsari Mohammed Muqtader Ahmed Farhat Fatima Md. Khalid Anwer Prakash Katakam Abdullah Khan 《Marine drugs》2021,19(8)
The objective of this work was to develop sustained-release Ca-alginate beads of apigenin using sodium alginate, a natural polysaccharide. Six batches were prepared by applying the ionotropic gelation technique, wherein calcium chloride was used as a crosslinking agent. The beads were evaluated for particle size, drug loading, percentage yield, and in vitro drug release. Particle size was found to decrease, and drug entrapment efficiency was enhanced with an increase in the polymer concentration. The dissolution study showed sustained drug release from the apigenin-loaded alginate beads with an increase in the polymer proportion. Based on the dissolution profiles, BD6 formulation was optimized and characterized for FTIR, DSC, XRD, and SEM, results of which indicated successful development of apigenin-loaded Ca alginate beads. MTT assay demonstrated a potential anticancer effect against the breast cancer MCF-7 cell lines. The antimicrobial activity exhibited effective inhibition in the bacterial and fungal growth rate. The DPPH measurement revealed that the formulation had substantial antioxidant activity, with EC50 value slightly lowered compared to pure apigenin. A stability study demonstrated that the BD6 was stable with similar (f2) drug release profiles in harsh condition. In conclusion, alginate-based beads could be used for sustaining the drug release of poorly water-soluble apigenin while also improving in vitro antitumor, antimicrobial, and antioxidant activity. 相似文献
28.
Azhar Abbas Muhammad Yaseen Muhammad Khalid Muhammad Naveed Muhammad Zahir Aziz Yasir Hamid 《Journal of plant nutrition》2017,40(16):2303-2311
A field experiment was conducted to evaluate effect of biochar-amended urea on nitrogen economy of soil for improving the growth and yield of wheat under field condition. Experiment plan was comprised of twelve treatments with four replications including treatments without application of urea and biochar (control) and urea only. Biochar was applied at 1–10% of the weight of urea fertilizer applied each treatment. Results showed that application of biochar at 10% with recommended dose of urea significantly improved plant height, spike length, number of tillers, number of spikelet per spike, 1000 grain weight, grain yields, biomass yield, harvesting index, nitrogen (N) concentration and uptake in grain and straw, and agronomic efficiency of nitrogen by 6.0%, 11.1%, 32.0%, 55.3%, 5.4%, 38.0%, 19.0%, 9.0%, 19.0%, 26.0%, 65.0%, 50.0%, and 63.0%, respectively, as compared to treatment comprised of recommended rate of nitrogen without biochar. 相似文献
29.
Ragab Abdelmohsen E-Mergawi ;Khalid Naser Al-Redhaiman ;Hussein F. Abouziena 《农业科学与技术》2014,(7):597-604
The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP), total phenolics, ascorbic acid, total carotene and lycopene contents in edible portions of lettuce, onion and tomato due to different nitrogen levels and sources. The experiment included three N levels (20, 40 and 60 kg/ha for lettuce trial and 60, 120 and 180 kg/ha for either onion or tomato) and four nitrogen sources (calcium nitrate, ammonium sulphate, ammonium nitrate and urea). The antioxidant capacity and phenolic contents in lettuce was enhanced under low nitrogen level, while the antioxidant capacities, phenolics, carotenoids and lycopene in tomato fruits were not significantly affected by the nitrogen dose applied. Application of calcium nitrate caused 50% increase in DPPH and 20% in FRAP of lettuce compared to other nitrogen forms. Tomato treated with calcium nitrate or ammonium sulphate had higher phenolic and ascorbic acid contents than treated plants with ammonium nitrate or urea. Antioxidant tested parameters of onion were not significantly affected by the nitrogen treatments. Nitrogen concentration in tomato fruits significantly correlated with FRAP antioxidant capacity, phenolics, ascorbic acid, carotene and lycopene contents. 相似文献
30.
Comparative studies on three isolates of Breda virus of calves 总被引:8,自引:0,他引:8
G N Woode L J Saif M Quesada N J Winand J F Pohlenz N K Gourley 《American journal of veterinary research》1985,46(5):1003-1010
Three isolates of Breda virus of calves were compared morphologically and antigenically. The isolates demonstrated similar morphology and shared common antigens, as determined by enzyme-linked immunosorbent assay and immunoelectron microscopy. On the basis of results of the hemagglutination-inhibition test, enzyme-linked immunosorbent assay, and immunoelectron microscopy, the 3 isolates were further subdivided into 2 serotypes: serotype 1 (Breda virus 1) represented by the Iowa isolate 1; and serotype 2 (Breda virus 2), by the Ohio isolate and the Iowa isolate 2. The 3 isolates caused diarrhea in gnotobiotic calves. 相似文献