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21.
A fusion DNA vaccine co-expressed Eimeria tenella TA4 and chicken IL-2 (chIL-2) was constructed and its efficacy against E. tenella challenge was observed. TA4 gene of E. tenella and chIL-2 gene were cloned into expression vector pcDNA3.1 and pcDNA4.0c in different forms, producing vaccines pcDNA3.1-TA4-IL-2, pcDNA3.1-TA4 and pcDNA4.0c-IL-2. The expression of aim genes in vivo was detected by RT-PCR and western blot. Animal experiment was carried out to evaluate the immune efficacy of the vaccines. Results indicated these DNA vaccines were successfully constructed and the antigen genes could be expressed effectively in vivo. The animal experimental results showed that DNA vaccines could obviously alleviate cecal lesions, body weight loss and increase oocyst decrease ratio. The ACI of pcDNA3.0-TA4-IL-2 group was 192, higher than that of pcDNA3.1-TA4 group. The results suggested that TA4 was an effective candidate antigen for vaccine and co-expression of cytokine with antigen was an alternative method to enhance DNA vaccine immunity. 相似文献
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Fernando Machado-Stredel Benedictus Freeman Daniel Jiménez-Garcia Marlon E.Cobos Claudia Nu?ez-Penichet Laura Jiménez Ed Komp Utku Perktas Ali Khalighifar Kate Ingenloff Walter Tapondjou Thilina de Silva Sumudu Fernando Luis Osorio-Olvera A.Townsend Peterson 《中国鸟类》2022,(1):1-10
Studies of biodiversity dynamics have been cast on either long(systematics)or short(ecology)time scales,leaving a gap in coverage for moderate time scales of de... 相似文献
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Mehdi Zarifi Sébastien Buczinski Ali Rezakhani Mohammad Reza Mokhber Dezfouli Ali Khonsha 《Journal of Veterinary Cardiology》2012,14(3):415-421
ObjectivesTo study the effect of pregnancy and lactation on echocardiographic parameters in Holstein dairy cows.AnimalsNine multiparous high milk producing (HMP) dairy cows (producing more than 40 kg of milk per day in peak production) and 9 low milk producing (LMP) cows (producing less than 30 kg or milk per day in peak production).MethodsEchocardiography was performed twice; one month before calving and two months after calving.ResultsThe heart rate of HMP cows in the early lactation period was significantly higher than in the dry period. In LMP cows, there was a significant increase in left ventricular dimension in the early lactation period as compared to the dry period, and the interventricular septum in systole (IVSs) in the dry period was significantly thicker than early lactation period. In HMP cows, there was an increase in the right ventricular diameter in systole in the early lactation period as compared to the dry period. Left ventricular and aortic dimensions in the dry period of HMP were significantly higher than those of LMP cows. When the data were corrected for body weight, comparison of values of the dry period of HMP and LMP cows showed that left ventricular volume in systole in HMP was significantly higher and that IVSs, left ventricular fractional shortening and ejection fraction were significantly lower than in LMP cows.ConclusionsThis study demonstrated that lactation influences the intracardiac dimensions. The amount of milk production can influence echocardiographic parameters in dairy cows. 相似文献
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Journal of Plant Diseases and Protection - In the original publication, the article title was incorrectly published as ‘Impact of leave infestation by herbivorous insects on the elemental... 相似文献
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The effects of maternal salinity and light incubation on the salinity tolerance of the facultative halophyte Anabasis setifera during their germination stages were assessed. Seeds were collected from non-saline habitats in Egypt and saline habitats in the United Arab Emirates(UAE). The seeds of the two populations were germinated in 0, 100, 200, 400, 600 and 800 m M Na Cl, and incubated at 25°C/15°C in both 12-h light and 12-h darkness regimes and continuous darkness. Significantly more seeds germinated in the Egyptian population than in the UAE population. Salinity tolerance was significantly greater with the Egyptian population than with the UAE population, especially under the conditions of higher salinities. The difference in salinity tolerance between the seeds of two populations was attributed to their seed mass. In addition, germination was significantly faster for the Egyptian population than for the UAE population. Most of the saline treated seeds were able to recover their germination when transferred to distilled water, but this depended on their maternal salinity and light incubation. Recovery from higher salinities was significantly better for the seeds under darkness than for those under light in the UAE population, but the reverse was true for the seeds in the Egyptian population. The higher salinity tolerance for the A. setifera seeds from the non-saline Egyptian population and the lower salinity tolerance for the seeds from the saline UAE population cannot explain their natural distribution. Further studies about other possible roles, such as levels of different promoting and inhibiting phytohormones, are needed to understand the importance of salinity as an environmentally induced maternal effect. 相似文献
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Tan spot of wheat, caused by the fungus Pyrenophora tritici-repentis, is a destructive disease worldwide that can lead to serious losses in quality and quantity of wheat grain production. Resistance to multiple races of P. tritici-repentis was identified in a wide range of genetically diverse genotypes, including three different species Triticum aestivum (AABBDD), T. spelta (AABBDD), and T. turgidum (AABB). The major objectives of this study were to determine the genetic control of resistance to P. tritici-repentis races 1 and 5 in 12 newly identified sources of resistance. The parents, F(1), F(2), and F(2:3) or F(2:5) families of each cross were analyzed for the allelism tests and/or inheritance studies. Plants were inoculated at the two-leaf stage under controlled environmental conditions and disease reaction was assessed based on lesion-type rating scale. A single recessive gene controlled resistance to necrosis caused by P. tritici-repentis race 1 in both tetraploid and hexaploid resistant genotypes. The lack of segregation in the inter- and intra-specific crosses between the resistant tetraploid and hexaploid genotypes indicated that they possess the same genes for resistance to tan necrosis and chlorosis induced by P. tritici-repentis race 1. A single dominant gene for chlorosis in hexaploid wheat and a single recessive gene for necrosis in tetraploid wheat, controlled resistance to P. tritici-repentis race 5. 相似文献
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Jalal Soltani Ali A. Aliabadi 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(1):65-70
Bacterial blight disease of Persian walnut (Juglans regia, L.), caused by Xanthomonas arboricola pv. juglandis (Xaj), leads to significant nut losses in northern, central and western areas of Iran. To identify the natural sources of resistance
to disease in the endemic walnut genotypes of Iran, sixteen walnut genotypes, collected from different areas of Hamedan province,
were inoculated with Xaj in a randomized complete block design with five replicates for each genotype. Two-year old genotypes were gently sprayed
with a suspension of bacteria adjusted to approximately 2 × 109 cfu ml−1 of distilled water in May. Infected leaves were rated for disease 28 and 42 days after inoculation, using a 0 to 5 severity
scale, based on the number, size and distribution of lesions on the leaves. Data analyses showed that there were variations
among genotypes in response to pathogen. Upon inoculation by bacterial suspension genotype 94 showed the highest resistance
to both disease incidence and its progress after 4–6 weeks of infection. Genotype 65 showed high susceptibility to disease
and genotype 69 showed high susceptibilities both to disease incidence and its progress after 4–6 weeks of infection. 相似文献